This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
Using std::move forces an extra copy of the object. These changes fix
-Wpessimizing-move warnings from clang.
gdb/ChangeLog:
* ada-lang.c (create_excep_cond_exprs): Do not use 'std::move'.
* ax-gdb.c (agent_eval_command_one): Likewise.
(agent_eval_command_one): Likewise.
* breakpoint.c (parse_cond_to_aexpr): Likewise.
(parse_cmd_to_aexpr): Likewise.
* dtrace-probe.c (dtrace_process_dof_probe): Likewise.
* parse.c (parse_expression_for_completion): Likewise.
Now that we require C++11, use std::unique_ptr and std::move directly.
gdb/ChangeLog:
2016-11-15 Pedro Alves <palves@redhat.com>
* ada-lang.c (create_excep_cond_exprs): Use std::move instead of
gdb::move.
* break-catch-throw.c (handle_gnu_v3_exceptions): Use
std::unique_ptr instead of gdb::unique_ptr.
* breakpoint.c (watch_command_1): Use std::move instead of
gdb::move.
* cli/cli-dump.c (dump_memory