After the previous patch, we end up with these two types with quite
similar, and potentially confusing names:
typedef gdb::unique_ptr<agent_expr> agent_expr_up;
/* Pointer to an agent_expr structure. */
typedef struct agent_expr *agent_expr_p;
The latter is only necessary to put agent_expr pointers in VECs. So
just eliminate it and use std::vector instead.
gdb/ChangeLog:
2016-11-08 Pedro Alves <palves@redhat.com>
* ax.h (agent_expr_p): Delete.
(DEF_VEC_P (agent_expr_p)): Delete.
* breakpoint.c (build_target_condition_list)
(build_target_command_list): Adjust to use of std::vector.
(bp_location_dtor): Remove now unnecessary VEC_free calls.
* breakpoint.h: Include <vector>.
(struct bp_target_info) <conditions, tcommands>: Now
std::vector's.
* remote.c (remote_add_target_side_condition): bp_tgt->conditions
is now a std::vector; adjust.
(remote_add_target_side_commands, remote_insert_breakpoint):
bp_tgt->tcommands is now a std::vector; adjust.
This patch makes the gen_* functions return a unique_ptr instead of
raw pointer:
typedef gdb::unique_ptr<agent_expr> agent_expr_up;
and then adjusts the codebase throughout to stop using
make_cleanup_free_agent_expr.
The cond_bytecode and cmd_bytecode fields of struct bp_location are
owning pointers, so they're changed to be unique_ptr's instead of raw
pointers.
gdb/ChangeLog:
2016-11-08 Pedro Alves <palves@redhat.com>
* ax-gdb.c (is_nontrivial_conversion): Use agent_expr_up.
(gen_trace_for_var, gen_trace_for_expr, gen_eval_for_expr)
(gen_trace_for_return_address, gen_printf): Use and return an
agent_expr_up. Don't use make_cleanup_free_agent_expr.
(agent_eval_command_one, maint_agent_printf_command): Use
agent_expr_up. Don't use make_cleanup_free_agent_expr.
* ax-gdb.h (gen_trace_for_expr, gen_trace_for_var)
(gen_trace_for_return_address, gen_eval_for_expr, gen_printf): Use
agent_expr_up.
* ax-general.c (new_agent_expr): Rename to ...
(agent_expr::agent_expr): ... this, and now a constructor.
(free_agent_expr): Rename to ...
(agent_expr::~agent_exp): ... this, and now a destructor.
(do_free_agent_expr_cleanup, make_cleanup_free_agent_expr):
Delete.
* ax.h (struct agent_expr): Add ctor/dtor.
(agent_expr_up): New typedef.
(new_agent_expr, free_agent_expr, make_cleanup_free_agent_expr):
Delete declarations.
* breakpoint.c (parse_cond_to_aexpr): Use and return an
agent_expr_up. Don't use make_cleanup_free_agent_expr.
(build_target_condition_list): Adjust to use agent_expr_up.
(parse_cmd_to_aexpr): Use and return an agent_expr_up. Don't use
make_cleanup_free_agent_expr.
(build_target_command_list): Adjust to use agent_expr_up.
(force_breakpoint_reinsertion): Adjust to use agent_expr_up.
(bp_location_dtor): Remove unnecessary free_agent_expr and xfree
calls.
* breakpoint.h (struct bp_target_info) <cond_bytecode,
cmd_bytecode>: Now agent_expr_up's.
* remote.c (remote_download_tracepoint): Adjust to use
agent_expr_up and remove use of make_cleanup_free_agent_expr.
* tracepoint.c (validate_actionline, collect_symbol): Adjust to
use agent_expr_up and remove uses of make_cleanup_free_agent_expr.
(collection_list::~collection_list): Call delete instead of
free_agent_expr.
(encode_actions_1): Adjust to use agent_expr_up and remove uses of
make_cleanup_free_agent_expr.
(add_aexpr): Change parameter type to agent_expr_up; Return a raw
agent_expr pointer.
This replaces most of the remaining ui_file_xstrdup calls with
ui_file_as_string calls. Whenever a call was replaced, that led to a
cascade of other necessary adjustments throughout, to make the code
use std::string instead of raw pointers. And then whenever I added a
std::string as member of a struct, I needed to adjust
allocation/destruction of said struct to use new/delete instead of
xmalloc/xfree.
The stopping point was once gdb built again. These doesn't seem to be
a way to reasonably split this out further.
Maybe-not-obvious changes:
- demangle_for_lookup returns a cleanup today. To get rid of that,
and avoid unnecessary string dupping/copying, this introduces a
demangle_result_storage type that the caller instantiates and
passes to demangle_for_lookup.
- Many methods returned a "char *" to indicate that the caller owns
the memory and must free it. Those are switched to return a
std::string instead. Methods that return a "view" into some
internal string return a "const char *" instead. I.e., we only
copy/allocate when necessary.
gdb/ChangeLog:
2016-11-08 Pedro Alves <palves@redhat.com>
* ada-lang.c (ada_name_for_lookup, type_as_string): Use and return
std::string.
(type_as_string_and_cleanup): Delete.
(ada_lookup_struct_elt_type): Use type_as_string.
* ada-lang.h (ada_name_for_lookup): Now returns std::string.
* ada-varobj.c (ada_varobj_scalar_image): Return a std::string.
(ada_varobj_describe_child): Make 'child_name' and
'child_path_expr' parameters std::string pointers.
(ada_varobj_describe_struct_child, ada_varobj_describe_ptr_child):
Likewise, and use string_printf.
(ada_varobj_describe_simple_array_child)
(ada_varobj_describe_child): Likewise.
(ada_varobj_get_name_of_child, ada_varobj_get_path_expr_of_child)
(ada_varobj_get_value_image)
(ada_varobj_get_value_of_array_variable)
(ada_varobj_get_value_of_variable, ada_name_of_variable)
(ada_name_of_child, ada_path_expr_of_child)
(ada_value_of_variable): Now returns std::string. Use
string_printf.
(ada_value_of_child): Adjust.
* break-catch-throw.c (check_status_exception_catchpoint): Adjust
to use std::string.
* breakpoint.c (watch_command_1): Adjust to use std::string.
* c-lang.c (c_get_string): Adjust to use std::string.
* c-typeprint.c (print_name_maybe_canonical): Use std::string.
* c-varobj.c (varobj_is_anonymous_child): Use ==/!= std::string
operators.
(c_name_of_variable): Now returns a std::string.
(c_describe_child): The 'cname' and 'cfull_expression' output
parameters are now std::string pointers. Adjust.
(c_name_of_child, c_path_expr_of_child, c_value_of_variable)
(cplus_number_of_children): Adjust to use std::string and
string_printf.
(cplus_name_of_variable): Now returns a std::string.
(cplus_describe_child): The 'cname' and 'cfull_expression' output
parameters are now std::string pointers. Adjust.
(cplus_name_of_child, cplus_path_expr_of_child)
(cplus_value_of_variable): Now returns a std::string.
* cp-abi.c (cplus_typename_from_type_info): Return std::string.
* cp-abi.h (cplus_typename_from_type_info): Return std::string.
(struct cp_abi_ops) <get_typename_from_type_info>: Return
std::string.
* cp-support.c (inspect_type): Use std::string.
(cp_canonicalize_string_full, cp_canonicalize_string_no_typedefs)
(cp_canonicalize_string): Return std::string and adjust.
* cp-support.h (cp_canonicalize_string)
(cp_canonicalize_string_no_typedefs, cp_canonicalize_string_full):
Return std::string.
* dbxread.c (read_dbx_symtab): Use std::string.
* dwarf2read.c (dwarf2_canonicalize_name): Adjust to use std::string.
* gdbcmd.h (lookup_struct_elt_type): Adjust to use std::string.
* gnu-v3-abi.c (gnuv3_get_typeid): Use std::string.
(gnuv3_get_typename_from_type_info): Return a std::string and
adjust.
(gnuv3_get_type_from_type_info): Adjust to use std::string.
* guile/guile.c (gdbscm_execute_gdb_command): Adjust to use
std::string.
* infcmd.c (print_return_value_1): Adjust to use std::string.
* linespec.c (find_linespec_symbols): Adjust to
demangle_for_lookup API change. Use std::string.
* mi/mi-cmd-var.c (print_varobj, mi_cmd_var_set_format)
(mi_cmd_var_info_type, mi_cmd_var_info_path_expression)
(mi_cmd_var_info_expression, mi_cmd_var_evaluate_expression)
(mi_cmd_var_assign, varobj_update_one): Adjust to use std::string.
* minsyms.c (lookup_minimal_symbol): Use std::string.
* python/py-varobj.c (py_varobj_iter_next): Use new instead of
XNEW. vitem->name is a std::string now, adjust.
* rust-exp.y (convert_ast_to_type, convert_name): Adjust to use
std::string.
* stabsread.c (define_symbol): Adjust to use std::string.
* symtab.c (demangle_for_lookup): Now returns 'const char *'. Add
a demangle_result_storage parameter. Use it for storage.
(lookup_symbol_in_language)
(lookup_symbol_in_objfile_from_linkage_name): Adjust to new
demangle_for_lookup API.
* symtab.h (struct demangle_result_storage): New type.
(demangle_for_lookup): Now returns 'const char *'. Add a
demangle_result_storage parameter.
* typeprint.c (type_to_string): Return std::string and use
ui_file_as_string.
* value.h (type_to_string): Change return type to std::string.
* varobj-iter.h (struct varobj_item) <name>: Now a std::string.
(varobj_iter_delete): Use delete instead of xfree.
* varobj.c (create_child): Return std::string instead of char * in
output parameter.
(name_of_variable, name_of_child, my_value_of_variable): Return
std::string instead of char *.
(varobj_create, varobj_get_handle): Constify 'objname' parameter.
Adjust to std::string fields.
(varobj_get_objname): Return a const char * instead of a char *.
(varobj_get_expression): Return a std::string.
(varobj_list_children): Adjust to use std::string.
(varobj_get_type): Return a std::string.
(varobj_get_path_expr): Return a const char * instead of a char *.
Adjust to std::string fields.
(varobj_get_formatted_value, varobj_get_value): Return a
std::string.
(varobj_set_value): Change type of 'expression' parameter to
std::string. Use std::string.
(install_new_value): Use std::string.
(delete_variable_1): Adjust to use std::string.
(create_child): Change the 'name' parameter to a std::string
reference. Swap it into the new item's name.
(create_child_with_value): Swap item's name into the new child's
name. Use string_printf.
(new_variable): Use new instead of XNEW.
(free_variable): Don't xfree fields that are now std::string.
(name_of_variable, name_of_child): Now returns std::string.
(value_of_root): Adjust to use std::string.
(my_value_of_variable, varobj_value_get_print_value): Return
and use std::string.
(varobj_value_get_print_value): Adjust to use ui_file_as_string
and std::string.
* varobj.h (struct varobj) <name, path_expr, obj_name,
print_value>: Now std::string's.
<name_of_variable, name_of_child, path_expr_of_child,
value_of_variable>: Return std::string.
(varobj_create, varobj_get_handle): Constify 'objname' parameter.
(varobj_get_objname): Return a const char * instead of a char *.
(varobj_get_expression, varobj_get_type): Return a std::string.
(varobj_get_path_expr): Return a const char * instead of a char *.
(varobj_get_formatted_value, varobj_get_value): Return a
std::string.
(varobj_set_value): Constify 'expression' parameter.
(varobj_value_get_print_value): Return a std::string.
This patch makes parse_expression and friends return a unique_ptr
instead of raw pointer [1]:
typedef gdb::unique_malloc_ptr<expression> expression_up;
and then adjusts the codebase throughout to stop using cleanups to
manage lifetime of expression pointers.
Whenever I found a structure owning an expression pointer, I made it
store a unique_ptr instead of a raw pointer, which then requires using
new/delete of the holding structure, instead of XNEW/xfree.
[1] - I'd like to set the rule that types named with an "_up" suffix
are unique_ptr typedefs.
Note I used gdb::unique_xmalloc_ptr instead of gdb::unique_ptr, simply
because we still use xmalloc instead of new to allocate expression
objects. Once that's changed, all we need to do is change the
expression_up typedef and the smart pointer will then call delete
instead of xfree.
gdb/ChangeLog:
2016-11-08 Pedro Alves <palves@redhat.com>
* ada-lang.c (ada_read_renaming_var_value): Use expression_up.
(struct ada_catchpoint_location) <excep_cond_expr>: Now an
expression_up.
(ada_catchpoint_location_dtor): Reset excep_cond_expr instead of
using xfree.
(create_excep_cond_exprs): Use expression_up and gdb::move.
(allocate_location_exception): Use new instead of XNEW.
(should_stop_exception): Likewise. Adjust to use expression_up.
(create_ada_exception_catchpoint): Use new instead of XNEW.
* ax-gdb.c (agent_eval_command_one): Use expression_up instead of
cleanups.
(maint_agent_printf_command): Use expression_up.
* break-catch-sig.c (create_signal_catchpoint): Use new instead of
XNEW.
* break-catch-syscall.c (create_syscall_event_catchpoint):
Likewise.
* break-catch-throw.c (handle_gnu_v3_exceptions): Use new instead
of XCNEW. Use gdb::unique_ptr instead of cleanups.
* breakpoint.c (set_breakpoint_condition, update_watchpoint)
(parse_cmd_to_aexpr, watchpoint_check)
(bpstat_check_breakpoint_conditions, watchpoint_locations_match):
Adjust to use expression_up.
(init_bp_location): Adjust.
(free_bp_location): Use delete instead of xfree.
(set_raw_breakpoint_without_location, set_raw_breakpoint)
(add_solib_catchpoint, create_fork_vfork_event_catchpoint)
(new_single_step_breakpoint, create_breakpoint_sal): Use new
instead of XNEW.
(find_condition_and_thread): Adjust to use expression_up.
(create_breakpoint): Use new instead of XNEW.
(dtor_watchpoint): Don't xfree expression pointers, they're
unique_ptr's now.
(insert_watchpoint, remove_watchpoint): Adjust.
(watch_command_1): Use expression_up. Use new instead of XCNEW.
(catch_exec_command_1): Use new instead of XNEW.
(bp_location_dtor): Don't xfree expression pointers, they're
unique_ptr's now.
(base_breakpoint_allocate_location)
(strace_marker_create_breakpoints_sal): Use new instead of XNEW.
(delete_breakpoint): Use delete instead of xfree.
* breakpoint.h (struct bp_location) <cond>: Now an
unique_ptr<expression> instead of a raw pointer.
(struct watchpoint) <exp, cond_exp>: Likewise.
* cli/cli-script.c (execute_control_command): Use expression_up
instead of cleanups.
* dtrace-probe.c (dtrace_process_dof_probe): Use expression_up.
* eval.c (parse_and_eval_address, parse_and_eval_long)
(parse_and_eval, parse_to_comma_and_eval, parse_and_eval_type):
Use expression_up instead of cleanups.
* expression.h (expression_up): New typedef.
(parse_expression, parse_expression_with_language, parse_exp_1):
Change return type to expression_up.
* mi/mi-main.c (mi_cmd_data_evaluate_expression)
(print_variable_or_computed): Use expression_up.
* objc-lang.c (print_object_command): Use expression_up instead of
cleanups.
* parse.c (parse_exp_1, parse_exp_in_context)
(parse_exp_in_context_1, parse_expression)
(parse_expression_with_language): Return an expression_up instead
of a raw pointer.
(parse_expression_for_completion): Use expression_up.
* printcmd.c (struct display) <exp>: Now an expression_up instead
of a raw pointer.
(print_command_1, output_command_const, set_command, x_command):
Use expression_up instead of cleanups.
(display_command): Likewise. Use new instead of XNEW.
(free_display): Use delete instead of xfree.
(do_one_display): Adjust to use expression_up.
* remote.c (remote_download_tracepoint): Likewise.
* stack.c (return_command): Likewise.
* tracepoint.c (validate_actionline, encode_actions_1): Use
expression_up instead of cleanups.
* typeprint.c (whatis_exp, maintenance_print_type): Likewise.
* value.c (init_if_undefined_command): Likewise.
* varobj.c (struct varobj_root) <exp>: Now an expression_up
instead of a raw pointer.
(varobj_create): Adjust.
(varobj_set_value): Use an expression_up instead of cleanups.
(new_root_variable): Use new instead of XNEW.
(free_variable): Use delete instead of xfree.
(value_of_root_1): Use std::swap.
This is constification needed for next patch. Adjust
commands_command_1 to use std::string too because the "arg" parameter
is currently overwritten and then passed to make_cleanup. The
constification alone would trigger a compile error in the make_cleanup
call otherwise (passing const char * to void * parameter). Using
std::string gets rid of the cleanup in the first place, resulting in
simpler code.
gdb/ChangeLog:
2016-11-08 Pedro Alves <palves@redhat.com>
* breakpoint.c (struct commands_info) <arg>: Constify.
(commands_command_1): Constify 'arg' parameter. Use std::string
and string_printf.
(commands_from_control_command): Constify 'arg' parameter.
(map_breakpoint_numbers): Constify 'args' parameter.
* breakpoint.h (commands_from_control_command): Constify 'arg'
parameter.
Remove duplicate `0x'-prefix for the hex address printed. `paddress'
already prepends this, so no need to do it manually.
gdb/ChangeLog:
2016-11-08 Cordian A. Daniluk <th3c0r1uk@gmail.com>
PR breakpoints/20739
* breakpoint.c (check_fast_tracepoint_sals): Don't print duplicate
0x prefix.
This patch adds a new gdbarch method breakpoint_kind_from_current_state
for single step breakpoint, and uses it in breakpoint_kind.
gdb:
2016-11-03 Yao Qi <yao.qi@linaro.org>
* arch-utils.c (default_breakpoint_kind_from_current_state):
New function.
* arch-utils.h (default_breakpoint_kind_from_current_state):
Declare.
* arm-tdep.c (arm_breakpoint_kind_from_current_state): New
function.
(arm_gdbarch_init): Call
set_gdbarch_breakpoint_kind_from_current_state.
* breakpoint.c (breakpoint_kind): Call
gdbarch_breakpoint_kind_from_current_state for single step
breakpoint. Update comments.
* gdbarch.sh (breakpoint_kind_from_current_state): New.
* gdbarch.c, gdbarch.h: Regenerate.
This patch renames placed_size to kind.
gdb:
2016-11-03 Yao Qi <yao.qi@linaro.org>
* breakpoint.h (struct bp_target_info) <placed_size>: Remove.
<kind>: New field.
Update all users.
This patch adds two gdbarch methods breakpoint_kind_from_pc and
sw_breakpoint_from_kind, and uses target_info.placed_size as "kind"
of the breakpoint. This patch updates the usages of
target_info.placed_size.
The "kind" of a breakpoint is determined by gdbarch rather than
target, so we have gdbarch method breakpoint_kind_from_pc, and we
should set target_info.placed_size out of each implementation of
target to_insert_breakpoint. In this way, each target doesn't have
to set target_info.placed_size any more.
This patch also sets target_info.placed_address before
target_insert_breakpoint too, so that target to_insert_breakpoint
can use it, see record_full_insert_breakpoint.
Before we call target_insert_breakpoint, we set
target_info.placed_address and target_info.placed_size like this,
CORE_ADDR addr = bl->target_info.reqstd_address;
bl->target_info.placed_size = gdbarch_breakpoint_kind_from_pc (bl->gdbarch, &addr);
bl->target_info.placed_address = addr;
return target_insert_breakpoint (bl->gdbarch, &bl->target_info);
target_insert_breakpoint may fail, but it doesn't matter to the "kind"
and "placed_address" of a breakpoint. They should be determined by
gdbarch.
gdb:
2016-11-03 Yao Qi <yao.qi@linaro.org>
* arch-utils.h (GDBARCH_BREAKPOINT_MANIPULATION): Define
breakpoint_kind_from_pc and sw_breakpoint_from_kind.
(GDBARCH_BREAKPOINT_MANIPULATION_ENDIAN): Likewise.
(SET_GDBARCH_BREAKPOINT_MANIPULATION): Call
set_gdbarch_breakpoint_kind_from_pc and
set_gdbarch_sw_breakpoint_from_kind.
* arm-tdep.c: Add comments.
* bfin-tdep.c: Likewise.
* breakpoint.c (breakpoint_kind): New function.
(insert_bp_location): Set target_info.placed_size and
target_info.placed_address.
(bkpt_insert_location): Likewise.
* cris-tdep.c: Add comments.
* gdbarch.sh (breakpoint_kind_from_pc): New.
(sw_breakpoint_from_kind): New.
* gdbarch.c, gdbarch.h: Regenerated.
* ia64-tdep.c (ia64_memory_insert_breakpoint): Don't set
bp_tgt->placed_size.
(ia64_memory_remove_breakpoint): Don't assert
bp_tgt->placed_size.
(ia64_breakpoint_kind_from_pc): New function.
(ia64_gdbarch_init): Install ia64_breakpoint_kind_from_pc.
* m32r-tdep.c (m32r_memory_insert_breakpoint): Don't set
bp_tgt->placed_size.
* mem-break.c (default_memory_insert_breakpoint): Don't set
bp_tgt->placed_size. Call gdbarch_sw_breakpoint_from_kind.
(default_memory_remove_breakpoint): Call
gdbarch_sw_breakpoint_from_kind.
(memory_validate_breakpoint): Don't check bp_tgt->placed_size.
* mips-tdep.c: Add comments.
* mt-tdep.c: Likewise.
* nios2-tdep.c: Likewise.
* record-full.c (record_full_insert_breakpoint): Don't call
gdbarch_breakpoint_from_pc. Don't set bp_tgt->placed_address
and bp_tgt->placed_size.
* remote.c (remote_insert_breakpoint): Don't call
gdbarch_remote_breakpoint_from_pc. Use bp_tgt->placed_size.
Don't set bp_tgt->placed_address and bp_tgt->placed_size.
(remote_insert_hw_breakpoint): Likewise.
* score-tdep.c: Likewise.
* sh-tdep.c: Likewise.
* tic6x-tdep.c: Likewise.
* v850-tdep.c: Likewise.
* xtensa-tdep.c: Likewise.
This removes make_cleanup_restore_current_ui by converting the last
use. The last use was in a few functions used to iterate over all
UIs. This patch replaces these functions with a class, and arranges
for the class destructor to do the needed cleanup.
2016-10-21 Tom Tromey <tom@tromey.com>
* tui/tui-interp.c (tui_on_normal_stop, tui_on_signal_received)
(tui_on_end_stepping_range, tui_on_signal_exited, tui_on_exited)
(tui_on_no_history, tui_on_user_selected_context_changed):
Update.
* top.h (switch_thru_all_uis): New class.
(SWITCH_THRU_ALL_UIS): Rewrite.
(make_cleanup_restore_current_ui, switch_thru_all_uis_init)
(switch_thru_all_uis_cond, switch_thru_all_uis_next): Don't
declare.
* mi/mi-interp.c (mi_new_thread, mi_thread_exit)
(mi_record_changed, mi_inferior_added, mi_inferior_appeared)
(mi_inferior_exit, mi_inferior_removed, mi_on_signal_received)
(mi_on_end_stepping_range, mi_on_signal_exited, mi_on_exited)
(mi_on_no_history, mi_on_normal_stop, mi_traceframe_changed)
(mi_tsv_created, mi_tsv_deleted, mi_tsv_modified)
(mi_breakpoint_created, mi_breakpoint_deleted)
(mi_breakpoint_modified, mi_output_running_pid, mi_on_resume)
(mi_solib_loaded, mi_solib_unloaded, mi_command_param_changed)
(mi_memory_changed, mi_user_selected_context_changed): Update.
* infrun.c (all_uis_check_sync_execution_done)
(all_uis_on_sync_execution_starting, normal_stop): Update.
* event-top.c (restore_ui_cleanup)
(make_cleanup_restore_current_ui, switch_thru_all_uis_init)
(switch_thru_all_uis_cond, switch_thru_all_uis_next): Remove.
* cli/cli-interp.c (cli_on_normal_stop, cli_on_signal_received)
(cli_on_end_stepping_range, cli_on_signal_exited, cli_on_exited)
(cli_on_no_history, cli_on_user_selected_context_changed):
Update.
* breakpoint.c (watchpoint_check): Update.
This converts tid_range_parser and get_number_or_range to be classes.
The various tid_range_parser_* and get_number_or_range_* functions
become methods on the respective classes. Then it updates the users
to follow.
The rationale for the change is that this provides better
encapsulation. For example, this forced me to think of a better
interface between tid_range_parser and get_number_or_range, since the
former peeked into the latter's internals a bit too much. That ended
up resulting mostly in these two not-just-straight-1-1 changes:
void
-tid_range_parser_skip (struct tid_range_parser *parser)
+tid_range_parser::skip_range ()
{
...
- tid_range_parser_init (parser, parser->range_parser.end_ptr,
- parser->default_inferior);
+ m_range_parser.skip_range ();
+ init (m_range_parser.string (), m_default_inferior);
}
and:
/* If we successfully parsed a thread number or finished parsing a
thread range, switch back to assuming the next TID is
inferior-qualified. */
- if (parser->range_parser.end_ptr == NULL
- || parser->range_parser.string == parser->range_parser.end_ptr)
+ if (!m_range_parser.in_range ())
{
For the same reason (encapsulation), this moves the enum
tid_range_state definition to within the tid_parser class's scope,
since that is private implementation detail.
While at it, switch to use "bool" for booleans.
gdb/ChangeLog:
2016-10-13 Pedro Alves <palves@redhat.com>
Tom Tromey <tom@tromey.com>
* tid-parse.h (tid_range_parser): New class.
(enum tid_range_state): Move into tid_range_parser's scope.
Remove TID_RANGE_ prefix from all values.
(tid_range_parser_get_tid, tid_range_parser_get_tid_range)
(tid_range_parser_star_range, tid_range_parser_finished)
(tid_range_parser_skip, tid_range_parser_qualified): Don't
declare.
(tid_is_in_list): Update comment.
* tid-parse.c (tid_range_parser::tid_range_parser): New.
(init, finished, get_string, skip, tid_is_qualified)
(get_tid_or_range, get_tid_range, get_tid, star_range): Rename;
turn into methods.
(tid_is_in_list): Adjust.
* cli/cli-utils.h (number_or_range_parser): New class.
(init_number_or_range, get_number_or_range)
(number_range_setup_range): Don't declare.
* cli/cli-utils.c
(number_or_range_parser::number_or_range_parser): New.
(init_number_or_range, get_number_or_range)
(number_range_setup_range): Rename; turn into methods.
(number_is_in_list): Adjust.
* breakpoint.c (map_breakpoint_numbers): Adjust. Use bool.
(trace_pass_command, get_tracepoint_by_number): Adjust.
* breakpoint.h (get_tracepoint_by_number): Adjust.
* inferior.c (detach_inferior_command, kill_inferior_command)
(remove_inferior_command): Adjust.
* linespec.c (decode_line_2): Adjust.
* memattr.c (mem_enable_command, mem_disable_command)
(mem_delete_command): Adjust.
* printcmd.c (map_display_numbers): Adjust.
* reverse.c (delete_bookmark_command, bookmarks_info): Adjust.
* thread.c (thread_apply_command): Adjust.
Building on a 32-bit host fails currently with errors like:
.../src/gdb/exec.c: In function ‘target_xfer_status section_table_read_available_memory(gdb_byte*, ULONGEST, ULONGEST, ULONGEST*)’:
.../src/gdb/exec.c:801:54: error: no matching function for call to ‘min(ULONGEST, long unsigned int)’
end = std::min (offset + len, r->start + r->length);
^
In file included from /usr/include/c++/5.3.1/algorithm:61:0,
from .../src/gdb/exec.c:46:
/usr/include/c++/5.3.1/bits/stl_algobase.h:195:5: note: candidate: template<class _Tp> const _Tp& std::min(const _Tp&, const _Tp&)
min(const _Tp& __a, const _Tp& __b)
^
/usr/include/c++/5.3.1/bits/stl_algobase.h:195:5: note: template argument deduction/substitution failed:
.../src/gdb/exec.c:801:54: note: deduced conflicting types for parameter ‘const _Tp’ (‘long long unsigned int’ and ‘long unsigned int’)
end = std::min (offset + len, r->start + r->length);
^
In file included from /usr/include/c++/5.3.1/algorithm:61:0,
from .../src/gdb/exec.c:46:
/usr/include/c++/5.3.1/bits/stl_algobase.h:243:5: note: candidate: template<class _Tp, class _Compare> const _Tp& std::min(const _Tp&, const _Tp&, _Compare)
min(const _Tp& __a, const _Tp& __b, _Compare __comp)
^
The problem is that the std::min/std::max function templates use the
same type for both parameters. When the argument types are different,
the compiler can't automatically deduce which template specialization
to pick from the arguments' types.
Fix that by specifying the specialization we want explicitly.
gdb/ChangeLog:
2016-09-18 Pedro Alves <palves@redhat.com>
* breakpoint.c (hardware_watchpoint_inserted_in_range): Explicitly
specify the std:min/std::max specialization.
* exec.c (section_table_read_available_memory): Likewise.
* remote.c (remote_read_qxfer): Likewise.
* target.c (simple_verify_memory): Likewise.
Makes the code more obvious.
gdb/ChangeLog:
2016-08-10 Pedro Alves <palves@redhat.com>
PR gdb/19187
* breakpoint.c (insertion_state_t): Delete.
(enum remove_bp_reason): New.
(detach_breakpoints, remove_breakpoint_1, remove_breakpoint):
Adjust to use enum remove_bp_reason instead of insertion_state_t.
All callers pass mark_uninserted, so there's no need for the 'is'
parameter.
gdb/ChangeLog:
2016-08-10 Pedro Alves <palves@redhat.com>
PR gdb/19187
* breakpoint.c (remove_breakpoint): Remove 'is' parameter and
always pass mark_uninserted to remove_breakpoint_1.
(insert_breakpoint_locations, remove_breakpoints)
(remove_breakpoints_pid, update_global_location_list): Update
callers.
This patch adds a "pending" attribute to gdb.Breakpoint.
Built and regtested on x86-64 Fedora 23.
2016-07-13 Tom Tromey <tom@tromey.com>
PR python/17698:
* NEWS: Update.
* python/py-breakpoint.c (bppy_get_pending): New function.
(breakpoint_object_getset): Add entry for "pending".
* breakpoint.h (pending_breakpoint_p): Declare.
* breakpoint.c (pending_breakpoint_p): New function.
2016-07-13 Tom Tromey <tom@tromey.com>
PR python/17698:
* python.texi (Breakpoints In Python): Document
Breakpoint.pending.
2016-07-13 Tom Tromey <tom@tromey.com>
PR python/17698:
* gdb.python/py-breakpoint.exp (test_bkpt_basic): Add "pending"
test.
(test_watchpoints): Likewise.
(test_bkpt_pending): New proc.
If you have two inferiors (or more), set watchpoints in one of the
inferiors, and then that inferior exits, until you manually delete the
watchpoint (or something forces a breakpoint re-set), you can't resume
the other inferior.
This is exercised by the test added by this commit. Without the GDB
fix, this test fails like this:
FAIL: gdb.multi/watchpoint-multi-exit.exp: dispose=kill: continue to marker in inferior 1
FAIL: gdb.multi/watchpoint-multi-exit.exp: dispose=detach: continue to marker in inferior 1
FAIL: gdb.multi/watchpoint-multi-exit.exp: dispose=exit: continue to marker in inferior 1
and gdb.log shows (in all three cases):
(gdb) continue
Continuing.
Warning:
Could not insert hardware watchpoint 2.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.
Command aborted.
(gdb) FAIL: gdb.multi/watchpoint-multi-exit.exp: dispose=kill: continue to marker in inferior 1
The problem is that GDB doesn't forget about the locations of
watchpoints set in the inferior that is now dead. When we try to
continue the inferior that is still alive, we reach
insert_breakpoint_locations, which has the the loop that triggers the
error:
/* If we failed to insert all locations of a watchpoint, remove
them, as half-inserted watchpoint is of limited use. */
That loop finds locations that are not marked inserted, but which
according to should_be_inserted should have been inserted, and so
errors out.
gdb/ChangeLog:
2016-07-01 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoint_init_inferior): Discard watchpoint
locations.
* infcmd.c (detach_command): Call breakpoint_init_inferior.
gdb/testsuite/ChangeLog:
2016-07-01 Pedro Alves <palves@redhat.com>
* gdb.multi/watchpoint-multi-exit.c: New file.
* gdb.multi/watchpoint-multi-exit.exp: New file.
Testing with:
make check RUNTESTFLAGS="SEPARATE_MI_TTY=1"
shows this, in gdb.mi/mi-watch.exp:
-*stopped,reason="watchpoint-scope",wpnum="2",frame={addr="0x00000000004005cb",
+*stopped,frame={addr="0x00000000004005cb",
(...)
-PASS: gdb.mi/mi-watch.exp: hw: watchpoint trigger
+FAIL: gdb.mi/mi-watch.exp: hw: watchpoint trigger (unknown output after running)
That is, we lose the "watchpoint-scope" output on the MI UI.
This commit fixes it, and makes the test run with MI running as both
main UI and separate UI.
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* breakpoint.c (watchpoint_check): Send watchpoint-deleted output
to all UIs.
gdb/testsuite/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* gdb.mi/mi-watch.exp (test_watchpoint_creation_and_listing)
(test_awatch_creation_and_listing)
(test_rwatch_creation_and_listing, test_watchpoint_triggering):
Remove 'type' parameter.
(test_watchpoint_all): New parameter mi_mode. Remove
with_test_prefix.
(top level): Use foreach_with_prefix, and add main/separate UI MI
testing axis.
I noticed that if we step into an inline function, step_1 never
reaches proceed, and thus nevers sets the thread's
tp->control.command_interp. Because of that,
should_print_stop_to_console fails to determine that is should print
stop output to the console.
The fix is to set the thread's command_interp earlier. However, I
realized that we can move that field to the thread_fsm, given that its
lifetime is exactly the same as thread_fsm. So the patch plumbs all
fsms constructors to take the command interp and store it in the
thread_fsm.
We can see the fix in action, with e.g., the gdb.opt/inline-cmds.exp
test, and issuing a step when stopped at line 67:
&"s\n"
^running
*running,thread-id="all"
(gdb)
~"67\t result = func2 ();\n"
*stopped,reason="end-stepping-range",frame={addr="0x00000000004004d0",func="main",args=[],file="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.opt/inline-cmds.c",fullname="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.opt/inline-cmds.c",line="67"},thread-id="1",stopped-threads="all",core="0"
(gdb)
s
&"s\n"
^running
*running,thread-id="all"
(gdb)
+ ~"func2 () at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.opt/inline-cmds.c:67\n"
+ ~"67\t result = func2 ();\n"
*stopped,reason="end-stepping-range",frame={addr="0x00000000004004d0",func="func2",args=[],file="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.opt/inline-cmds.c",fullname="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.opt/inline-cmds.c",line="67"},thread-id="1",stopped-threads="all",core="0"
(gdb)
(The inline-cmds.exp command is adjusted to exercise this.)
(Due to the follow_fork change, this also fixes "next N" across a fork
with "set follow-fork child" with "set detach-on-fork on". Commands
that rely on internal breakpoints, like "finish" will still require
more work to migrate breakpoints etc. to the child thread.)
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* breakpoint.c (new_until_break_fsm): Add 'cmd_interp' parameter.
(until_break_fsm_should_stop, until_break_fsm_clean_up): Add
thread parameter.
(until_break_command): Pass command interpreter to thread fsm
ctor.
* cli/cli-interp.c (should_print_stop_to_console): Adjust.
* gdbthread.h (struct thread_control_state) <command_interp>:
Delete field.
* infcall.c (new_call_thread_fsm): Add 'cmd_interp' parameter.
Pass it down.
(call_thread_fsm_should_stop): Add thread parameter.
(call_function_by_hand_dummy): Pass command interpreter to thread
fsm ctor. Pass thread pointer to fsm clean up method.
* infcmd.c: Include interps.h.
(struct step_command_fsm) <thread>: Delete field.
(new_step_command_fsm): Add 'cmd_interp' parameter. Pass it down.
(step_command_fsm_prepare): Remove references to fsm's thread
field.
(step_1): Pass command interpreter to thread
fsm ctor. Pass thread pointer to fsm clean up method.
(step_command_fsm_should_stop, step_command_fsm_clean_up): Add
thread parameter and use it.
(new_until_next_fsm): Add 'cmd_interp' parameter. Pass it down.
(until_next_fsm_should_stop, until_next_fsm_clean_up): Add thread
parameter and use it.
(until_next_command): Pass command interpreter to thread fsm ctor.
(struct finish_command_fsm) <thread>: Delete field.
(finish_command_fsm_ops): Add NULL slot for should_notify_stop.
(new_finish_command_fsm): Add 'cmd_interp' parameter and pass it
down. Remove thread parameter and adjust.
(finish_command_fsm_should_stop, finish_command_fsm_clean_up): Add
thread parameter and use it.
(finish_command): Pass command interpreter to thread fsm ctor.
Don't pass thread.
* infrun.c (follow_fork): Move thread fsm to child fork instead of
command interpreter, only.
(clear_proceed_status_thread): Remove reference to command_interp.
(proceed): Don't record the thread's command interpreter.
(clean_up_just_stopped_threads_fsms): Pass thread to fsm clean_up
method.
(fetch_inferior_event): Pass thread to fsm should_stop method.
* thread-fsm.c (thread_fsm_ctor): Add 'cmd_interp' parameter.
Store it.
(thread_fsm_clean_up, thread_fsm_should_stop): Add thread
parameter and pass it down.
* thread-fsm.h (struct thread_fsm) <command_interp>: New field.
(struct thread_fsm_ops) <clean_up, should_stop>: Add thread
parameter.
(thread_fsm_ctor): Add 'cmd_interp' parameter.
(thread_fsm_clean_up, thread_fsm_should_stop): Add thread
parameter.
* thread.c (thread_cancel_execution_command): Pass thread to
thread fsm clean_up method.
gdb/testsuite/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* gdb.opt/inline-cmds.c: Add "set mi break here" marker.
* gdb.opt/inline-cmds.exp: Add MI tests.
Make each UI have its own interpreter list, top level interpreter,
current interpreter, etc. The "interpreter_async" global is not
really specific to an struct interp (it crosses interpreter-exec ...),
so I moved it to "struct ui" directly, while the other globals were
left hidden in interps.c, opaque to the rest of GDB.
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_do_actions_1): Access the current UI's
async field instead of the interpreter_async global.
* cli/cli-script.c (execute_user_command, while_command)
(if_command, script_from_file): Likewise.
* compile/compile.c: Include top.h instead of interps.h.
(compile_file_command, compile_code_command)
(compile_print_command): Access the current UI's async field
instead of the interpreter_async global.
* guile/guile.c: Include top.h instead of interps.h.
(guile_repl_command, guile_command, gdbscm_execute_gdb_command):
Access the current UI's async field instead of the
interpreter_async global.
* guile/scm-ports.c: Include top.h instead of interps.h.
(ioscm_with_output_to_port_worker): Access the current UI's async
field instead of the interpreter_async global.
* inf-loop.c (inferior_event_handler): Likewise.
* infcall.c (run_inferior_call): Likewise.
* infrun.c (reinstall_readline_callback_handler_cleanup)
(fetch_inferior_event): Likewise.
* interps.c (interpreter_async): Delete.
(struct ui_interp_info): New.
(get_current_interp_info): New function.
(interp_list, current_interpreter, top_level_interpreter_ptr):
Delete.
(interp_add, interp_set, interp_lookup, interp_ui_out)
(current_interp_set_logging, interp_set_temp)
(current_interp_named_p): Adjust to per-UI interpreters.
(command_interpreter): Delete.
(command_interp, current_interp_command_loop, interp_quiet_p)
(interp_exec, interpreter_exec_cmd, interpreter_completer)
(top_level_interpreter, top_level_interpreter_data): Adjust to
per-UI interpreters.
* interps.h (interpreter_async): Delete.
* main.c (captured_command_loop): Access the current UI's async
field instead of the interpreter_async global.
* python/python.c (python_interactive_command, python_command)
(execute_gdb_command): Likewise.
* top.c (maybe_wait_sync_command_done, execute_command_to_string):
Access the current UI's async field instead of the
interpreter_async global.
* top.h (struct tl_interp_info): Forward declare.
(struct ui) <interp_info, async>: New fields.
GDB doesn't insert software single step breakpoint if the instruction
branches to itself, so that the program can't stop after command "si".
(gdb) b 32
Breakpoint 2 at 0x8680: file git/gdb/testsuite/gdb.base/branch-to-self.c, line 32.
(gdb) c
Continuing.
Breakpoint 2, main () at gdb/git/gdb/testsuite/gdb.base/branch-to-self.c:32
32 asm (".Lhere: " BRANCH_INSN " .Lhere"); /* loop-line */
(gdb) si
infrun: clear_proceed_status_thread (Thread 3991.3991)
infrun: proceed (addr=0xffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: step-over queue now empty
infrun: resuming [Thread 3991.3991] for step-over
infrun: skipping breakpoint: stepping past insn at: 0x8680
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Sending packet: $Z0,8678,4#f3...Packet received: OK
infrun: skipping breakpoint: stepping past insn at: 0x8680
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Sending packet: $Z0,b6fe86c8,4#82...Packet received: OK
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=1, current thread [Thread 3991.3991] at 0x868
breakpoint.c:should_be_inserted thinks the breakpoint shouldn't be
inserted, which is wrong. This patch restrict the condition that
only skip the non-single-step breakpoints if they are inserted at
the place we are stepping over, however we don't want to skip
single-step breakpoint if its thread is the thread we are stepping
over, so in this patch, I add a thread num in 'struct step_over_info'
to record the thread we're stepping over.
gdb:
2016-04-25 Yao Qi <yao.qi@linaro.org>
* breakpoint.c (should_be_inserted): Return 0 if the location's
owner is not single step breakpoint or single step breakpoint's
thread isn't the thread which is stepping past a breakpoint.
* gdbarch.sh (software_single_step): Update comments.
* gdbarch.h: Regenerated.
* infrun.c (struct step_over_info) <thread>: New field.
(set_step_over_info): New argument 'thread'. Callers updated.
(clear_step_over_info): Set field thread to -1.
(thread_is_stepping_over_breakpoint): New function.
* infrun.h (thread_is_stepping_over_breakpoint): Declaration.
One of the last checks update_breakpoints_after_exec does while looping
over the list of breakpoints is check that the breakpoint has a valid
location spec. It uses event_location_empty_p to check if the location spec
is "empty", and if it is, the breakpoint is deleted.
momentary_breakpoint types rely on setting the breakpoint structure's
location spec to NULL, thereby causing an update to delete the breakpoint.
However, event_location_empty_p assumed that locations were never NULL.
As a result, GDB would crash dereferencing a NULL pointer whenever
update_breakpoints_after_exec would encounter a momentary_breakpoint.
This patch creates a new wrapper/helper function which tests that the given
breakpoint's location spec is non-NULL and if it is not "empty"
or "unspecified."
gdb/ChangeLog
PR breakpoints/19546
* breakpoint.c (breakpoint_event_location_empty_p): New function.
(update_breakpoints_after_exec, bkpt_re_set): Use this new function
instead of event_location_empty_p.
gdb/testsuite/ChangeLog
PR breakpoints/19546
* gdb.base/infcall-exec.c: New file.
* gdb.base/infcall-exec2.c: New file.
* gdb.base/infcall-exec.exp: New file.
PR19548 shows that we still have problems related to 13fd3ff34329:
[PR17431: following execs with "breakpoint always-inserted on"]
https://sourceware.org/ml/gdb-patches/2014-09/msg00733.html
The problem this time is that we currently update the global location
list and try to insert breakpoint locations after re-setting _each_
breakpoint in turn.
Say:
- We have _more_ than one breakpoint set. Let's assume 2.
- There's a breakpoint with a pre-exec address that ends up being an
unmapped address after the exec.
- That breakpoint is NOT the first in the breakpoint list.
Then when handling an exec, and we re-set the first breakpoint in the
breakpoint list, we mistakently try to install the old pre-exec /
un-re-set locations of the other breakpoint, which fails:
(gdb) continue
Continuing.
process 28295 is executing new program: (...)/execl-update-breakpoints2
Error in re-setting breakpoint 1: Warning:
Cannot insert breakpoint 2.
Cannot access memory at address 0x1000764
Breakpoint 1, main (argc=1, argv=0x7fffffffd368) at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/execl-update-breakpoints.c:34
34 len = strlen (argv[0]);
(gdb)
Fix this by deferring the global location list update till after all
breakpoints are re-set.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
2016-02-09 Pedro Alves <palves@redhat.com>
PR breakpoints/19548
* breakpoint.c (create_overlay_event_breakpoint): Don't update
global location list here.
(create_longjmp_master_breakpoint)
(create_std_terminate_master_breakpoint)
(create_exception_master_breakpoint, create_jit_event_breakpoint)
(update_breakpoint_locations):
(breakpoint_re_set): Update global location list after all
breakpoints are re-set.
gdb/testsuite/ChangeLog:
2016-02-09 Pedro Alves <palves@redhat.com>
PR breakpoints/19548
* gdb.base/execl-update-breakpoints.c (some_function): New
function.
(main): Call it.
* gdb.base/execl-update-breakpoints.exp: Add a second breakpoint.
Tighten expected GDB output.
I see GDB crashes in dprintf.exp on aarch64-linux testing,
(gdb) PASS: gdb.base/dprintf.exp: agent: break 29
set dprintf-style agent^M
(gdb) PASS: gdb.base/dprintf.exp: agent: set dprintf style to agent
continue^M
Continuing.
ASAN:SIGSEGV
=================================================================
==22475==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000008 (pc 0x000000494820 sp 0x7fff389b83a0 bp 0x62d000082417 T0)
#0 0x49481f in remote_add_target_side_commands /home/yao/SourceCode/gnu/gdb/git/gdb/remote.c:9190^M
#1 0x49e576 in remote_add_target_side_commands /home/yao/SourceCode/gnu/gdb/git/gdb/remote.c:9174^M
#2 0x49e576 in remote_insert_breakpoint /home/yao/SourceCode/gnu/gdb/git/gdb/remote.c:9240^M
#3 0x5278b7 in insert_bp_location /home/yao/SourceCode/gnu/gdb/git/gdb/breakpoint.c:2734^M
#4 0x52ac09 in insert_breakpoint_locations /home/yao/SourceCode/gnu/gdb/git/gdb/breakpoint.c:3159^M
#5 0x52ac09 in update_global_location_list /home/yao/SourceCode/gnu/gdb/git/gdb/breakpoint.c:12686
the root cause of this problem in this case is about linespec and
symtab which produces additional incorrect location and a NULL is added to
bp_tgt->tcommands. I posted a patch
https://sourceware.org/ml/gdb-patches/2015-12/msg00321.html to fix it
in linespec (the fix causes regression), but GDB still shouldn't add
NULL into bp_tgt->tcommands. The logic of build_target_command_list
looks odd to me. If we get something wrong in parse_cmd_to_aexpr (it
returns NULL), we shouldn't continue, instead we should set flag
null_command_or_parse_error. This is what this patch does. In the
meantime, we find build_target_condition_list has the same problem, so
fix it too.
gdb:
2016-01-28 Yao Qi <yao.qi@linaro.org>
* breakpoint.c (build_target_command_list): Don't call continue
if aexpr is NULL.
(build_target_condition_list): Likewise.
A relatively recent patch support for explicit locations, and part
of that patch cleaned up the way we parse breakpoint locations.
Unfortunatly, a small regression crept in for "*<EXPR>" breakpoint
locations. In particular, on PIE programs, one can see the issue by
doing the following, with any program:
(gdb) b *main
Breakpoint 1 at 0x51a: file hello.c, line 3.
(gdb) run
Starting program: /[...]/hello
Error in re-setting breakpoint 1: Warning:
Cannot insert breakpoint 1.
Cannot access memory at address 0x51a
Warning:
Cannot insert breakpoint 1.
Cannot access memory at address 0x51a
Just for the record, this regression was introduced by:
commit a06efdd6ef
Date: Tue Aug 11 17:09:35 2015 -0700
Subject: Explicit locations: introduce address locations
What happens is that the patch makes the implicit assumption that
the address computed the first time is static, as if it was designed
to only support litteral expressions (Eg. "*0x1234"). This allows
the shortcut of not re-computing the breakpoint location's address
when re-setting breakpoints.
However, this does not work in general, as demonstrated in the example
above.
This patch plugs that hole simply by saving the original expression
used to compute the address as part of the address location, so as
to then re-evaluate that expression during breakpoint re-set.
gdb/ChangeLog:
* location.h (new_address_location): Add new parameters
"addr_string" and "addr_string_len".
(get_address_string_location): Add declaration.
* location.c (new_address_location): Add new parameters
"addr_string" and "addr_string_len". If not NULL, store
a copy of the addr_string in the new location as well.
(get_address_string_location): New function.
(string_to_event_location): Update call to new_address_location.
* linespec.c (event_location_to_sals) <ADDRESS_LOCATION>:
Save the event location in the parser's state before
passing it to convert_address_location_to_sals.
* breakpoint.c (create_thread_event_breakpoint): Update call
to new_address_location.
(init_breakpoint_sal): Get the event location's string, if any,
and use it to update call to new_address_location.
* python/py-finishbreakpoint.c (bpfinishpy_init):
Update call to new_address_location.
* spu-tdep.c (spu_catch_start): Likewise.
* config/djgpp/fnchange.lst: Add entries for
gdb/testsuite/gdb.base/break-fun-addr1.c and
gdb/testsuite/gdb.base/break-fun-addr2.c.
gdb/testsuite/ChangeLog:
* gdb.base/break-fun-addr.exp: New file.
* gdb.base/break-fun-addr1.c: New file.
* gdb.base/break-fun-addr2.c: New file.
Currently, we always re-set all locations of all breakpoints. This
commit makes us re-set only locations of the current program space.
If we loaded symbols to a program space (e.g., "file" command or some
shared library was loaded), GDB must run through all breakpoints and
determine if any new locations need to be added to the breakpoint.
However, there's no reason to recreate locations for _other_ program
spaces, as those haven't changed.
Similarly, when we create a new inferior, through e.g., a fork, GDB
must run through all breakpoints and determine if any new locations
need to be added to the breakpoint. There's no reason to destroy the
locations of the parent inferior and other inferiors. We know those
won't change.
In addition to being inneficient, resetting breakpoints of inferiors
that are currently running is problematic, because:
- some targets can't read memory while the inferior is running.
- the inferior might exit while we're re-setting its breakpoints,
which may confuse prologue skipping.
I went through all the places where we call breakpoint_re_set, and it
seems to me that all can be changed to only re-set locations of the
current program space.
The patch that reversed threads order in "info threads" etc. happened
to make gdb.threads/fork-plus-thread.exp expose this problem when
testing on x86/-m32. The problem was latent and masked out by chance
by the code-cache:
https://sourceware.org/ml/gdb-patches/2016-01/msg00213.html
Tested on x86-64 F20, native (-m64/-m32) and extended-remote
gdbserver.
Fixes the regression discussed in the url above with --target_board=unix/-m32:
-FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: inferior 1 exited
+PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: inferior 1 exited
-FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: no threads left (timeout)
-FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: only inferior 1 left (the program exited)
+PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: no threads left
+PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: only inferior 1 left
gdb/ChangeLog:
2016-01-19 Pedro Alves <palves@redhat.com>
* ax-gdb.c (agent_command_1): Adjust call to decode_line_full.
* break-catch-throw.c (re_set_exception_catchpoint): Pass the
current program space down to linespec decoding and breakpoint
location updating.
* breakpoint.c (parse_breakpoint_sals): Adjust calls to
decode_line_full.
(until_break_command): Adjust calls to decode_line_1.
(base_breakpoint_decode_location, bkpt_decode_location): Add
'search_pspace' parameter. Pass it along.
(bkpt_probe_create_sals_from_location): Adjust calls to
parse_probes.
(tracepoint_decode_location, tracepoint_probe_decode_location)
(strace_marker_decode_location): Add 'search_pspace' parameter.
Pass it along.
(all_locations_are_pending): Rewrite to take a breakpoint and
program space as arguments instead.
(hoist_existing_locations): New function.
(update_breakpoint_locations): Add 'filter_pspace' parameter. Use
hoist_existing_locations instead of always removing all locations,
and adjust to all_locations_are_pending change.
(location_to_sals): Add 'search_pspace' parameter. Pass it along.
Don't disable the breakpoint if there are other locations in
another program space.
(breakpoint_re_set_default): Adjust to pass down the current
program space as filter program space.
(decode_location_default): Add 'search_pspace' parameter and pass
it along.
(prepare_re_set_context): Don't switch program space here.
(breakpoint_re_set): Use save_current_space_and_thread instead of
save_current_program_space.
* breakpoint.h (struct breakpoint_ops) <decode_location>: Add
'search_pspace' parameter.
(update_breakpoint_locations): Add 'filter_pspace' parameter.
* cli/cli-cmds.c (edit_command, list_command): Adjust calls to
decode_line_1.
* elfread.c (elf_gnu_ifunc_resolver_return_stop): Pass the current
program space as filter program space.
* linespec.c (struct linespec_state) <search_pspace>: New field.
(create_sals_line_offset, convert_explicit_location_to_sals)
(parse_linespec): Pass the search program space down.
(linespec_state_constructor): Add 'search_pspace' parameter.
Store it.
(linespec_parser_new): Add 'search_pspace' parameter and pass it
along.
(linespec_lex_to_end): Adjust.
(decode_line_full, decode_line_1): Add 'search_pspace' parameter
and pass it along.
(decode_line_with_last_displayed): Adjust.
(collect_symtabs_from_filename, symtabs_from_filename): New
'search_pspace' parameter. Use it.
(find_function_symbols): Pass the search program space down.
* linespec.h (decode_line_1, decode_line_full): Add
'search_pspace' parameter.
* probe.c (parse_probes_in_pspace): New function, factored out
from ...
(parse_probes): ... this. Add 'search_pspace' parameter and use
it.
* probe.h (parse_probes): Add pspace' parameter.
* python/python.c (gdbpy_decode_line): Adjust.
* tracepoint.c (scope_info): Adjust.
This commit changes GDB like this:
- Program received signal SIGINT, Interrupt.
+ Thread 1 "main" received signal SIGINT, Interrupt.
- Breakpoint 1 at 0x40087a: file threads.c, line 87.
+ Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file threads.c, line 87.
... once the program goes multi-threaded. Until GDB sees a second
thread spawn, the output is still the same as before, per the
discussion back in 2012:
https://www.sourceware.org/ml/gdb/2012-11/msg00010.html
This helps non-stop mode, where you can't easily tell which thread hit
a breakpoint or received a signal:
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fc1740 (LWP 19362) "main" (running)
2 Thread 0x7ffff7fc0700 (LWP 19366) "foo" (running)
3 Thread 0x7ffff77bf700 (LWP 19367) "bar" (running)
(gdb)
Program received signal SIGUSR1, User defined signal 1.
0x0000003616a09237 in pthread_join (threadid=140737353877248, thread_return=0x7fffffffd5b8) at pthread_join.c:92
92 lll_wait_tid (pd->tid);
(gdb) b threads.c:87
Breakpoint 1 at 0x40087a: file threads.c, line 87.
(gdb)
Breakpoint 1, thread_function1 (arg=0x1) at threads.c:87
87 usleep (1); /* Loop increment. */
The best the user can do is run "info threads" and try to figure
things out.
It actually also affects all-stop mode, in case of "handle SIG print
nostop":
...
Program received signal SIGUSR1, User defined signal 1.
Program received signal SIGUSR1, User defined signal 1.
Program received signal SIGUSR1, User defined signal 1.
Program received signal SIGUSR1, User defined signal 1.
...
The above doesn't give any clue that these were different threads
getting the SIGUSR1 signal.
I initially thought of lowercasing "breakpoint" in
"Thread 3 hit Breakpoint 1"
but then after trying it I realized that leaving "Breakpoint"
uppercase helps the eye quickly find the relevant information. It's
also easier to implement not showing anything about threads until the
program goes multi-threaded this way.
Here's a larger example session in non-stop mode:
(gdb) c -a&
Continuing.
(gdb) interrupt -a
(gdb)
Thread 1 "main" stopped.
0x0000003616a09237 in pthread_join (threadid=140737353877248, thread_return=0x7fffffffd5b8) at pthread_join.c:92
92 lll_wait_tid (pd->tid);
Thread 2 "foo" stopped.
0x0000003615ebc6ed in nanosleep () at ../sysdeps/unix/syscall-template.S:81
81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
Thread 3 "bar" stopped.
0x0000003615ebc6ed in nanosleep () at ../sysdeps/unix/syscall-template.S:81
81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
b threads.c:87
Breakpoint 4 at 0x40087a: file threads.c, line 87.
(gdb) b threads.c:67
Breakpoint 5 at 0x400811: file threads.c, line 67.
(gdb) c -a&
Continuing.
(gdb)
Thread 3 "bar" hit Breakpoint 4, thread_function1 (arg=0x1) at threads.c:87
87 usleep (1); /* Loop increment. */
Thread 2 "foo" hit Breakpoint 5, thread_function0 (arg=0x0) at threads.c:68
68 (*myp) ++;
info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fc1740 (LWP 31957) "main" (running)
2 Thread 0x7ffff7fc0700 (LWP 31961) "foo" thread_function0 (arg=0x0) at threads.c:68
3 Thread 0x7ffff77bf700 (LWP 31962) "bar" thread_function1 (arg=0x1) at threads.c:87
(gdb) shell kill -SIGINT 31957
(gdb)
Thread 1 "main" received signal SIGINT, Interrupt.
0x0000003616a09237 in pthread_join (threadid=140737353877248, thread_return=0x7fffffffd5b8) at pthread_join.c:92
92 lll_wait_tid (pd->tid);
info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fc1740 (LWP 31957) "main" 0x0000003616a09237 in pthread_join (threadid=140737353877248, thread_return=0x7fffffffd5b8) at pthread_join.c:92
2 Thread 0x7ffff7fc0700 (LWP 31961) "foo" thread_function0 (arg=0x0) at threads.c:68
3 Thread 0x7ffff77bf700 (LWP 31962) "bar" thread_function1 (arg=0x1) at threads.c:87
(gdb) t 2
[Switching to thread 2, Thread 0x7ffff7fc0700 (LWP 31961)]
#0 thread_function0 (arg=0x0) at threads.c:68
68 (*myp) ++;
(gdb) catch syscall
Catchpoint 6 (any syscall)
(gdb) c&
Continuing.
(gdb)
Thread 2 "foo" hit Catchpoint 6 (call to syscall nanosleep), 0x0000003615ebc6ed in nanosleep () at ../sysdeps/unix/syscall-template.S:81
81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
I'll work on documentation next if this looks agreeable.
This patch applies on top of the star wildcards thread IDs series:
https://sourceware.org/ml/gdb-patches/2016-01/msg00291.html
For convenience, I've pushed this to the
users/palves/show-which-thread-caused-stop branch.
gdb/doc/ChangeLog:
2016-01-18 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Threads): Mention that GDB displays the ID and name
of the thread that hit a breakpoint or received a signal.
gdb/ChangeLog:
2016-01-18 Pedro Alves <palves@redhat.com>
* NEWS: Mention that GDB now displays the ID and name of the
thread that hit a breakpoint or received a signal.
* break-catch-sig.c (signal_catchpoint_print_it): Use
maybe_print_thread_hit_breakpoint.
* break-catch-syscall.c (print_it_catch_syscall): Likewise.
* break-catch-throw.c (print_it_exception_catchpoint): Likewise.
* breakpoint.c (maybe_print_thread_hit_breakpoint): New function.
(print_it_catch_fork, print_it_catch_vfork, print_it_catch_solib)
(print_it_catch_exec, print_it_ranged_breakpoint)
(print_it_watchpoint, print_it_masked_watchpoint, bkpt_print_it):
Use maybe_print_thread_hit_breakpoint.
* breakpoint.h (maybe_print_thread_hit_breakpoint): Declare.
* gdbthread.h (show_thread_that_caused_stop): Declare.
* infrun.c (print_signal_received_reason): Print which thread
received signal.
* thread.c (show_thread_that_caused_stop): New function.
gdb/testsuite/ChangeLog:
2016-01-18 Pedro Alves <palves@redhat.com>
* gdb.base/async-shell.exp: Adjust expected output.
* gdb.base/dprintf-non-stop.exp: Adjust expected output.
* gdb.base/siginfo-thread.exp: Adjust expected output.
* gdb.base/watchpoint-hw-hit-once.exp: Adjust expected output.
* gdb.java/jnpe.exp: Adjust expected output.
* gdb.threads/clone-new-thread-event.exp: Adjust expected output.
* gdb.threads/continue-pending-status.exp: Adjust expected output.
* gdb.threads/leader-exit.exp: Adjust expected output.
* gdb.threads/manythreads.exp: Adjust expected output.
* gdb.threads/pthreads.exp: Adjust expected output.
* gdb.threads/schedlock.exp: Adjust expected output.
* gdb.threads/siginfo-threads.exp: Adjust expected output.
* gdb.threads/signal-command-multiple-signals-pending.exp: Adjust
expected output.
* gdb.threads/signal-delivered-right-thread.exp: Adjust expected
output.
* gdb.threads/sigthread.exp: Adjust expected output.
* gdb.threads/watchpoint-fork.exp: Adjust expected output.
This commit changes GDB to track thread numbers per-inferior. Then,
if you're debugging multiple inferiors, GDB displays
"inferior-num.thread-num" instead of just "thread-num" whenever it
needs to display a thread:
(gdb) info inferiors
Num Description Executable
1 process 6022 /home/pedro/gdb/tests/threads
* 2 process 6037 /home/pedro/gdb/tests/threads
(gdb) info threads
Id Target Id Frame
1.1 Thread 0x7ffff7fc2740 (LWP 6022) "threads" (running)
1.2 Thread 0x7ffff77c0700 (LWP 6028) "threads" (running)
1.3 Thread 0x7ffff7fc2740 (LWP 6032) "threads" (running)
2.1 Thread 0x7ffff7fc1700 (LWP 6037) "threads" (running)
2.2 Thread 0x7ffff77c0700 (LWP 6038) "threads" (running)
* 2.3 Thread 0x7ffff7fc2740 (LWP 6039) "threads" (running)
(gdb)
...
(gdb) thread 1.1
[Switching to thread 1.1 (Thread 0x7ffff7fc2740 (LWP 8155))]
(gdb)
...
etc.
You can still use "thread NUM", in which case GDB infers you're
referring to thread NUM of the current inferior.
The $_thread convenience var and Python's InferiorThread.num attribute
are remapped to the new per-inferior thread number. It's a backward
compatibility break, but since it only matters when debugging multiple
inferiors, I think it's worth doing.
Because MI thread IDs need to be a single integer, we keep giving
threads a global identifier, _in addition_ to the per-inferior number,
and make MI always refer to the global thread IDs. IOW, nothing
changes from a MI frontend's perspective.
Similarly, since Python's Breakpoint.thread and Guile's
breakpoint-thread/set-breakpoint-thread breakpoint methods need to
work with integers, those are adjusted to work with global thread IDs
too. Follow up patches will provide convenient means to access
threads' global IDs.
To avoid potencially confusing users (which also avoids updating much
of the testsuite), if there's only one inferior and its ID is "1",
IOW, the user hasn't done anything multi-process/inferior related,
then the "INF." part of thread IDs is not shown. E.g,.:
(gdb) info inferiors
Num Description Executable
* 1 process 15275 /home/pedro/gdb/tests/threads
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fc1740 (LWP 15275) "threads" main () at threads.c:40
(gdb) add-inferior
Added inferior 2
(gdb) info threads
Id Target Id Frame
* 1.1 Thread 0x7ffff7fc1740 (LWP 15275) "threads" main () at threads.c:40
(gdb)
No regressions on x86_64 Fedora 20.
gdb/ChangeLog:
2016-01-13 Pedro Alves <palves@redhat.com>
* NEWS: Mention that thread IDs are now per inferior and global
thread IDs.
* Makefile.in (SFILES): Add tid-parse.c.
(COMMON_OBS): Add tid-parse.o.
(HFILES_NO_SRCDIR): Add tid-parse.h.
* ada-tasks.c: Adjust to use ptid_to_global_thread_id.
* breakpoint.c (insert_breakpoint_locations)
(remove_threaded_breakpoints, bpstat_check_breakpoint_conditions)
(print_one_breakpoint_location, set_longjmp_breakpoint)
(check_longjmp_breakpoint_for_call_dummy)
(set_momentary_breakpoint): Adjust to use global IDs.
(find_condition_and_thread, watch_command_1): Use parse_thread_id.
(until_break_command, longjmp_bkpt_dtor)
(breakpoint_re_set_thread, insert_single_step_breakpoint): Adjust
to use global IDs.
* dummy-frame.c (pop_dummy_frame_bpt): Adjust to use
ptid_to_global_thread_id.
* elfread.c (elf_gnu_ifunc_resolver_stop): Likewise.
* gdbthread.h (struct thread_info): Rename field 'num' to
'global_num. Add new fields 'per_inf_num' and 'inf'.
(thread_id_to_pid): Rename thread_id_to_pid to
global_thread_id_to_ptid.
(pid_to_thread_id): Rename to ...
(ptid_to_global_thread_id): ... this.
(valid_thread_id): Rename to ...
(valid_global_thread_id): ... this.
(find_thread_id): Rename to ...
(find_thread_global_id): ... this.
(ALL_THREADS, ALL_THREADS_BY_INFERIOR): Declare.
(print_thread_info): Add comment.
* tid-parse.h: New file.
* tid-parse.c: New file.
* infcmd.c (step_command_fsm_prepare)
(step_command_fsm_should_stop): Adjust to use the global thread
ID.
(until_next_command, until_next_command)
(finish_command_fsm_should_stop): Adjust to use the global thread
ID.
(attach_post_wait): Adjust to check the inferior number too.
* inferior.h (struct inferior) <highest_thread_num>: New field.
* infrun.c (handle_signal_stop)
(insert_exception_resume_breakpoint)
(insert_exception_resume_from_probe): Adjust to use the global
thread ID.
* record-btrace.c (record_btrace_open): Use global thread IDs.
* remote.c (process_initial_stop_replies): Also consider the
inferior number.
* target.c (target_pre_inferior): Clear the inferior's highest
thread num.
* thread.c (clear_thread_inferior_resources): Adjust to use the
global thread ID.
(new_thread): New inferior parameter. Adjust to use it. Set both
the thread's global ID and the thread's per-inferior ID.
(add_thread_silent): Adjust.
(find_thread_global_id): New.
(find_thread_id): Make static. Adjust to rename.
(valid_thread_id): Rename to ...
(valid_global_thread_id): ... this.
(pid_to_thread_id): Rename to ...
(ptid_to_global_thread_id): ... this.
(thread_id_to_pid): Rename to ...
(global_thread_id_to_ptid): ... this. Adjust.
(first_thread_of_process): Adjust.
(do_captured_list_thread_ids): Adjust to use global thread IDs.
(should_print_thread): New function.
(print_thread_info): Rename to ...
(print_thread_info_1): ... this, and add new show_global_ids
parameter. Handle it. Iterate over inferiors.
(print_thread_info): Reimplement as wrapper around
print_thread_info_1.
(show_inferior_qualified_tids): New function.
(print_thread_id): Use it.
(tp_array_compar): Compare inferior numbers too.
(thread_apply_command): Use tid_range_parser.
(do_captured_thread_select): Use parse_thread_id.
(thread_id_make_value): Adjust.
(_initialize_thread): Adjust "info threads" help string.
* varobj.c (struct varobj_root): Update comment.
(varobj_create): Adjust to use global thread IDs.
(value_of_root_1): Adjust to use global_thread_id_to_ptid.
* windows-tdep.c (display_tib): No longer accept an argument.
* cli/cli-utils.c (get_number_trailer): Make extern.
* cli/cli-utils.h (get_number_trailer): Declare.
(get_number_const): Adjust documentation.
* mi/mi-cmd-var.c (mi_cmd_var_update_iter): Adjust to use global
thread IDs.
* mi/mi-interp.c (mi_new_thread, mi_thread_exit)
(mi_on_normal_stop, mi_output_running_pid, mi_on_resume):
* mi/mi-main.c (mi_execute_command, mi_cmd_execute): Likewise.
* guile/scm-breakpoint.c (gdbscm_set_breakpoint_thread_x):
Likewise.
* python/py-breakpoint.c (bppy_set_thread): Likewise.
* python/py-finishbreakpoint.c (bpfinishpy_init): Likewise.
* python/py-infthread.c (thpy_get_num): Add comment and return the
per-inferior thread ID.
(thread_object_getset): Update comment of "num".
gdb/testsuite/ChangeLog:
2016-01-07 Pedro Alves <palves@redhat.com>
* gdb.base/break.exp: Adjust to output changes.
* gdb.base/hbreak2.exp: Likewise.
* gdb.base/sepdebug.exp: Likewise.
* gdb.base/watch_thread_num.exp: Likewise.
* gdb.linespec/keywords.exp: Likewise.
* gdb.multi/info-threads.exp: Likewise.
* gdb.threads/thread-find.exp: Likewise.
* gdb.multi/tids.c: New file.
* gdb.multi/tids.exp: New file.
gdb/doc/ChangeLog:
2016-01-07 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Threads): Document per-inferior thread IDs,
qualified thread IDs, global thread IDs and thread ID lists.
(Set Watchpoints, Thread-Specific Breakpoints): Adjust to refer to
thread IDs.
(Convenience Vars): Document the $_thread convenience variable.
(Ada Tasks): Adjust to refer to thread IDs.
(GDB/MI Async Records, GDB/MI Thread Commands, GDB/MI Ada Tasking
Commands, GDB/MI Variable Objects): Update to mention global
thread IDs.
* guile.texi (Breakpoints In Guile)
<breakpoint-thread/set-breakpoint-thread breakpoint>: Mention
global thread IDs instead of thread IDs.
* python.texi (Threads In Python): Adjust documentation of
InferiorThread.num.
(Breakpoint.thread): Mention global thread IDs instead of thread
IDs.
Add a new function to print a thread ID, in the style of paddress,
plongest, etc. and adjust all CLI-reachable paths to use it.
This gives us a single place to tweak to print inferior-qualified
thread IDs later:
- [Switching to thread 1 (Thread 0x7ffff7fc2740 (LWP 8155))]
+ [Switching to thread 1.1 (Thread 0x7ffff7fc2740 (LWP 8155))]
etc., though for now, this has no user-visible change.
No regressions on x86_64 Fedora 20.
gdb/ChangeLog:
2016-01-13 Pedro Alves <palves@redhat.com>
* breakpoint.c (remove_threaded_breakpoints)
(print_one_breakpoint_location): Use print_thread_id.
* btrace.c (btrace_enable, btrace_disable, btrace_teardown)
(btrace_fetch, btrace_clear): Use print_thread_id.
* common/print-utils.c (CELLSIZE): Delete.
(get_cell): Rename to ...
(get_print_cell): ... this and made extern. Adjust call callers.
Adjust to use PRINT_CELL_SIZE.
* common/print-utils.h (get_print_cell): Declare.
(PRINT_CELL_SIZE): New.
* gdbthread.h (print_thread_id): Declare.
* infcmd.c (signal_command): Use print_thread_id.
* inferior.c (print_inferior): Use print_thread_id.
* infrun.c (handle_signal_stop)
(insert_exception_resume_breakpoint)
(insert_exception_resume_from_probe)
(print_signal_received_reason): Use print_thread_id.
* record-btrace.c (record_btrace_info)
(record_btrace_resume_thread, record_btrace_cancel_resume)
(record_btrace_step_thread, record_btrace_wait): Use
print_thread_id.
* thread.c (thread_apply_all_command): Use print_thread_id.
(print_thread_id): New function.
(thread_apply_command): Use print_thread_id.
(thread_command, thread_find_command, do_captured_thread_select):
Use print_thread_id.
Before, on systems that did not support PTRACE_EVENT_CLONE, both GDB and
GDBServer coordinated with libthread_db.so to insert breakpoints at magic
locations in libpthread.so, in order to break at thread creation and
thread death.
Support for thread events was removed from GDBServer as patch:
https://sourceware.org/ml/gdb-patches/2015-11/msg00466.html
This patch removes support for thread events in GDB.
No regressions found on Ubuntu 14.04 x86_64.
gdb/ChangeLog:
* breakpoint.c (remove_thread_event_breakpoints): Remove.
* breakpoint.h (remove_thread_event_breakpoints): Remove
declaration.
* linux-nat.c (in_pid_list_p): Remove.
(lin_lwp_attach_lwp): Remove.
* linux-nat.h (lin_lwp_attach_lwp): Remove declaration.
* linux-thread-db.c (thread_db_use_events): Remove.
(struct thread_db_info) <td_create_bp_addr>: Remove.
<td_death_bp_addr>: Likewise.
<td_ta_event_addr_p>: Likewise.
<td_ta_set_event_p>: Likewise.
<td_ta_clear_event_p>: Likewise.
<td_ta_event_getmsg_p>: Likewise.
<td_thr_event_enable_p>: Likewise.
(attach_thread): Likewise.
(detach_thread): Likewise.
(have_threads_callback): Likewise.
(have_threads): Likewise.
(enable_thread_event): Likewise.
(enable_thread_event_reporting): Likewise.
(try_thread_db_load_1): Remove td_ta_event_addr, td_ta_set_event,
td_ta_clear_event, td_ta_event_getmsg, td_thr_event_enable
initializations.
(try_thread_db_load_1): Remove enable_thread_event_reporting call.
(disable_thread_event_reporting): Remove.
(record_thread): Adapt to thread_db_use_event removal.
(detach_thread): Remove.
(thread_db_detach): Adapt to thread_db_use_event removal.
(check_event): Remove.
(thread_db_wait): Adapt to thread events support removal.
(thread_db_mourn_inferior): Likewise.
(find_new_threads_callback): Likewise.
(find_new_threads_once): Likewise.
(thread_db_update_thread_list): Likewise.
When trying to save fast tracepoints to file, gdb returns internal failure:
gdb/breakpoint.c:13446: internal-error: unhandled tracepoint type 27
A problem internal to GDB has been detected, further debugging may prove unreliable.
And no file including the fast tracepoints definition is created.
The patch also extends save-trace.exp to test saving tracepoint with a
fast tracepoint in there. Note that because this test doesn't actually
inserts the tracepoints in the program, we can run it with targets that
don't actually support fast tracepoints (or tracepoints at all).
gdb/ChangeLog:
* breakpoint.c (tracepoint_print_recreate): Fix logic error
if -> else if.
gdb/testsuite/ChangeLog:
* gdb.trace/actions.c: Include trace-common.h.
(main): Add a location for a fast tracepoint.
* gdb.trace/save-trace.exp: Set a fast tracepoint in addition to
the normal tracepoints.
(gdb_verify_tracepoints): Adjust number of expected tracepoints.
Fixes:
src/gdb/breakpoint.c: In function ‘void update_watchpoint(watchpoint*, int)’:
src/gdb/breakpoint.c:2147:31: error: invalid conversion from ‘int’ to ‘target_hw_bp_type’ [-fpermissive]
base->loc->watchpoint_type = -1;
^
Seems better to rely on "address == -1 && length == -1" than on a enum
value that's not really part of the set of supposedly valid enum
values. Also, factor that out to separate functions for better
localization of the concept.
gdb/ChangeLog:
2015-11-19 Pedro Alves <palves@redhat.com>
* breakpoint.c (software_watchpoint_add_no_memory_location)
(is_no_memory_software_watchpoint): New functions.
(update_watchpoint): Use
software_watchpoint_add_memoryless_location.
(breakpoint_address_bits): Use is_no_memory_software_watchpoint.
Assuming displaced stepping is enabled, and a breakpoint is set in the
memory region of the scratch pad, things break. One of two cases can
happen:
#1 - The breakpoint wasn't inserted yet (all threads were stopped), so
after setting up the displaced stepping scratch pad with the
adjusted copy of the instruction we're trying to single-step, we
insert the breakpoint, which corrupts the scratch pad, and the
inferior executes the wrong instruction. (Example below.)
This is clearly unacceptable.
#2 - The breakpoint was already inserted, so setting up the displaced
stepping scratch pad overwrites the breakpoint. This is OK in
the sense that we already assume that no thread is going to
executes the code in the scratch pad range (after initial
startup) anyway.
This commit addresses both cases by simply punting on displaced
stepping if we have a breakpoint in the scratch pad range.
The #1 case above explains a few regressions exposed by the AS/NS
series on x86:
Running ./gdb.dwarf2/callframecfa.exp ...
FAIL: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 1 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 2 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 3 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 4 for call-frame-cfa
Running ./gdb.dwarf2/typeddwarf.exp ...
FAIL: gdb.dwarf2/typeddwarf.exp: continue to breakpoint: continue to typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of x at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of y at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of z at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: continue to breakpoint: continue to typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of w at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of x at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of y at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of z at typeddwarf.c:73
Enabling "maint set target-non-stop on" implies displaced stepping
enabled as well, and it's the latter that's to blame here. We can see
the same failures with "maint set target-non-stop off + set displaced
on".
Diffing (good/bad) gdb.log for callframecfa.exp shows:
@@ -99,29 +99,29 @@ Breakpoint 2 at 0x80481b0: file q.c, lin
continue
Continuing.
-Breakpoint 2, func (arg=77) at q.c:2
+Breakpoint 2, func (arg=52301) at q.c:2
2 in q.c
(gdb) PASS: gdb.dwarf2/callframecfa.exp: continue to breakpoint: continue to breakpoint for call-frame-cfa
display arg
-1: arg = 77
-(gdb) PASS: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
+1: arg = 52301
+(gdb) FAIL: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
The problem is here, when setting up the func call:
Breakpoint 1, main (argc=-13345, argv=0x0) at q.c:7
7 in q.c
(gdb) disassemble
Dump of assembler code for function main:
0x080481bb <+0>: push %ebp
0x080481bc <+1>: mov %esp,%ebp
0x080481be <+3>: sub $0x4,%esp
=> 0x080481c1 <+6>: movl $0x4d,(%esp)
0x080481c8 <+13>: call 0x80481b0 <func>
0x080481cd <+18>: leave
0x080481ce <+19>: ret
End of assembler dump.
(gdb) disassemble /r
Dump of assembler code for function main:
0x080481bb <+0>: 55 push %ebp
0x080481bc <+1>: 89 e5 mov %esp,%ebp
0x080481be <+3>: 83 ec 04 sub $0x4,%esp
=> 0x080481c1 <+6>: c7 04 24 4d 00 00 00 movl $0x4d,(%esp)
0x080481c8 <+13>: e8 e3 ff ff ff call 0x80481b0 <func>
0x080481cd <+18>: c9 leave
0x080481ce <+19>: c3 ret
End of assembler dump.
Note the breakpoint at main is set at 0x080481c1. Right at the
instruction that sets up func's argument. Executing that instruction
should write 0x4d to the address pointed at by $esp. However, if we
stepi, the program manages to write 52301/0xcc4d there instead (0xcc
is int3, the x86 breakpoint instruction), because the breakpoint
address is 4 bytes inside the scratch pad location, which is
0x080481bd:
(gdb) p 0x080481c1 - 0x080481bd
$1 = 4
IOW, instead of executing:
"c7 04 24 4d 00 00 00" [ movl $0x4d,(%esp) ]
the inferior executes:
"c7 04 24 4d cc 00 00" [ movl $0xcc4d,(%esp) ]
gdb/ChangeLog:
2015-10-30 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoint_in_range_p)
(breakpoint_location_address_range_overlap): New functions.
* breakpoint.h (breakpoint_in_range_p): New declaration.
* infrun.c (displaced_step_prepare_throw): If there's a breakpoint
in the scratch pad range, don't displaced step.
Nowadays, GDB calls target_can_download_tracepoint at the entry of
download_tracepoint_locations, which is called by.
update_global_location_list. Sometimes, it is not needed to call
target_can_download_tracepoint at all because there is no tracepoint
created. In remote target, target_can_download_tracepoint send
qTStatus to the remote in order to know whether tracepoint can be
downloaded or not. This means some redundant qTStatus packets are
sent.
This patch is to teach GDB to call target_can_download_tracepoint
lazily, only on the moment there are tracepoint to download.
gdb.perf/single-step.exp (with a local patch to measure RSP packets)
shows the number of RSP packets is reduced because there is no
tracepoint at all, so GDB doesn't send qTStatus any more.
# of RSP packets
original patched
single-step rsp 1000 7000 6000
single-step rsp 2000 14000 12000
single-step rsp 3000 21000 18000
single-step rsp 4000 28000 24000
gdb:
2015-09-10 Yao Qi <yao.qi@linaro.org>
* breakpoint.c (download_tracepoint_locations): New local
can_download_tracepoint. Check the result of
target_can_download_tracepoint and save it in
can_download_tracepoint if there are tracepoints to download.
* linux-nat.h (enum tribool): Move it to ...
* common/common-types.h: ... here.
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* breakpoint.c: Include "thread-fsm.h".
(struct until_break_command_continuation_args): Delete.
(struct until_break_fsm): New.
(until_break_fsm_ops): New global.
(new_until_break_fsm, until_break_fsm_should_stop): New functions.
(until_break_command_continuation): Delete.
(until_break_fsm_clean_up): New function.
(until_break_fsm_async_reply_reason): New function.
(until_break_command): Adjust to create an until_break_fsm instead
of a continuation.
(momentary_bkpt_print_it): No longer print MI's async-stop-reason
here.
* infcmd.c (struct until_next_fsm): New.
(until_next_fsm_ops): New global.
(new_until_next_fsm, until_next_fsm_should_stop): New function.
(until_next_continuation): Delete.
(until_next_fsm_clean_up, until_next_fsm_async_reply_reason): New
functions.
(until_next_command): Adjust to create a new until_next_fsm
instead of a continuation.
This adds an object oriented replacement for the "struct continuation"
mechanism, and converts the stepping commands (step, next, stepi,
nexti) and the "finish" commands to use it.
It adds a new thread "class" (struct thread_fsm) that contains the
necessary info and callbacks to manage the state machine of a thread's
execution command.
This allows getting rid of some hacks. E.g., in fetch_inferior_event
and normal_stop we no longer need to know whether a thread is doing a
multi-step (e.g., step N). This effectively makes the
intermediate_continuations unused -- they'll be garbage collected in a
separate patch. (They were never a proper abstraction, IMO. See how
fetch_inferior_event needs to check step_multi before knowing whether
to call INF_EXEC_CONTINUE or INF_EXEC_COMPLETE.)
The target async vs !async uiout hacks in mi_on_normal_stop go away
too.
print_stop_event is no longer called from normal_stop. Instead it is
now called from within each interpreter's normal_stop observer. This
clears the path to make each interpreter print a stop event the way it
sees fit. Currently we have some hacks in common code to
differenciate CLI vs TUI vs MI around this area.
The "finish" command's FSM class stores the return value plus that
value's position in the value history, so that those can be printed to
both MI and CLI's streams. This fixes the CLI "finish" command when
run from MI -- it now also includes the function's return value in the
CLI stream:
(gdb)
~"callee3 (strarg=0x400730 \"A string argument.\") at src/gdb/testsuite/gdb.mi/basics.c:35\n"
~"35\t}\n"
+~"Value returned is $1 = 0\n"
*stopped,reason="function-finished",frame=...,gdb-result-var="$1",return-value="0",thread-id="1",stopped-threads="all",core="0"
-FAIL: gdb.mi/mi-cli.exp: CLI finish: check CLI output
+PASS: gdb.mi/mi-cli.exp: CLI finish: check CLI output
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* Makefile.in (COMMON_OBS): Add thread-fsm.o.
* breakpoint.c (handle_jit_event): Print debug output.
(bpstat_what): Split event callback handling to ...
(bpstat_run_callbacks): ... this new function.
(momentary_bkpt_print_it): No longer handle bp_finish here.
* breakpoint.h (bpstat_run_callbacks): Declare.
* gdbthread.h (struct thread_info) <step_multi>: Delete field.
<thread_fsm>: New field.
(thread_cancel_execution_command): Declare.
* infcmd.c: Include thread-fsm.h.
(struct step_command_fsm): New.
(step_command_fsm_ops): New global.
(new_step_command_fsm, step_command_fsm_prepare): New functions.
(step_1): Adjust to use step_command_fsm_prepare and
prepare_one_step.
(struct step_1_continuation_args): Delete.
(step_1_continuation): Delete.
(step_command_fsm_should_stop): New function.
(step_once): Delete.
(step_command_fsm_clean_up, step_command_fsm_async_reply_reason)
(prepare_one_step): New function, based on step_once.
(until_next_command): Remove step_multi reference.
(struct return_value_info): New.
(print_return_value): Rename to ...
(print_return_value_1): ... this. New struct return_value_info
parameter. Adjust.
(print_return_value): Reimplement as wrapper around
print_return_value_1.
(struct finish_command_fsm): New.
(finish_command_continuation): Delete.
(finish_command_fsm_ops): New global.
(new_finish_command_fsm, finish_command_fsm_should_stop): New
functions.
(finish_command_fsm_clean_up, finish_command_fsm_return_value):
New.
(finish_command_continuation_free_arg): Delete.
(finish_command_fsm_async_reply_reason): New.
(finish_backward, finish_forward): Change symbol parameter to a
finish_command_fsm. Adjust.
(finish_command): Create a finish_command_fsm. Adjust.
* infrun.c: Include "thread-fsm.h".
(clear_proceed_status_thread): Delete the thread's FSM.
(infrun_thread_stop_requested_callback): Cancel the thread's
execution command.
(clean_up_just_stopped_threads_fsms): New function.
(fetch_inferior_event): Handle the event_thread's should_stop
method saying the command isn't done yet.
(process_event_stop_test): Run breakpoint callbacks here.
(print_stop_event): Rename to ...
(print_stop_location): ... this.
(restore_current_uiout_cleanup): New function.
(print_stop_event): Reimplement.
(normal_stop): No longer notify the end_stepping_range observers
here handle "step N" nor "finish" here. No longer call
print_stop_event here.
* infrun.h (struct return_value_info): Forward declare.
(print_return_value): Declare.
(print_stop_event): Change prototype.
* thread-fsm.c: New file.
* thread-fsm.h: New file.
* thread.c: Include "thread-fsm.h".
(thread_cancel_execution_command): New function.
(clear_thread_inferior_resources): Call it.
* cli/cli-interp.c (cli_on_normal_stop): New function.
(cli_interpreter_init): Install cli_on_normal_stop as normal_stop
observer.
* mi/mi-interp.c: Include "thread-fsm.h".
(restore_current_uiout_cleanup): Delete.
(mi_on_normal_stop): If the thread has an FSM associated, and it
finished, ask it for the async-reply-reason to print. Always call
print_stop_event here, regardless of the top-level interpreter.
Check bpstat_what to tell whether an asynchronous breakpoint hit
triggered.
* tui/tui-interp.c (tui_on_normal_stop): New function.
(tui_init): Install tui_on_normal_stop as normal_stop observer.
gdb/testsuite/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* gdb.mi/mi-cli.exp: Add CLI finish tests.
This patch makes the execution control code use largely the same
mechanisms in both sync- and async-capable targets. This means using
continuations and use the event loop to react to target events on sync
targets as well. The trick is to immediately mark infrun's event loop
source after resume instead of calling wait_for_inferior. Then
fetch_inferior_event is adjusted to do a blocking wait on sync
targets.
Tested on x86_64 Fedora 20, native and gdbserver, with and without
"maint set target-async off".
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_do_actions_1, until_break_command): Don't
check whether the target can async.
* inf-loop.c (inferior_event_handler): Only call target_async if
the target can async.
* infcall.c: Include top.h and interps.h.
(run_inferior_call): For the interpreter to sync mode while
running the infcall. Call wait_sync_command_done instead of
wait_for_inferior plus normal_stop.
* infcmd.c (prepare_execution_command): Don't check whether the
target can async when running in the foreground.
(step_1): Delete synchronous case handling.
(step_once): Always install a continuation, even in sync mode.
(until_next_command, finish_forward): Don't check whether the
target can async.
(attach_command_post_wait, notice_new_inferior): Always install a
continuation, even in sync mode.
* infrun.c (mark_infrun_async_event_handler): New function.
(proceed): In sync mode, mark infrun's event source instead of
waiting for events here.
(fetch_inferior_event): If the target can't async, do a blocking
wait.
(prepare_to_wait): In sync mode, mark infrun's event source.
(infrun_async_inferior_event_handler): No longer bail out if the
target can't async.
* infrun.h (mark_infrun_async_event_handler): New declaration.
* linux-nat.c (linux_nat_wait_1): Remove calls to
set_sigint_trap/clear_sigint_trap.
(linux_nat_terminal_inferior): No longer check whether the target
can async.
* mi/mi-interp.c (mi_on_sync_execution_done): Update and simplify
comment.
(mi_execute_command_input_handler): No longer check whether the
target is async. Update and simplify comment.
* target.c (default_target_wait): New function.
* target.h (struct target_ops) <to_wait>: Now defaults to
default_target_wait.
(default_target_wait): Declare.
* top.c (wait_sync_command_done): New function, factored out from
...
(maybe_wait_sync_command_done): ... this.
* top.h (wait_sync_command_done): Declare.
* target-delegates.c: Regenerate.
BuildBot reminded me that "explicit" is a reserved keyword in C++.
This patch simply renames all the (illegal) uses of "explicit". This should
fix the build errors with --enable-build-with-cxx bots.
gdb/ChangeLog
* break-catch-throw.c (re_set_exception_catchpoint) Rename
reserved C++ keyword "explicit" to "explicit_loc".
* breakpoint.c (create_overlay_event_breakpoint)
(create_longjmp_master_breakpoint)
(create_std_terminate_master_breakpoint)
(create_exception_master_breakpoint, update_static_tracepoint):
Rename reserved C++ keyword "explicit" to "explicit_loc".
* completer.c (collect_explicit_location_matches)
(explicit_location_completer): Rename reserved C++ keyword
"explicit" to "explicit_loc".
* linespec.c (struct linespec) <explicit>: Rename to "explicit_loc".
(canonicalize_linespec, create_sals_line_offset)
(convert_linespec_to_sals, convert_explicit_location_to_sals)
(event_location_to_sals, decode_objc): Rename reserved C++ keyword
"explicit" to "explicit_loc".
* location.c (struct event_location) <explicit>: Rename to
"explicit_loc".
(initialize_explicit_location, new_explicit_location)
(explicit_location_to_string_internal, explicit_location_to_linespec):
Rename reserved C++ keyword "explicit" to "explicit_loc".
* location.h (explicit_location_to_string)
(explicit_location_to_linespec, initialize_explicit_location)
(new_explicit_location): Rename reserved C++ keyword "explicit"
to "explicit_loc".
* mi/mi-cmd-break.c (mi_cmd_break_insert_1): Rename reserved C++
keyword "explicit" to "explicit_loc".
While running bare-metal tests with GDB i noticed some failures in
gdb.base/break.exp, related to the use of the catch commands.
It turns out GDB tries to access memory address 0x0 whenever one tries
to insert a catchpoint, which should obviously not happen.
This was introduced with the changes for permanent breakpoints. In special,
bp_loc_is_permanent tries to check if there is a breakpoint inserted at
the same address as the current breakpoint's location's address. In the
case of catchpoints, this is 0x0.
(top-gdb) catch fork
Sending packet: $m0,1#fa...Packet received: E01
Catchpoint 4 (fork)
(top-gdb) catch vfork
Sending packet: $m0,1#fa...Packet received: E01
Catchpoint 5 (vfork)
It is not obvious to detect because this fails silently for Linux. For our
bare-metal testing, though, this fails with a clear error message from the
target about not being able to read such address.
The attached patch addresses this by bailing out of bp_loc_is_permanent (...)
if the location address is not meaningful. I also took the opportunity to
update the comment for breakpoint_address_is_meaningful, which mentioned
breakpoint addresses as opposed to their locations' addresses.
gdb/ChangeLog:
2015-08-11 Luis Machado <lgustavo@codesourcery.com>
* breakpoint.c (bp_loc_is_permanent): Return 0 when breakpoint
location address is not meaningful.
(breakpoint_address_is_meaningful): Update comment.
This patch adds documentation for explicit locations to both the
User Manual and gdb's online help system.
gdb/ChangeLog:
* NEWS: Mention explicit locations.
* breakpoint.c [LOCATION_HELP_STRING]: New macro.
[BREAK_ARGS_HELP]: Use LOCATION_HELP_STRING.
(_initialize_breakpoint): Update documentation for
"clear", "break", "trace", "strace", "ftrace", and "dprintf".
gdb/doc/ChangeLog:
* gdb.texinfo (Thread-Specific Breakpoints, Printing Source Lines):
Use "location(s)"instead of "linespec(s)".
(Specifying a Location): Rewrite.
Add subsections describing linespec, address, and explicit locations.
Add node/menu for each subsection.
(Source and Machine Code, C Preprocessor Macros)
(Create and Delete Trace points)
(Extensions for Ada Tasks): Use "location(s)" instead of "linespec(s)".
(Continuing at a Different Address): Remove "linespec" examples.
Add reference to "Specify a Location"
(The -break-insert Command): Rewrite. Add anchor.
Add reference to appropriate manual section discussing locations.
(The -dprintf-insert Command): Refer to -break-insert for
specification of 'location'.
gdb/testsuite/ChangeLog:
* gdb.base/help.exp: Update help_breakpoint_text.
This patch add support for explicit locations and switches many linespec
locations to this new location type. This patch also converts all
linespec locations entered by the user to an explicit representation
internally (thus bypassing the linespec parser when resetting the
breakpoint).
This patch does not introduce any user-visible changes.
gdb/ChangeLog:
* break-catch-throw.c (re_set_exception_catchpoint): Convert
linespec into explicit location.
* breakpoint.c (create_overlay_breakpoint)
(create_longjmp_master_breakpoint)
(create_std_terminate_master_breakpoint)
(create_exception_master_breakpoint): Convert linespec into explicit
location.
(update_static_tracepoint): Convert linespec into explicit location.
* linespec.c (enum offset_relative_sign, struct line_offset): Move
location.h.
(struct linespec) <expression, expr_pc, source_filename>
<function_name, label_name, line_offset>: Replace with ...
<explicit>: ... this.
<is_linespec>: New member.
(PARSER_EXPLICIT): New accessor macro.
(undefined_label_error): New function.
(source_file_not_found_error): New function.
(linespec_parse_basic): The parser result is now an explicit location.
Use PARSER_EXPLICIT to access it.
Use undefined_label_error.
(canonicalize_linespec): Convert canonical linespec into explicit
location.
Move string representation of location to explicit_location_to_linespec
and use it and explicit_location_to_string to save string
representations of the canonical location.
(create_sals_line_offset, convert_linespec_to_sals): `ls' contains an
explicit location. Update all references.
(convert_explicit_location_to_sals): New function.
(parse_linespec): Use PARSER_EXPLICIT to access the parser
result's explicit location.
(linespec_state_constructor): Initialize is_linespec.
Use PARSER_EXPLICIT.
(linespec_parser_delete): Use PARSER_EXPLICIT to access the parser's
result.
(event_location_to_sals): For linespec locations, set is_linespec.
Handle explicit locations.
(decode_objc): 'ls' contains an explicit location now. Update all
references.
(symtabs_from_filename): Use source_file_not_found_error.
* location.c (struct event_location.u) <explicit>: New member.
(initialize_explicit_location): New function.
(initialize_event_location): Initialize explicit locations.
(new_explicit_location, get_explicit_location)
(get_explicit_location_const): New functions.
(explicit_to_string_internal): New function; most of contents moved
from canonicalize_linespec.
(explicit_location_to_string): New function.
(explicit_location_to_linespec): New function.
(copy_event_location, delete_event_location)
(event_location_to_string_const, event_location_empty_p): Handle
explicit locations.
* location.h (enum offset_relative_sign, struct line_offset): Move
here from linespec.h.
(enum event_location_type): Add EXPLICIT_LOCATION.
(struct explicit_location): New structure.
(explicit_location_to_string): Declare.
(explicit_location_to_linespec): Declare.
(new_explicit_location, get_explicit_locationp
(get_explicit_location_const, initialize_explicit_location): Declare.
This patch adds support for address locations, of the form "*ADDR".
[Support for address linespecs has been removed/replaced by this "new"
location type.] This patch also converts any existing address locations
from its previous linespec type.
gdb/ChangeLog:
* breakpoint.c (create_thread_event_breakpoint, init_breakpoint_sal):
Convert linespec to address location.
* linespec.c (canonicalize_linespec): Do not handle address
locations here.
(convert_address_location_to_sals): New function; contents moved
from ...
(convert_linespc_to_sals): ... here.
(parse_linespec): Remove address locations from linespec grammar.
Remove handling of address locations.
(linespec_lex_to_end): Remove handling of address linespecs.
(event_location_to_sals): Handle ADDRESS_LOCATION.
(linespec_expression_to_pc): Export.
* linespec.h (linespec_expression_to_pc): Add declaration.
* location.c (struct event_location.u) <address>: New member.
(new_address_location, get_address_location): New functions.
(copy_event_location, delete_event_location, event_location_to_string)
(string_to_event_location, event_location_empty_p): Handle address
locations.
* location.h (enum event_location_type): Add ADDRESS_LOCATION.
(new_address_location, get_address_location): Declare.
* python/py-finishbreakpoint.c (bpfinishpy_init): Convert linespec
to address location.
* spu-tdep.c (spu_catch_start): Likewise.
This patch converts the code base to use the new struct event_location
API being introduced. This patch preserves the current functionality and
adds no new features.
The "big picture" API usage introduced by this patch may be illustrated
with a simple exmaple. Where previously developers would write:
void
my_command (char *arg, int from_tty)
{
create_breakpoint (..., arg, ...);
...
}
one now uses:
void
my_command (char *arg, int from_tty)
{
struct event_locaiton *location;
struct cleanup *back_to;
location = string_to_event_locaiton (&arg, ...);
back_to = make_cleanup_delete_event_location (location);
create_breakpoint (..., location, ...);
do_cleanups (back_to);
}
Linespec-decoding functions (now called location-decoding) such as
decode_line_full no longer skip argument pointers over processed input.
That functionality has been moved into string_to_event_location as
demonstrated above.
gdb/ChangeLog
* ax-gdb.c: Include location.h.
(agent_command_1) Use linespec location instead of address
string.
* break-catch-throw.c: Include location.h.
(re_set_exception_catchpoint): Use linespec locations instead
of address strings.
* breakpoint.c: Include location.h.
(create_overlay_event_breakpoint, create_longjmp_master_breakpoint)
(create_std_terminate_master_breakpoint)
(create_exception_master_breakpoint, update_breakpoints_after_exec):
Use linespec location instead of address string.
(print_breakpoint_location): Use locations and
event_location_to_string.
Print extra_string for pending locations for non-MI streams.
(print_one_breakpoint_location): Use locations and
event_location_to_string.
(init_raw_breakpoint_without_location): Initialize b->location.
(create_thread_event_breakpoint): Use linespec location instead of
address string.
(init_breakpoint_sal): Likewise.
Only save extra_string if it is non-NULL and not the empty string.
Use event_location_to_string instead of `addr_string'.
Constify `p' and `endp'.
Use skip_spaces_const/skip_space_const instead of non-const versions.
Copy the location into the breakpoint.
If LOCATION is NULL, save the breakpoint address as a linespec location
instead of an address string.
(create_breakpoint_sal): Change `addr_string' parameter to a struct
event_location. All uses updated.
(create_breakpoints_sal): Likewise for local variable `addr_string'.
(parse_breakpoint_sals): Use locations instead of address strings.
Remove check for empty linespec with conditional.
Refactor.
(decode_static_tracepoint_spec): Make argument const and update
function.
(create_breakpoint): Change `arg' to a struct event_location and
rename.
Remove `copy_arg' and `addr_start'.
If EXTRA_STRING is empty, set it to NULL.
Don't populate `canonical' for pending breakpoints.
Pass `extra_string' to find_condition_and_thread.
Clear `extra_string' if `rest' was NULL.
Do not error with "garbage after location" if setting a dprintf
breakpoint.
Copy the location into the breakpoint instead of an address string.
(break_command_1): Use string_to_event_location and pass this to
create_breakpoint instead of an address string.
Check against `arg_cp' for a probe linespec.
(dprintf_command): Use string_to_event_location and pass this to
create_breakpoint instead of an address string.
Throw an exception if no format string was specified.
(print_recreate_ranged_breakpoint): Use event_location_to_string
instead of address strings.
(break_range_command, until_break_command)
(init_ada_exception_breakpoint): Use locations instead
of address strings.
(say_where): Print out extra_string for pending locations.
(base_breakpoint_dtor): Delete `location' and `location_range_end' of
the breakpoint.
(base_breakpoint_create_sals_from_location): Use struct event_location
instead of address string.
Remove `addr_start' and `copy_arg' parameters.
(base_breakpoint_decode_location): Use struct event_location instead of
address string.
(bkpt_re_set): Use locations instead of address strings.
Use event_location_empty_p to check for unset location.
(bkpt_print_recreate): Use event_location_to_string instead of
an address string.
Print out extra_string for pending locations.
(bkpt_create_sals_from_location, bkpt_decode_location)
(bkpt_probe_create_sals_from_location): Use struct event_location
instead of address string.
(bkpt_probe_decode_location): Use struct event_location instead of
address string.
(tracepoint_print_recreate): Use event_location_to_string to
recreate the tracepoint.
(tracepoint_create_sals_from_location, tracepoint_decode_location)
(tracepoint_probe_create_sals_from_location)
(tracepoint_probe_decode_location): Use struct event_location
instead of address string.
(dprintf_print_recreate): Use event_location_to_string to recreate
the dprintf.
(dprintf_re_set): Remove check for valid/missing format string.
(strace_marker_create_sals_from_location)
(strace_marker_create_breakpoints_sal, strace_marker_decode_location)
(update_static_tracepoint): Use struct event_location instead of
address string.
(location_to_sals): Likewise.
Pass `extra_string' to find_condition_and_thread.
For newly resolved pending breakpoint locations, clear the location's
string representation.
Assert that the breakpoint's condition string is NULL when
condition_not_parsed.
(breakpoint_re_set_default, create_sals_from_location_default)
(decode_location_default, trace_command, ftrace_command)
(strace_command, create_tracepoint_from_upload): Use locations
instead of address strings.
* breakpoint.h (struct breakpoint_ops) <create_sals_from_location>:
Use struct event_location instead of address string.
Update all uses.
<decode_location>: Likewise.
(struct breakpoint) <addr_string>: Change to struct event_location
and rename `location'.
<addr_string_range_end>: Change to struct event_location and rename
`location_range_end'.
(create_breakpoint): Use struct event_location instead of address
string.
* cli/cli-cmds.c: Include location.h.
(edit_command, list_command): Use locations instead of address strings.
* elfread.c: Include location.h.
(elf_gnu_ifunc_resolver_return_stop): Use event_location_to_string.
* guile/scm-breakpoint.c: Include location.h.
(bpscm_print_breakpoint_smob): Use event_location_to_string.
(gdbscm_register_breakpoint): Use locations instead of address
strings.
* linespec.c: Include location.h.
(struct ls_parser) <stream>: Change to const char *.
(PARSER_STREAM): Update.
(lionespec_lexer_lex_keyword): According to find_condition_and_thread,
keywords must be followed by whitespace.
(canonicalize_linespec): Save a linespec location into `canonical'.
Save a canonical linespec into `canonical'.
(parse_linespec): Change `argptr' to const char * and rename `arg'.
All uses updated.
Update function description.
(linespec_parser_new): Initialize `parser'.
Update initialization of parsing stream.
(event_location_to_sals): New function.
(decode_line_full): Change `argptr' to a struct event_location and
rename it `location'.
Use locations instead of address strings.
Call event_location_to_sals instead of parse_linespec.
(decode_line_1): Likewise.
(decode_line_with_current_source, decode_line_with_last_displayed)
Use locations instead of address strings.
(decode_objc): Likewise.
Change `argptr' to const char * and rename `arg'.
(destroy_linespec_result): Delete the linespec result's location
instead of freeing the address string.
* linespec.h (struct linespec_result) <addr_string>: Change to
struct event_location and rename to ...
<location>: ... this.
(decode_line_1, decode_line_full): Change `argptr' to struct
event_location. All callers updated.
* mi/mi-cmd-break.c: Include language.h, location.h, and linespec.h.
(mi_cmd_break_insert_1): Use locations instead of address strings.
Throw an error if there was "garbage" at the end of the specified
linespec.
* probe.c: Include location.h.
(parse_probes): Change `argptr' to struct event_location.
Use event locations instead of address strings.
* probe.h (parse_probes): Change `argptr' to struct event_location.
* python/py-breakpoint.c: Include location.h.
(bppy_get_location): Constify local variable `str'.
Use event_location_to_string.
(bppy_init): Use locations instead of address strings.
* python/py-finishbreakpoint.c: Include location.h.
(bpfinishpy_init): Remove local variable `addr_str'.
Use locations instead of address strings.
* python/python.c: Include location.h.
(gdbpy_decode_line): Use locations instead of address strings.
* remote.c: Include location.h.
(remote_download_tracepoint): Use locations instead of address
strings.
* spu-tdep.c: Include location.h.
(spu_catch_start): Remove local variable `buf'.
Use locations instead of address strings.
* tracepoint.c: Include location.h.
(scope_info): Use locations instead of address strings.
(encode_source_string): Constify parameter `src'.
* tracepoint.h (encode_source_string): Likewise.
gdb/testsuite/ChangeLog
* gdb.base/dprintf-pending.exp: Update dprintf "without format"
test.
Add tests for missing ",FMT" and ",".
This patch renames all occurrances of "addr_string" and "address
string" in the breakpoint/linespec APIs. This will emphasize the
change from address strings used in setting breakpoints (et al) to the
new locations-based API introduced in subsequent patches.
gdb/ChangeLog:
* breakpoint.h (struct breakpoint_ops) <create_sals_from_address>:
Renamed to create_sals_from_location.
<decode_linespec>: Renamed to decode_location.
Update all callers.
* breakpoint.c (create_sals_from_address_default): Renamed to ...
(create_sals_from_location_default): ... this.
(addr_string_to_sals): Renamed to ...
(location_to_sals): ... this.
(decode_linespec_default): Renamed to ...
(decode_location_default): ... this.
(base_breakpoint_create_sals_from_address): Renamed to ...
(base_breakpoint_create_sals_from_location): ... this.
(bkpt_create_sals_from_address): Renamed to ...
(bkpt_create_sals_from_location): ... this.
(bkpt_decode_linespec): Renamed to ...
(bkpt_decode_location): ... this.
(bkpt_probe_create_sals_from_address): Renamed to ...
(bkpt_probe_create_sals_from_location): ... this.
(tracepoint_create_sals_from_address): Renamed to ...
(tracepoint_create_sals_from_location): ... this.
(tracepoint_decode_linespec): Renamed to ...
(tracepoint_decode_location): ... this.
(tracepoint_probe_create_sals_from_address): Renamed to ...
(tracepoint_probe_create_sals_from_location): ... this.
(tracepoint_probe_decode_linespec): Renamed to ...
(tracepoint_probe_decode_location): ... this.
(strace_marker_create_sals_from_address): Renamed to ...
(strace_marker_create_sals_from_location): ... this.
(decode_linespec_default): Renamed to ...
(decode_location_default): ... this.
This finally implements user-visible all-stop mode running with the
target_ops backend always in non-stop mode. This is a stepping stone
towards finer-grained control of threads, being able to do interesting
things like thread groups, associating groups with breakpoints, etc.
From the user's perspective, all-stop mode is really just a special
case of being able to stop and resume specific sets of threads, so it
makes sense to do this step first.
With this, even in all-stop, the target is no longer in charge of
stopping all threads before reporting an event to the core -- the core
takes care of it when it sees fit. For example, when "next"- or
"step"-ing, we can avoid stopping and resuming all threads at each
internal single-step, and instead only stop all threads when we're
about to present the stop to the user.
The implementation is almost straight forward, as the heavy lifting
has been done already in previous patches. Basically, we replace
checks for "set non-stop on/off" (the non_stop global), with calls to
a new target_is_non_stop_p function. In a few places, if "set
non-stop off", we stop all threads explicitly, and in a few other
places we resume all threads explicitly, making use of existing
methods that were added for teaching non-stop to step over breakpoints
without displaced stepping.
This adds a new "maint set target-non-stop on/off/auto" knob that
allows both disabling the feature if we find problems, and
force-enable it for development (useful when teaching a target about
this. The default is "auto", which means the feature is enabled if a
new target method says it should be enabled. The patch implements the
method in linux-nat.c, just for illustration, because it still returns
false. We'll need a few follow up fixes before turning it on by
default. This is a separate target method from indicating regular
non-stop support, because e.g., while e.g., native linux-nat.c is
close to regression free with all-stop-non-stop (with following
patches will fixing the remaining regressions), remote.c+gdbserver
will still need more fixing, even though it supports "set non-stop
on".
Tested on x86_64 Fedora 20, native, with and without "set displaced
off", and with and without "maint set target-non-stop on"; and also
against gdbserver.
gdb/ChangeLog:
2015-08-07 Pedro Alves <palves@redhat.com>
* NEWS: Mention "maint set/show target-non-stop".
* breakpoint.c (update_global_location_list): Check
target_is_non_stop_p instead of non_stop.
* infcmd.c (attach_command_post_wait, attach_command): Likewise.
* infrun.c (show_can_use_displaced_stepping)
(can_use_displaced_stepping_p, start_step_over_inferior):
Likewise.
(internal_resume_ptid): New function.
(resume): Use it.
(proceed): Check target_is_non_stop_p instead of non_stop. If in
all-stop mode but the target is always in non-stop mode, start all
the other threads that are implicitly resumed too.
(for_each_just_stopped_thread, fetch_inferior_event)
(adjust_pc_after_break, stop_all_threads): Check
target_is_non_stop_p instead of non_stop.
(handle_inferior_event): Likewise. Handle detach-fork in all-stop
with the target always in non-stop mode.
(handle_signal_stop) <random signal>: Check target_is_non_stop_p
instead of non_stop.
(switch_back_to_stepped_thread): Check target_is_non_stop_p
instead of non_stop.
(keep_going_stepped_thread): Use internal_resume_ptid.
(stop_waiting): If in all-stop mode, and the target is in non-stop
mode, stop all threads.
(keep_going_pass): Likewise, when starting a new in-line step-over
sequence.
* linux-nat.c (get_pending_status, select_event_lwp)
(linux_nat_filter_event, linux_nat_wait_1, linux_nat_wait): Check
target_is_non_stop_p instead of non_stop.
(linux_nat_always_non_stop_p): New function.
(linux_nat_stop): Check target_is_non_stop_p instead of non_stop.
(linux_nat_add_target): Install linux_nat_always_non_stop_p.
* target-delegates.c: Regenerate.
* target.c (target_is_non_stop_p): New function.
(target_non_stop_enabled, target_non_stop_enabled_1): New globals.
(maint_set_target_non_stop_command)
(maint_show_target_non_stop_command): New functions.
(_initilize_target): Install "maint set/show target-non-stop"
commands.
* target.h (struct target_ops) <to_always_non_stop_p>: New field.
(target_non_stop_enabled): New declaration.
(target_is_non_stop_p): New declaration.
gdb/doc/ChangeLog:
2015-08-07 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Maintenance Commands): Document "maint set/show
target-non-stop".
That is, step past breakpoints by:
- pausing all threads
- removing breakpoint at PC
- single-step
- reinsert breakpoint
- restart threads
similarly to all-stop (with displaced stepping disabled). This allows
non-stop to work on targets/architectures without displaced stepping
support. That is, it makes displaced stepping an optimization instead
of a requirement. For example, in principle, all GNU/Linux ports
support non-stop mode at the target_ops level, but not all
corresponding gdbarch's implement displaced stepping. This should
make non-stop work for all (albeit, not as efficiently). And then
there are scenarios where even if the architecture supports displaced
stepping, we can't use it, because we e.g., don't find a usable
address to use as displaced step scratch pad. It should also fix
stepping past watchpoints on targets that have non-continuable
watchpoints in non-stop mode (e.g., PPC, untested). Running the
instruction out of line in the displaced stepping scratch pad doesn't
help that case, as the copied instruction reads/writes the same
watched memory... We can fix that too by teaching GDB to only remove
the watchpoint from the thread that we want to move past the
watchpoint (currently, removing a watchpoint always removes it from
all threads), but again, that can be considered an optimization; not
all targets would support it.
For those familiar with the gdb and gdbserver Linux target_ops
backends, the implementation should look similar, except it is done on
the core side. When we pause threads, we may find they stop with an
interesting event that should be handled later when the thread is
re-resumed, thus we store such events in the thread object, and mark
the event as pending. We should only consume pending events if the
thread is indeed resumed, thus we add a new "resumed" flag to the
thread object. At a later stage, we might add new target methods to
accelerate some of this, like "pause all threads", with corresponding
RSP packets, but we'd still need a fallback method for remote targets
that don't support such packets, so, again, that can be deferred as
optimization.
My _real_ motivation here is making it possible to reimplement
all-stop mode on top of the target always working on non-stop mode, so
that e.g., we can send RSP packets to a remote target even while the
target is running -- can't do that in the all-stop RSP variant, by
design).
Tested on x86_64 Fedora 20, with and without "set displaced off"
forced. The latter forces the new code paths whenever GDB needs to
step past a breakpoint.
gdb/ChangeLog:
2015-08-07 Pedro Alves <pedro@codesourcery.com>
* breakpoint.c (breakpoints_should_be_inserted_now): If any thread
has a pending status, return true.
* gdbthread.h: Include target/waitstatus.h.
(struct thread_suspend_state) <stop_reason, waitstatus_pending_p,
stop_pc>: New fields.
(struct thread_info) <resumed>: New field.
(set_resumed): Declare.
* infrun.c: Include "event-loop.h".
(infrun_async_inferior_event_token, infrun_is_async): New globals.
(infrun_async): New function.
(clear_step_over_info): Add debug output.
(displaced_step_in_progress_any_inferior): New function.
(displaced_step_fixup): New returns int.
(start_step_over): Handle in-line step-overs too. Assert the
thread is marked resumed.
(resume_cleanups): Clear the thread's resumed flag.
(resume): Set the thread's resumed flag. Return early if the
thread has a pending status. Allow stepping a breakpoint with no
signal.
(proceed): Adjust to check 'resumed' instead of 'executing'.
(clear_proceed_status_thread): If the thread has a pending status,
and that status is a finished step, discard the pending status.
(clear_proceed_status): Don't clear step_over_info here.
(random_pending_event_thread, do_target_wait): New functions.
(prepare_for_detach, wait_for_inferior, fetch_inferior_event): Use
do_target_wait.
(wait_one): New function.
(THREAD_STOPPED_BY): New macro.
(thread_stopped_by_watchpoint, thread_stopped_by_sw_breakpoint)
(thread_stopped_by_hw_breakpoint): New functions.
(switch_to_thread_cleanup, save_waitstatus, stop_all_threads): New
functions.
(handle_inferior_event): Also call set_resumed(false) on all
threads implicitly stopped by the event.
(restart_threads, resumed_thread_with_pending_status): New
functions.
(finish_step_over): If we were doing an in-line step-over before,
and no longer are after trying to start a new step-over, restart
all threads. If we have multiple threads with pending events,
save the current event and go through the event loop again.
(handle_signal_stop): Return early if finish_step_over returns
false.
<random signal>: If we get a signal while stepping over a
breakpoint in-line in non-stop mode, restart all threads. Clear
step_over_info before delivering the signal.
(keep_going_stepped_thread): Use internal_error instead of
gdb_assert. Mark the thread as resumed.
(keep_going_pass_signal): Assert the thread isn't already resumed.
If some other thread is doing an in-line step-over, defer the
resume. If we just started a new in-line step-over, stop all
threads. Don't clear step_over_info.
(infrun_async_inferior_event_handler): New function.
(_initialize_infrun): Create async event handler with
infrun_async_inferior_event_handler as callback.
(infrun_async): New declaration.
* target.c (target_async): New function.
* target.h (target_async): Declare macro and readd as function
declaration.
* target/waitstatus.h (enum target_stop_reason)
<TARGET_STOPPED_BY_SINGLE_STEP>: New value.
* thread.c (new_thread): Clear the new waitstatus field.
(set_resumed): New function.
At https://sourceware.org/ml/gdb-patches/2015-08/msg00097.html, Joel
observed that trying to next/step a program on GNU/Linux sometimes
results in the following failed assertion:
% gdb -q .obj/gprof/main
(gdb) start
(gdb) n
(gdb) step
[...]/infrun.c:2391: internal-error:
resume: Assertion `sig != GDB_SIGNAL_0' failed.
What happened is that, during the "next" operation, GDB hit a
longjmp/exception/step-resume breakpoint but failed to see that this
breakpoint was set for a different thread than the one being stepped.
Joel's detailed analysis follows:
More precisely, at the end of the "start" command, we are stopped at
the start of function Main in main.adb; there are 4 threads in total,
and we are in the main thread (which is thread 1):
(gdb) info thread
Id Target Id Frame
4 Thread 0xb7a56ba0 (LWP 28379) 0xffffe410 in __kernel_vsyscall ()
3 Thread 0xb7c5aba0 (LWP 28378) 0xffffe410 in __kernel_vsyscall ()
2 Thread 0xb7e5eba0 (LWP 28377) 0xffffe410 in __kernel_vsyscall ()
* 1 Thread 0xb7ea18c0 (LWP 28370) main () at /[...]/main.adb:57
All the logs below reference Thread ID/LWP, but it'll be easier to
talk about the threads by GDB thread number. For instance, thread 1
is LWP 28370 while thread 3 is LWP 28378. So, the explanations below
translate the LWPs into thread numbers.
Back to what happens while we are trying to "next' our program:
(gdb) n
infrun: clear_proceed_status_thread (Thread 0xb7a56ba0 (LWP 28379))
infrun: clear_proceed_status_thread (Thread 0xb7c5aba0 (LWP 28378))
infrun: clear_proceed_status_thread (Thread 0xb7e5eba0 (LWP 28377))
infrun: clear_proceed_status_thread (Thread 0xb7ea18c0 (LWP 28370))
infrun: proceed (addr=0xffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0xb7ea18c0 (LWP 28370)] at 0x805451e
infrun: target_wait (-1.0.0, status) =
infrun: 28370.28370.0 [Thread 0xb7ea18c0 (LWP 28370)],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x8054523
We've resumed thread 1 (LWP 28370), and received in return a signal
that the same thread stopped slightly further. It's still in the
range of instructions for the line of source we started the "next"
from, as evidenced by the following trace...
infrun: stepping inside range [0x805451e-0x8054531]
... and thus, we decide to continue stepping the same thread:
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0xb7ea18c0 (LWP 28370)] at 0x8054523
infrun: prepare_to_wait
That's when we get an event from a different thread (thread 3)...
infrun: target_wait (-1.0.0, status) =
infrun: 28370.28378.0 [Thread 0xb7c5aba0 (LWP 28378)],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x80782d0
infrun: context switch
infrun: Switching context from Thread 0xb7ea18c0 (LWP 28370) to Thread 0xb7c5aba0 (LWP 28378)
... which we find to be at the address where we set a breakpoint on
"the unwinder debug hook" (namely "_Unwind_DebugHook"). But GDB fails
to notice that the breakpoint was inserted for thread 1 only, and so
decides to handle it as...
infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME
... and inserts a breakpoint at the corresponding resume address, as
evidenced by this the next log:
infrun: exception resume at 80542a2
That breakpoint seems innocent right now, but will play a role fairly
quickly. But for now, GDB has inserted the exception-resume
breakpoint, and needs to single-step thread 3 past the breakpoint it
just hit. Thus, it temporarily disables the exception breakpoint, and
requests a step of that thread:
infrun: skipping breakpoint: stepping past insn at: 0x80782d0
infrun: skipping breakpoint: stepping past insn at: 0x80782d0
infrun: skipping breakpoint: stepping past insn at: 0x80782d0
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=1, current thread [Thread 0xb7c5aba0 (LWP 28378)] at 0x80782d0
infrun: prepare_to_wait
We then get a notification, still from thread 3, that it's now past
that breakpoint...
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 28370.28378.0 [Thread 0xb7c5aba0 (LWP 28378)],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x8078424
... so we can resume what we were doing before, which is single-stepping
thread 1 until we get to a new line of code:
infrun: switching back to stepped thread
infrun: Switching context from Thread 0xb7c5aba0 (LWP 28378) to Thread 0xb7ea18c0 (LWP 28370)
infrun: expected thread still hasn't advanced
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0xb7ea18c0 (LWP 28370)] at 0x8054523
The "resume" log above shows that we're resuming thread 1 from where
we left off (0x8054523). We get one more stop at 0x8054529, which is
still inside our stepping range so we go again. That's when we get
the following event, from thread 3:
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 28370.28378.0 [Thread 0xb7c5aba0 (LWP 28378)],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x80542a2
Now the stop_pc address is interesting, because it's the address of
"exception resume" breakpoint...
infrun: context switch
infrun: Switching context from Thread 0xb7ea18c0 (LWP 28370) to Thread 0xb7c5aba0 (LWP 28378)
infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
... and since that location is at a different line of code, this is
where it decides the "next" operation should stop:
infrun: stop_waiting
[Switching to Thread 0xb7c5aba0 (LWP 28378)]
0x080542a2 in inte_tache_rt.ttache_rt (
<_task>=0x80968ec <inte_tache_rt_inst.tache2>)
at /[...]/inte_tache_rt.adb:54
54 end loop;
However, what GDB should have noticed earlier that the exception
breakpoint we hit was for a different thread, thus should have
single-stepped that thread out of the breakpoint _without_ inserting
the exception-return breakpoint, and then resumed the single-stepping
of the initial thread (thread 1) until that thread stepped out of its
stepping range.
This is what this patch does, and after applying it, GDB now correctly
stops on the next line of code.
The patch adds a C++ test that exercises this, both for setjmp/longjmp
and exception breakpoints. With an unpatched GDB it shows:
(gdb) next
[Switching to Thread 22445.22455]
thread_try_catch (arg=0x0) at /home/pedro/gdb/mygit/build/../src/gdb/testsuite/gdb.threads/next-other-thr-longjmp.c:59
59 catch (...)
(gdb) FAIL: gdb.threads/next-other-thr-longjmp.exp: next to line 1
next
/home/pedro/gdb/mygit/build/../src/gdb/infrun.c:4865: internal-error: process_event_stop_test: Assertion `ecs->event_thread->control.exception_resume_breakpoint != NULL' fa
iled.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) FAIL: gdb.threads/next-other-thr-longjmp.exp: next to line 2 (GDB internal error)
Resyncing due to internal error.
n
Tested on x86_64-linux, no regressions.
gdb/ChangeLog:
2015-08-05 Pedro Alves <palves@redhat.com>
Joel Brobecker <brobecker@adacore.com>
* breakpoint.c (bpstat_what) <bp_longjmp, bp_longjmp_call_dummy>
<bp_exception, bp_longjmp_resume, bp_exception_resume>: Handle the
case where BS->STOP is not set.
gdb/testsuite/ChangeLog:
2015-08-05 Pedro Alves <palves@redhat.com>
* gdb.threads/next-while-other-thread-longjmps.c: New file.
* gdb.threads/next-while-other-thread-longjmps.exp: New file.
This patch removes the isize output argument from the
fast_tracepoint_valid_at gdbarch hook. It was used to return the size
of the instruction that needs to be replaced when installing a fast
tracepoint. Instead of getting this value from the
fast_tracepoint_valid_at hook, we can call the gdb_insn_length function.
If we do not do this, then architectures which do not have a restriction
on where to install the fast tracepoint will send uninitialized memory
off to GDBserver. See remote_download_tracepoint:
~~~
int isize;
if (gdbarch_fast_tracepoint_valid_at (target_gdbarch (),
tpaddr, &isize, NULL))
xsnprintf (buf + strlen (buf), BUF_SIZE - strlen (buf), ":F%x",
isize);
~~~
The default implementation of fast_tracepoint_valid_at will not set
isize resulting in uninitialized memory being sent. Later on, GDBserver
could use this information to compute a jump offset.
gdb/ChangeLog:
* arch-utils.c (default_fast_tracepoint_valid_at): Remove unused
isize argument.
* arch-utils.h (default_fast_tracepoint_valid_at): Likewise.
* breakpoint.c (check_fast_tracepoint_sals): Adjust call to
gdbarch_fast_tracepoint_valid_at.
* gdbarch.sh (fast_tracepoint_valid_at): Remove isize argument.
* gdbarch.h: Regenerate.
* gdbarch.c: Regenerate.
* i386-tdep.c (i386_fast_tracepoint_valid_at): Remove isize
argument. Do not set it.
* remote.c (remote_download_tracepoint): Adjust call to
gdbarch_fast_tracepoint_valid_at. Call gdb_insn_length to get
the instruction length.
This fixes regressions introduced with the original change to not
consider permanent breakpoints always inserted:
6ae8866180 is the first bad commit
commit 6ae8866180
Author: Luis Machado <lgustavo@codesourcery.com>
Date: Wed Jun 17 16:50:57 2015 -0300
Fix problems with finishing a dummy function call on simulators.
Some checks were mistakenly left out of the original patch, which
caused the following failures:
-PASS: gdb.base/shlib-call.exp: print mainshr1(1)
-PASS: gdb.base/shlib-call.exp: step into mainshr1
+FAIL: gdb.base/shlib-call.exp: print mainshr1(1)
+FAIL: gdb.base/shlib-call.exp: step into mainshr1
-PASS: gdb.cp/chained-calls.exp: q(p())
+FAIL: gdb.cp/chained-calls.exp: q(p())
-PASS: gdb.cp/chained-calls.exp: q(p() + r())
+FAIL: gdb.cp/chained-calls.exp: q(p() + r())
-PASS: gdb.cp/chained-calls.exp: g(f(g(f() + f())) + f())
+FAIL: gdb.cp/chained-calls.exp: g(f(g(f() + f())) + f())
-PASS: gdb.cp/chained-calls.exp: *c
-PASS: gdb.cp/chained-calls.exp: *c + *c
-PASS: gdb.cp/chained-calls.exp: q(*c + *c)
+FAIL: gdb.cp/chained-calls.exp: *c
+FAIL: gdb.cp/chained-calls.exp: *c + *c
+FAIL: gdb.cp/chained-calls.exp: q(*c + *c)
-PASS: gdb.cp/classes.exp: calling method for small class
+FAIL: gdb.cp/classes.exp: calling method for small class
The above is likely caused by GDB not removing the permanent
breakpoints from the target, leading to the inferior executing
the breakpoint instruction and tripping on a SIGSEGV.
gdb/ChangeLog:
2015-07-06 Luis Machado <lgustavo@codesourcery.com>
* breakpoint.c (remove_breakpoint_1): Don't handle permanent
breakpoints in a special way.
(remove_breakpoint): Likewise.
(mark_breakpoints_out): Likewise.
Some simulators don't handle permanent breakpoints properly and will
sometimes terminate when hitting such a breakpoint instruction or have
unwanted effects.
When a permanent breakpoint is inserted, GDB will not attempt to insert
other breakpoint locations on top of it, leading to the problem described
above.
By not marking permanent breakpoint locations as inserted, we allow the
insertion of breakpoint locations on top of the permanent ones, preventing
the simulators from running into that situation.
gdb/ChangeLog:
2015-06-17 Luis Machado <lgustavo@codesourcery.com>
* breakpoint.c (add_location_to_breakpoint): Don't mark permanent
locations as inserted.
Update and expand comment about permanent locations.
(bp_loc_is_permanent): Don't return 0 for bp_call_dummy.
Move comment to add_location_to_breakpoint.
(update_global_location_list): Don't error out if a permanent
breakpoint is not marked inserted.
Don't error out if a non-permanent breakpoint location is inserted on
top of a permanent breakpoint.
make_breakpoint_permanent is no longer used anywhere and can be
safely removed.
gdb/ChangeLog:
2015-06-17 Luis Machado <lgustavo@codesourcery.com>
* breakpoint.c (make_breakpoint_permanent): Remove unused
function.
* breakpoint.h (make_breakpoint_permanent): Remove declaration.
This patch fixes the "Format string required" error when trying to print
a dprintf on a now resolved, pending location when set via the MI interface
even if the format string is entered correctly.
This patch also adds a test case to check that issue called
mi-dprintf-pending.exp.
gdb/ChangeLog:
PR breakpoints/16465
* breakpoint.c (create_breakpoint): Save extra_string for
pending breakpoints.
gdb/testsuite/ChangeLog:
PR breakpoints/16465
* gdb.mi/mi-dprintf-pending.c: New file.
* gdb.mi/mi-dprintf-pending.exp: New test.
* gdb.mi/mi-dprintf-pendshr.c: New file.
We concluded that gdbarch_in_function_epilogue_p is misnamed, since it
returns true if the given PC is one instruction after the one that
destroyed the stack (which isn't necessarily inside an epilogue),
therefore it should be renamed to stack_frame_destroyed_p.
I also took the liberty of renaming the arch-specific implementations to
*_stack_frame_destroyed_p as well for consistency.
gdb:
2015-05-26 Martin Galvan <martin.galvan@tallertechnologies.com>
* amd64-tdep.c: Replace in_function_epilogue_p with
stack_frame_destroyed_p throughout.
* arch-utils.c: Ditto.
* arch-utils.h: Ditto.
* arm-tdep.c: Ditto.
* breakpoint.c: Ditto.
* gdbarch.sh: Ditto.
* hppa-tdep.c: Ditto.
* i386-tdep.c: Ditto.
* mips-tdep.c: Ditto.
* nios2-tdep.c: Ditto.
* rs6000-tdep.c: Ditto.
* s390-linux-tdep.c: Ditto.
* score-tdep.c: Ditto.
* sh-tdep.c: Ditto.
* sparc-tdep.c: Ditto.
* sparc-tdep.h: Ditto.
* sparc64-tdep.c: Ditto.
* spu-tdep.c: Ditto.
* tic6x-tdep.c: Ditto.
* tilegx-tdep.c: Ditto.
* xstormy16-tdep.c: Ditto.
* gdbarch.c, gdbarch.h: Re-generated.
Code in update_dprintf_command_list performed a duplicated memory
allocation which caused an obvious memory leak. This removes the
duplication.
gdb/
2015-04-19 Gabriel Krisman Bertazi <gabriel@krisman.be>
* breakpoint.c (update_dprintf_command_list): Remove duplicated
xmalloc.
Pedro Alves:
The commands that enables aren't even documented in the manual.
Judging from that, I assume that only wdb users would ever really
be using the --xdb switch.
I think it's time to drop "support" for the --xdb switch too. I
looked through the commands that that exposes, the only that looked
potentially interesting was "go", but then it's just an alias
for "tbreak+jump", which can easily be done with "define go...end".
I'd rather free up the "go" name for something potentially
more interesting (either run control, or maybe even unrelated,
e.g., for golang).
gdb/ChangeLog
2015-04-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* NEWS (Changes since GDB 7.9): Add removed -xdb.
* breakpoint.c (command_line_is_silent): Remove xdb_commands
conditional.
(_initialize_breakpoint): Remove xdb_commands for bc, ab, sb, db, ba
and lb.
* cli/cli-cmds.c (_initialize_cli_cmds): Remove xdb_commands for v and
va.
* cli/cli-decode.c (find_command_name_length): Remove xdb_commands
conditional.
* defs.h (xdb_commands): Remove declaration.
* f-valprint.c (_initialize_f_valprint): Remove xdb_commands for lc.
* guile/scm-cmd.c (command_classes): Remove xdb from comment.
* infcmd.c (run_no_args_command, go_command): Remove.
(_initialize_infcmd): Remove xdb_commands for S, go, g, R and lr.
* infrun.c (xdb_handle_command): Remove.
(_initialize_infrun): Remove xdb_commands for lz and z.
* main.c (xdb_commands): Remove variable.
(captured_main): Remove "xdb" from long_options.
(print_gdb_help): Remove --xdb from help.
* python/py-cmd.c (gdbpy_initialize_commands): Remove xdb from comment.
* source.c (_initialize_source): Remove xdb_commands for D, ld, / and ?.
* stack.c (backtrace_full_command, args_plus_locals_info)
(current_frame_command): Remove.
(_initialize_stack): Remove xdb_commands for t, T and l.
* symtab.c (_initialize_symtab): Remove xdb_commands for lf and lg.
* thread.c (_initialize_thread): Remove xdb_commands condition.
* tui/tui-layout.c (tui_toggle_layout_command)
(tui_toggle_split_layout_command, tui_handle_xdb_layout): Remove.
(_initialize_tui_layout): Remove xdb_commands for td and ts.
* tui/tui-regs.c (tui_scroll_regs_forward_command)
(tui_scroll_regs_backward_command): Remove.
(_initialize_tui_regs): Remove xdb_commands for fr, gr, sr, +r and -r.
* tui/tui-win.c (tui_xdb_set_win_height_command): Remove.
(_initialize_tui_win): Remove xdb_commands for U and w.
* utils.c (pagination_on_command, pagination_off_command): Remove.
(initialize_utils): Remove xdb_commands for am and sm.
gdb/doc/ChangeLog
2015-04-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.texinfo (Mode Options): Remove -xdb.
The "step" parameters of 'proceed' and 'resume' aren't really useful
as indication of whether run control wants to single-step the target,
as that information must already be retrievable from
currently_stepping. In fact, if currently_stepping disagrees with
whether we single-stepped the target, then things break. Thus instead
of having the same information in two places, this patch removes those
parameters.
Setting 'step_start_function' is the only user of proceed's 'step'
argument, other than passing the 'step' argument down to 'resume' and
debug log output. Move that instead to set_step_frame, where we
already set other related fields.
clear_proceed_status keeps its "step" parameter for now because it
needs to know which set of threads should have their state cleared,
and is called before the "stepping_command" flag is set.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
2015-03-24 Pedro Alves <palves@redhat.com>
* breakpoint.c (until_break_command): Adjust call to proceed.
* gdbthread.h (struct thread_control_state) <stepping_command>:
New field.
* infcall.c (run_inferior_call): Adjust call to proceed.
* infcmd.c (run_command_1, proceed_thread_callback, continue_1):
Adjust calls to proceed.
(set_step_frame): Set the current thread's step_start_function
here.
(step_once): Adjust calls to proceed.
(jump_command, signal_command, until_next_command)
(finish_backward, finish_forward, proceed_after_attach_callback)
(attach_command_post_wait): Adjust calls to proceed.
* infrun.c (proceed_after_vfork_done): Adjust call to proceed.
(do_target_resume): New function, factored out from ...
(resume): ... here. Remove 'step' parameter. Instead, check
currently_stepping to determine whether the thread should be
single-stepped.
(proceed): Remove 'step' parameter and don't set the thread's
step_start_function here. Adjust call to 'resume'.
(handle_inferior_event): Adjust calls to 'resume'.
(switch_back_to_stepped_thread): Use do_target_resume instead of
'resume'.
(keep_going): Adjust calls to 'resume'.
* infrun.h (proceed): Remove 'step' parameter.
(resume): Likewise.
* windows-nat.c (do_initial_windows_stuff): Adjust call to
'resume'.
* mi/mi-main.c (proceed_thread): Adjust call to 'proceed'.
When setting a pending breakpoint with a thread condition while using
the mi interface, the thread condition would be lost by gdb when the breakpoint
was resolved.
This patch fixes this behavior by setting the thread condition properly in the
mi case.
Also, this patch modifies the mi-pending test case to test for this issue and
removes some unneeded code in the testcase and dependency on stdio.
gdb/Changelog:
PR breakpoints/16466
* breakpoint.c (create_breakpoint): Set thread on breakpoint struct.
gdb/testsuite/ChangeLog:
PR breakpoints/16466
* gdb.mi/Makefile.in: Add mi-pendshr2.sl to cleanup.
* gdb.mi/mi-pending.c (thread_func): New function.
(int main): Add threading support required.
* gdb.mi/mi-pending.exp: Add tests for this issue.
* gdb.mi/mi-pendshr.c (pendfunc1): Remove stdio dependency.
(pendfunc2): Remove stdio dependency.
* gdb.mi/mi-pendshr2.c: New file.
This patch changes the heuristic the linespec lexer uses to
detect a keyword in the input stream.
Currently, the heuristic is: a word is a keyword if it
1) points to a string that is a keyword
2) is followed by a non-identifier character
This is strictly more correct than using whitespace. For example,
it allows constructs such as "break foo if(i == 1)". However,
find_condition_and_thread in breakpoint.c does not support this expanded
usage. It requires whitespace to follow the keyword.
The proposed new heuristic is: a word is a keyword if it
1) points to a string that is a keyword
2) is followed by whitespace
3) is not followed by another keyword string followed by whitespace
This additional complexity allows constructs such as
"break thread thread 3" and "break thread 3". In the former case,
the actual location is a symbol named "thread" to be set on thread #3.
In the later case, the location is NULL, i.e., the default location,
to be set on thread #3.
In order to pass all the new tests added here, I've also had to add a
new feature to parse_breakpoint_sals, which expands recognition of the
default location to keywords other than "if", which is the only keyword
currently permitted with the default (NULL) location, but there is no
reason to exclude other keywords.
Consequently, it will be possible to use "break thread 1" or
"break task 1".
In addition to all of this, it is now possible to remove the keyword_ok
state from the linespec parser.
gdb/ChangeLog
* breakpoint.c (parse_breakpoint_sals): Use
linespec_lexer_lex_keyword to ascertain if the user specified
a NULL location.
* linespec.c [IF_KEYWORD_INDEX]: Define.
(linespec_lexer_lex_keyword): Export.
(struct ls_parser) <keyword_ok>: Remove.
A keyword is only a keyword if not followed by another keyword.
(linespec_lexer_lex_one): Remove keyword_ok handling.
Add comment explaining why the parsing stream is not advanced
when a keyword is seen.
(parse_linespec): Remove parser->keyword_ok.
* linespec.h (linespec_lexer_lex_keyword): Add declaration.
gdb/testsuite/ChangeLog
* gdb.linespec/keywords.c: New file.
* gdb.linespec/keywords.exp: New file.
This commits cleans up the gdb/breakpoint.c file and moves everything
that is related to the 'catch syscall' command to the new file
gdb/break-catch-syscall.c. This is just code movement, and the only
new part is the adjustment needed on 'catching_syscall_number' to use
the new 'breakpoint_find_if' function insted of relying on the
ALL_BREAKPOINTS macro.
Tested by running the 'gdb.base/catch-syscall.exp' testcase.
gdb/ChangeLog:
2015-03-11 Sergio Durigan Junior <sergiodj@redhat.com>
* Makefile.in (SFILES): New source break-catch-syscall.c.
(COMMON_OBS): New object break-catch-syscall.o.
* break-catch-syscall.c: New file.
* breakpoint.c: Remove inclusion of "xml-syscall.h".
(syscall_catchpoint_p): Move declaration to break-catch-syscall.c
(struct syscall_catchpoint): Likewise.
(dtor_catch_syscall): Likewise.
(catch_syscall_inferior_data): Likewise.
(struct catch_syscall_inferior_data): Likewise.
(get_catch_syscall_inferior_data): Likewise.
(catch_syscall_inferior_data_cleanup): Likewise.
(insert_catch_syscall): Likewise.
(remove_catch_syscall): Likewise.
(breakpoint_hit_catch_syscall): Likewise.
(print_it_catch_syscall): Likewise.
(print_one_catch_syscall): Likewise.
(print_mention_catch_syscall): Likewise.
(print_recreate_catch_syscall): Likewise.
(catch_syscall_breakpoint_ops): Likewise.
(syscall_catchpoint_p): Likewise.
(create_syscall_event_catchpoint): Likewise.
(catch_syscall_split_args): Likewise.
(catch_syscall_command_1): Likewise.
(is_syscall_catchpoint_enabled): Likewise.
(catch_syscall_enabled): Likewise.
(catching_syscall_number): Likewise.
(catch_syscall_completer): Likewise.
(clear_syscall_counts): Likewise.
(initialize_breakpoint_ops): Move initialization of syscall
catchpoints to break-catch-syscall.c.
(_initialize_breakpoint): Move code related to syscall catchpoints
to break-catch-syscall.c.
This commit implements the 'breakpoint_find_if' function, which allows
code external to gdb/breakpoint.c to iterate through the list of
'struct breakpoint *'. This is needed in order to create the
'gdb/break-catch-syscall.c' file, because one of its functions
(catching_syscall_number) needs to do this iteration.
My first thought was to share the ALL_BREAKPOINTS* macros on
gdb/breakpoint.h, but they use a global variable local to
gdb/breakpoint.c, and I did not want to share that variable. So, in
order to keep the minimal separation, I decided to implement this
way of iterating through the existing 'struct breakpoint *'.
This function was based on BFD's bfd_sections_find_if. If the
user-provided function returns 0, the iteration proceeds. Otherwise,
the iteration stops and the function returns the 'struct breakpoint *'
that is being processed. This means that the return value of this
function can be either NULL or a pointer to a 'struct breakpoint'.
gdb/ChangeLog:
2015-03-11 Sergio Durigan Junior <sergiodj@redhat.com>
* breakpoint.c (breakpoint_find_if): New function.
* breakpoint.h (breakpoint_find_if): New prototype.
All these were caught by actually making TRY/CATCH use try/catch
behind the scenes, which then resulted in the build failing (on x86_64
Fedora 20) because there was code between the try and catch blocks.
gdb/ChangeLog:
2015-03-07 Pedro Alves <palves@redhat.com>
* breakpoint.c (save_breakpoints): Adjust to avoid code between
TRY and CATCH.
* gdbtypes.c (safe_parse_type): Remove empty line.
(types_deeply_equal):
* guile/scm-frame.c (gdbscm_frame_name):
* linux-thread-db.c (find_new_threads_once):
* python/py-breakpoint.c (bppy_get_commands):
* record-btrace.c (record_btrace_insert_breakpoint)
(record_btrace_remove_breakpoint, record_btrace_start_replaying)
(record_btrace_start_replaying): Adjust to avoid code between TRY
and CATCH.
This patch splits the TRY_CATCH macro into three, so that we go from
this:
~~~
volatile gdb_exception ex;
TRY_CATCH (ex, RETURN_MASK_ERROR)
{
}
if (ex.reason < 0)
{
}
~~~
to this:
~~~
TRY
{
}
CATCH (ex, RETURN_MASK_ERROR)
{
}
END_CATCH
~~~
Thus, we'll be getting rid of the local volatile exception object, and
declaring the caught exception in the catch block.
This allows reimplementing TRY/CATCH in terms of C++ exceptions when
building in C++ mode, while still allowing to build GDB in C mode
(using setjmp/longjmp), as a transition step.
TBC, after this patch, is it _not_ valid to have code between the TRY
and the CATCH blocks, like:
TRY
{
}
// some code here.
CATCH (ex, RETURN_MASK_ERROR)
{
}
END_CATCH
Just like it isn't valid to do that with C++'s native try/catch.
By switching to creating the exception object inside the CATCH block
scope, we can get rid of all the explicitly allocated volatile
exception objects all over the tree, and map the CATCH block more
directly to C++'s catch blocks.
The majority of the TRY_CATCH -> TRY+CATCH+END_CATCH conversion was
done with a script, rerun from scratch at every rebase, no manual
editing involved. After the mechanical conversion, a few places
needed manual intervention, to fix preexisting cases where we were
using the exception object outside of the TRY_CATCH block, and cases
where we were using "else" after a 'if (ex.reason) < 0)' [a CATCH
after this patch]. The result was folded into this patch so that GDB
still builds at each incremental step.
END_CATCH is necessary for two reasons:
First, because we name the exception object in the CATCH block, which
requires creating a scope, which in turn must be closed somewhere.
Declaring the exception variable in the initializer field of a for
block, like:
#define CATCH(EXCEPTION, mask) \
for (struct gdb_exception EXCEPTION; \
exceptions_state_mc_catch (&EXCEPTION, MASK); \
EXCEPTION = exception_none)
would avoid needing END_CATCH, but alas, in C mode, we build with C90,
which doesn't allow mixed declarations and code.
Second, because when TRY/CATCH are wired to real C++ try/catch, as
long as we need to handle cleanup chains, even if there's no CATCH
block that wants to catch the exception, we need for stop at every
frame in the unwind chain and run cleanups, then rethrow. That will
be done in END_CATCH.
After we require C++, we'll still need TRY/CATCH/END_CATCH until
cleanups are completely phased out -- TRY/CATCH in C++ mode will
save/restore the current cleanup chain, like in C mode, and END_CATCH
catches otherwise uncaugh exceptions, runs cleanups and rethrows, so
that C++ cleanups and exceptions can coexist.
IMO, this still makes the TRY/CATCH code look a bit more like a
newcomer would expect, so IMO worth it even if we weren't considering
C++.
gdb/ChangeLog.
2015-03-07 Pedro Alves <palves@redhat.com>
* common/common-exceptions.c (struct catcher) <exception>: No
longer a pointer to volatile exception. Now an exception value.
<mask>: Delete field.
(exceptions_state_mc_init): Remove all parameters. Adjust.
(exceptions_state_mc): No longer pop the catcher here.
(exceptions_state_mc_catch): New function.
(throw_exception): Adjust.
* common/common-exceptions.h (exceptions_state_mc_init): Remove
all parameters.
(exceptions_state_mc_catch): Declare.
(TRY_CATCH): Rename to ...
(TRY): ... this. Remove EXCEPTION and MASK parameters.
(CATCH, END_CATCH): New.
All callers adjusted.
gdb/gdbserver/ChangeLog:
2015-03-07 Pedro Alves <palves@redhat.com>
Adjust all callers of TRY_CATCH to use TRY/CATCH/END_CATCH
instead.
This commit introduces a new inline common function "startswith"
which takes two string arguments and returns nonzero if the first
string starts with the second. It also updates the 295 places
where this logic was written out longhand to use the new function.
gdb/ChangeLog:
* common/common-utils.h (startswith): New inline function.
All places where this logic was used updated to use the above.
The moribund locations heuristics are problematic. This patch teaches
GDB about targets that can reliably tell whether a trap was caused by
a software or hardware breakpoint, and thus don't need moribund
locations, thus bypassing all the problems that mechanism has.
The non-stop-fair-events.exp test is frequently failing currently.
E.g., see https://sourceware.org/ml/gdb-testers/2015-q1/msg03148.html.
The root cause is a fundamental problem with moribund locations. For
example, the stepped_breakpoint logic added by af48d08f breaks in this
case (which is what happens with that test):
- Step thread A, no breakpoint is set at PC.
- The kernel doesn't schedule thread A yet.
- Insert breakpoint at A's PC, for some reason (e.g., a step-resume
breakpoint for thread B).
- Kernel finally schedules thread A.
- thread A's stepped_breakpoint flag is not set, even though it now
stepped a breakpoint instruction.
- adjust_pc_after_break gets the PC wrong, because PC == PREV_PC, but
stepped_breakpoint is not set.
We needed the stepped_breakpoint logic to workaround moribund
locations, because otherwise adjust_pc_after_break could apply an
adjustment when it shouldn't just because there _used_ to be a
breakpoint at PC (a moribund breakpoint location). For example, on
x86, that's wrong if the thread really hasn't executed an int3, but
instead executed some other 1-byte long instruction. Getting the PC
adjustment wrong of course leads to the inferior executing the wrong
instruction.
Other problems with moribund locations are:
- if a true SIGTRAP happens to be raised when the program is
executing the PC that used to have a breakpoint, GDB will assume
that is a trap for a breakpoint that has recently been removed, and
thus we miss reporting the random signal to the user.
- to minimize that, we get rid of moribund location after a while.
That while is defined as just a certain number of events being
processed. That number of events sometimes passes by before a
delayed breakpoint is processed, and GDB confuses the trap for a
random signal, thus reporting the random trap. Once the user
resumes the thread, the program crashes because the PC was not
adjusted...
The fix for all this is to bite the bullet and get rid of heuristics
and instead rely on the target knowing accurately what caused the
SIGTRAP. The target/kernel/stub is in the best position to know what
that, because it can e.g. consult priviledged CPU flags GDB has no
access to, or by knowing which exception vector entry was called when
the instruction trapped, etc. Most debug APIs I've seen to date
report breakpoint hits as a distinct event in some fashion. For
example, on the Linux kernel, whether a breakpoint was executed is
exposed to userspace in the si_code field of the SIGTRAP's siginfo.
On Windows, the debug API reports a EXCEPTION_BREAKPOINT exception
code.
We needed to keep around deleted breakpoints in an on-the-side list
(the moribund locations) for two main reasons:
- Know that a SIGTRAP actually is a delayed event for a hit of a
breakpoint that was removed before the event was processed, and
thus should not be reported as a random signal.
- So we still do the decr_pc_after_break adjustment in that case, so
that the thread is resumed at the correct address.
In the new model, if GDB processes an event the target tells is a
breakpoint trap, and GDB doesn't find the corresponding breakpoint in
its breakpoint tables, it means that event is a delayed event for a
breakpoint that has since been removed, and thus the event should be
ignored.
For the decr_pc_after_after issue, it ends up being much simpler that
on targets that can reliably tell whether a breakpoint trapped, for
the breakpoint trap to present the PC already adjusted. Proper
multi-threading support already implies that targets needs to be doing
decr_pc_after_break adjustment themselves, otherwise for example, in
all-stop if two threads hit a breakpoint simultaneously, and the user
does "info threads", he'll see the non-event thread that hit the
breakpoint stopped at the wrong PC.
This way (target adjusts) also ends up eliminating the need for some
awkward re-incrementing of the PC in the record-full and Linux targets
that we do today, and the need for the target_decr_pc_after_break
hook.
If the target always adjusts, then there's a case where GDB needs to
re-increment the PC. Say, on x86, an "int3" instruction that was
explicitly written in the program traps. In this case, GDB should
report a random SIGTRAP signal to the user, with the PC pointing at
the instruction past the int3, just like if GDB was not debugging the
program. The user may well decide to pass the SIGTRAP to the program
because the program being debugged has a SIGTRAP handler that handles
its own breakpoints, and expects the PC to be unadjusted.
Tested on x86-64 Fedora 20.
gdb/ChangeLog:
2015-03-04 Pedro Alves <palves@redhat.com>
* breakpoint.c (need_moribund_for_location_type): New function.
(bpstat_stop_status): Don't skipping checking moribund locations
of breakpoint types which the target tell caused a stop.
(program_breakpoint_here_p): New function, factored out from ...
(bp_loc_is_permanent): ... this.
(update_global_location_list): Don't create a moribund location if
the target supports reporting stops of the type of the removed
breakpoint.
* breakpoint.h (program_breakpoint_here_p): New declaration.
* infrun.c (adjust_pc_after_break): Return early if the target has
already adjusted the PC. Add comments.
(handle_signal_stop): If nothing explains a signal, and the target
tells us the stop was caused by a software breakpoint, check if
there's a breakpoint instruction in the memory. If so, adjust the
PC before presenting the stop to the user. Otherwise, ignore the
trap. If nothing explains a signal, and the target tells us the
stop was caused by a hardware breakpoint, ignore the trap.
* target.h (struct target_ops) <to_stopped_by_sw_breakpoint,
to_supports_stopped_by_sw_breakpoint, to_stopped_by_hw_breakpoint,
to_supports_stopped_by_hw_breakpoint>: New fields.
(target_stopped_by_sw_breakpoint)
(target_supports_stopped_by_sw_breakpoint)
(target_stopped_by_hw_breakpoint)
(target_supports_stopped_by_hw_breakpoint): Define.
* target-delegates.c: Regenerate.
This patch adds a new type of probe to GDB: the DTrace USDT probes. The new
type is added by providing functions implementing all the entries of the
`probe_ops' structure defined in `probe.h'. The implementation is
self-contained and does not depend on DTrace source code in any way.
gdb/ChangeLog:
2015-02-7 Jose E. Marchesi <jose.marchesi@oracle.com>
* breakpoint.c (BREAK_ARGS_HELP): Help string updated to mention
the -probe-dtrace new vpossible value for PROBE_MODIFIER.
* configure.ac (CONFIG_OBS): dtrace-probe.o added if BFD can
handle ELF files.
* Makefile.in (SFILES): dtrace-probe.c added.
* configure: Regenerate.
* dtrace-probe.c: New file.
(SHT_SUNW_dof): New constant.
(dtrace_probe_type): New enum.
(dtrace_probe_arg): New struct.
(dtrace_probe_arg_s): New typedef.
(struct dtrace_probe_enabler): New struct.
(dtrace_probe_enabler_s): New typedef.
(dtrace_probe): New struct.
(dtrace_probe_is_linespec): New function.
(dtrace_dof_sect_type): New enum.
(dtrace_dof_dofh_ident): Likewise.
(dtrace_dof_encoding): Likewise.
(DTRACE_DOF_ENCODE_LSB): Likewise.
(DTRACE_DOF_ENCODE_MSB): Likewise.
(dtrace_dof_hdr): New struct.
(dtrace_dof_sect): Likewise.
(dtrace_dof_provider): Likewise.
(dtrace_dof_probe): Likewise.
(DOF_UINT): New macro.
(DTRACE_DOF_PTR): Likewise.
(DTRACE_DOF_SECT): Likewise.
(dtrace_process_dof_probe): New function.
(dtrace_process_dof): Likewise.
(dtrace_build_arg_exprs): Likewise.
(dtrace_get_arg): Likewise.
(dtrace_get_probes): Likewise.
(dtrace_get_probe_argument_count): Likewise.
(dtrace_can_evaluate_probe_arguments): Likewise.
(dtrace_evaluate_probe_argument): Likewise.
(dtrace_compile_to_ax): Likewise.
(dtrace_probe_destroy): Likewise.
(dtrace_gen_info_probes_table_header): Likewise.
(dtrace_gen_info_probes_table_values): Likewise.
(dtrace_probe_is_enabled): Likewise.
(dtrace_probe_ops): New variable.
(info_probes_dtrace_command): New function.
(_initialize_dtrace_probe): Likewise.
(dtrace_type_name): Likewise.
In C, we can forward declare static structure instances. That doesn't
work in C++ though. C++ treats these as definitions. So then the
compiler complains about symbol redefinition, like:
src/gdb/elfread.c:1569:29: error: redefinition of ‘const sym_fns elf_sym_fns_lazy_psyms’
src/gdb/elfread.c:53:29: error: ‘const sym_fns elf_sym_fns_lazy_psyms’ previously declared here
The intent of static here is naturally to avoid making these objects
visible outside the compilation unit. The equivalent in C++ would be
to instead define the objects in the anonymous namespace. But given
that it's desirable to leave the codebase compiling as both C and C++
for a while, this just makes the objects extern.
(base_breakpoint_ops is already declared in breakpoint.h, so we can
just remove the forward declare from breakpoint.c)
gdb/ChangeLog:
2015-02-11 Tom Tromey <tromey@redhat.com>
Pedro Alves <palves@redhat.com>
* breakpoint.c (base_breakpoint_ops): Delete.
* dwarf2loc.c (dwarf_expr_ctx_funcs): Make extern.
* elfread.c (elf_sym_fns_gdb_index, elf_sym_fns_lazy_psyms): Make extern.
* guile/guile.c (guile_extension_script_ops, guile_extension_ops): Make extern.
* ppcnbsd-tdep.c (ppcnbsd2_sigtramp): Make extern.
* python/py-arch.c (arch_object_type): Make extern.
* python/py-block.c (block_syms_iterator_object_type): Make extern.
* python/py-bpevent.c (breakpoint_event_object_type): Make extern.
* python/py-cmd.c (cmdpy_object_type): Make extern.
* python/py-continueevent.c (continue_event_object_type)
* python/py-event.h (GDBPY_NEW_EVENT_TYPE): Remove 'qual'
parameter. Update all callers.
* python/py-evtregistry.c (eventregistry_object_type): Make extern.
* python/py-exitedevent.c (exited_event_object_type): Make extern.
* python/py-finishbreakpoint.c (finish_breakpoint_object_type): Make extern.
* python/py-function.c (fnpy_object_type): Make extern.
* python/py-inferior.c (inferior_object_type, membuf_object_type): Make extern.
* python/py-infevents.c (call_pre_event_object_type)
(inferior_call_post_event_object_type).
(memory_changed_event_object_type): Make extern.
* python/py-infthread.c (thread_object_type): Make extern.
* python/py-lazy-string.c (lazy_string_object_type): Make extern.
* python/py-linetable.c (linetable_entry_object_type)
(linetable_object_type, ltpy_iterator_object_type): Make extern.
* python/py-newobjfileevent.c (new_objfile_event_object_type)
(clear_objfiles_event_object_type): Make extern.
* python/py-objfile.c (objfile_object_type): Make extern.
* python/py-param.c (parmpy_object_type): Make extern.
* python/py-progspace.c (pspace_object_type): Make extern.
* python/py-signalevent.c (signal_event_object_type): Make extern.
* python/py-symtab.c (symtab_object_type, sal_object_type): Make extern.
* python/py-type.c (type_object_type, field_object_type)
(type_iterator_object_type): Make extern.
* python/python.c (python_extension_script_ops)
(python_extension_ops): Make extern.
* stap-probe.c (stap_probe_ops): Make extern.
Typing "enable count" by itself crashes GDB. Also, if you omit the
breakpoint number/range, the error message is not very clear:
(gdb) enable count 2
warning: bad breakpoint number at or near ''
(gdb) enable count
Segmentation fault (core dumped)
With this patch, the error messages are slightly more helpful:
(gdb) enable count 2
Argument required (one or more breakpoint numbers).
(gdb) enable count
Argument required (hit count).
gdb/ChangeLog:
PR gdb/15678
* breakpoint.c (map_breakpoint_numbers): Check for empty args
string.
(enable_count_command): Check args for NULL value.
gdb/testsuite/ChangeLog:
PR gdb/15678
* gdb.base/ena-dis-br.exp: Test "enable count" for bad user input.
Executing a gdb script that runs the inferior (from the command line
with -x), and has it hit breakpoints with breakpoint commands that
themselves run the target, is currently broken on async targets
(Linux, remote).
While we're executing a command list or a script, we force the
interpreter to be sync, which results in some functions nesting an
event loop and waiting for the target to stop, instead of returning
immediately and having the top level event loop handle the stop.
The issue with this bug is simply that bpstat_do_actions misses
checking whether the interpreter is sync. When we get here, in the
case of executing a script (or, when the interpreter is sync), the
program has already advanced to the next breakpoint, through
maybe_wait_sync_command_done. We need to process its breakpoints
immediately, just like with a sync target.
Tested on x86_64 Fedora 20.
gdb/
2015-01-14 Pedro Alves <palves@redhat.com>
PR gdb/17525
* breakpoint.c: Include "interps.h".
(bpstat_do_actions_1): Also check whether the interpreter is
async.
gdb/testsuite/
2015-01-14 Pedro Alves <palves@redhat.com>
Joel Brobecker <brobecker@adacore.com>
PR gdb/17525
* gdb.base/bp-cmds-execution-x-script.c: New file.
* gdb.base/bp-cmds-execution-x-script.exp: New file.
* gdb.base/bp-cmds-execution-x-script.gdb: New file.
Running the testsuite with a series that reimplements user-visible
all-stop behavior on top of a target running in non-stop mode revealed
problems related to event starvation avoidance.
For example, I see
gdb.threads/signal-while-stepping-over-bp-other-thread.exp failing.
What happens is that GDB core never gets to see the signal event. It
ends up processing the events for the same threads over an over,
because Linux's waitpid(-1, ...) returns that first task in the task
list that has an event, starving threads on the tail of the task list.
So I wrote a non-stop mode test originally inspired by
signal-while-stepping-over-bp-other-thread.exp, to stress this
independently of all-stop on top of non-stop. Fixing it required the
changes described below. The test will be added in a following
commit.
1) linux-nat.c has code in place that picks an event LWP at random out
of all that have had events. This is because on the kernel side,
"waitpid(-1, ...)" just walks the task list linearly looking for the
first that had an event. But, this code is currently only used in
all-stop mode. So with a multi-threaded program that has multiple
events triggering debug events in parallel, GDB ends up starving some
threads.
To make the event randomization work in non-stop mode too, the patch
makes us pull out all the already pending events on the kernel side,
with waitpid, before deciding which LWP to report to the core.
There's some code in linux_wait that takes care of leaving events
pending if they were for LWPs the caller is not interested in. The
patch moves that to linux_nat_filter_event, so that we only have one
place that leaves events pending. With that in place, conceptually,
the flow is simpler and more normalized:
#1 - walk the LWP list looking for an LWP with a pending event to report.
#2 - if no pending event, pull events out of the kernel, and store
them in the LWP structures as pending.
#3- goto #1.
2) Then, currently the event randomization code only considers SIGTRAP
(or trap-like) events. That means that if e.g., have have multiple
threads stepping in parallel that hit a breakpoint that needs stepping
over, and one gets a signal, the signal may end up never getting
processed, because GDB will always be giving priority to the SIGTRAPs.
The patch fixes this by making the randomization code consider all
kinds of pending events.
3) If multiple threads hit a breakpoint, we report one of those, and
"cancel" the others. Cancelling means decrementing the PC, and
discarding the event. If the next time the LWP is resumed the
breakpoint is still installed, the LWP should hit it again, and we'll
report the hit then. The problem I found is that this delays threads
from advancing too much, with the kernel potentially ending up
scheduling the same threads over and over, and others not advancing.
So the patch switches away from cancelling the breakpoints, and
instead remembering that the LWP had stopped for a breakpoint. If on
resume the breakpoint is still installed, we report it. If it's no
longer installed, we discard the pending event then. This is actually
how GDBserver used to handle this before d50171e4 (Teach linux
gdbserver to step-over-breakpoints), but with the difference that back
then we'd delay adjusting the PC until resuming, which made it so that
"info threads" could wrongly see threads with unadjusted PCs.
gdb/
2015-01-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (hardware_breakpoint_inserted_here_p): New
function.
* breakpoint.h (hardware_breakpoint_inserted_here_p): New
declaration.
* linux-nat.c (linux_nat_status_is_event): Move higher up in file.
(linux_resume_one_lwp): Store the thread's PC. Adjust to clear
stop_reason.
(check_stopped_by_watchpoint): New function.
(save_sigtrap): Reimplement.
(linux_nat_stopped_by_watchpoint): Adjust.
(linux_nat_lp_status_is_event): Delete.
(stop_wait_callback): Only call save_sigtrap after storing the
pending status.
(status_callback): If the thread had been stopped for a breakpoint
that has since been removed, discard the event and resume the LWP.
(count_events_callback, select_event_lwp_callback): Use
lwp_status_pending_p instead of linux_nat_lp_status_is_event.
(cancel_breakpoint): Rename to ...
(check_stopped_by_breakpoint): ... this. Record whether the LWP
stopped for a software breakpoint or hardware breakpoint.
(select_event_lwp): Only give preference to the stepping LWP in
all-stop mode. Adjust comments.
(stop_and_resume_callback): Remove references to new_pending_p.
(linux_nat_filter_event): Likewise. Leave exit events of the
leader thread pending here. Handle signal short circuiting here.
Only call save_sigtrap after storing the pending waitstatus.
(linux_nat_wait_1): Remove 'retry' label. Remove references to
new_pending. Don't handle leaving events the caller is not
interested in pending here, nor handle signal short-circuiting
here. Also give equal priority to all LWPs that have had events
in non-stop mode. If reporting a software breakpoint event,
unadjust the LWP's PC.
* linux-nat.h (enum lwp_stop_reason): New.
(struct lwp_info) <stop_pc>: New field.
(struct lwp_info) <stopped_by_watchpoint>: Delete field.
(struct lwp_info) <stop_reason>: New field.
* x86-linux-nat.c (x86_linux_prepare_to_resume): Adjust.
Factor out common code, and use the more efficient
ALL_BP_LOCATIONS_AT_ADDR.
gdb/
2015-01-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (bp_location_inserted_here_p): New function,
factored out from ...
(breakpoint_inserted_here_p): ... here. Use
ALL_BP_LOCATIONS_AT_ADDR.
(software_breakpoint_inserted_here_p): Use
bp_location_inserted_here_p and ALL_BP_LOCATIONS_AT_ADDR.
On Linux native, if dprintfs are inserted when detaching, they are left
in the inferior which causes it to crash from a SIGTRAP. It also happens
with dprintfs on remote targets, when set disconnected-dprintf is off.
The rationale of the line modified by the patch was to leave dprintfs
inserted in order to support disconnected dprintfs. However, not all
dprintfs are persistent. Also, there's no reason other kinds of
breakpoints can't be persistent either. So this replaces the bp_dprintf
check with a check on whether the location is persistent.
bl->target_info.persist will be 1 only if disconnected-dprintf is on and
we are debugging a remote target. On native, it will always be 0,
regardless of the value of disconnected-dprintf. This makes sense, since
disconnected dprintfs are not supported by the native target.
One issue about the test is that it does not pass when using
--target_board=native-extended-gdbserver, partly due to bug 17302 [1].
One quick hack I tried for this was to add a useless "next" between the
call to getpid() and detach, which avoids the bug. There is still one
case where the test fails, and that is with:
- breakpoint always-inserted on
- dprintf-style agent
- disconnected-dprintf on
What happens is that my detach does not actually detach the process,
because some persistent commands (the disconnected dprintf) is present.
However since gdbserver is ran with --once, when gdb disconnects,
gdbserver goes down and takes with it all the processes it spawned and
that are still under its control (which includes my test process).
When the test checks if the test process is still alive, it obvisouly
fails. Investigating about that led me to ask a question on the ML [2]
about the behavior of detach.
Until the remote case is sorted out, the problematic test is marked as
KFAIL.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=17302
[2] https://sourceware.org/ml/gdb/2014-08/msg00115.html
gdb/Changelog:
PR breakpoints/17012
* breakpoint.c (remove_breakpoints_pid): Skip removing
breakpoint if it is marked as persistent.
gdb/testsuite/ChangeLog:
PR breakpoints/17012
* gdb.base/dprintf-detach.c: New file.
* gdb.base/dprintf-detach.exp: New file.
A recent change...
commit 1a853c5224
Date: Wed Nov 12 10:10:49 2014 +0000
Subject: make "permanent breakpoints" per location and disableable
... broke function calls on sparc-elf when running over QEMU. Any
function call should demonstrate the problem.
For instance, seen from the debugger:
(gdb) call pn(1234)
[Inferior 1 (Remote target) exited normally]
The program being debugged exited while in a function called from GDB.
Evaluation of the expression containing the function
And seen from QEMU:
qemu: fatal: Trap 0x02 while interrupts disabled, Error state
[register dump removed]
What happens in this case is that GDB sets the inferior function call
by not only creating the dummy frame, but also writing a breakpoint
instruction at the return address for our function call. See infcall.c:
/* Write a legitimate instruction at the point where the infcall
breakpoint is going to be inserted. While this instruction
is never going to be executed, a user investigating the
memory from GDB would see this instruction instead of random
uninitialized bytes. We chose the breakpoint instruction
as it may look as the most logical one to the user and also
valgrind 3.7.0 needs it for proper vgdb inferior calls.
If software breakpoints are unsupported for this target we
leave the user visible memory content uninitialized. */
bp_addr_as_address = bp_addr;
bp_bytes = gdbarch_breakpoint_from_pc (gdbarch, &bp_addr_as_address,
&bp_size);
if (bp_bytes != NULL)
write_memory (bp_addr_as_address, bp_bytes, bp_size);
This instruction triggers a change introduced by the commit above,
where we consider bp locations as being permanent breakpoints
if there is already a breakpoint instruction at that address:
+ if (bp_loc_is_permanent (loc))
+ {
+ loc->inserted = 1;
+ loc->permanent = 1;
+ }
As a result, when resuming the program's execution for the inferior
function call, GDB decides that it does not need to insert a breakpoint
at this address, expecting the target to just report a SIGTRAP when
trying to execute that instruction.
But unfortunately for us, at least some versions of QEMU for SPARC
just terminate the execution entirely instead of reporting a breakpoint,
thus producing the behavior reported here.
Although it appears like QEMU might be misbehaving and should therefore
be fixed (to be verified) from the user's point of view, the recent
change does introduce a regression. So this patch tries to mitigate
a bit the damage by handling such infcall breakpoints as special and
making sure that they are never considered permanent, thus restoring
the previous behavior specifically for those breakpoints.
The option of not writing the breakpoint instructions in the first
place was considered, and would probably work also. But the comment
associated to it seems to indicate that there is still reason to
keep it.
gdb/ChangeLog:
* breakpoint.c (bp_loc_is_permanent): Return 0 if LOC corresponds
to a bp_call_dummy breakpoint type.
Tested on x86_64-linux. Also testing on sparc-elf/QEMU using
AdaCore's testsuite.
This patch intends to partially fix PR breakpoints/10737, which is
about making the syscall information (for the "catch syscall" command)
be per-arch, instead of global. This is not a full fix because of the
other issues pointed by Pedro here:
<https://sourceware.org/bugzilla/show_bug.cgi?id=10737#c5>
However, I consider it a good step towards the real fix. It will also
help me fix <https://sourceware.org/bugzilla/show_bug.cgi?id=17402>.
What this patch does, basically, is move the "syscalls_info"
struct to gdbarch. Currently, the syscall information is stored in a
global variable inside gdb/xml-syscall.c, which means that there is no
easy way to correlate this info with the current target or
architecture being used, for example. This causes strange behaviors,
because the syscall info is not re-read when the arch changes. For
example, if you put a syscall catchpoint in syscall 5 on i386 (syscall
open), and then load a x86_64 program on GDB and put the same syscall
5 there (fstat on x86_64), you will still see that GDB tells you that
it is catching "open", even though it is not. With this patch, GDB
correctly says that it will be catching fstat syscalls.
(gdb) set architecture i386
The target architecture is assumed to be i386
(gdb) catch syscall 5
Catchpoint 1 (syscall 'open' [5])
(gdb) set architecture i386:x86-64
The target architecture is assumed to be i386:x86-64
(gdb) catch syscall 5
Catchpoint 2 (syscall 'open' [5])
But with the patch:
(gdb) set architecture i386
The target architecture is assumed to be i386
(gdb) catch syscall 5
Catchpoint 1 (syscall 'open' [5])
(gdb) set architecture i386:x86-64
The target architecture is assumed to be i386:x86-64
(gdb) catch syscall 5
Catchpoint 2 (syscall 'fstat' [5])
As I said, there are still some problems on the "catch syscall"
mechanism, because (for example) the user should be able to "catch
syscall open" on i386, and then expect "open" to be caught also on
x86_64. Currently, it doesn't work. I intend to work on this later.
gdb/
2014-11-20 Sergio Durigan Junior <sergiodj@redhat.com>
PR breakpoints/10737
* amd64-linux-tdep.c (amd64_linux_init_abi_common): Adjust call to
set_xml_syscall_file_name to provide gdbarch.
* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
* bfin-linux-tdep.c (bfin_linux_init_abi): Likewise.
* breakpoint.c (print_it_catch_syscall): Adjust call to
get_syscall_by_number to provide gdbarch.
(print_one_catch_syscall): Likewise.
(print_mention_catch_syscall): Likewise.
(print_recreate_catch_syscall): Likewise.
(catch_syscall_split_args): Adjust calls to get_syscall_by_number
and get_syscall_by_name to provide gdbarch.
(catch_syscall_completer): Adjust call to get_syscall_names to
provide gdbarch.
* gdbarch.c: Regenerate.
* gdbarch.h: Likewise.
* gdbarch.sh: Forward declare "struct syscalls_info".
(xml_syscall_file): New variable.
(syscalls_info): Likewise.
* i386-linux-tdep.c (i386_linux_init_abi): Adjust call to
set_xml_syscall_file_name to provide gdbarch.
* mips-linux-tdep.c (mips_linux_init_abi): Likewise.
* ppc-linux-tdep.c (ppc_linux_init_abi): Likewise.
* s390-linux-tdep.c (s390_gdbarch_init): Likewise.
* sparc-linux-tdep.c (sparc32_linux_init_abi): Likewise.
* sparc64-linux-tdep.c (sparc64_linux_init_abi): Likewise.
* xml-syscall.c: Include gdbarch.h.
(set_xml_syscall_file_name): Accept gdbarch parameter.
(get_syscall_by_number): Likewise.
(get_syscall_by_name): Likewise.
(get_syscall_names): Likewise.
(my_gdb_datadir): Delete global variable.
(struct syscalls_info) <my_gdb_datadir>: New variable.
(struct syscalls_info) <sysinfo>: Rename variable to
"syscalls_info".
(sysinfo): Delete global variable.
(have_initialized_sysinfo): Likewise.
(xml_syscall_file): Likewise.
(sysinfo_free_syscalls_desc): Rename to...
(syscalls_info_free_syscalls_desc): ... this.
(free_syscalls_info): Rename "sysinfo" to "syscalls_info". Adjust
code to the new layout of "struct syscalls_info".
(make_cleanup_free_syscalls_info): Rename parameter "sysinfo" to
"syscalls_info".
(syscall_create_syscall_desc): Likewise.
(syscall_start_syscall): Likewise.
(syscall_parse_xml): Likewise.
(xml_init_syscalls_info): Likewise. Drop "const" from return value.
(init_sysinfo): Rename to...
(init_syscalls_info): ...this. Add gdbarch as a parameter.
Adjust function to deal with gdbarch.
(xml_get_syscall_number): Delete parameter sysinfo. Accept
gdbarch as a parameter. Adjust code.
(xml_get_syscall_name): Likewise.
(xml_list_of_syscalls): Likewise.
(set_xml_syscall_file_name): Accept gdbarch as parameter.
(get_syscall_by_number): Likewise.
(get_syscall_by_name): Likewise.
(get_syscall_names): Likewise.
* xml-syscall.h (set_xml_syscall_file_name): Likewise.
(get_syscall_by_number): Likewise.
(get_syscall_by_name): Likewise.
(get_syscall_names): Likewise.
gdb/testsuite/
2014-11-20 Sergio Durigan Junior <sergiodj@redhat.com>
PR breakpoints/10737
* gdb.base/catch-syscall.exp (do_syscall_tests): Call
test_catch_syscall_multi_arch.
(test_catch_syscall_multi_arch): New function.
Currently "symtabs" in gdb are stored as a single linked list of
struct symtab that contains both symbol symtabs (the blockvectors)
and file symtabs (the linetables).
This has led to confusion, bugs, and performance issues.
This patch is conceptually very simple: split struct symtab into
two pieces: one part containing things common across the entire
compilation unit, and one part containing things specific to each
source file.
Example.
For the case of a program built out of these files:
foo.c
foo1.h
foo2.h
bar.c
foo1.h
bar.h
Today we have a single list of struct symtabs:
objfile -> foo.c -> foo1.h -> foo2.h -> bar.c -> foo1.h -> bar.h -> NULL
where "->" means the "next" pointer in struct symtab.
With this patch, that turns into:
objfile -> foo.c(cu) -> bar.c(cu) -> NULL
| |
v v
foo.c bar.c
| |
v v
foo1.h foo1.h
| |
v v
foo2.h bar.h
| |
v v
NULL NULL
where "foo.c(cu)" and "bar.c(cu)" are struct compunit_symtab objects,
and the files foo.c, etc. are struct symtab objects.
So now, for example, when we want to iterate over all blockvectors
we can now just iterate over the compunit_symtab list.
Plus a lot of the data that was either unused or replicated for each
symtab in a compilation unit now lives in struct compunit_symtab.
E.g., the objfile pointer, the producer string, etc.
I thought of moving "language" out of struct symtab but there is
logic to try to compute the language based on previously seen files,
and I think that's best left as is for now.
With my standard monster benchmark with -readnow (which I can't actually
do, but based on my calculations), whereas today the list requires
77MB to store all the struct symtabs, it now only requires 37MB.
A modest space savings given the gigabytes needed for all the debug info,
etc. Still, it's nice. Plus, whereas today we create a copy of dirname
for each source file symtab in a compilation unit, we now only create one
for the compunit.
So this patch is basically just a data structure reorg,
I don't expect significant performance improvements from it.
Notes:
1) A followup patch can do a similar split for struct partial_symtab.
I have left that until after I get the changes I want in to
better utilize .gdb_index (it may affect how we do partial syms).
2) Another followup patch *could* rename struct symtab.
The term "symtab" is ambiguous and has been a source of confusion.
In this patch I'm leaving it alone, calling it the "historical" name
of "filetabs", which is what they are now: just the file-name + line-table.
gdb/ChangeLog:
Split struct symtab into two: struct symtab and compunit_symtab.
* amd64-tdep.c (amd64_skip_xmm_prologue): Fetch producer from compunit.
* block.c (blockvector_for_pc_sect): Change "struct symtab *" argument
to "struct compunit_symtab *". All callers updated.
(set_block_compunit_symtab): Renamed from set_block_symtab. Change
"struct symtab *" argument to "struct compunit_symtab *".
All callers updated.
(get_block_compunit_symtab): Renamed from get_block_symtab. Change
result to "struct compunit_symtab *". All callers updated.
(find_iterator_compunit_symtab): Renamed from find_iterator_symtab.
Change result to "struct compunit_symtab *". All callers updated.
* block.h (struct global_block) <compunit_symtab>: Renamed from symtab.
hange type to "struct compunit_symtab *". All uses updated.
(struct block_iterator) <d.compunit_symtab>: Renamed from "d.symtab".
Change type to "struct compunit_symtab *". All uses updated.
* buildsym.c (struct buildsym_compunit): New struct.
(subfiles, buildsym_compdir, buildsym_objfile, main_subfile): Delete.
(buildsym_compunit): New static global.
(finish_block_internal): Update to fetch objfile from
buildsym_compunit.
(make_blockvector): Delete objfile argument.
(start_subfile): Rewrite to use buildsym_compunit. Don't initialize
debugformat, producer.
(start_buildsym_compunit): New function.
(free_buildsym_compunit): Renamed from free_subfiles_list.
All callers updated.
(patch_subfile_names): Rewrite to use buildsym_compunit.
(get_compunit_symtab): New function.
(get_macro_table): Delete argument comp_dir. All callers updated.
(start_symtab): Change result to "struct compunit_symtab *".
All callers updated. Create the subfile of the main source file.
(watch_main_source_file_lossage): Rewrite to use buildsym_compunit.
(reset_symtab_globals): Update.
(end_symtab_get_static_block): Update to use buildsym_compunit.
(end_symtab_without_blockvector): Rewrite.
(end_symtab_with_blockvector): Change result to
"struct compunit_symtab *". All callers updated.
Update to use buildsym_compunit. Don't set symtab->dirname,
instead set it in the compunit.
Explicitly make sure main symtab is first in its list.
Set debugformat, producer, blockvector, block_line_section, and
macrotable in the compunit.
(end_symtab_from_static_block): Change result to
"struct compunit_symtab *". All callers updated.
(end_symtab, end_expandable_symtab): Ditto.
(set_missing_symtab): Change symtab argument to
"struct compunit_symtab *". All callers updated.
(augment_type_symtab): Ditto.
(record_debugformat): Update to use buildsym_compunit.
(record_producer): Update to use buildsym_compunit.
* buildsym.h (struct subfile) <dirname>: Delete.
<producer, debugformat>: Delete.
<buildsym_compunit>: New member.
(get_compunit_symtab): Declare.
* dwarf2read.c (struct type_unit_group) <compunit_symtab>: Renamed
from primary_symtab. Change type to "struct compunit_symtab *".
All uses updated.
(dwarf2_start_symtab): Change result to "struct compunit_symtab *".
All callers updated.
(dwarf_decode_macros): Delete comp_dir argument. All callers updated.
(struct dwarf2_per_cu_quick_data) <compunit_symtab>: Renamed from
symtab. Change type to "struct compunit_symtab *". All uses updated.
(dw2_instantiate_symtab): Change result to "struct compunit_symtab *".
All callers updated.
(dw2_find_last_source_symtab): Ditto.
(dw2_lookup_symbol): Ditto.
(recursively_find_pc_sect_compunit_symtab): Renamed from
recursively_find_pc_sect_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(dw2_find_pc_sect_compunit_symtab): Renamed from
dw2_find_pc_sect_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(get_compunit_symtab): Renamed from get_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(recursively_compute_inclusions): Change type of immediate_parent
argument to "struct compunit_symtab *". All callers updated.
(compute_compunit_symtab_includes): Renamed from
compute_symtab_includes. All callers updated. Rewrite to compute
includes of compunit_symtabs and not symtabs.
(process_full_comp_unit): Update to work with struct compunit_symtab.
(process_full_type_unit): Ditto.
(dwarf_decode_lines_1): Delete argument comp_dir. All callers updated.
(dwarf_decode_lines): Remove special case handling of main subfile.
(macro_start_file): Delete argument comp_dir. All callers updated.
(dwarf_decode_macro_bytes): Ditto.
* guile/scm-block.c (bkscm_print_block_syms_progress_smob): Update to
use struct compunit_symtab.
* i386-tdep.c (i386_skip_prologue): Fetch producer from compunit.
* jit.c (finalize_symtab): Build compunit_symtab.
* jv-lang.c (get_java_class_symtab): Change result to
"struct compunit_symtab *". All callers updated.
* macroscope.c (sal_macro_scope): Fetch macro table from compunit.
* macrotab.c (struct macro_table) <compunit_symtab>: Renamed from
comp_dir. Change type to "struct compunit_symtab *".
All uses updated.
(new_macro_table): Change comp_dir argument to cust,
"struct compunit_symtab *". All callers updated.
* maint.c (struct cmd_stats) <nr_compunit_symtabs>: Renamed from
nr_primary_symtabs. All uses updated.
(count_symtabs_and_blocks): Update to handle compunits.
(report_command_stats): Update output, "primary symtabs" renamed to
"compunits".
* mdebugread.c (new_symtab): Change result to
"struct compunit_symtab *". All callers updated.
(parse_procedure): Change type of search_symtab argument to
"struct compunit_symtab *". All callers updated.
* objfiles.c (objfile_relocate1): Loop over blockvectors in a
separate loop.
* objfiles.h (struct objfile) <compunit_symtabs>: Renamed from
symtabs. Change type to "struct compunit_symtab *". All uses updated.
(ALL_OBJFILE_FILETABS): Renamed from ALL_OBJFILE_SYMTABS.
All uses updated.
(ALL_OBJFILE_COMPUNITS): Renamed from ALL_OBJFILE_PRIMARY_SYMTABS.
All uses updated.
(ALL_FILETABS): Renamed from ALL_SYMTABS. All uses updated.
(ALL_COMPUNITS): Renamed from ALL_PRIMARY_SYMTABS. All uses updated.
* psympriv.h (struct partial_symtab) <compunit_symtab>: Renamed from
symtab. Change type to "struct compunit_symtab *". All uses updated.
* psymtab.c (psymtab_to_symtab): Change result type to
"struct compunit_symtab *". All callers updated.
(find_pc_sect_compunit_symtab_from_partial): Renamed from
find_pc_sect_symtab_from_partial. Change result type to
"struct compunit_symtab *". All callers updated.
(lookup_symbol_aux_psymtabs): Change result type to
"struct compunit_symtab *". All callers updated.
(find_last_source_symtab_from_partial): Ditto.
* python/py-symtab.c (stpy_get_producer): Fetch producer from compunit.
* source.c (forget_cached_source_info_for_objfile): Fetch debugformat
and macro_table from compunit.
* symfile-debug.c (debug_qf_find_last_source_symtab): Change result
type to "struct compunit_symtab *". All callers updated.
(debug_qf_lookup_symbol): Ditto.
(debug_qf_find_pc_sect_compunit_symtab): Renamed from
debug_qf_find_pc_sect_symtab, change result type to
"struct compunit_symtab *". All callers updated.
* symfile.c (allocate_symtab): Delete objfile argument.
New argument cust.
(allocate_compunit_symtab): New function.
(add_compunit_symtab_to_objfile): New function.
* symfile.h (struct quick_symbol_functions) <lookup_symbol>:
Change result type to "struct compunit_symtab *". All uses updated.
<find_pc_sect_compunit_symtab>: Renamed from find_pc_sect_symtab.
Change result type to "struct compunit_symtab *". All uses updated.
* symmisc.c (print_objfile_statistics): Compute blockvector count in
separate loop.
(dump_symtab_1): Update test for primary source symtab.
(maintenance_info_symtabs): Update to handle compunit symtabs.
(maintenance_check_symtabs): Ditto.
* symtab.c (set_primary_symtab): Delete.
(compunit_primary_filetab): New function.
(compunit_language): New function.
(iterate_over_some_symtabs): Change type of arguments "first",
"after_last" to "struct compunit_symtab *". All callers updated.
Update to loop over symtabs in each compunit.
(error_in_psymtab_expansion): Rename symtab argument to cust,
and change type to "struct compunit_symtab *". All callers updated.
(find_pc_sect_compunit_symtab): Renamed from find_pc_sect_symtab.
Change result type to "struct compunit_symtab *". All callers updated.
(find_pc_compunit_symtab): Renamed from find_pc_symtab.
Change result type to "struct compunit_symtab *". All callers updated.
(find_pc_sect_line): Only loop over symtabs within selected compunit
instead of all symtabs in the objfile.
* symtab.h (struct symtab) <blockvector>: Moved to compunit_symtab.
<compunit_symtab> New member.
<block_line_section>: Moved to compunit_symtab.
<locations_valid>: Ditto.
<epilogue_unwind_valid>: Ditto.
<macro_table>: Ditto.
<dirname>: Ditto.
<debugformat>: Ditto.
<producer>: Ditto.
<objfile>: Ditto.
<call_site_htab>: Ditto.
<includes>: Ditto.
<user>: Ditto.
<primary>: Delete
(SYMTAB_COMPUNIT): New macro.
(SYMTAB_BLOCKVECTOR): Update definition.
(SYMTAB_OBJFILE): Update definition.
(SYMTAB_DIRNAME): Update definition.
(struct compunit_symtab): New type. Common members among all source
symtabs within a compilation unit moved here. All uses updated.
(COMPUNIT_OBJFILE): New macro.
(COMPUNIT_FILETABS): New macro.
(COMPUNIT_DEBUGFORMAT): New macro.
(COMPUNIT_PRODUCER): New macro.
(COMPUNIT_DIRNAME): New macro.
(COMPUNIT_BLOCKVECTOR): New macro.
(COMPUNIT_BLOCK_LINE_SECTION): New macro.
(COMPUNIT_LOCATIONS_VALID): New macro.
(COMPUNIT_EPILOGUE_UNWIND_VALID): New macro.
(COMPUNIT_CALL_SITE_HTAB): New macro.
(COMPUNIT_MACRO_TABLE): New macro.
(ALL_COMPUNIT_FILETABS): New macro.
(compunit_symtab_ptr): New typedef.
(DEF_VEC_P (compunit_symtab_ptr)): New vector type.
gdb/testsuite/ChangeLog:
* gdb.base/maint.exp: Update expected output.
"permanent"-ness is currently a property of the breakpoint. But, it
should actually be an implementation detail of a _location_. Consider
this bit in infrun.c:
/* Normally, by the time we reach `resume', the breakpoints are either
removed or inserted, as appropriate. The exception is if we're sitting
at a permanent breakpoint; we need to step over it, but permanent
breakpoints can't be removed. So we have to test for it here. */
if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
{
if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
else
error (_("\
The program is stopped at a permanent breakpoint, but GDB does not know\n\
how to step past a permanent breakpoint on this architecture. Try using\n\
a command like `return' or `jump' to continue execution."));
}
This will wrongly skip a non-breakpoint instruction if we have a
multiple location breakpoint where the whole breakpoint was set to
"permanent" because one of the locations happened to be permanent,
even if the one GDB is resuming from is not.
Related, because the permanent breakpoints are only marked as such in
init_breakpoint_sal, we currently miss marking momentary breakpoints
as permanent. A test added by a following patch trips on that.
Making permanent-ness be per-location, and marking locations as such
in add_location_to_breakpoint, the natural place to do this, fixes
this issue...
... and then exposes a latent issue with mark_breakpoints_out. It's
clearing the inserted flag of permanent breakpoints. This results in
assertions failing like this:
Breakpoint 1, main () at testsuite/gdb.base/callexit.c:32
32 return 0;
(gdb) call callexit()
[Inferior 1 (process 15849) exited normally]
gdb/breakpoint.c:12854: internal-error: allegedly permanent breakpoint is not actually inserted
A problem internal to GDB has been detected,
further debugging may prove unreliable.
The call dummy breakpoint, which is a momentary breakpoint, is set on
top of a manually inserted breakpoint instruction, and so is now
rightfully marked as a permanent breakpoint. See "Write a legitimate
instruction at the point where the infcall breakpoint is going to be
inserted." comment in infcall.c.
Re. make_breakpoint_permanent. That's only called by solib-pa64.c.
Permanent breakpoints were actually originally invented for HP-UX [1].
I believe that that call (the only one in the tree) is unnecessary
nowadays, given that nowadays the core breakpoints code analyzes the
instruction under the breakpoint to automatically detect whether it's
setting a breakpoint on top of a breakpoint instruction in the
program. I know close to nothing about HP-PA/HP-UX, though.
[1] https://sourceware.org/ml/gdb-patches/1999-q3/msg00245.html, and
https://sourceware.org/ml/gdb-patches/1999-q3/msg00242.html
In addition to the per-location issue, "permanent breakpoints" are
currently always displayed as enabled=='n':
(gdb) b main
Breakpoint 3 at 0x40053c: file ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S, line 29.
(gdb) info breakpoints
Num Type Disp Enb Address What
3 breakpoint keep n 0x000000000040053c ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S:29
But OTOH they're always enabled; there's no way to disable them...
In turn, this means that if one adds commands to such a breakpoint,
they're _always_ run:
(gdb) start
Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.arch/i386-permbkpt
...
Temporary breakpoint 1, main () at ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S:29
29 int3
(gdb) b main
Breakpoint 2 at 0x40053c: file ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S, line 29.
(gdb) info breakpoints
Num Type Disp Enb Address What
2 breakpoint keep n 0x000000000040053c ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S:29
(gdb) commands
Type commands for breakpoint(s) 2, one per line.
End with a line saying just "end".
>echo "hello!"
>end
(gdb) disable 2
(gdb) start
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Temporary breakpoint 3 at 0x40053c: file ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S, line 29.
Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.arch/i386-permbkpt
Breakpoint 2, main () at ../../../src/gdb/testsuite/gdb.arch/i386-permbkpt.S:29
29 int3
"hello!"(gdb)
IMO, one should be able to disable such a breakpoint, and GDB should
then behave just like if the user hadn't created the breakpoint in the
first place (that is, report a SIGTRAP).
By making permanent-ness a property of the location, and eliminating
the bp_permanent enum enable_state state ends up fixing that as well.
No tests are added for these changes yet; they'll be added in a follow
up patch, as skipping permanent breakpoints is currently broken and
trips on an assertion in infrun.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
2014-11-12 Pedro Alves <palves@redhat.com>
Mark locations as permanent, not the whole breakpoint.
* breakpoint.c (remove_breakpoint_1, remove_breakpoint): Adjust.
(mark_breakpoints_out): Don't mark permanent breakpoints as
uninserted.
(breakpoint_init_inferior): Use mark_breakpoints_out.
(breakpoint_here_p): Adjust.
(bpstat_stop_status, describe_other_breakpoints): Remove handling
of permanent breakpoints.
(make_breakpoint_permanent): Mark each location as permanent,
instead of marking the breakpoint.
(add_location_to_breakpoint): If the location is permanent, mark
it as such, and as inserted.
(init_breakpoint_sal): Don't make the breakpoint permanent here.
(bp_location_compare, update_global_location_list): Adjust.
(update_breakpoint_locations): Don't make the breakpoint permanent
here.
(disable_breakpoint, enable_breakpoint_disp): Don't skip permanent
breakpoints.
* breakpoint.h (enum enable_state) <bp_permanent>: Delete field.
(struct bp_location) <permanent>: New field.
* guile/scm-breakpoint.c (bpscm_enable_state_to_string): Remove
reference to bp_permanent.
Used to be necessary for the thread-hop code, but that's gone now.
Nothing uses this anymore.
gdb/
2014-11-04 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoint_thread_match): Delete function.
* breakpoint.h (breakpoint_thread_match): Delete declaration.
This patch finally makes each thread have its own set of single-step
breakpoints. This paves the way to have multiple threads software
single-stepping, though this patch doesn't flip that switch on yet.
That'll be done on a subsequent patch.
gdb/
2014-10-15 Pedro Alves <palves@redhat.com>
* breakpoint.c (single_step_breakpoints): Delete global.
(insert_single_step_breakpoint): Adjust to store the breakpoint
pointer in the current thread.
(single_step_breakpoints_inserted, remove_single_step_breakpoints)
(cancel_single_step_breakpoints): Delete functions.
(breakpoint_has_location_inserted_here): Make extern.
(single_step_breakpoint_inserted_here_p): Adjust to walk the
breakpoint list.
* breakpoint.h (breakpoint_has_location_inserted_here): New
declaration.
(single_step_breakpoints_inserted, remove_single_step_breakpoints)
(cancel_single_step_breakpoints): Remove declarations.
* gdbthread.h (struct thread_control_state)
<single_step_breakpoints>: New field.
(delete_single_step_breakpoints)
(thread_has_single_step_breakpoints_set)
(thread_has_single_step_breakpoint_here): New declarations.
* infrun.c (follow_exec): Also clear the single-step breakpoints.
(singlestep_breakpoints_inserted_p, singlestep_ptid)
(singlestep_pc): Delete globals.
(infrun_thread_ptid_changed): Remove references to removed
globals.
(resume_cleanups): Delete the current thread's single-step
breakpoints.
(maybe_software_singlestep): Remove references to removed globals.
(resume): Adjust to use thread_has_single_step_breakpoints_set and
delete_single_step_breakpoints.
(init_wait_for_inferior): Remove references to removed globals.
(delete_thread_infrun_breakpoints): Delete the thread's
single-step breakpoints too.
(delete_just_stopped_threads_infrun_breakpoints): Don't delete
single-step breakpoints here.
(delete_stopped_threads_single_step_breakpoints): New function.
(adjust_pc_after_break): Adjust to use
thread_has_single_step_breakpoints_set.
(handle_inferior_event): Remove references to removed globals.
Use delete_stopped_threads_single_step_breakpoints.
(handle_signal_stop): Adjust to per-thread single-step
breakpoints. Swap test order to do cheaper tests first.
(switch_back_to_stepped_thread): Extend debug output. Remove
references to removed globals.
* record-full.c (record_full_wait_1): Adjust to per-thread
single-step breakpoints.
* thread.c (delete_single_step_breakpoints)
(thread_has_single_step_breakpoints_set)
(thread_has_single_step_breakpoint_here): New functions.
(clear_thread_inferior_resources): Also delete the thread's
single-step breakpoints.
There are no users of deprecated_{insert,remove}_raw_breakpoint left.
gdb/
2014-10-15 Pedro Alves <palves@redhat.com>
* breakpoint.c (regular_breakpoint_inserted_here_p): Inline ...
(breakpoint_inserted_here_p): ... here. Remove special case for
software single-step breakpoints.
(find_non_raw_software_breakpoint_inserted_here): Inline ...
(software_breakpoint_inserted_here_p): ... here. Remove special
case for software single-step breakpoints.
(bp_target_info_copy_insertion_state)
(deprecated_insert_raw_breakpoint)
(deprecated_remove_raw_breakpoint): Delete functions.
* breakpoint.h (deprecated_insert_raw_breakpoint)
(deprecated_remove_raw_breakpoint): Remove declarations.
This patch makes single-step breakpoints "real" breakpoints on the
global location list.
There are several benefits to this:
- It removes the currently limitation that only 2 single-step
breakpoints can be inserted. See an example here of a discussion
around a case that wants more than 2, possibly unbounded:
https://sourceware.org/ml/gdb-patches/2014-03/msg00663.html
- makes software single-step work on read-only code regions.
The logic to convert a software breakpoint to a hardware breakpoint
if the memory map says the breakpoint address is in read only memory
is in insert_bp_location. Because software single-step breakpoints
bypass all that go and straight to target_insert_breakpoint, we
can't software single-step over read only memory. This patch
removes that limitation, and adds a test that makes sure that works,
by forcing a code region to read-only with "mem LOW HIGH ro" and
then stepping through that.
- Fixes PR breakpoints/9649
This is an assertion failure in insert_single_step_breakpoint in
breakpoint.c, because we may leave stale single-step breakpoints
behind on error.
The tests for stepping through read-only regions exercise the root
cause of the bug, which is that we leave single-step breakpoints
behind if we fail to insert any single-step breakpoint. Deleting
the single-step breakpoints in resume_cleanups,
delete_just_stopped_threads_infrun_breakpoints, and
fetch_inferior_event fixes this. Without that, we'd no longer hit
the assertion, as that code is deleted, but we'd instead run into
errors/warnings trying to insert/remove the stale breakpoints on
next resume.
- Paves the way to have multiple threads software single-stepping at
the same time, leaving update_global_location_list to worry about
duplicate locations.
- Makes the moribund location machinery aware of software single-step
breakpoints, paving the way to enable software single-step on
non-stop, instead of forcing serialized displaced stepping for all
single steps.
- It's generaly cleaner.
We no longer have to play games with single-step breakpoints
inserted at the same address as regular breakpoints, like we
recently had to do for 7.8. See this discussion:
https://sourceware.org/ml/gdb-patches/2014-06/msg00052.html.
Tested on x86_64 Fedora 20, on top of my 'single-step breakpoints on
x86' series.
gdb/
2014-10-15 Pedro Alves <palves@redhat.com>
PR breakpoints/9649
* breakpoint.c (single_step_breakpoints, single_step_gdbarch):
Delete array globals.
(single_step_breakpoints): New global.
(breakpoint_xfer_memory): Remove special handling for single-step
breakpoints.
(update_breakpoints_after_exec): Delete bp_single_step
breakpoints.
(detach_breakpoints): Remove special handling for single-step
breakpoints.
(breakpoint_init_inferior): Delete bp_single_step breakpoints.
(bpstat_stop_status): Add comment.
(bpstat_what, bptype_string, print_one_breakpoint_location)
(adjust_breakpoint_address, init_bp_location): Handle
bp_single_step.
(new_single_step_breakpoint): New function.
(set_momentary_breakpoint, bkpt_remove_location): Remove special
handling for single-step breakpoints.
(insert_single_step_breakpoint, single_step_breakpoints_inserted)
(remove_single_step_breakpoints, cancel_single_step_breakpoints):
Rewrite.
(detach_single_step_breakpoints, find_single_step_breakpoint):
Delete functions.
(breakpoint_has_location_inserted_here): New function.
(single_step_breakpoint_inserted_here_p): Rewrite.
* breakpoint.h: Remove FIXME.
(enum bptype) <bp_single_step>: New enum value.
(insert_single_step_breakpoint): Update comment.
* infrun.c (resume_cleanups)
(delete_step_thread_step_resume_breakpoint): Remove single-step
breakpoints.
(fetch_inferior_event): Install a cleanup that removes infrun
breakpoints.
(switch_back_to_stepped_thread) <expect thread advanced also>:
Clear step-over info.
gdb/testsuite/
2014-10-15 Pedro Alves <palves@redhat.com>
PR breakpoints/9649
* gdb.base/breakpoint-in-ro-region.c (main): Add more instructions.
* gdb.base/breakpoint-in-ro-region.exp
(probe_target_hardware_step): New procedure.
(top level): Probe hardware stepping and hardware breakpoint
support. Test stepping through a read-only region, with both
"breakpoint auto-hw" on and off and both "always-inserted" on and
off.
When GDB finds out the target triggered a watchpoint, and the target
has non-continuable watchpoints, GDB sets things up to step past the
instruction that triggered the watchpoint. This is just like stepping
past a breakpoint, but goes through a different mechanism - it resumes
only the thread that needs to step past the watchpoint, but also
switches a "infwait state" global, that has the effect that the next
target_wait only wait for events only from that thread.
This forcing of a ptid to pass to target_wait obviously becomes a
bottleneck if we ever support stepping past different watchpoints
simultaneously (in separate processes).
It's also unnecessary -- the target should only return events for
threads that have been resumed; if no other thread than the one we're
stepping past the watchpoint has been resumed, then those other
threads should not report events. If we couldn't assume that, then
stepping past regular breakpoints would be broken for not likewise
forcing a similar infwait_state.
So this patch eliminates infwait_state, and instead teaches keep_going
to mark step_over_info in a way that has the breakpoints module skip
inserting watchpoints (because we're stepping past one), like it skips
breakpoints when we're stepping past one.
Tested on:
- x86_64 Fedora 20 (continuable watchpoints)
- PPC64 Fedora 18 (non-steppable watchpoints)
gdb/
2014-10-15 Pedro Alves <palves@redhat.com>
* breakpoint.c (should_be_inserted): Don't insert watchpoints if
trying to step past a non-steppable watchpoint.
* gdbthread.h (struct thread_info) <stepping_over_watchpoint>: New
field.
* infrun.c (struct step_over_info): Add new field
'nonsteppable_watchpoint_p' and adjust comments.
(set_step_over_info): New 'nonsteppable_watchpoint_p' parameter.
Adjust.
(clear_step_over_info): Clear nonsteppable_watchpoint_p as well.
(stepping_past_nonsteppable_watchpoint): New function.
(step_over_info_valid_p): Also return true if stepping past a
nonsteppable watchpoint.
(proceed): Adjust call to set_step_over_info. Remove reference to
init_infwait_state.
(init_wait_for_inferior): Remove reference to init_infwait_state.
(waiton_ptid): Delete global.
(struct execution_control_state)
<stepped_after_stopped_by_watchpoint>: Delete field.
(wait_for_inferior, fetch_inferior_event): Always pass
minus_one_ptid to target_wait.
(init_thread_stepping_state): Clear 'stepping_over_watchpoint'
field.
(init_infwait_state): Delete function.
(handle_inferior_event): Remove infwait_state handling.
(handle_signal_stop) <watchpoints handling>: Adjust after
stepped_after_stopped_by_watchpoint removal. Don't remove
breakpoints here nor set infwait_state. Set the thread's
stepping_over_watchpoint flag, and call keep_going instead.
(keep_going): Handle stepping_over_watchpoint. Adjust
set_step_over_info calls.
* infrun.h (stepping_past_nonsteppable_watchpoint): Declare
function.
This patch is a response to what I commented on:
<https://sourceware.org/ml/gdb-patches/2014-10/msg00046.html>
When reviewing Jose's USDT probe support patches. Basically, in his
patch he had to create dummy functions for the set_semaphore and the
clear_semaphore methods of probe_ops (gdb/probe.h), because those
functions were called inconditionally from inside gdb/breakpoint.c and
gdb/tracepoint.c. However, the semaphore concept may not apply to all
types of probes, and this is the case here: USDT probes do not have
semaphores (although SDT probes do).
Anyway, this is a simple (almost obvious) patch to guard the call to
{set,clear}_semaphore. It does not introduce any regression on a
Fedora 20 x86_64.
I will apply it in a few days in case there is no comment.
gdb/ChangeLog:
2014-10-14 Sergio Durigan Junior <sergiodj@redhat.com>
* breakpoint.c (bkpt_probe_insert_location): Call set_semaphore
only if it is not NULL.
(bkpt_probe_remove_location): Likewise, for clear_semaphore.
* probe.h (struct probe_ops) <set_semaphore>: Update comment.
(struct probe_ops) <clear_semaphore>: Likewise.
* tracepoint.c (start_tracing): Call set_semaphore only if it is
not NULL.
(stop_tracing): Likewise, for clear_semaphore.
This change:
commit b775012e84
Author: Luis Machado <luisgpm@br.ibm.com>
Date: Fri Feb 24 15:10:59 2012 +0000
2012-02-24 Luis Machado <lgustavo@codesourcery.com>
* remote.c (remote_supports_cond_breakpoints): New forward
declaration.
[...]
changed the way breakpoints are inserted and removed such that
`insert_bp_location' can now be called with the breakpoint being handled
already in place, while previously the call was only ever made for
breakpoints that have not been put in place. This in turn caused an
issue for software breakpoints and targets for which a breakpoint's
`placed_address' may not be the same as the original requested address.
The issue is `insert_bp_location' overwrites the previously adjusted
value in `placed_address' with the original address, that is only
replaced back with the correct adjusted address later on when
`gdbarch_breakpoint_from_pc' is called. Meanwhile there's a window
where the value in `placed_address' does not correspond to data stored
in `shadow_contents', leading to incorrect instruction bytes being
supplied when `one_breakpoint_xfer_memory' is called to supply the
instruction overlaid by the breakpoint.
And this is exactly what happens on the MIPS target with software
breakpoints placed in microMIPS code. In this case not only
`placed_address' is not the original address because of the ISA bit, but
`mips_breakpoint_from_pc' has to read the original instruction to
determine which one of the two software breakpoint instruction encodings
to choose as well. The 16-bit encoding is used to replace 16-bit
instructions and similarly the 32-bit one is used with 32-bit
instructions, to satisfy branch delay slot size requirements.
The mismatch between `placed_address' and the address data in
`shadow_contents' has been obtained from leads to the wrong encoding
being used in some cases, which in the case of a 32-bit software
breakpoint instruction replacing a 16-bit instruction causes corruption
to the adjacent following instruction and leads the debug session astray
if execution reaches there e.g. with a jump.
To address this problem I made the change below, that adds a
`reqstd_address' field to `struct bp_target_info' and leaves
`placed_address' unchanged once it has been set. This ensures data in
`shadow_contents' is always consistent with `placed_address'.
This approach also has this good side effect that all the places that
examine the breakpoint's address see a consistent value, either
`reqstd_address' or `placed_address', as required. Currently some
places see either the original or the adjusted address in
`placed_address', depending on whether they have been called before
`gdbarch_remote_breakpoint_from_pc' or afterwards. This is in
particular true for subsequent calls to
`gdbarch_remote_breakpoint_from_pc' itself, e.g. from
`one_breakpoint_xfer_memory'. This is also important for places like
`find_single_step_breakpoint' where a breakpoint's address is compared
to the raw value of $pc.
* breakpoint.h (bp_target_info): Add `reqstd_address' member,
update comments.
* breakpoint.c (one_breakpoint_xfer_memory): Use `reqstd_address'
for the breakpoint's address. Don't preinitialize `placed_size'.
(insert_bp_location): Set `reqstd_address' rather than
`placed_address'.
(bp_target_info_copy_insertion_state): Also copy `placed_address'.
(bkpt_insert_location): Use `reqstd_address' for the breakpoint's
address.
(bkpt_remove_location): Likewise.
(deprecated_insert_raw_breakpoint): Likewise.
(deprecated_remove_raw_breakpoint): Likewise.
(find_single_step_breakpoint): Likewise.
* mem-break.c (default_memory_insert_breakpoint): Use
`reqstd_address' for the breakpoint's address. Don't set
`placed_address' or `placed_size' if breakpoint contents couldn't
have been determined.
* remote.c (remote_insert_breakpoint): Use `reqstd_address' for
the breakpoint's address.
(remote_insert_hw_breakpoint): Likewise. Don't set
`placed_address' or `placed_size' if breakpoint couldn't have been
set.
* aarch64-linux-nat.c (aarch64_linux_insert_hw_breakpoint): Use
`reqstd_address' for the breakpoint's address.
* arm-linux-nat.c (arm_linux_hw_breakpoint_initialize): Likewise.
* ia64-tdep.c (ia64_memory_insert_breakpoint): Likewise.
* m32r-tdep.c (m32r_memory_insert_breakpoint): Likewise.
* microblaze-linux-tdep.c
(microblaze_linux_memory_remove_breakpoint): Likewise.
* monitor.c (monitor_insert_breakpoint): Likewise.
* nto-procfs.c (procfs_insert_breakpoint): Likewise.
(procfs_insert_hw_breakpoint): Likewise.
* ppc-linux-nat.c (ppc_linux_insert_hw_breakpoint): Likewise.
* ppc-linux-tdep.c (ppc_linux_memory_remove_breakpoint): Likewise.
* remote-m32r-sdi.c (m32r_insert_breakpoint): Likewise.
* remote-mips.c (mips_insert_breakpoint): Likewise.
* x86-nat.c (x86_insert_hw_breakpoint): Likewise.
Commit a25a5a45 (Fix "breakpoint always-inserted off"; remove
"breakpoint always-inserted auto") regressed non-stop remote
debugging.
This was exposed by mi-nsintrall.exp intermittently failing with a
spurious SIGTRAP.
The problem is that when debugging with "target remote", new threads
the target has spawned but have never reported a stop aren't visible
to GDB until it explicitly resyncs its thread list with the target's.
For example, in a program like this:
int
main (void)
{
pthread_t child_thread;
pthread_create (&child_thread, NULL, child_function, NULL);
return 0; <<<< set breakpoint here
}
If the user sets a breakpoint at the "return" statement, and runs the
program, when that breakpoint hit is reported, GDB is only aware of
the main thread. So if we base the decision to remove or insert
breakpoints from the target based on whether all the threads we know
about are stopped, we'll miss that child_thread is running, and thus
we'll remove breakpoints from the target, even through they should
still remain inserted, otherwise child_thread will miss them.
The break-while-running.exp test actually should also be exposing this
thread-list-out-of-synch problem. That test sets a breakpoint while
the main thread is stopped, but other threads are running. Because
other threads are running, the breakpoint is supposed to be inserted
immediately. But, unless something forces a refetch of the thread
list, like, e.g., "info threads", GDB won't be aware of the other
threads that had been spawned by the main thread, and so won't insert
new or old breakpoints in the target. And it turns out that the test
is exactly doing an explicit "info threads", masking out the
problem... This commit adjust the test to exercise the case of not
issuing "info threads". The test then fails without the GDB fix.
In the ni-nsintrall.exp case, what happens is that several threads hit
the same breakpoint, and when the first thread reports the stop,
because GDB wasn't aware other threads exist, all threads known to GDB
are found stopped, so GDB removes the breakpoints from the target.
The other threads follow up with SIGTRAPs too for that same
breakpoint, which has already been removed. For the first few
threads, the moribund breakpoints machinery suppresses the SIGTRAPs,
but after a few events (precisely '3 * thread_count () + 1' at the
time the breakpoint was removed, see update_global_location_list), the
moribund breakpoint machinery is no longer aware of the removed
breakpoint, and the SIGTRAP is reported as a spurious stop.
The fix is naturally then to stop assuming that if no thread in the
list is executing, then the target is fully stopped. We can't know
that until we fully sync the thread list. Because updating the thread
list on every stop would be too much RSP traffic, I chose instead to
update it whenever we're about to present a stop to the user.
Actually updating the thread list at that point happens to be an item
I had added to the local/remote parity wiki page a while ago:
Native GNU/Linux debugging adds new threads to the thread list as
the program creates them "The [New Thread foo] messages". Remote
debugging can't do that, and it's arguable whether we shouldn't even
stop native debugging from doing that, as it hinders inferior
performance. However, a related issue is that with remote targets
(and gdbserver), even after the program stops, the user still needs
to do "info threads" to pull an updated thread list. This, should
most likely be addressed, so that GDB pulls the list itself, perhaps
just before presenting a stop to the user.
With that in place, the need to delay "Program received signal FOO"
was actually caught by the manythreads.exp test. Without that bit, I
was getting:
[Thread 0x7ffff7f13700 (LWP 4499) exited]
[New Thread 0x7ffff7f0b700 (LWP 4500)]
^C
Program received signal SIGINT, Interrupt.
[New Thread 0x7ffff7f03700 (LWP 4501)] <<< new output
[Switching to Thread 0x7ffff7f0b700 (LWP 4500)]
__GI___nptl_death_event () at events.c:31
31 {
(gdb) FAIL: gdb.threads/manythreads.exp: stop threads 1
That is, I was now getting "New Thread" lines after the "Program
received signal" line, and the test doesn't expect them. As the
number of new threads discovered before and after the "Program
received signal" output is unbounded, it's much nicer to defer
"Program received signal" until after synching the thread list, thus
close to the "switching to thread" output and "current frame/source"
info:
[Thread 0x7ffff7863700 (LWP 7647) exited]
^C[New Thread 0x7ffff786b700 (LWP 7648)]
Program received signal SIGINT, Interrupt.
[Switching to Thread 0x7ffff7fc4740 (LWP 6243)]
__GI___nptl_create_event () at events.c:25
25 {
(gdb) PASS: gdb.threads/manythreads.exp: stop threads 1
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoints_should_be_inserted_now): Use
threads_are_executing.
* breakpoint.h (breakpoints_should_be_inserted_now): Add
describing comment.
* gdbthread.h (threads_are_executing): Declare.
(handle_signal_stop) <random signals>: Don't print about the
signal here if stopping.
(end_stepping_range): Don't notify observers here.
(normal_stop): Update the thread list. If stopped by a random
signal or a stepping range ended, notify observers.
* thread.c (threads_executing): New global.
(init_thread_list): Clear 'threads_executing'.
(set_executing): Set or clear 'threads_executing'.
(threads_are_executing): New function.
(update_threads_executing): New function.
(update_thread_list): Use it.
gdb/testsuite/
2014-10-02 Pedro Alves <palves@redhat.com>
* gdb.threads/break-while-running.exp (test): Add new
'update_thread_list' argument. Skip "info threads" if false.
(top level): Add new 'update_thread_list' axis.
Following an exec with "breakpoint always-inserted on" tries to insert
breakpoints in the new image at the addresses the symbols had in the
old image.
With "always-inserted off", we see:
gdb gdb.multi/multi-arch-exec -ex "set breakpoint always-inserted off"
GNU gdb (GDB) 7.8.50.20140924-cvs
...
(gdb) b main
Breakpoint 1 at 0x400664: file gdb.multi/multi-arch-exec.c, line 24.
^^^^^^^^
(gdb) c
The program is not being run.
(gdb) r
Starting program: testsuite/gdb.multi/multi-arch-exec
Breakpoint 1, main () at gdb/testsuite/gdb.multi/multi-arch-exec.c:24
24 execl (BASEDIR "/multi-arch-exec-hello",
(gdb) c
Continuing.
process 9212 is executing new program: gdb/testsuite/gdb.multi/multi-arch-exec-hello
Breakpoint 1, main () at gdb/testsuite/gdb.multi/hello.c:40
40 bar();
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y 0x080484e4 in main at gdb/testsuite/gdb.multi/hello.c:40
^^^^^^^^^^
breakpoint already hit 2 times
(gdb)
Note how main was 0x400664 in multi-arch-exec, and 0x080484e4 in
gdb.multi/hello.
With "always-inserted on", we get:
Breakpoint 1, main () at gdb/testsuite/gdb.multi/multi-arch-exec.c:24
24 execl (BASEDIR "/multi-arch-exec-hello",
(gdb) c
Continuing.
infrun: target_wait (-1, status) =
infrun: 9444 [process 9444],
infrun: status->kind = execd
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_EXECD
Warning:
Cannot insert breakpoint 1.
Cannot access memory at address 0x400664
(gdb)
That is, GDB is trying to insert a breakpoint at 0x400664, after the
exec, and then that address happens to not be mapped at all in the new
image.
The problem is that update_breakpoints_after_exec is creating
breakpoints, which ends up in update_global_location_list immediately
inserting breakpoints if "breakpoints always-inserted" is "on".
update_breakpoints_after_exec is called very early when we see an exec
event. At that point, we haven't loaded the symbols of the new
post-exec image yet, and thus haven't reset breakpoint's addresses to
whatever they may be in the new image. All we should be doing in
update_breakpoints_after_exec is deleting breakpoints that no longer
make sense after an exec. So the fix removes those breakpoint
creations.
The question is then, if not here, where are those breakpoints
re-created? Turns out we don't need to do anything else, because at
the end of follow_exec, we call breakpoint_re_set, whose tail is also
creating exactly the same breakpoints update_breakpoints_after_exec is
currently creating:
breakpoint_re_set (void)
{
...
create_overlay_event_breakpoint ();
create_longjmp_master_breakpoint ();
create_std_terminate_master_breakpoint ();
create_exception_master_breakpoint ();
}
A new test is added to exercise this.
Tested on x86_64 Fedora 20.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
PR breakpoints/17431
* breakpoint.c (update_breakpoints_after_exec): Don't create
overlay, longjmp, std terminate nor exception breakpoints here.
gdb/testsuite/
2014-10-02 Pedro Alves <palves@redhat.com>
PR breakpoints/17431
* gdb.base/execl-update-breakpoints.c: New file.
* gdb.base/execl-update-breakpoints.exp: New file.
Currently, with "set breakpoint auto-hw off", we'll still try to
insert a software breakpoint at addresses covered by supposedly
read-only or inacessible regions:
(top-gdb) mem 0x443000 0x450000 ro
(top-gdb) set mem inaccessible-by-default off
(top-gdb) disassemble
Dump of assembler code for function main:
0x0000000000443956 <+34>: movq $0x0,0x10(%rax)
=> 0x000000000044395e <+42>: movq $0x0,0x18(%rax)
0x0000000000443966 <+50>: mov -0x24(%rbp),%eax
0x0000000000443969 <+53>: mov %eax,-0x20(%rbp)
End of assembler dump.
(top-gdb) b *0x0000000000443969
Breakpoint 5 at 0x443969: file ../../src/gdb/gdb.c, line 29.
(top-gdb) c
Continuing.
warning: cannot set software breakpoint at readonly address 0x443969
Breakpoint 5, 0x0000000000443969 in main (argc=1, argv=0x7fffffffd918) at ../../src/gdb/gdb.c:29
29 args.argc = argc;
(top-gdb)
We warn, saying that the insertion can't be done, but then proceed
attempting the insertion anyway, and in case of manually added
regions, the insert actually succeeds.
This is a regression; GDB used to fail inserting the breakpoint. More
below.
I stumbled on this as I wrote a test that manually sets up a read-only
memory region with the "mem" command, in order to test GDB's behavior
with breakpoints set on read-only regions, even when the real memory
the breakpoints are set at isn't really read-only. I wanted that in
order to add a test that exercises software single-stepping through
read-only regions.
Note that the memory regions that target_memory_map returns aren't
like e.g., what would expect to see in /proc/PID/maps on Linux.
Instead, they're the physical memory map from the _debuggers_
perspective. E.g., a read-only region would be real ROM or flash
memory, while a read-only+execute mapping in /proc/PID/maps is still
read-write to the debugger (otherwise the debugger wouldn't be able to
set software breakpoints in the code segment).
If one tries to manually write to memory that falls within a memory
region that is known to be read-only, with e.g., "p foo = 1", then we
hit a check in memory_xfer_partial_1 before the write mananges to make
it to the target side.
But writing a software/memory breakpoint nowadays goes through
target_write_raw_memory, and unlike when writing memory with
TARGET_OBJECT_MEMORY, nothing on the TARGET_OBJECT_RAW_MEMORY path
checks whether we're trying to write to a read-only region.
At the time "breakpoint auto-hw" was added, we didn't have the
TARGET_OBJECT_MEMORY vs TARGET_OBJECT_RAW_MEMORY target object
distinction yet, and the code path in memory_xfer_partial that blocks
writes to read-only memory was hit for memory breakpoints too. With
GDB 6.8 we had:
warning: cannot set software breakpoint at readonly address 0000000000443943
Warning:
Cannot insert breakpoint 1.
Error accessing memory address 0x443943: Input/output error.
So I started out by fixing this by adding the memory region validation
to TARGET_OBJECT_RAW_MEMORY too.
But later, when testing against GDBserver, I realized that that would
only block software/memory breakpoints GDB itself inserts with
gdb/mem-break.c. If a target has a to_insert_breakpoint method, the
insertion request will still pass through to the target. So I ended
up converting the "cannot set breakpoint" warning in breakpoint.c to a
real error return, thus blocking the insertion sooner.
With that, we'll end up no longer needing the TARGET_OBJECT_RAW_MEMORY
changes once software single-step breakpoints are converted to real
breakpoints. We need them today as software single-step breakpoints
bypass insert_bp_location. But, it'll be best to leave that in as
safeguard anyway, for other direct uses of TARGET_OBJECT_RAW_MEMORY.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Error out if inserting a
software breakpoint at a read-only address.
* target.c (memory_xfer_check_region): New function, factored out
from ...
(memory_xfer_partial_1): ... this. Make the 'reg_len' local a
ULONGEST.
(target_xfer_partial) <TARGET_OBJECT_RAW_MEMORY>: Check the access
against the memory region attributes.
gdb/testsuite/
2014-10-01 Pedro Alves <palves@redhat.com>
* gdb.base/breakpoint-in-ro-region.c: New file.
* gdb.base/breakpoint-in-ro-region.exp: New file.
By default, GDB removes all breakpoints from the target when the
target stops and the prompt is given back to the user. This is useful
in case GDB crashes while the user is interacting, as otherwise,
there's a higher chance breakpoints would be left planted on the
target.
But, as long as any thread is running free, we need to make sure to
keep breakpoints inserted, lest a thread misses a breakpoint. With
that in mind, in preparation for non-stop mode, we added a "breakpoint
always-inserted on" mode. This traded off the extra crash protection
for never having threads miss breakpoints, and in addition is more
efficient if there's a ton of breakpoints to remove/insert at each
user command (e.g., at each "step").
When we added non-stop mode, and for a period, we required users to
manually set "always-inserted on" when they enabled non-stop mode, as
otherwise GDB removes all breakpoints from the target as soon as any
thread stops, which means the other threads still running will miss
breakpoints. The test added by this patch exercises this.
That soon revealed a nuisance, and so later we added an extra
"breakpoint always-inserted auto" mode, that made GDB behave like
"always-inserted on" when non-stop was enabled, and "always-inserted
off" when non-stop was disabled. "auto" was made the default at the
same time.
In hindsight, this "auto" setting was unnecessary, and not the ideal
solution. Non-stop mode does depends on breakpoints always-inserted
mode, but only as long as any thread is running. If no thread is
running, no breakpoint can be missed. The same is true for all-stop
too. E.g., if, in all-stop mode, and the user does:
(gdb) c&
(gdb) b foo
That breakpoint at "foo" should be inserted immediately, but it
currently isn't -- currently it'll end up inserted only if the target
happens to trip on some event, and is re-resumed, e.g., an internal
breakpoint triggers that doesn't cause a user-visible stop, and so we
end up in keep_going calling insert_breakpoints. The test added by
this patch also covers this.
IOW, no matter whether in non-stop or all-stop, if the target fully
stops, we can remove breakpoints. And no matter whether in all-stop
or non-stop, if any thread is running in the target, then we need
breakpoints to be immediately inserted. And then, if the target has
global breakpoints, we need to keep breakpoints even when the target
is stopped.
So with that in mind, and aiming at reducing all-stop vs non-stop
differences for all-stop-on-stop-of-non-stop, this patch fixes
"breakpoint always-inserted off" to not remove breakpoints from the
target until it fully stops, and then removes the "auto" setting as
unnecessary. I propose removing it straight away rather than keeping
it as an alias, unless someone complains they have scripts that need
it and that can't adjust.
Tested on x86_64 Fedora 20.
gdb/
2014-09-22 Pedro Alves <palves@redhat.com>
* NEWS: Mention merge of "breakpoint always-inserted" modes "off"
and "auto" merged.
* breakpoint.c (enum ugll_insert_mode): New enum.
(always_inserted_mode): Now a plain boolean.
(show_always_inserted_mode): No longer handle AUTO_BOOLEAN_AUTO.
(breakpoints_always_inserted_mode): Delete.
(breakpoints_should_be_inserted_now): New function.
(insert_breakpoints): Pass UGLL_INSERT to
update_global_location_list instead of calling
insert_breakpoint_locations manually.
(create_solib_event_breakpoint_1): New, factored out from ...
(create_solib_event_breakpoint): ... this.
(create_and_insert_solib_event_breakpoint): Use
create_solib_event_breakpoint_1 instead of calling
insert_breakpoint_locations manually.
(update_global_location_list): Change parameter type from boolean
to enum ugll_insert_mode. All callers adjusted. Adjust to use
breakpoints_should_be_inserted_now and handle UGLL_INSERT.
(update_global_location_list_nothrow): Change parameter type from
boolean to enum ugll_insert_mode.
(_initialize_breakpoint): "breakpoint always-inserted" option is
now a boolean command. Update help text.
* breakpoint.h (breakpoints_always_inserted_mode): Delete declaration.
(breakpoints_should_be_inserted_now): New declaration.
* infrun.c (handle_inferior_event) <TARGET_WAITKIND_LOADED>:
Remove breakpoints_always_inserted_mode check.
(normal_stop): Adjust to use breakpoints_should_be_inserted_now.
* remote.c (remote_start_remote): Likewise.
gdb/doc/
2014-09-22 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Set Breaks): Document that "set breakpoint
always-inserted off" is the default mode now. Delete
documentation of "set breakpoint always-inserted auto".
gdb/testsuite/
2014-09-22 Pedro Alves <palves@redhat.com>
* gdb.threads/break-while-running.exp: New file.
* gdb.threads/break-while-running.c: New file.
This adds a new mode for update_global_location_list, that allows
callers saying "please insert breakpoints, even if
breakpoints_always_inserted_mode() is false". This allows removing a
couple breakpoints_always_inserted_mode checks.
gdb/
2014-09-22 Pedro Alves <palves@redhat.com>
* breakpoint.c (enum ugll_insert_mode): Add UGLL_INSERT.
(insert_breakpoints): Don't call insert_breakpoint_locations here.
Instead, pass UGLL_INSERT to update_global_location_list.
(update_global_location_list): Change parameter type from boolean
to enum ugll_insert_mode. All callers adjusted. Adjust to use
breakpoints_should_be_inserted_now and handle UGLL_INSERT.
(create_solib_event_breakpoint_1): New, factored out from ...
(create_solib_event_breakpoint): ... this.
(create_and_insert_solib_event_breakpoint): Use
create_solib_event_breakpoint_1 instead of calling
insert_breakpoint_locations manually.
(update_global_location_list): Handle UGLL_INSERT.
Later we'll want a tristate, but for now, convert to an enum that maps 1-1
with the current boolean's true/false.
gdb/
2014-09-22 Pedro Alves <palves@redhat.com>
* breakpoint.c (enum ugll_insert_mode): New enum.
(update_global_location_list)
(update_global_location_list_nothrow): Change parameter type from
boolean to enum ugll_insert_mode. All callers adjusted.
PR 12526 reports that -location watchpoints against bitfield arguments
trigger false positives when bits around the bitfield, but not the
bitfield itself, are modified.
This happens because -location watchpoints naturally operate at the
byte level, not at the bit level. When the address of a bitfield
lvalue is taken, information about the bitfield (i.e. its offset and
size) is lost in the process.
This information must first be retained throughout the lifetime of the
-location watchpoint. This patch achieves this by adding two new
fields to the watchpoint struct: val_bitpos and val_bitsize. These
fields are set when a watchpoint is first defined in watch_command_1.
They are both equal to zero if the watchpoint is not a -location
watchpoint or if the argument is not a bitfield.
Then these bitfield parameters are used inside update_watchpoint and
watchpoint_check to extract the actual value of the bitfield from the
watchpoint address, with the help of a local helper function
extract_bitfield_from_watchpoint_value.
Finally when creating a HW breakpoint pointing to a bitfield, we
optimize the address and length of the breakpoint. By skipping over
the bytes that don't cover the bitfield, this step reduces the
frequency at which a read watchpoint for the bitfield is triggered.
It also reduces the number of times a false-positive call to
check_watchpoint is triggered for a write watchpoint.
gdb/
PR breakpoints/12526
* breakpoint.h (struct watchpoint): New fields val_bitpos and
val_bitsize.
* breakpoint.c (watch_command_1): Use these fields to retain
bitfield information.
(extract_bitfield_from_watchpoint_value): New function.
(watchpoint_check): Use it.
(update_watchpoint): Use it. Optimize the address and length of a
HW watchpoint pointing to a bitfield.
* value.h (unpack_value_bitfield): New prototype.
* value.c (unpack_value_bitfield): Make extern.
gdb/testsuite/
PR breakpoints/12526
* gdb.base/watch-bitfields.exp: New file.
* gdb.base/watch-bitfields.c: New file.
The IRIX support wants to set a breakpoint to be hit when the startup
phase is complete, which is where shared libraries have been mapped
in. AFAIU, for most IRIX ports, that location is the entry point.
For MIPS IRIX however, GDB needs to set a breakpoint earlier, in
__dbx_link, as explained by:
#ifdef SYS_syssgi
/* On mips-irix, we need to stop the inferior early enough during
the startup phase in order to be able to load the shared library
symbols and insert the breakpoints that are located in these shared
libraries. Stopping at the program entry point is not good enough
because the -init code is executed before the execution reaches
that point.
So what we need to do is to insert a breakpoint in the runtime
loader (rld), more precisely in __dbx_link(). This procedure is
called by rld once all shared libraries have been mapped, but before
the -init code is executed. Unfortuantely, this is not straightforward,
as rld is not part of the executable we are running, and thus we need
the inferior to run until rld itself has been mapped in memory.
For this, we trace all syssgi() syscall exit events. Each time
we detect such an event, we iterate over each text memory maps,
get its associated fd, and scan the symbol table for __dbx_link().
When found, we know that rld has been mapped, and that we can insert
the breakpoint at the symbol address. Once the dbx_link() breakpoint
has been inserted, the syssgi() notifications are no longer necessary,
so they should be canceled. */
proc_trace_syscalls_1 (pi, SYS_syssgi, PR_SYSEXIT, FLAG_SET, 0);
#endif
The loop in irix_solib_create_inferior_hook then runs until whichever
breakpoint is hit first, the one set by solib-irix.c or the one set by
procfs.c.
Note the comment in disable_break talks about __dbx_init, but I think
that's a typo for __dbx_link:
- /* Note that it is possible that we have stopped at a location that
- is different from the location where we inserted our breakpoint.
- On mips-irix, we can actually land in __dbx_init(), so we should
- not check the PC against our breakpoint address here. See procfs.c
- for more details. */
This looks very much like referring to the loop in
irix_solib_create_inferior_hook stopping at __dbx_link instead of at
the entry point.
What this patch does is convert these deprecated raw breakpoints to
standard solib_event breakpoints. When the first solib-event
breakpoint is hit, we delete all solib-event breakpoints. We do that
in the so_ops->handle_event hook.
This allows getting rid of the loop in irix_solib_create_inferior_hook
completely, which should allow properly handling signals and other
events in the early startup phase, like in SVR4.
Built on x86_64 Fedora 20 with --enable-targets=all (builds
solib-irix.c).
Joel tested that with an earlier version of this patch "info shared"
after starting a program gave the same list of shared libraries as
before.
gdb/ChangeLog:
2014-09-12 Pedro Alves <palves@redhat.com>
* breakpoint.c (remove_solib_event_breakpoints_at_next_stop)
(create_and_insert_solib_event_breakpoint): New functions.
* breakpoint.h (create_and_insert_solib_event_breakpoint)
(remove_solib_event_breakpoints_at_next_stop): New declarations.
* procfs.c (dbx_link_bpt_addr, dbx_link_bpt): Delete globals.
(remove_dbx_link_breakpoint): Delete function.
(insert_dbx_link_bpt_in_file): Use
create_and_insert_solib_event_breakpoint instead of
deprecated_insert_raw_breakpoint.
(procfs_wait): Don't check whether we hit __dbx_link here.
(procfs_mourn_inferior): Don't delete the __dbx_link breakpoint
here.
* solib-irix.c (base_breakpoint): Delete global.
(disable_break): Delete function.
(enable_break): Use create_solib_event_breakpoint
instead of deprecated_insert_raw_breakpoint.
(irix_solib_handle_event): New function.
(irix_solib_create_inferior_hook): Don't run the target or disable
the mapping-complete breakpoint here.
(_initialize_irix_solib): Install irix_solib_handle_event as
so_ops->handle_event hook.
This constifies a few functions in cli-utils -- get_number_trailer and
friends -- and then fixes the fallout.
2014-07-30 Tom Tromey <tromey@redhat.com>
* breakpoint.c (map_breakpoint_numbers): Update.
* cli/cli-utils.c (get_number_trailer): Make "pp" const. Update.
(get_number_const): New function.
(get_number): Rewrite using get_number_const.
(init_number_or_range): Make "string" const.
(number_is_in_list): Make "list" const.
* cli/cli-utils.h (get_number_const): Declare.
(struct get_number_or_range_state) <string, end_ptr>: Now const.
(init_number_or_range, number_is_in_list): Update.
* printcmd.c (map_display_numbers): Update.
* value.c (value_from_history_ref): Constify.
* value.h (value_from_history_ref): Update.
Currently, GDB can pass a signal to the wrong thread in several
different but related scenarios.
E.g., if thread 1 stops for signal SIGFOO, the user switches to thread
2, and then issues "continue", SIGFOO is actually delivered to thread
2, not thread 1. This obviously messes up programs that use
pthread_kill to send signals to specific threads.
This has been a known issue for a long while. Back in 2008 when I
made stop_signal be per-thread (2020b7ab), I kept the behavior -- see
code in 'proceed' being removed -- wanting to come back to it later.
The time has finally come now.
The patch fixes this -- on resumption, intercepted signals are always
delivered to the thread that had intercepted them.
Another example: if thread 1 stops for a breakpoint, the user switches
to thread 2, and then issues "signal SIGFOO", SIGFOO is actually
delivered to thread 1, not thread 2, because 'proceed' first switches
to thread 1 to step over its breakpoint... If the user deletes the
breakpoint before issuing "signal FOO", then the signal is delivered
to thread 2 (the current thread).
"signal SIGFOO" can be used for two things: inject a signal in the
program while the program/thread had stopped for none, bypassing
"handle nopass"; or changing/suppressing a signal the program had
stopped for. These scenarios are really two faces of the same coin,
and GDB can't really guess what the user is trying to do. GDB might
have intercepted signals in more than one thread even (see the new
signal-command-multiple-signals-pending.exp test). At least in the
inject case, it's obviously clear to me that the user means to deliver
the signal to the currently selected thread, so best is to make the
command's behavior consistent and easy to explain.
Then, if the user is trying to suppress/change a signal the program
had stopped for instead of injecting a new signal, but, the user had
changed threads meanwhile, then she will be surprised that with:
(gdb) continue
Thread 1 stopped for signal SIGFOO.
(gdb) thread 2
(gdb) signal SIGBAR
... GDB actually delivers SIGFOO to thread 1, and SIGBAR to thread 2
(with scheduler-locking off, which is the default, because then
"signal" or any other resumption command resumes all threads).
So the patch makes GDB detect that, and ask for confirmation:
(gdb) thread 1
[Switching to thread 1 (Thread 10979)]
(gdb) signal SIGUSR2
Note:
Thread 3 previously stopped with signal SIGUSR2, User defined signal 2.
Thread 2 previously stopped with signal SIGUSR1, User defined signal 1.
Continuing thread 1 (the current thread) with specified signal will
still deliver the signals noted above to their respective threads.
Continue anyway? (y or n)
All these scenarios are covered by the new tests.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-07-25 Pedro Alves <palves@redhat.com>
* NEWS: Mention signal passing and "signal" command changes.
* gdbthread.h (struct thread_suspend_state) <stop_signal>: Extend
comment.
* breakpoint.c (until_break_command): Adjust clear_proceed_status
call.
* infcall.c (run_inferior_call): Adjust clear_proceed_status call.
* infcmd.c (proceed_thread_callback, continue_1, step_once)
(jump_command): Adjust clear_proceed_status call.
(signal_command): Warn if other thread that are resumed have
signals that will be delivered. Adjust clear_proceed_status call.
(until_next_command, finish_command)
(proceed_after_attach_callback, attach_command_post_wait)
(attach_command): Adjust clear_proceed_status call.
* infrun.c (proceed_after_vfork_done): Likewise.
(proceed_after_attach_callback): Adjust comment.
(clear_proceed_status_thread): Clear stop_signal if not in pass
state.
(clear_proceed_status_callback): Delete.
(clear_proceed_status): New 'step' parameter. Only clear the
proceed status of threads the command being prepared is about to
resume.
(proceed): If passed in an explicit signal, override stop_signal
with it. Don't pass the last stop signal to the thread we're
resuming.
(init_wait_for_inferior): Adjust clear_proceed_status call.
(switch_back_to_stepped_thread): Clear the signal if it should not
be passed.
* infrun.h (clear_proceed_status): New 'step' parameter.
(user_visible_resume_ptid): Add comment.
* linux-nat.c (linux_nat_resume_callback): Don't check whether the
signal is in pass state.
* remote.c (append_pending_thread_resumptions): Likewise.
* mi/mi-main.c (proceed_thread): Adjust clear_proceed_status call.
gdb/doc/
2014-07-25 Pedro Alves <palves@redhat.com>
Eli Zaretskii <eliz@gnu.org>
* gdb.texinfo (Signaling) <signal command>: Explain what happens
with multi-threaded programs.
gdb/testsuite/
2014-07-25 Pedro Alves <palves@redhat.com>
* gdb.threads/signal-command-handle-nopass.c: New file.
* gdb.threads/signal-command-handle-nopass.exp: New file.
* gdb.threads/signal-command-multiple-signals-pending.c: New file.
* gdb.threads/signal-command-multiple-signals-pending.exp: New file.
* gdb.threads/signal-delivered-right-thread.c: New file.
* gdb.threads/signal-delivered-right-thread.exp: New file.
BINOP_RANGE was added by the following commit for chill language.
commit badefd2800
Author: Per Bothner <per@bothner.com>
Date: Wed Nov 29 22:59:31 1995 +0000
* expression.h (enum exp_opcode): Add BINOP_RANGE.
* expprint.c (dump_expression): Support BINOP_RANGE.
* eval.c (evaluate_subexp_standard): Handle BINOP_RANGE (as error).
(case MULTI_SUBSCRIPT): Fix broken f77 value->int ad hoc conversion.
* ch-lang.c (chill_op_print_tab): Support BINOP_RANGE.
(evaluate_subexp_chill): Error on BINOP_COMMA.
Chill language is no longer supported, so we can remove BINOP_RANGE too.
This patch is to remove BINOP_RANGE.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_RANGE.
* breakpoint.c (watchpoint_exp_is_const): Update.
* expprint.c (dump_subexp_body_standard): Likewise.
* eval.c (init_array_element): Remove dead code.
(evaluate_subexp_standard): Likewise.
Chill language support was removed several years ago, and BINOP_IN
isn't used for Pascal. This patch is to remove BINOP_IN.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_IN.
* breakpoint.c (watchpoint_exp_is_const): Update.
* eval.c (evaluate_subexp_standard): Likewise.
* expprint.c (dump_subexp_body_standard): Likewise.
This patch changes a few more spots to use either cmd_sfunc_ftype or
cmd_cfunc_ftype, as appropriate. This is a bit cleaner.
Tested by rebuilding.
2014-07-01 Tom Tromey <tromey@redhat.com>
* breakpoint.c (add_catch_command): Use cmd_sfunc_ftype.
* breakpoint.h (add_catch_command): Use cmd_sfunc_ftype.
* cli/cli-decode.c (cmd_cfunc_eq, add_cmd, add_prefix_cmd)
(add_abbrev_prefix_cmd, add_info, add_com): Use cmd_cfunc_ftype.
* command.h (cmd_cfunc_ftype): Move earlier.
(add_cmd, add_prefix_cmd, add_abbrev_prefix_cmd, cmd_cfunc_eq)
(add_com, add_info): Use cmd_cfunc_ftype.
This patch is to add ptid into dummy_frame and extend frame_id to
dummy_frame_id (which has a ptid field). With this change, GDB uses
dummy_frame_id (thread ptid and frame_id) to find the dummy frames.
Currently, dummy frames are looked up by frame_id, which isn't
accurate in non-stop or multi-process mode. The test case
gdb.multi/dummy-frame-restore.exp shows the problem and this patch can
fix it.
Test dummy-frame-restore.exp makes two inferiors stop at
different functions, say, inferior 1 stops at f1 while inferior 2
stops at f2. Set a breakpoint to a function, do the inferior call
in two inferiors, and GDB has two dummy frames of the same frame_id.
When the inferior call is finished, GDB will look up a dummy frame
from its stack/list and restore the inferior's regcache. Two
inferiors are finished in different orders, the inferiors' states are
restored differently, which is wrong. Running dummy-frame-restore.exp
under un-patched GDB, we'll get two fails:
FAIL: gdb.multi/dummy-frame-restore.exp: inf 2 first: after infcall: bt in inferior 2
FAIL: gdb.multi/dummy-frame-restore.exp: inf 2 first: after infcall: bt in inferior 1
With this patch applied, GDB will choose the correct dummy_frame to
restore for a given inferior, because ptid is considered when looking up
dummy frames. Two fails above are fixed.
Regression tested on x86_64-linux, both native and gdbserver.
gdb:
2014-06-27 Yao Qi <yao@codesourcery.com>
* breakpoint.c (check_longjmp_breakpoint_for_call_dummy):
Change parameter type to 'struct thread_info *'. Caller
updated.
* breakpoint.h (check_longjmp_breakpoint_for_call_dummy):
Update declaration.
* dummy-frame.c (struct dummy_frame_id): New.
(dummy_frame_id_eq): New function.
(struct dummy_frame) <id>: Change its type to 'struct
dummy_frame_id'.
(dummy_frame_push): Add parameter ptid and save it in
dummy_frame_id.
(pop_dummy_frame_bpt): Use ptid of dummy_frame instead of
inferior_ptid.
(pop_dummy_frame): Assert that the ptid of dummy_frame equals
to inferior_ptid.
(lookup_dummy_frame): Change parameter type to 'struct
dummy_frame_id *'. Callers updated. Call dummy_frame_id_eq
instead of frame_id_eq.
(dummy_frame_pop): Add parameter ptid. Callers updated.
Update comments. Compose dummy_frame_id and pass it to
lookup_dummy_frame.
(dummy_frame_discard): Add parameter ptid.
(dummy_frame_sniffer): Compose dummy_frame_id and call
dummy_frame_id_eq instead of frame_id_eq.
(fprint_dummy_frames): Print ptid.
* dummy-frame.h: Remove comments.
(dummy_frame_push): Add ptid in declaration.
(dummy_frame_pop, dummy_frame_discard): Likewise.
gdb/testsuite:
2014-06-27 Yao Qi <yao@codesourcery.com>
* gdb.multi/dummy-frame-restore.exp: New.
* gdb.multi/dummy-frame-restore.c: New.
gdb/doc:
2014-06-27 Yao Qi <yao@codesourcery.com>
* gdb.texinfo (Maintenance Commands): Update the output of
'maint print dummy-frames' command.
Generally, the blockvector ought to be readonly. So, this patch makes
the blockvector const in the symtab, and also changes various
blockvector APIs to be const.
This patch has a couple of spots that cast away const. I consider
these to be ok because they occur in mdebugread and are used while
constructing the blockvector. I have added comments at these spots.
2014-06-18 Tom Tromey <tromey@redhat.com>
* symtab.h (struct symtab) <blockvector>: Now const.
* ada-lang.c (ada_add_global_exceptions): Update.
* buildsym.c (augment_type_symtab): Update.
* dwarf2read.c (dw2_lookup_symbol): Update.
* jit.c (finalize_symtab): Update.
* jv-lang.c (add_class_symtab_symbol): Update.
* mdebugread.c (parse_symbol, add_block, sort_blocks, new_symtab):
Update.
* objfiles.c (objfile_relocate1): Update.
* psymtab.c (lookup_symbol_aux_psymtabs)
(maintenance_check_psymtabs): Update.
* python/py-symtab.c (stpy_global_block, stpy_static_block):
Update.
* spu-tdep.c (spu_catch_start): Update.
* symmisc.c (dump_symtab_1): Update.
* symtab.c (lookup_global_symbol_from_objfile)
(lookup_symbol_aux_objfile, lookup_symbol_aux_quick)
(basic_lookup_transparent_type_quick)
(basic_lookup_transparent_type, find_pc_sect_symtab)
(find_pc_sect_line, search_symbols): Update.
* block.c (find_block_in_blockvector): Make "bl" const.
(blockvector_for_pc_sect, blockvector_for_pc): Make return type
const.
(blockvector_contains_pc): Make "bv" const.
(block_for_pc_sect): Update.
* block.h (blockvector_for_pc, blockvector_for_pc_sect)
(blockvector_contains_pc): Update.
* breakpoint.c (resolve_sal_pc): Update.
* inline-frame.c (block_starting_point_at): Update.
Using the test program gdb.base/foll-fork.c, with follow-fork-mode set to
"child" and detach-on-fork set to "off", stepping or running past the fork
call results in the child process running to completion, when it should
just finish the single step. In addition, the breakpoint is not removed
from the parent process, so if it is resumed it receives a SIGTRAP.
Cause:
No matter what the setting for detach-on-fork, when stepping past a fork,
the single-step breakpoint (step_resume_breakpoint) is not handled
correctly in the parent. The SR breakpoint is cloned for the child
process, but before the clone is associated with the child it is treated as
a duplicate of the original, associated wth the parent. This results in
the insertion state of the original SR breakpoint and the clone being
"swapped" by breakpoint.c:update_global_location_list, so that the clone is
marked as inserted.
In the case where the parent is not detached, the two breakpoints remain in
that state. The breakpoint is never inserted in the child, because
although the cloned SR breakpoint is associated with the child, it is
marked as inserted. When the child is resumed, it runs to completion. The
breakpoint is never removed from the parent, so that if it is resumed after
the child exits, it gets a SIGTRAP.
Here is the sequence of events:
1) handle_inferior_event: FORK event is recognized.
2) handle_inferior_event: detach_breakpoints removes all breakpoints
from the child.
3) follow_fork: the parent SR breakpoint is cloned. Part of this procedure
is to call update_global_location_list, which swaps the insertion state of
the original and cloned SR breakpoints as part of ensuring that duplicate
breakpoints are only inserted once. At this point the original SR
breakpoint is not marked as inserted, and the clone is. The breakpoint is
actually inserted in the parent but not the child.
4) follow_fork: the original breakpoint is deleted by calling
delete_step_resume_breakpoint. Since the original is not marked as
inserted, the actual breakpoint remains in the parent process.
update_global_location_list is called again as part of the deletion. The
clone is still associated with the parent, but since it is marked as
enabled and inserted, the breakpoint is left in the parent.
5) follow_fork: if detach-on-fork is 'on', the actual breakpoint will be
removed from the parent in target_detach, based on the cloned breakpoint
still associated with the parent. Then the clone is no longer marked as
inserted. In follow_inferior_reset_breakpoints the clone is associated
with the child, and can be inserted.
If detach-on-fork is 'off', the actual breakpoint in the parent is never
removed (although the breakpoint had been deleted from the list). Since
the clone continues to be marked 'inserted', the SR breakpoint is never
inserted in the child.
Fix:
Set the cloned breakpoint as disabled from the moment it is created. This
is done by modifying clone_momentary_breakpoint to take an additional
argument, LOC_ENABLED, which is used as the value of the
bp_location->enabled member. The clone must be disabled at that point
because clone_momentary_breakpoint calls update_global_location_list, which
will swap treat the clone as a duplicate of the original breakpoint if it
is enabled.
All the calls to clone_momentary_breakpoint had to be modified to pass '1'
or '0'. I looked at implementing an enum for the enabled member, but
concluded that readability would suffer because there are so many places it
is used as a boolean, e.g. "if (bl->enabled)".
In follow_inferior_reset_breakpoints the clone is set to enabled once it
has been associated with the child process. With this, the bp_location
'inserted' member is maintained correctly throughout the follow-fork
procedure and the behavior is as expected.
The same treatment is given to the exception_resume_breakpoint when
following a fork.
Testing:
Ran 'make check' on Linux x64.
Along with the fix above, the coverage of the follow-fork test
gdb.base/foll-fork.exp was expanded to:
1) cover all the combinations of values for
follow-fork-mode and detach-on-fork
2) make sure that both user breakpoints and
single-step breakpoints are propagated
correctly to the child
3) check that the inferior list has the
expected contents after following the fork.
4) check that unfollowed, undetached inferiors
can be resumed.
gdb/
2014-06-18 Don Breazeal <donb@codesourcery.com>
* breakpoint.c (set_longjmp_breakpoint): Call
momentary_breakpoint_from_master with additional argument.
(set_longjmp_breakpoint_for_call_dummy): Call
momentary_breakpoint_from_master with additional argument.
(set_std_terminate_breakpoint): Call
momentary_breakpoint_from_master with additional argument.
(momentary_breakpoint_from_master): Add argument to function
definition and use it to initialize structure member flag.
(clone_momentary_breakpoint): Call
momentary_breakpoint_from_master with additional argument.
* infrun.c (follow_inferior_reset_breakpoints): Clear structure
member flags set in momentary_breakpoint_from_master.
gdb/testsuite/
2014-06-18 Don Breazeal <donb@codesourcery.com>
* gdb.base/foll-fork.exp (default_fork_parent_follow):
Deleted procedure.
(explicit_fork_parent_follow): Deleted procedure.
(explicit_fork_child_follow): Deleted procedure.
(test_follow_fork): New procedure.
(do_fork_tests): Replace calls to deleted procedures with
calls to test_follow_fork and reset GDB for subsequent
procedure calls.
Turns out there's a difference between loading the program with "gdb
PROGRAM", vs loading it with "(gdb) file PROGRAM". The latter results
in the objfile ending up with OBJF_USERLOADED set, while not with the
former. (That difference seems bogus, but still that's not the point
of this patch. We can revisit that afterwards.)
The new code that suppresses breakpoint removal errors for
add-symbol-file objects ends up being too greedy:
/* In some cases, we might not be able to remove a breakpoint in
a shared library that has already been removed, but we have
not yet processed the shlib unload event. Similarly for an
unloaded add-symbol-file object - the user might not yet have
had the chance to remove-symbol-file it. shlib_disabled will
be set if the library/object has already been removed, but
the breakpoint hasn't been uninserted yet, e.g., after
"nosharedlibrary" or "remove-symbol-file" with breakpoints
always-inserted mode. */
if (val
&& (bl->loc_type == bp_loc_software_breakpoint
&& (bl->shlib_disabled
|| solib_name_from_address (bl->pspace, bl->address)
|| userloaded_objfile_contains_address_p (bl->pspace,
bl->address))))
val = 0;
as it turns out that OBJF_USERLOADED can be set for objfiles loaded by
some other means not add-symbol-file. In this case, symbol-file (or
"file", which is really just "exec-file"+"symbol-file").
Recall that add-symbol-file is documented as:
(gdb) help add-symbol-file
Load symbols from FILE, assuming FILE has been dynamically loaded.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
And it's the "dynamically loaded" aspect that the breakpoint.c code
cares about. So make add-symbol-file set OBJF_SHARED on its objfiles
too, and tweak the breakpoint.c code to look for OBJF_SHARED instead
of OBJF_USERLOADED.
This restores back the missing breakpoint removal warning when we let
sss-bp-on-user-bp-2.exp run on native GNU/Linux
(https://sourceware.org/ml/gdb-patches/2014-06/msg00335.html):
(gdb) PASS: gdb.base/sss-bp-on-user-bp-2.exp: define stepi_del_break
stepi_del_break
warning: Error removing breakpoint 3
(gdb) FAIL: gdb.base/sss-bp-on-user-bp-2.exp: stepi_del_break
I say "restores" because this was GDB's behavior in 7.7 and earlier.
And, likewise, "file" with no arguments only started turning
breakpoints set in the main executable to "<pending>" with the
remote-symbol-file patch (63644780). The old behavior is now
restored, and we break-unload-file.exp test now exercizes both "gdb;
file PROGRAM" and "gdb PROGRAM".
gdb/
2014-06-16 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location, remove_breakpoint_1): Adjust.
(disable_breakpoints_in_freed_objfile): Skip objfiles that don't
have OBJF_SHARED set.
* objfiles.c (userloaded_objfile_contains_address_p): Rename to...
(shared_objfile_contains_address_p): ... this. Check OBJF_SHARED
instead of OBJF_USERLOADED.
* objfiles.h (OBJF_SHARED): Update comment.
(userloaded_objfile_contains_address_p): Rename to ...
(shared_objfile_contains_address_p): ... this, and update
comments.
* symfile.c (add_symbol_file_command): Also set OBJF_SHARED in the
new objfile.
(remove_symbol_file_command): Skip objfiles that don't have
OBJF_SHARED set.
gdb/testsuite/
2014-06-16 Pedro Alves <palves@redhat.com>
* gdb.base/break-main-file-remove-fail.c: New file.
* gdb.base/break-main-file-remove-fail.exp: New file.
* gdb.base/break-unload-file.exp: Use build_executable instead of
prepare_for_testing.
(test_break): New parameter "initial_load". Handle it.
(top level): Add initial_load cmdline/file axis.
Currently there are many calls to help_list that pass the constant -1
as the "class" value. However, the parameter is declared as being of
type enum command_class, and uses of the constant violate this
abstraction.
This patch fixes the error everywhere it occurs in the gdb sources.
Tested by rebuilding.
2014-06-13 Tom Tromey <tromey@redhat.com>
* cp-support.c (maint_cplus_command): Pass all_commands, not -1,
to help_list.
* guile/guile.c (info_guile_command): Pass all_commands, not -1,
to help_list.
* tui/tui-win.c (tui_command): Pass all_commands, not -1, to
help_list.
* tui/tui-regs.c (tui_reg_command): Pass all_commands, not -1, to
help_list.Pass all_commands, not -1, to help_list.
* cli/cli-dump.c (dump_command, append_command)
(srec_dump_command, ihex_dump_command, tekhex_dump_command)
(binary_dump_command, binary_append_command): Pass all_commands,
not -1, to help_list.
* cli/cli-cmds.c (info_command, set_debug): Pass all_commands, not
-1, to help_list.
* valprint.c (set_print, set_print_raw): Pass all_commands, not
-1, to help_list.
* typeprint.c (set_print_type): Pass all_commands, not -1, to
help_list.
* top.c (set_history): Pass all_commands, not -1, to help_list.
* target-descriptions.c (set_tdesc_cmd, unset_tdesc_cmd): Pass
all_commands, not -1, to help_list.
* symfile.c (overlay_command): Pass all_commands, not -1, to
help_list.
* spu-tdep.c (info_spu_command): Pass all_commands, not -1, to
help_list.
* serial.c (serial_set_cmd): Pass all_commands, not -1, to
help_list.
* ser-tcp.c (set_tcp_cmd, show_tcp_cmd): Pass all_commands, not
-1, to help_list.
* remote.c (remote_command, set_remote_cmd): Pass all_commands,
not -1, to help_list.
* ravenscar-thread.c (set_ravenscar_command): Pass all_commands,
not -1, to help_list.
* maint.c (maintenance_command, maintenance_info_command)
(maintenance_print_command, maintenance_set_cmd): Pass
all_commands, not -1, to help_list.
* macrocmd.c (macro_command): Pass all_commands, not -1, to
help_list.
* language.c (set_check): Pass all_commands, not -1, to help_list.
* infcmd.c (unset_command): Pass all_commands, not -1, to
help_list.
* frame.c (set_backtrace_cmd): Pass all_commands, not -1, to
help_list.
* dwarf2read.c (set_dwarf2_cmd): Pass all_commands, not -1, to
help_list.
* dcache.c (set_dcache_command): Pass all_commands, not -1, to
help_list.
* breakpoint.c (save_command): Pass all_commands, not -1, to
help_list.
* ada-lang.c (maint_set_ada_cmd, set_ada_command): Pass
all_commands, not -1, to help_list.
with the following code...
12 Nested; -- break #1
13 return I; -- break #2
14 end;
(line 12 is a call to function Nested)
... we have noticed the following errorneous behavior on ppc-aix,
where, after having inserted a breakpoint at line 12 and line 13,
and continuing from the breakpoint at line 12, the program never
stops at line 13, running away until the program terminates:
% gdb -q func
(gdb) b func.adb:12
Breakpoint 1 at 0x10000a24: file func.adb, line 12.
(gdb) b func.adb:13
Breakpoint 2 at 0x10000a28: file func.adb, line 13.
(gdb) run
Starting program: /[...]/func
Breakpoint 1, func () at func.adb:12
12 Nested; -- break #1
(gdb) c
Continuing.
[Inferior 1 (process 4128872) exited with code 02]
When resuming from the first breakpoint, GDB first tries to step out
of that first breakpoint. We rely on software single-stepping on this
platform, and it just so happens that the address of the first
software single-step breakpoint is the same as the user's breakpoint
#2 (0x10000a28). So, with infrun and target traces turned on (but
uninteresting traces snip'ed off), the "continue" operation looks like
this:
(gdb) c
### First, we insert the user breakpoints (the second one is an internal
### breakpoint on __pthread_init). The first user breakpoint is not
### inserted as we need to step out of it first.
target_insert_breakpoint (0x0000000010000a28, xxx) = 0
target_insert_breakpoint (0x00000000d03f3800, xxx) = 0
### Then we proceed with the step-out-of-breakpoint...
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=1, current thread [process 15335610] at 0x10000a24
### That's when we insert the SSS breakpoints...
target_insert_breakpoint (0x0000000010000a28, xxx) = 0
target_insert_breakpoint (0x00000000100009ac, xxx) = 0
### ... then let the inferior resume...
target_resume (15335610, continue, 0)
infrun: wait_for_inferior ()
target_wait (-1, status, options={}) = 15335610, status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: target_wait (-1, status) =
infrun: 15335610 [process 15335610],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x100009ac
### At this point, we stopped at the second SSS breakpoint...
target_stopped_by_watchpoint () = 0
### We remove the SSS breakpoints...
target_remove_breakpoint (0x0000000010000a28, xxx) = 0
target_remove_breakpoint (0x00000000100009ac, xxx) = 0
target_stopped_by_watchpoint () = 0
### We find that we're not done, so we resume....
infrun: no stepping, continue
### And thus insert the user breakpoints again, except we're not
### inserting the second breakpoint?!?
target_insert_breakpoint (0x0000000010000a24, xxx) = 0
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 15335610] at 0x100009ac
target_resume (-1, continue, 0)
infrun: prepare_to_wait
target_wait (-1, status, options={}) = 15335610, status->kind = exited, status = 2
What happens is that the removal of the software single-step
breakpoints effectively removed the breakpoint instruction from
inferior memory. But because such breakpoints are inserted directly
as raw breakpoints rather than through the normal chain of
breakpoints, we fail to notice that one of the user breakpoints points
to the same address and that this user breakpoint is therefore
effectively un-inserted. When resuming after the single-step, GDB
thinks that the user breakpoint is still inserted and therefore does
not need to insert it again.
This patch teaches the insert and remove routines of both regular and
raw breakpoints to be aware of each other. Special care needs to be
applied in case the target supports evaluation of breakpoint
conditions or commands.
gdb/ChangeLog:
PR breakpoints/17000
* breakpoint.c (find_non_raw_software_breakpoint_inserted_here):
New function, extracted from software_breakpoint_inserted_here_p.
(software_breakpoint_inserted_here_p): Replace factored out code
by call to find_non_raw_software_breakpoint_inserted_here.
(bp_target_info_copy_insertion_state): New function.
(bkpt_insert_location): Handle the case of a single-step
breakpoint already inserted at the same address.
(bkpt_remove_location): Handle the case of a single-step
breakpoint still inserted at the same address.
(deprecated_insert_raw_breakpoint): Handle the case of non-raw
breakpoint already inserted at the same address.
(deprecated_remove_raw_breakpoint): Handle the case of a
non-raw breakpoint still inserted at the same address.
(find_single_step_breakpoint): New function, extracted from
single_step_breakpoint_inserted_here_p.
(find_single_step_breakpoint): New function,
factored out from single_step_breakpoint_inserted_here_p.
(single_step_breakpoint_inserted_here_p): Reimplement.
gdb/testsuite/ChangeLog:
PR breakpoints/17000
* gdb.base/sss-bp-on-user-bp.exp: Remove kfail.
* gdb.base/sss-bp-on-user-bp-2.exp: Remove kfail.
Tested on ppc-aix with AdaCore's testsuite. Tested on x86_64-linux,
(native and gdbserver) with the official testsuite. Also tested on
x86_64-linux through Pedro's branch enabling software single-stepping
on that platform (native and gdbserver).
While the full fix for PR 15180 isn't in, it's best if we at least
make sure that GDB doesn't lose control when a breakpoint is set at
the same address as a dprintf.
gdb/
2014-06-02 Pedro Alves <palves@redhat.com>
* breakpoint.c (build_target_command_list): Don't build a command
list if we have any duplicate location that isn't a dprintf.
gdb/testsuite/
2014-06-02 Pedro Alves <palves@redhat.com>
* gdb.base/dprintf-bp-same-addr.c: New file.
* gdb.base/dprintf-bp-same-addr.exp: New file.
If some event happens to trigger at the same address as a dprintf-style
agent dprintf is installed, GDB will complain, like:
(gdb) continue
Continuing.
May only run agent-printf on the target
(gdb)
Such dprintfs are completely handled on the target side, so they can't
explain a stop, but GDB is currently putting then on the bpstat chain
anyway, because they currently unconditionally use bkpt_breakpoint_hit
as breakpoint_hit method.
gdb/
2014-06-02 Pedro Alves <palves@redhat.com>
* breakpoint.c (dprintf_breakpoint_hit): New function.
(initialize_breakpoint_ops): Install it as dprintf's
breakpoint_hit method.
Move infrun.c declarations out of inferior.h to a new infrun.h file.
Tested by building on:
i686-w64-mingw32, enable-targets=all
x86_64-linux, enable-targets=all
i586-pc-msdosdjgpp
And also grepped the whole tree for each symbol moved to find where
infrun.h might be necessary.
gdb/
2014-05-22 Pedro Alves <palves@redhat.com>
* inferior.h (debug_infrun, debug_displaced, stop_on_solib_events)
(sync_execution, sched_multi, step_stop_if_no_debug, non_stop)
(disable_randomization, enum exec_direction_kind)
(execution_direction, stop_registers, start_remote)
(clear_proceed_status, proceed, resume, user_visible_resume_ptid)
(wait_for_inferior, normal_stop, get_last_target_status)
(prepare_for_detach, fetch_inferior_event, init_wait_for_inferior)
(insert_step_resume_breakpoint_at_sal)
(follow_inferior_reset_breakpoints, stepping_past_instruction_at)
(set_step_info, print_stop_event, signal_stop_state)
(signal_print_state, signal_pass_state, signal_stop_update)
(signal_print_update, signal_pass_update)
(update_signals_program_target, clear_exit_convenience_vars)
(displaced_step_dump_bytes, update_observer_mode)
(signal_catch_update, gdb_signal_from_command): Move
declarations ...
* infrun.h: ... to this new file.
* amd64-tdep.c: Include infrun.h.
* annotate.c: Include infrun.h.
* arch-utils.c: Include infrun.h.
* arm-linux-tdep.c: Include infrun.h.
* arm-tdep.c: Include infrun.h.
* break-catch-sig.c: Include infrun.h.
* breakpoint.c: Include infrun.h.
* common/agent.c: Include infrun.h instead of inferior.h.
* corelow.c: Include infrun.h.
* event-top.c: Include infrun.h.
* go32-nat.c: Include infrun.h.
* i386-tdep.c: Include infrun.h.
* inf-loop.c: Include infrun.h.
* infcall.c: Include infrun.h.
* infcmd.c: Include infrun.h.
* infrun.c: Include infrun.h.
* linux-fork.c: Include infrun.h.
* linux-nat.c: Include infrun.h.
* linux-thread-db.c: Include infrun.h.
* monitor.c: Include infrun.h.
* nto-tdep.c: Include infrun.h.
* procfs.c: Include infrun.h.
* record-btrace.c: Include infrun.h.
* record-full.c: Include infrun.h.
* remote-m32r-sdi.c: Include infrun.h.
* remote-mips.c: Include infrun.h.
* remote-notif.c: Include infrun.h.
* remote-sim.c: Include infrun.h.
* remote.c: Include infrun.h.
* reverse.c: Include infrun.h.
* rs6000-tdep.c: Include infrun.h.
* s390-linux-tdep.c: Include infrun.h.
* solib-irix.c: Include infrun.h.
* solib-osf.c: Include infrun.h.
* solib-svr4.c: Include infrun.h.
* target.c: Include infrun.h.
* top.c: Include infrun.h.
* windows-nat.c: Include infrun.h.
* mi/mi-interp.c: Include infrun.h.
* mi/mi-main.c: Include infrun.h.
* python/py-threadevent.c: Include infrun.h.
Without the code portion of the patch, we get these failures:
FAIL: gdb.base/break-unload-file.exp: always-inserted on: break: continue
FAIL: gdb.base/break-unload-file.exp: always-inserted on: hbreak: continue
FAIL: gdb.base/sym-file.exp: stale bkpts: continue to breakpoint: end here
They all looks like random SIGTRAPs:
continue
Continuing.
Program received signal SIGTRAP, Trace/breakpoint trap.
0x0000000000400541 in foo () at ../../../src/gdb/testsuite/gdb.base/break-unload-file.c:21
21 }
(gdb) FAIL: gdb.base/break-unload-file.exp: always-inserted on: break: continue
(This is a regression caused by the remove-symbol-file command
series.)
break-unload-file.exp is about having breakpoints inserted, and then
doing "file". I caught this while writing a test that does "file
PROGRAM", while PROGRAM was already loaded, which internally does
"file" first, because I wanted to force a breakpoint_re_set, but the
test is more explicit in case GDB ever optimizes out that re-set.
The problem is that unloading the file with "file" ends up in
disable_breakpoints_in_freed_objfile, which marks all breakpoint
locations of the objfile as both shlib_disabled, _and_ clears the
inserted flag, without actually removing the breakpoints from the
inferior. Now, usually, in all-stop, breakpoints will already be
removed from the inferior before the user can issue the "file"
command, but, with non-stop, or breakpoints always-inserted on mode,
breakpoints stay inserted even while the user has the prompt. In the
latter case, then, if we let the program continue, and it executes the
address where we had previously set the breakpoint, it'll actually
execute the breakpoint instruction that we left behind...
Now, one issue is that the intent of
disable_breakpoints_in_freed_objfile is really to handle the unloading
of OBJF_USERLOADED objfiles. These are objfiles that were added with
add-symbol-file and that are removed with remove-symbol-file.
"add-symbol-file"'s docs in the manual clearly say these commands are
used to let GDB know about dynamically loaded code:
You would use this command when @var{filename} has been dynamically
loaded (by some other means) into the program that is running.
Similarly, the online help says:
(gdb) help add-symbol-file
Load symbols from FILE, assuming FILE has been dynamically loaded.
So it makes sense to, like when shared libraries are unloaded through
the generic solib machinery, mark the breakpoint locations as
shlib_disabled. But, the "file" command is not about dynamically
loaded code, it's about the main program. So the patch makes
disable_breakpoints_in_freed_objfile skip all objfiles but
OBJF_USERLOADED ones, thus skipping the main objfile.
Then, the reason that disable_breakpoints_in_freed_objfile was
clearing the inserted flag isn't clear, but likely to avoid breakpoint
removal errors, assuming remove-symbol-file was called after the
dynamic object was already unmapped from the inferior. In that case,
it'd okay to simply clear the inserted flag, but not so if the user
for example does remove-symbol-file to remove the library because he
made a mistake in the library's address, and wants to re-do
add-symbol-file with the correct address.
To address all that, I propose an alternative implementation, that
handles both cases. The patch includes changes to sym-file.exp to
cover them.
This implementation leaves the inserted flag alone, and handles
breakpoint insertion/removal failure gracefully when the locations are
in OBJF_USERLOADED objfiles, just like we handle insertion/removal
failure gracefully for locations in shared libraries.
To try to make sure we aren't patching back stale shadow memory
contents into the inferior, in case the program mapped a different
library at the same address where we had the breakpoint, without the
user having had a chance of remove-symbol-file'ing before, this adds a
new memory_validate_breakpoint function that checks if the breakpoint
instruction is still in memory. ppc_linux_memory_remove_breakpoint
does this unconditionally for all memory breakpoints, and questions
whether memory_remove_breakpoint should be changed to do this for all
breakpoints. Possibly yes, though I'm not certain, hence this
baby-steps patch.
Tested on x86_64 Fedora 17, native and gdbserver.
gdb/
2014-04-23 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Tolerate errors if the
breakpoint is set in a user-loaded objfile.
(remove_breakpoint_1): Likewise. Also tolerate errors if the
location is marked shlib_disabled. If the breakpoint is set in a
user-loaded objfile is a GDB-side memory breakpoint, validate it
before uninsertion. (disable_breakpoints_in_freed_objfile): Skip
non-OBJF_USERLOADED objfiles. Don't clear the location's inserted
flag.
* mem-break.c (memory_validate_breakpoint): New function.
* objfiles.c (userloaded_objfile_contains_address_p): New
function.
* objfiles.h (userloaded_objfile_contains_address_p): Declare.
* target.h (memory_validate_breakpoint): New declaration.
gdb/testsuite/
2014-04-23 Pedro Alves <palves@redhat.com>
* gdb.base/break-unload-file.c: New file.
* gdb.base/break-unload-file.exp: New file.
* gdb.base/sym-file-lib.c (baz): New function.
* gdb.base/sym-file-loader.c (struct segment) <mapped_size>: New
field.
(load): Store the segment's mapped size.
(unload): New function.
(unload_shlib): New function.
* gdb.base/sym-file-loader.h (unload_shlib): New declaration.
* gdb.base/sym-file-main.c (main): Unload, and reload the library,
set a breakpoint at baz, and call it.
* gdb.base/sym-file.exp: New tests for stale breakpoint
instructions.
libraries.
As explained in
https://sourceware.org/ml/gdb-patches/2008-08/msg00361.html, after a
shared library was unloaded, we can no longer insert or remove
breakpoints into/from its (no longer present) code segment. That'll
fail with memory errors. However, that concern does not apply to
hardware breakpoints. By definition, hardware breakpoints are
implemented using a mechanism that is not dependent on being able to
modify the target's memory. Usually, by setting up CPU debug
registers. IOW, we should be able to set hw breakpoints in an
unmapped address. We don't seem to have a test that exercises that,
so this patch adds one.
I noticed the error supression because of a related issue -- the
target_insert_hw_breakpoint/target_remove_hw_breakpoint interfaces
don't really distinguish "not supported" from "error" return, and so
remote.c returns -1 in both cases. This results in hardware
breakpoints set in shared libraries silently ending up pending forever
even though the target doesn't actually support hw breakpoints.
(gdb) set breakpoint always-inserted on
(gdb) set remote Z-packet off
(gdb) info breakpoints
No breakpoints or watchpoints.
(gdb) hbreak shrfunc
Hardware assisted breakpoint 3 at 0x7ffff7dfb657: file ../../../src/gdb/testsuite/gdb.base/hbreak-in-shr-unsupported-shr.c, line 21.
(gdb) info break
Num Type Disp Enb Address What
3 hw breakpoint keep y <PENDING> shrfunc
After the patch we get the expected:
(gdb) hbreak shrfunc
Hardware assisted breakpoint 3 at 0x7ffff7dfb657: file ../../../src/gdb/testsuite/gdb.base/hbreak-in-shr-unsupported-shr.c, line 21.
Warning:
Cannot insert hardware breakpoint 3.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.
(gdb) info break
Num Type Disp Enb Address What
3 hw breakpoint keep y 0x00007ffff7dfb657 in shrfunc at ../../../src/gdb/testsuite/gdb.base/hbreak-in-shr-unsupported-shr.c:21
(HW breakpoints set in the main executable, when the target doesn't
support HW breakpoints always resulted in the latter output.)
We probably should improve the insert/remove interface to return a
different error code for unsupported. But I chose to fix the error
supression first, as it's a deeper and wider issue.
Tested on x86_64 Fedora 17, native and gdbserver.
gdb/
2014-04-23 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location, remove_breakpoint_1): If
the breakpoint is set in a shared library, only suppress
errors for software breakpoints, not hardware breakpoints.
gdb/testsuite/
2014-04-23 Pedro Alves <palves@redhat.com>
* gdb.base/hbreak-in-shr-unsupported-shr.c: New file.
* gdb.base/hbreak-in-shr-unsupported.c: New file.
* gdb.base/hbreak-in-shr-unsupported.exp: New file.
* gdb.base/hbreak-unmapped.c: New file.
* gdb.base/hbreak-unmapped.exp: New file.
* gdb.trace/qtro.exp (gdb_is_target_remote): Move ...
* lib/gdb.exp (gdb_is_target_remote): ... here.
Breakpoints are supposed to be transparent to memory accesses. For
all kinds of breakpoints breakpoint_xfer_memory hides the breakpoint
instructions. However, sss breakpoints aren't tracked like all other
breakpoints, and nothing is taking care of hiding them from memory
reads.
Say, as is, a background step + disassemble will see breakpoints
instructions on software step targets. E.g., stepping over this line:
while (1);
with s&
and then "disassemble" would show sss breakpoints.
Actually, that's still not be possible to see today, because:
- in native Linux, you can't read memory while the program
is running.
- with Linux gdbserver, you can, but in the all-stop RSP you
can't talk to the server while the program is running...
- and with non-stop, on software step targets, we presently
force the use of displaced-stepping for all single-steps,
so no single-step breakpoints are used...
I've been working towards making non-stop not force displaced stepping
on sss targets, and I noticed the issue then. With that, I indeed see
this:
(gdb) set remote Z-packet off
(gdb) s&
(gdb) disassemble main
Dump of assembler code for function main:
0x000000000040049c <+0>: push %rbp
0x000000000040049d <+1>: mov %rsp,%rbp
0x00000000004004a0 <+4>: int3
0x00000000004004a1 <+5>: (bad)
End of assembler dump.
Instead of the correct:
(gdb) disassemble main
Dump of assembler code for function main:
0x000000000040049c <+0>: push %rbp
0x000000000040049d <+1>: mov %rsp,%rbp
0x00000000004004a0 <+4>: jmp 0x4004a0 <main+4>
This is actually one thing that my v1 of the recent "fix a bunch of
run control bugs" series was fixing, because it made sss breakpoints
be regular breakpoints in the breakpoint chain. But dropped it in the
version that landed in the tree, due to some problems.
So instead of making sss breakpoints regular breakpoints, go with a
simpler fix (at least for now) -- make breakpoint_xfer_memory take
software single-step breakpoints into account. After the patch, I get
the correct disassemble output.
Tested on x86_64 Fedora 17, and also on top of my "use software
single-step on x86" series.
Also fixes the issue pointed out by Yao at
https://sourceware.org/ml/gdb-patches/2014-04/msg00045.html, where the
prologue analysis/frame sniffing manages to see software step
breakpoint instructions.
gdb/
2014-04-10 Pedro Alves <palves@redhat.com>
* breakpoint.c (single_step_breakpoints)
(single_step_gdbarch): Move up in the file.
(one_breakpoint_xfer_memory): New function, factored out from ...
(breakpoint_xfer_memory): ... here. Also process single-step
breakpoints.
Even with deferred_step_ptid out of the way, GDB can still lose
watchpoints.
If a watchpoint triggers and the PC points to an address where a
thread-specific breakpoint for another thread is set, the thread-hop
code triggers, and we lose the watchpoint:
if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
{
int thread_hop_needed = 0;
struct address_space *aspace =
get_regcache_aspace (get_thread_regcache (ecs->ptid));
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
{
if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
thread_hop_needed = 1;
^^^^^^^^^^^^^^^^^^^^^
}
And on software single-step targets, even without a thread-specific
breakpoint in the way, here in the thread-hop code:
else if (singlestep_breakpoints_inserted_p)
{
...
if (!ptid_equal (singlestep_ptid, ecs->ptid)
&& in_thread_list (singlestep_ptid))
{
/* If the PC of the thread we were trying to single-step
has changed, discard this event (which we were going
to ignore anyway), and pretend we saw that thread
trap. This prevents us continuously moving the
single-step breakpoint forward, one instruction at a
time. If the PC has changed, then the thread we were
trying to single-step has trapped or been signalled,
but the event has not been reported to GDB yet.
There might be some cases where this loses signal
information, if a signal has arrived at exactly the
same time that the PC changed, but this is the best
we can do with the information available. Perhaps we
should arrange to report all events for all threads
when they stop, or to re-poll the remote looking for
this particular thread (i.e. temporarily enable
schedlock). */
CORE_ADDR new_singlestep_pc
= regcache_read_pc (get_thread_regcache (singlestep_ptid));
if (new_singlestep_pc != singlestep_pc)
{
enum gdb_signal stop_signal;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
" but expected thread advanced also\n");
/* The current context still belongs to
singlestep_ptid. Don't swap here, since that's
the context we want to use. Just fudge our
state and continue. */
stop_signal = ecs->event_thread->suspend.stop_signal;
ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
ecs->ptid = singlestep_ptid;
ecs->event_thread = find_thread_ptid (ecs->ptid);
ecs->event_thread->suspend.stop_signal = stop_signal;
stop_pc = new_singlestep_pc;
}
else
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: unexpected thread\n");
thread_hop_needed = 1;
stepping_past_singlestep_breakpoint = 1;
saved_singlestep_ptid = singlestep_ptid;
}
}
}
we either end up with thread_hop_needed, ignoring the watchpoint
SIGTRAP, or switch to the stepping thread, again ignoring that the
SIGTRAP could be for some other event.
The new test added by this patch exercises both paths.
So the fix is similar to the deferred_step_ptid fix -- defer the
thread hop to _after_ the SIGTRAP had a change of passing through the
regular bpstat handling. If the wrong thread hits a breakpoint, we'll
just end up with BPSTAT_WHAT_SINGLE, and if nothing causes a stop,
keep_going starts a step-over.
Most of the stepping_past_singlestep_breakpoint mechanism is really
not necessary -- setting the thread to step over a breakpoint with
thread->trap_expected is sufficient to keep all other threads locked.
It's best to still keep the flag in some form though, because when we
get to keep_going, the software single-step breakpoint we need to step
over is already gone -- an optimization done by a follow up patch will
check whether a step-over is still be necessary by looking to see
whether the breakpoint is still there, and would find the thread no
longer needs a step-over, while we still want it.
Special care is still needed to handle the case of PC of the thread we
were trying to single-step having changed, like in the old code. We
can't just keep_going and re-step it, as in that case we can over-step
the thread (if it was already done with the step, but hasn't reported
it yet, we'd ask it to step even further). That's now handled in
switch_back_to_stepped_thread. As bonus, we're now using a technique
that doesn't lose signals, unlike the old code -- we now insert a
breakpoint at PC, and resume, which either reports the breakpoint
immediately, or any pending signal.
Tested on x86_64 Fedora 17, against pristine mainline, and against a
branch that implements software single-step on x86.
gdb/
2014-03-20 Pedro Alves <palves@redhat.com>
* breakpoint.c (single_step_breakpoint_inserted_here_p): Make
extern.
* breakpoint.h (single_step_breakpoint_inserted_here_p): Declare.
* infrun.c (saved_singlestep_ptid)
(stepping_past_singlestep_breakpoint): Delete.
(resume): Remove stepping_past_singlestep_breakpoint handling.
(proceed): Store the prev_pc of the stepping thread too.
(init_wait_for_inferior): Adjust. Clear singlestep_ptid and
singlestep_pc.
(enum infwait_states): Delete infwait_thread_hop_state.
(struct execution_control_state) <hit_singlestep_breakpoint>: New
field.
(handle_inferior_event): Adjust.
(handle_signal_stop): Delete stepping_past_singlestep_breakpoint
handling and the thread-hop code. Before removing single-step
breakpoints, check whether the thread hit a single-step breakpoint
of another thread. If it did, the trap is not a random signal.
(switch_back_to_stepped_thread): If the event thread hit a
single-step breakpoint, unblock it before switching to the
stepping thread. Handle the case of the stepped thread having
advanced already.
(keep_going): Handle the case of the current thread moving past a
single-step breakpoint.
gdb/testsuite/
2014-03-20 Pedro Alves <palves@redhat.com>
* gdb.threads/step-over-trips-on-watchpoint.c: New file.
* gdb.threads/step-over-trips-on-watchpoint.exp: New file.
Say the program is stopped at a breakpoint, and the user sets a
watchpoint. When the program is next resumed, GDB will first step
over the breakpoint, as explained in the manual:
@value {GDBN} normally ignores breakpoints when it resumes
execution, until at least one instruction has been executed. If it
it did not do this, you would be unable to proceed past a breakpoint
without first disabling the breakpoint. This rule applies whether
or not the breakpoint already existed when your program stopped.
However, GDB currently also removes watchpoints, catchpoints, etc.,
and that means that the first instruction off the breakpoint does not
trigger the watchpoint, catchpoint, etc.
testsuite/gdb.base/watchpoint.exp has a kfail for this.
The PR proposes installing watchpoints only when stepping over a
breakpoint, but that misses catchpoints, etc.
A better fix would instead work from the opposite direction -- remove
only real breakpoints, leaving all other kinds of breakpoints
inserted.
But, going further, it's really a waste to constantly remove/insert
all breakpoints when stepping over a single breakpoint (generating a
pair of RSP z/Z packets for each breakpoint), so the fix goes a step
further and makes GDB remove _only_ the breakpoint being stepped over,
leaving all others installed. This then has the added benefit of
reducing breakpoint-related RSP traffic substancialy when there are
many breakpoints set.
gdb/
2014-03-20 Pedro Alves <palves@redhat.com>
PR breakpoints/7143
* breakpoint.c (should_be_inserted): Don't insert breakpoints that
are being stepped over.
(breakpoint_address_match): Make extern.
* breakpoint.h (breakpoint_address_match): New declaration.
* inferior.h (stepping_past_instruction_at): New declaration.
* infrun.c (struct step_over_info): New type.
(step_over_info): New global.
(set_step_over_info, clear_step_over_info)
(stepping_past_instruction_at): New functions.
(handle_inferior_event): Clear the step-over info when
trap_expected is cleared.
(resume): Remove now stale comment.
(clear_proceed_status): Clear step-over info.
(proceed): Adjust step-over handling to set or clear the step-over
info instead of removing all breakpoints.
(handle_signal_stop): When setting up a thread-hop, don't remove
breakpoints here.
(stop_stepping): Clear step-over info.
(keep_going): Adjust step-over handling to set or clear step-over
info and then always inserting breakpoints, instead of removing
all breakpoints when stepping over one.
gdb/testsuite/
2014-03-20 Pedro Alves <palves@redhat.com>
PR breakpoints/7143
* gdb.base/watchpoint.exp: Mention bugzilla bug number instead of
old gnats gdb/38. Remove kfail. Adjust to use gdb_test instead
of gdb_test_multiple.
* gdb.cp/annota2.exp: Remove kfail for gdb/38.
* gdb.cp/annota3.exp: Remove kfail for gdb/38.
This patch is to remove parameter optional_p as it is always true,
in order to simplify get_tracepoint_by_number.
'optional_p' was added by this change,
1999-11-18 Tom Tromey <tromey@cygnus.com>
* tracepoint.h (get_tracepoint_by_number): Updated
declaration.
* tracepoint.c (trace_pass_command): Better error message.
Fixed logic when `all' not specified.
(get_tracepoint_by_number): Added `optional_p' argument. Fixed
all callers.
but after this patch,
FYI: remove `static's from cli-utils.c
https://sourceware.org/ml/gdb-patches/2011-03/msg00636.html
'optional_p' passed to get_tracepoint_by_number become always true.
gdb:
2014-03-06 Yao Qi <yao@codesourcery.com>
* breakpoint.c (get_tracepoint_by_number): Remove argument
optional_p. All callers updated. Adjust comments. Update
output message.
* breakpoint.h (get_tracepoint_by_number): Update declaration.
This changes the probes to be independent of the program space.
After this, when a probe's address is needed, it is determined by
applying offsets at the point of use.
This introduces a bound_probe object, similar to bound minimal
symbols. Objects of this type are used when it's necessary to pass a
probe and its corresponding objfile.
This removes the backlink from probe to objfile, which was primarily
used to fetch the architecture to use.
This adds a get_probe_address function which calls a probe method to
compute the probe's relocated address. Similarly, it adds an objfile
parameter to the semaphore methods so they can do the relocation
properly as well.
2014-03-03 Tom Tromey <tromey@redhat.com>
* break-catch-throw.c (fetch_probe_arguments): Use bound probes.
* breakpoint.c (create_longjmp_master_breakpoint): Use
get_probe_address.
(add_location_to_breakpoint, bkpt_probe_insert_location)
(bkpt_probe_remove_location): Update.
* breakpoint.h (struct bp_location) <probe>: Now a bound_probe.
* elfread.c (elf_symfile_relocate_probe): Remove.
(elf_probe_fns): Update.
(insert_exception_resume_breakpoint): Change type of "probe"
parameter to bound_probe.
(check_exception_resume): Update.
* objfiles.c (objfile_relocate1): Don't relocate probes.
* probe.c (bound_probe_s): New typedef.
(parse_probes): Use get_probe_address. Set sal's objfile.
(find_probe_by_pc): Return a bound_probe.
(collect_probes): Return a VEC(bound_probe_s).
(compare_probes): Update.
(gen_ui_out_table_header_info): Change type of "probes"
parameter. Update.
(info_probes_for_ops): Update.
(get_probe_address): New function.
(probe_safe_evaluate_at_pc): Update.
* probe.h (struct probe_ops) <get_probe_address>: New field.
<set_semaphore, clear_semaphore>: Add objfile parameter.
(struct probe) <objfile>: Remove field.
<arch>: New field.
<address>: Update comment.
(struct bound_probe): New.
(find_probe_by_pc): Return a bound_probe.
(get_probe_address): Declare.
* solib-svr4.c (struct probe_and_action) <address>: New field.
(hash_probe_and_action, equal_probe_and_action): Update.
(register_solib_event_probe): Add address parameter.
(solib_event_probe_at): Update.
(svr4_create_probe_breakpoints): Add objfile parameter. Use
get_probe_address.
* stap-probe.c (struct stap_probe) <sem_addr>: Update comment.
(stap_get_probe_address): New function.
(stap_can_evaluate_probe_arguments, compute_probe_arg)
(compile_probe_arg): Update.
(stap_set_semaphore, stap_clear_semaphore): Compute semaphore's
address.
(handle_stap_probe): Don't relocate the probe.
(stap_relocate): Remove.
(stap_gen_info_probes_table_values): Update.
(stap_probe_ops): Remove stap_relocate.
* symfile-debug.c (debug_sym_relocate_probe): Remove.
(debug_sym_probe_fns): Update.
* symfile.h (struct sym_probe_fns) <sym_relocate_probe>: Remove.
* symtab.c (init_sal): Use memset.
* symtab.h (struct symtab_and_line) <objfile>: New field.
* tracepoint.c (start_tracing, stop_tracing): Update.
With the test changed as in the patch, against current mainline, we get:
(gdb) PASS: gdb.ada/tasks.exp: info tasks before inserting breakpoint
break break_me task 1
Breakpoint 2 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 1
break break_me task 3
Note: breakpoint 2 also set at pc 0x4030b0.
Breakpoint 3 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 3
continue
Continuing.
[Switching to Thread 0x7ffff7dc7700 (LWP 27133)]
Breakpoint 2, foo.break_me () at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb:27
27 null;
(gdb) FAIL: gdb.ada/tasks.exp: continue to breakpoint
info tasks
ID TID P-ID Pri State Name
1 63b010 48 Waiting on RV with 3 main_task
2 63bd80 1 48 Accept or Select Term task_list(1)
* 3 63f510 1 48 Accepting RV with 1 task_list(2)
4 642ca0 1 48 Accept or Select Term task_list(3)
(gdb) PASS: gdb.ada/tasks.exp: info tasks after hitting breakpoint
The breakpoint that caused a stop is breakpoint 3, but GDB end up
reporting (and running breakpoint commands of) "Breakpoint 2" instead.
The issue is that the bpstat_check_breakpoint_conditions logic of
"wrong thread" is missing the "wrong task" check. This is usually
harmless, because the thread hop code in infrun.c code that handles
wrong-task-hitting-breakpoint does check for task-specific breakpoints
(within breakpoint_thread_match):
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
{
if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
thread_hop_needed = 1;
}
IOW, usually, when one only has a task specific breakpoint at a given
address, things work correctly. Put another task-specific or
non-task-specific breakpoint there, and things break.
A patch that eliminates the special thread hop code in infrun.c is
what exposed this, as after that GDB solely relies on
bpstat_check_breakpoint_conditions to know whether the right or wrong
task hit a breakpoint. IOW, given the latent bug, Ada task-specific
breakpoints become non-task-specific, and that is caught by the
testsuite, as:
break break_me task 3
Breakpoint 2 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 3
continue
Continuing.
[Switching to Thread 0x7ffff7fcb700 (LWP 17122)]
Breakpoint 2, foo.break_me () at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb:27
27 null;
(gdb) PASS: gdb.ada/tasks.exp: continue to breakpoint
info tasks
ID TID P-ID Pri State Name
1 63b010 48 Waiting on RV with 2 main_task
* 2 63bd80 1 48 Accepting RV with 1 task_list(1)
3 63f510 1 48 Accept or Select Term task_list(2)
4 642ca0 1 48 Accept or Select Term task_list(3)
(gdb) FAIL: gdb.ada/tasks.exp: info tasks after hitting breakpoint
It was after seeing this that I thought of how to expose the bug with
current mainline.
Tested on x86_64 Fedora 17.
gdb/
2014-02-26 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_check_breakpoint_conditions): Handle
task-specific breakpoints.
gdb/testsuite/
2014-02-26 Pedro Alves <palves@redhat.com>
* gdb.ada/tasks.exp: Set a task-specific breakpoint at break_me
that won't ever trigger. Make sure that GDB reports the correct
breakpoint that caused the stop.
* configure.ac (libpython checking): Remove all but python.o from
CONFIG_OBS. Remove all but python.c from CONFIG_SRCS.
* configure: Regenerate.
* Makefile.in (SFILES): Add extension.c.
(HFILES_NO_SRCDIR): Add extension.h, extension-priv.h
(COMMON_OBS): Add extension.o.
* extension.h: New file.
* extension-priv.h: New file.
* extension.c: New file.
* python/python-internal.h: #include "extension.h".
(gdbpy_auto_load_enabled): Declare.
(gdbpy_apply_val_pretty_printer): Declare.
(gdbpy_apply_frame_filter): Declare.
(gdbpy_preserve_values): Declare.
(gdbpy_breakpoint_cond_says_stop): Declare.
(gdbpy_breakpoint_has_cond): Declare.
(void source_python_script_for_objfile): Delete.
* python/python.c: #include "extension-priv.h".
Delete inclusion of "observer.h".
(extension_language_python): Moved here and renamed from
script_language_python in py-auto-load.c.
Redefined to be of type extension_language_defn.
(python_extension_script_ops): New global.
(python_extension_ops): New global.
(struct python_env): New member previous_active.
(restore_python_env): Call restore_active_ext_lang.
(ensure_python_env): Call set_active_ext_lang.
(gdbpy_clear_quit_flag): Renamed from clear_quit_flag, made static.
New arg extlang.
(gdbpy_set_quit_flag): Renamed from set_quit_flag, made static.
New arg extlang.
(gdbpy_check_quit_flag): Renamed from check_quit_flag, made static.
New arg extlang.
(gdbpy_eval_from_control_command): Renamed from
eval_python_from_control_command, made static. New arg extlang.
(gdbpy_source_script) Renamed from source_python_script, made static.
New arg extlang.
(gdbpy_before_prompt_hook): Renamed from before_prompt_hook. Change
result to int. New arg extlang.
(gdbpy_source_objfile_script): Renamed from
source_python_script_for_objfile, made static. New arg extlang.
(gdbpy_start_type_printers): Renamed from start_type_printers, made
static. New args extlang, extlang_printers. Change result type to
"void".
(gdbpy_apply_type_printers): Renamed from apply_type_printers, made
static. New arg extlang. Rename arg printers to extlang_printers
and change type to ext_lang_type_printers *.
(gdbpy_free_type_printers): Renamed from free_type_printers, made
static. Replace argument arg with extlang, extlang_printers.
(!HAVE_PYTHON, eval_python_from_control_command): Delete.
(!HAVE_PYTHON, source_python_script): Delete.
(!HAVE_PYTHON, gdbpy_should_stop): Delete.
(!HAVE_PYTHON, gdbpy_breakpoint_has_py_cond): Delete.
(!HAVE_PYTHON, start_type_printers): Delete.
(!HAVE_PYTHON, apply_type_printers): Delete.
(!HAVE_PYTHON, free_type_printers): Delete.
(_initialize_python): Delete call to observer_attach_before_prompt.
(finalize_python): Set/restore active extension language.
(gdbpy_finish_initialization) Renamed from
finish_python_initialization, made static. New arg extlang.
(gdbpy_initialized): New function.
* python/python.h: #include "extension.h". Delete #include
"value.h", "mi/mi-cmds.h".
(extension_language_python): Declare.
(GDBPY_AUTO_FILE_NAME): Delete.
(enum py_bt_status): Moved to extension.h and renamed to
ext_lang_bt_status.
(enum frame_filter_flags): Moved to extension.h.
(enum py_frame_args): Moved to extension.h and renamed to
ext_lang_frame_args.
(finish_python_initialization): Delete.
(eval_python_from_control_command): Delete.
(source_python_script): Delete.
(apply_val_pretty_printer): Delete.
(apply_frame_filter): Delete.
(preserve_python_values): Delete.
(gdbpy_script_language_defn): Delete.
(gdbpy_should_stop, gdbpy_breakpoint_has_py_cond): Delete.
(start_type_printers, apply_type_printers, free_type_printers): Delete.
* auto-load.c: #include "extension.h".
(GDB_AUTO_FILE_NAME): Delete.
(auto_load_gdb_scripts_enabled): Make public. New arg extlang.
(script_language_gdb): Delete, moved to extension.c and renamed to
extension_language_gdb.
(source_gdb_script_for_objfile): Delete.
(auto_load_pspace_info): New member unsupported_script_warning_printed.
(loaded_script): Change type of language member to
struct extension_language_defn *.
(init_loaded_scripts_info): Initialize
unsupported_script_warning_printed.
(maybe_add_script): Make static. Change type of language arg to
struct extension_language_defn *.
(clear_section_scripts): Reset unsupported_script_warning_printed.
(auto_load_objfile_script_1): Rewrite to use extension language API.
(auto_load_objfile_script): Make public. Remove support-compiled-in
and auto-load-enabled checks, moved to auto_load_scripts_for_objfile.
(source_section_scripts): Rewrite to use extension language API.
(load_auto_scripts_for_objfile): Rewrite to use
auto_load_scripts_for_objfile.
(collect_matching_scripts_data): Change type of language member to
struct extension_language_defn *.
(auto_load_info_scripts): Change type of language arg to
struct extension_language_defn *.
(unsupported_script_warning_print): New function.
(script_not_found_warning_print): Make static.
(_initialize_auto_load): Rewrite construction of scripts-directory
help.
* auto-load.h (struct objfile): Add forward decl.
(struct script_language): Delete.
(struct auto_load_pspace_info): Add forward decl.
(struct extension_language_defn): Add forward decl.
(maybe_add_script): Delete.
(auto_load_objfile_script): Declare.
(script_not_found_warning_print): Delete.
(auto_load_info_scripts): Update prototype.
(auto_load_gdb_scripts_enabled): Declare.
* python/py-auto-load.c (gdbpy_auto_load_enabled): Renamed from
auto_load_python_scripts_enabled and made public.
(script_language_python): Delete, moved to python.c.
(gdbpy_script_language_defn): Delete.
(info_auto_load_python_scripts): Update to use
extension_language_python.
* breakpoint.c (condition_command): Replace call to
gdbpy_breakpoint_has_py_cond with call to get_breakpoint_cond_ext_lang.
(bpstat_check_breakpoint_conditions): Replace call to gdbpy_should_stop
with call to breakpoint_ext_lang_cond_says_stop.
* python/py-breakpoint.c (gdbpy_breakpoint_cond_says_stop): Renamed
from gdbpy_should_stop. Change result type to enum scr_bp_stop.
New arg slang. Return SCR_BP_STOP_UNSET if py_bp_object is NULL.
(gdbpy_breakpoint_has_cond): Renamed from gdbpy_breakpoint_has_py_cond.
New arg slang.
(local_setattro): Print name of extension language with existing
stop condition.
* valprint.c (val_print, value_print): Update to call
apply_ext_lang_val_pretty_printer.
* cp-valprint.c (cp_print_value): Update call to
apply_ext_lang_val_pretty_printer.
* python/py-prettyprint.c: Remove #ifdef HAVE_PYTHON.
(gdbpy_apply_val_pretty_printer): Renamed from
apply_val_pretty_printer. New arg extlang.
(!HAVE_PYTHON, apply_val_pretty_printer): Delete.
* cli/cli-cmds.c (source_script_from_stream): Rewrite to use
extension language API.
* cli/cli-script.c (execute_control_command): Update to call
eval_ext_lang_from_control_command.
* mi/mi-cmd-stack.c (mi_cmd_stack_list_frames): Update to use
enum ext_lang_bt_status values. Update call to
apply_ext_lang_frame_filter.
(mi_cmd_stack_list_locals): Ditto.
(mi_cmd_stack_list_args): Ditto.
(mi_cmd_stack_list_variables): Ditto.
* mi/mi-main.c: Delete #include "python/python-internal.h".
Add #include "extension.h".
(mi_cmd_list_features): Replace reference to python internal variable
gdb_python_initialized with call to ext_lang_initialized_p.
* stack.c (backtrace_command_1): Update to use enum ext_lang_bt_status.
Update to use enum ext_lang_frame_args. Update to call
apply_ext_lang_frame_filter.
* python/py-framefilter.c (extract_sym): Update to use enum
ext_lang_bt_status.
(extract_value, py_print_type, py_print_value): Ditto.
(py_print_single_arg, enumerate_args, enumerate_locals): Ditto.
(py_mi_print_variables, py_print_locals, py_print_args): Ditto.
(py_print_frame): Ditto.
(gdbpy_apply_frame_filter): Renamed from apply_frame_filter.
New arg extlang. Update to use enum ext_lang_bt_status.
* top.c (gdb_init): Delete #ifdef HAVE_PYTHON call to
finish_python_initialization. Replace with call to
finish_ext_lang_initialization.
* typeprint.c (do_free_global_table): Update to call
free_ext_lang_type_printers.
(create_global_typedef_table): Update to call
start_ext_lang_type_printers.
(find_global_typedef): Update to call apply_ext_lang_type_printers.
* typeprint.h (struct ext_lang_type_printers): Add forward decl.
(type_print_options): Change type of global_printers from "void *"
to "struct ext_lang_type_printers *".
* value.c (preserve_values): Update to call preserve_ext_lang_values.
* python/py-value.c: Remove #ifdef HAVE_PYTHON.
(gdbpy_preserve_values): Renamed from preserve_python_values.
New arg extlang.
(!HAVE_PYTHON, preserve_python_values): Delete.
* utils.c (quit_flag): Delete, moved to extension.c.
(clear_quit_flag, set_quit_flag, check_quit_flag): Delete, moved to
extension.c.
* eval.c: Delete #include "python/python.h".
* main.c: Delete #include "python/python.h".
* defs.h: Update comment.
testsuite/
* gdb.python/py-breakpoint.exp (test_bkpt_eval_funcs): Update expected
output.
* gdb.gdb/python-interrupts.exp: New file.
While doing something else, I found that those 2 places were incorrectly
declaring a "struct gdb_exception" without using the "volatile" keyword.
This commit fixes that.
2014-01-17 Sergio Durigan Junior <sergiodj@redhat.com>
* breakpoint.c (insert_bp_location): Add "volatile" keyword to "struct
gdb_exception" declaration.
* remote.c (getpkt_or_notif_sane): Likewise.
Although we can tell upfront whether a remote target supports target
side commands, we can only tell whether the target supports that in
combination with a given breakpoint kind (software, hardware,
watchpoints, etc.) when we go and try to insert such a breakpoint kind
the first time. It's not desirable to make remote_insert_breakpoint
simply return -1 in this case, because if the breakpoint was set in a
shared library, insert_bp_location will assume that the breakpoint
insertion failed because the library wasn't mapped in.
insert_bp_location already handles errors/exceptions thrown from the
target_insert_xxx methods, exactly so the backend can tell the user
the detailed reason the insertion of hw breakpoints failed. But, in
the case of software breakpoints, it discards the detailed error
message.
So the patch makes insert_bp_location use the error's message for SW
breakpoints too, and, introduces a NOT_SUPPORTED_ERROR error code so
that insert_bp_location doesn't confuse the error for failure due to a
shared library disappearing.
The result is:
(gdb) c
Warning:
Cannot insert breakpoint 2: Target doesn't support breakpoints that have target side commands.
2014-01-09 Pedro Alves <palves@redhat.com>
Hui Zhu <hui@codesourcery.com>
PR gdb/16101
* breakpoint.c (insert_bp_location): Rename hw_bp_err_string to
bp_err_string. Don't mark the location shlib_disabled if the
error thrown wasn't a generic or memory error. Catch errors
thrown while inserting breakpoints in overlayed code. Output
error message of software breakpoints.
* remote.c (remote_insert_breakpoint): If this breakpoint has
target-side commands but this stub doesn't support Z0 packets,
throw NOT_SUPPORTED_ERROR error.
* exceptions.h (enum errors) <NOT_SUPPORTED_ERROR>: New error.
* target.h (target_insert_breakpoint): Extend comment.
(target_insert_hw_breakpoint): Add comment.
Code rationale
==============
by: Gabriel Krisman Bertazi
This is a fix for bug 16297. The problem occurs when the user attempts
to catch any syscall 0 (such as syscall read on Linux/x86_64). GDB was
not able to catch the syscall and was missing the breakpoint.
Now, breakpoint_hit_catch_syscall returns immediately when it finds the
correct syscall number, avoiding a following check for the end of the
search vector, that returns a no hit if the syscall number was zero.
Testcase rationale
==================
by: Sergio Durigan Junior
This testcase is a little difficult to write. By doing a quick
inspection at the Linux source, one can see that, in many targets, the
syscall number 0 is restart_syscall, which is forbidden to be called
from userspace. Therefore, on many targets, there's just no way to test
this safely.
My decision was to take the simpler route and just adds the "read"
syscall on the default test. Its number on x86_64 is zero, which is
"good enough" since many people here do their tests on x86_64 anyway and
it is a popular architecture.
However, there was another little gotcha. When using "read" passing 0
as the third parameter (i.e., asking it to read 0 bytes), current libc
implementations could choose not to effectively call the syscall.
Therefore, the best solution was to create a temporary pipe, write 1
byte into it, and then read this byte from it.
gdb/ChangeLog
2013-12-19 Gabriel Krisman Bertazi <gabriel@krisman.be>
PR breakpoints/16297
* breakpoint.c (breakpoint_hit_catch_syscall): Return immediately
when expected syscall is hit.
gdb/testsuite/ChangeLog
2013-12-19 Sergio Durigan Junior <sergiodj@redhat.com>
PR breakpoints/16297
* gdb.base/catch-syscall.c (read_syscall, pipe_syscall)
(write_syscall): New variables.
(main): Create a pipe, write 1 byte in it, and read 1 byte from
it.
* gdb.base/catch-syscall.exp (all_syscalls): Include "pipe,
"write" and "read" syscalls.
(fill_all_syscalls_numbers): Improve the way to obtain syscalls
numbers.
The memory management of bp_location->target_info.conditions|tcommands
is currently a little fragile. If the target reports support for
target conditions or commands, and then target side breakpoint support
is disabled, or some error is thrown before remote_add_target_side_XXX
is called, we'll leak these lists. This patch makes us free these
lists when the locations are deleted, and also, just before recreating
the commands|conditions lists.
Tested on x86_64 Fedora 17, native and gdbserver.
gdb/
2013-11-29 Pedro Alves <palves@redhat.com>
* breakpoint.c (build_target_condition_list): Release previous
conditions.
(build_target_command_list): Release previous commands.
(bp_location_dtor): Release target conditions and commands.
* remote.c (remote_add_target_side_condition): Don't release
conditions.
(remote_add_target_side_commands): Don't release commands.
This removes gdb_string.h. This patch is purely mechanical. I
created it by running the two commands:
git rm common/gdb_string.h
perl -pi -e's/"gdb_string.h"/<string.h>/;' *.[chyl] */*.[chyl]
2013-11-18 Tom Tromey <tromey@redhat.com>
* common/gdb_string.h: Remove.
* aarch64-tdep.c: Use string.h, not gdb_string.h.
* ada-exp.y: Use string.h, not gdb_string.h.
* ada-lang.c: Use string.h, not gdb_string.h.
* ada-lex.l: Use string.h, not gdb_string.h.
* ada-typeprint.c: Use string.h, not gdb_string.h.
* ada-valprint.c: Use string.h, not gdb_string.h.
* aix-thread.c: Use string.h, not gdb_string.h.
* alpha-linux-tdep.c: Use string.h, not gdb_string.h.
* alpha-mdebug-tdep.c: Use string.h, not gdb_string.h.
* alpha-nat.c: Use string.h, not gdb_string.h.
* alpha-osf1-tdep.c: Use string.h, not gdb_string.h.
* alpha-tdep.c: Use string.h, not gdb_string.h.
* alphanbsd-tdep.c: Use string.h, not gdb_string.h.
* amd64-dicos-tdep.c: Use string.h, not gdb_string.h.
* amd64-linux-nat.c: Use string.h, not gdb_string.h.
* amd64-linux-tdep.c: Use string.h, not gdb_string.h.
* amd64-nat.c: Use string.h, not gdb_string.h.
* amd64-sol2-tdep.c: Use string.h, not gdb_string.h.
* amd64fbsd-tdep.c: Use string.h, not gdb_string.h.
* amd64obsd-tdep.c: Use string.h, not gdb_string.h.
* arch-utils.c: Use string.h, not gdb_string.h.
* arm-linux-nat.c: Use string.h, not gdb_string.h.
* arm-linux-tdep.c: Use string.h, not gdb_string.h.
* arm-tdep.c: Use string.h, not gdb_string.h.
* arm-wince-tdep.c: Use string.h, not gdb_string.h.
* armbsd-tdep.c: Use string.h, not gdb_string.h.
* armnbsd-nat.c: Use string.h, not gdb_string.h.
* armnbsd-tdep.c: Use string.h, not gdb_string.h.
* armobsd-tdep.c: Use string.h, not gdb_string.h.
* avr-tdep.c: Use string.h, not gdb_string.h.
* ax-gdb.c: Use string.h, not gdb_string.h.
* ax-general.c: Use string.h, not gdb_string.h.
* bcache.c: Use string.h, not gdb_string.h.
* bfin-tdep.c: Use string.h, not gdb_string.h.
* breakpoint.c: Use string.h, not gdb_string.h.
* build-id.c: Use string.h, not gdb_string.h.
* buildsym.c: Use string.h, not gdb_string.h.
* c-exp.y: Use string.h, not gdb_string.h.
* c-lang.c: Use string.h, not gdb_string.h.
* c-typeprint.c: Use string.h, not gdb_string.h.
* c-valprint.c: Use string.h, not gdb_string.h.
* charset.c: Use string.h, not gdb_string.h.
* cli-out.c: Use string.h, not gdb_string.h.
* cli/cli-cmds.c: Use string.h, not gdb_string.h.
* cli/cli-decode.c: Use string.h, not gdb_string.h.
* cli/cli-dump.c: Use string.h, not gdb_string.h.
* cli/cli-interp.c: Use string.h, not gdb_string.h.
* cli/cli-logging.c: Use string.h, not gdb_string.h.
* cli/cli-script.c: Use string.h, not gdb_string.h.
* cli/cli-setshow.c: Use string.h, not gdb_string.h.
* cli/cli-utils.c: Use string.h, not gdb_string.h.
* coffread.c: Use string.h, not gdb_string.h.
* common/common-utils.c: Use string.h, not gdb_string.h.
* common/filestuff.c: Use string.h, not gdb_string.h.
* common/linux-procfs.c: Use string.h, not gdb_string.h.
* common/linux-ptrace.c: Use string.h, not gdb_string.h.
* common/signals.c: Use string.h, not gdb_string.h.
* common/vec.h: Use string.h, not gdb_string.h.
* core-regset.c: Use string.h, not gdb_string.h.
* corefile.c: Use string.h, not gdb_string.h.
* corelow.c: Use string.h, not gdb_string.h.
* cp-abi.c: Use string.h, not gdb_string.h.
* cp-support.c: Use string.h, not gdb_string.h.
* cp-valprint.c: Use string.h, not gdb_string.h.
* cris-tdep.c: Use string.h, not gdb_string.h.
* d-lang.c: Use string.h, not gdb_string.h.
* dbxread.c: Use string.h, not gdb_string.h.
* dcache.c: Use string.h, not gdb_string.h.
* demangle.c: Use string.h, not gdb_string.h.
* dicos-tdep.c: Use string.h, not gdb_string.h.
* disasm.c: Use string.h, not gdb_string.h.
* doublest.c: Use string.h, not gdb_string.h.
* dsrec.c: Use string.h, not gdb_string.h.
* dummy-frame.c: Use string.h, not gdb_string.h.
* dwarf2-frame.c: Use string.h, not gdb_string.h.
* dwarf2loc.c: Use string.h, not gdb_string.h.
* dwarf2read.c: Use string.h, not gdb_string.h.
* elfread.c: Use string.h, not gdb_string.h.
* environ.c: Use string.h, not gdb_string.h.
* eval.c: Use string.h, not gdb_string.h.
* event-loop.c: Use string.h, not gdb_string.h.
* exceptions.c: Use string.h, not gdb_string.h.
* exec.c: Use string.h, not gdb_string.h.
* expprint.c: Use string.h, not gdb_string.h.
* f-exp.y: Use string.h, not gdb_string.h.
* f-lang.c: Use string.h, not gdb_string.h.
* f-typeprint.c: Use string.h, not gdb_string.h.
* f-valprint.c: Use string.h, not gdb_string.h.
* fbsd-nat.c: Use string.h, not gdb_string.h.
* findcmd.c: Use string.h, not gdb_string.h.
* findvar.c: Use string.h, not gdb_string.h.
* fork-child.c: Use string.h, not gdb_string.h.
* frame.c: Use string.h, not gdb_string.h.
* frv-linux-tdep.c: Use string.h, not gdb_string.h.
* frv-tdep.c: Use string.h, not gdb_string.h.
* gdb.c: Use string.h, not gdb_string.h.
* gdb_bfd.c: Use string.h, not gdb_string.h.
* gdbarch.c: Use string.h, not gdb_string.h.
* gdbtypes.c: Use string.h, not gdb_string.h.
* gnu-nat.c: Use string.h, not gdb_string.h.
* gnu-v2-abi.c: Use string.h, not gdb_string.h.
* gnu-v3-abi.c: Use string.h, not gdb_string.h.
* go-exp.y: Use string.h, not gdb_string.h.
* go-lang.c: Use string.h, not gdb_string.h.
* go32-nat.c: Use string.h, not gdb_string.h.
* hppa-hpux-tdep.c: Use string.h, not gdb_string.h.
* hppa-linux-nat.c: Use string.h, not gdb_string.h.
* hppanbsd-tdep.c: Use string.h, not gdb_string.h.
* hppaobsd-tdep.c: Use string.h, not gdb_string.h.
* i386-cygwin-tdep.c: Use string.h, not gdb_string.h.
* i386-dicos-tdep.c: Use string.h, not gdb_string.h.
* i386-linux-nat.c: Use string.h, not gdb_string.h.
* i386-linux-tdep.c: Use string.h, not gdb_string.h.
* i386-nto-tdep.c: Use string.h, not gdb_string.h.
* i386-sol2-tdep.c: Use string.h, not gdb_string.h.
* i386-tdep.c: Use string.h, not gdb_string.h.
* i386bsd-tdep.c: Use string.h, not gdb_string.h.
* i386gnu-nat.c: Use string.h, not gdb_string.h.
* i386nbsd-tdep.c: Use string.h, not gdb_string.h.
* i386obsd-tdep.c: Use string.h, not gdb_string.h.
* i387-tdep.c: Use string.h, not gdb_string.h.
* ia64-libunwind-tdep.c: Use string.h, not gdb_string.h.
* ia64-linux-nat.c: Use string.h, not gdb_string.h.
* inf-child.c: Use string.h, not gdb_string.h.
* inf-ptrace.c: Use string.h, not gdb_string.h.
* inf-ttrace.c: Use string.h, not gdb_string.h.
* infcall.c: Use string.h, not gdb_string.h.
* infcmd.c: Use string.h, not gdb_string.h.
* inflow.c: Use string.h, not gdb_string.h.
* infrun.c: Use string.h, not gdb_string.h.
* interps.c: Use string.h, not gdb_string.h.
* iq2000-tdep.c: Use string.h, not gdb_string.h.
* irix5-nat.c: Use string.h, not gdb_string.h.
* jv-exp.y: Use string.h, not gdb_string.h.
* jv-lang.c: Use string.h, not gdb_string.h.
* jv-typeprint.c: Use string.h, not gdb_string.h.
* jv-valprint.c: Use string.h, not gdb_string.h.
* language.c: Use string.h, not gdb_string.h.
* linux-fork.c: Use string.h, not gdb_string.h.
* linux-nat.c: Use string.h, not gdb_string.h.
* lm32-tdep.c: Use string.h, not gdb_string.h.
* m2-exp.y: Use string.h, not gdb_string.h.
* m2-typeprint.c: Use string.h, not gdb_string.h.
* m32c-tdep.c: Use string.h, not gdb_string.h.
* m32r-linux-nat.c: Use string.h, not gdb_string.h.
* m32r-linux-tdep.c: Use string.h, not gdb_string.h.
* m32r-rom.c: Use string.h, not gdb_string.h.
* m32r-tdep.c: Use string.h, not gdb_string.h.
* m68hc11-tdep.c: Use string.h, not gdb_string.h.
* m68k-tdep.c: Use string.h, not gdb_string.h.
* m68kbsd-tdep.c: Use string.h, not gdb_string.h.
* m68klinux-nat.c: Use string.h, not gdb_string.h.
* m68klinux-tdep.c: Use string.h, not gdb_string.h.
* m88k-tdep.c: Use string.h, not gdb_string.h.
* macrocmd.c: Use string.h, not gdb_string.h.
* main.c: Use string.h, not gdb_string.h.
* mdebugread.c: Use string.h, not gdb_string.h.
* mem-break.c: Use string.h, not gdb_string.h.
* memattr.c: Use string.h, not gdb_string.h.
* memory-map.c: Use string.h, not gdb_string.h.
* mep-tdep.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-break.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-disas.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-env.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-stack.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-var.c: Use string.h, not gdb_string.h.
* mi/mi-cmds.c: Use string.h, not gdb_string.h.
* mi/mi-console.c: Use string.h, not gdb_string.h.
* mi/mi-getopt.c: Use string.h, not gdb_string.h.
* mi/mi-interp.c: Use string.h, not gdb_string.h.
* mi/mi-main.c: Use string.h, not gdb_string.h.
* mi/mi-parse.c: Use string.h, not gdb_string.h.
* microblaze-rom.c: Use string.h, not gdb_string.h.
* microblaze-tdep.c: Use string.h, not gdb_string.h.
* mingw-hdep.c: Use string.h, not gdb_string.h.
* minidebug.c: Use string.h, not gdb_string.h.
* minsyms.c: Use string.h, not gdb_string.h.
* mips-irix-tdep.c: Use string.h, not gdb_string.h.
* mips-linux-tdep.c: Use string.h, not gdb_string.h.
* mips-tdep.c: Use string.h, not gdb_string.h.
* mips64obsd-tdep.c: Use string.h, not gdb_string.h.
* mipsnbsd-tdep.c: Use string.h, not gdb_string.h.
* mipsread.c: Use string.h, not gdb_string.h.
* mn10300-linux-tdep.c: Use string.h, not gdb_string.h.
* mn10300-tdep.c: Use string.h, not gdb_string.h.
* monitor.c: Use string.h, not gdb_string.h.
* moxie-tdep.c: Use string.h, not gdb_string.h.
* mt-tdep.c: Use string.h, not gdb_string.h.
* nbsd-tdep.c: Use string.h, not gdb_string.h.
* nios2-linux-tdep.c: Use string.h, not gdb_string.h.
* nto-procfs.c: Use string.h, not gdb_string.h.
* nto-tdep.c: Use string.h, not gdb_string.h.
* objc-lang.c: Use string.h, not gdb_string.h.
* objfiles.c: Use string.h, not gdb_string.h.
* opencl-lang.c: Use string.h, not gdb_string.h.
* osabi.c: Use string.h, not gdb_string.h.
* osdata.c: Use string.h, not gdb_string.h.
* p-exp.y: Use string.h, not gdb_string.h.
* p-lang.c: Use string.h, not gdb_string.h.
* p-typeprint.c: Use string.h, not gdb_string.h.
* parse.c: Use string.h, not gdb_string.h.
* posix-hdep.c: Use string.h, not gdb_string.h.
* ppc-linux-nat.c: Use string.h, not gdb_string.h.
* ppc-sysv-tdep.c: Use string.h, not gdb_string.h.
* ppcfbsd-tdep.c: Use string.h, not gdb_string.h.
* ppcnbsd-tdep.c: Use string.h, not gdb_string.h.
* ppcobsd-tdep.c: Use string.h, not gdb_string.h.
* printcmd.c: Use string.h, not gdb_string.h.
* procfs.c: Use string.h, not gdb_string.h.
* prologue-value.c: Use string.h, not gdb_string.h.
* python/py-auto-load.c: Use string.h, not gdb_string.h.
* python/py-gdb-readline.c: Use string.h, not gdb_string.h.
* ravenscar-thread.c: Use string.h, not gdb_string.h.
* regcache.c: Use string.h, not gdb_string.h.
* registry.c: Use string.h, not gdb_string.h.
* remote-fileio.c: Use string.h, not gdb_string.h.
* remote-m32r-sdi.c: Use string.h, not gdb_string.h.
* remote-mips.c: Use string.h, not gdb_string.h.
* remote-sim.c: Use string.h, not gdb_string.h.
* remote.c: Use string.h, not gdb_string.h.
* reverse.c: Use string.h, not gdb_string.h.
* rs6000-aix-tdep.c: Use string.h, not gdb_string.h.
* ser-base.c: Use string.h, not gdb_string.h.
* ser-go32.c: Use string.h, not gdb_string.h.
* ser-mingw.c: Use string.h, not gdb_string.h.
* ser-pipe.c: Use string.h, not gdb_string.h.
* ser-tcp.c: Use string.h, not gdb_string.h.
* ser-unix.c: Use string.h, not gdb_string.h.
* serial.c: Use string.h, not gdb_string.h.
* sh-tdep.c: Use string.h, not gdb_string.h.
* sh64-tdep.c: Use string.h, not gdb_string.h.
* shnbsd-tdep.c: Use string.h, not gdb_string.h.
* skip.c: Use string.h, not gdb_string.h.
* sol-thread.c: Use string.h, not gdb_string.h.
* solib-dsbt.c: Use string.h, not gdb_string.h.
* solib-frv.c: Use string.h, not gdb_string.h.
* solib-osf.c: Use string.h, not gdb_string.h.
* solib-spu.c: Use string.h, not gdb_string.h.
* solib-target.c: Use string.h, not gdb_string.h.
* solib.c: Use string.h, not gdb_string.h.
* somread.c: Use string.h, not gdb_string.h.
* source.c: Use string.h, not gdb_string.h.
* sparc-nat.c: Use string.h, not gdb_string.h.
* sparc-sol2-tdep.c: Use string.h, not gdb_string.h.
* sparc-tdep.c: Use string.h, not gdb_string.h.
* sparc64-tdep.c: Use string.h, not gdb_string.h.
* sparc64fbsd-tdep.c: Use string.h, not gdb_string.h.
* sparc64nbsd-tdep.c: Use string.h, not gdb_string.h.
* sparcnbsd-tdep.c: Use string.h, not gdb_string.h.
* spu-linux-nat.c: Use string.h, not gdb_string.h.
* spu-multiarch.c: Use string.h, not gdb_string.h.
* spu-tdep.c: Use string.h, not gdb_string.h.
* stabsread.c: Use string.h, not gdb_string.h.
* stack.c: Use string.h, not gdb_string.h.
* std-regs.c: Use string.h, not gdb_string.h.
* symfile.c: Use string.h, not gdb_string.h.
* symmisc.c: Use string.h, not gdb_string.h.
* symtab.c: Use string.h, not gdb_string.h.
* target.c: Use string.h, not gdb_string.h.
* thread.c: Use string.h, not gdb_string.h.
* tilegx-linux-nat.c: Use string.h, not gdb_string.h.
* tilegx-tdep.c: Use string.h, not gdb_string.h.
* top.c: Use string.h, not gdb_string.h.
* tracepoint.c: Use string.h, not gdb_string.h.
* tui/tui-command.c: Use string.h, not gdb_string.h.
* tui/tui-data.c: Use string.h, not gdb_string.h.
* tui/tui-disasm.c: Use string.h, not gdb_string.h.
* tui/tui-file.c: Use string.h, not gdb_string.h.
* tui/tui-layout.c: Use string.h, not gdb_string.h.
* tui/tui-out.c: Use string.h, not gdb_string.h.
* tui/tui-regs.c: Use string.h, not gdb_string.h.
* tui/tui-source.c: Use string.h, not gdb_string.h.
* tui/tui-stack.c: Use string.h, not gdb_string.h.
* tui/tui-win.c: Use string.h, not gdb_string.h.
* tui/tui-windata.c: Use string.h, not gdb_string.h.
* tui/tui-winsource.c: Use string.h, not gdb_string.h.
* typeprint.c: Use string.h, not gdb_string.h.
* ui-file.c: Use string.h, not gdb_string.h.
* ui-out.c: Use string.h, not gdb_string.h.
* user-regs.c: Use string.h, not gdb_string.h.
* utils.c: Use string.h, not gdb_string.h.
* v850-tdep.c: Use string.h, not gdb_string.h.
* valarith.c: Use string.h, not gdb_string.h.
* valops.c: Use string.h, not gdb_string.h.
* valprint.c: Use string.h, not gdb_string.h.
* value.c: Use string.h, not gdb_string.h.
* varobj.c: Use string.h, not gdb_string.h.
* vax-tdep.c: Use string.h, not gdb_string.h.
* vaxnbsd-tdep.c: Use string.h, not gdb_string.h.
* vaxobsd-tdep.c: Use string.h, not gdb_string.h.
* windows-nat.c: Use string.h, not gdb_string.h.
* xcoffread.c: Use string.h, not gdb_string.h.
* xml-support.c: Use string.h, not gdb_string.h.
* xstormy16-tdep.c: Use string.h, not gdb_string.h.
* xtensa-linux-nat.c: Use string.h, not gdb_string.h.
After the previous patch, there's actually no breakpoint type that
returns BPSTAT_SIGNAL_HIDE, so we can go back to having
bpstat_explains_signal return a boolean. The signal hiding actually
disappears.
gdb/
2013-11-14 Pedro Alves <palves@redhat.com>
* break-catch-sig.c (signal_catchpoint_explains_signal): Adjust to
return a boolean.
* breakpoint.c (bpstat_explains_signal): Adjust to return a
boolean.
(explains_signal_watchpoint, base_breakpoint_explains_signal):
Adjust to return a boolean.
* breakpoint.h (enum bpstat_signal_value): Delete.
(struct breakpoint_ops) <explains_signal>: New returns a boolean.
(bpstat_explains_signal): Likewise.
* infrun.c (handle_inferior_event) <random signal checks>:
bpstat_explains_signal now returns a boolean - adjust. No longer
consider hiding signals.
Looking at the current random signal checks:
if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
random_signal
= !((bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
GDB_SIGNAL_TRAP)
!= BPSTAT_SIGNAL_NO)
|| stopped_by_watchpoint
|| ecs->event_thread->control.trap_expected
|| (ecs->event_thread->control.step_range_end
&& (ecs->event_thread->control.step_resume_breakpoint
== NULL)));
else
{
enum bpstat_signal_value sval;
sval = bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
ecs->event_thread->suspend.stop_signal);
random_signal = (sval == BPSTAT_SIGNAL_NO);
if (sval == BPSTAT_SIGNAL_HIDE)
ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
}
We can observe:
- the stepping checks bit:
...
|| ecs->event_thread->control.trap_expected
|| (ecs->event_thread->control.step_range_end
&& (ecs->event_thread->control.step_resume_breakpoint
== NULL)));
...
is just like currently_stepping:
static int
currently_stepping (struct thread_info *tp)
{
return ((tp->control.step_range_end
&& tp->control.step_resume_breakpoint == NULL)
|| tp->control.trap_expected
|| bpstat_should_step ());
}
except it misses the bpstat_should_step check (***).
It's not really necessary to check bpstat_should_step in the
random signal tests, because software watchpoints always end up in
the bpstat list anyway, which means bpstat_explains_signal with
GDB_SIGNAL_TRAP always returns at least BPSSTAT_SIGNAL_HIDE, but I
think the code is clearer if we reuse currently_stepping.
*** - bpstat_should_step checks to see if there's any software
watchpoint in the breakpoint list, because we need to force the
target to single-step all the way, to evaluate the watchpoint's
value at each step.
- we never hide GDB_SIGNAL_TRAP, even if the bpstat returns
BPSTAT_SIGNAL_HIDE, which is actually the default for all
breakpoints. If we make the default be BPSTAT_SIGNAL_PASS, then
we can merge the two bpstat_explains_signal paths.
gdb/
2013-11-14 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_explains_signal) <Moribund locations>:
Return BPSTAT_SIGNAL_PASS instead of BPSTAT_SIGNAL_HIDE.
(explains_signal_watchpoint): Return BPSTAT_SIGNAL_PASS instead of
BPSTAT_SIGNAL_HIDE.
(base_breakpoint_explains_signal): Return BPSTAT_SIGNAL_PASS
instead of BPSTAT_SIGNAL_HIDE.
* infrun.c (handle_inferior_event): Rework random signal checks.
As discussed on the GDB ML[1], libc probes for longjmp were not being
loaded if a custom <arch>_get_longjmp_target function was not
implemented.
This is trivially fixed by moving the 'if (!gdbarch_get_longjmp_target_p
(gdbarch))' down, just bellow libc probe code and above the per-objfile
cache lookup.
While the condition could also be removed altogether with no
side-effects, it is in fact an optimization to avoid searching for
symbols if the arch doesn't provide support for get_longjmp_target().
This has been tested on PPC and PPC64.
[1] https://sourceware.org/ml/gdb/2013-10/msg00191.html
gdb/
2013-11-01 Tiago Stürmer Daitx <tdaitx@linux.vnet.ibm.com>
* breakpoint.c (create_longjmp_master_breakpoint): Allow libc
probe scan even when the arch provides no get_longjmp_target.
Pedro Alves
Yao Qi
Cordian A. Daniluk
Tom Tromey
Trevor Saunders
Keith Seitz
Doug Evans
Joel Brobecker
Antoine Tremblay
Simon Marchi
Luis Machado
Pierre Langlois
Martin Galvan
Gabriel Krisman Bertazi
Jan Kratochvil
Sergio Durigan Junior
Gary Benson
Jose E. Marchesi
Tom Tromey
Doug Evans
Maciej W. Rozycki
Patrick Palka
Yao Qi
Honggyu Kim
Tiago Stürmer Daitx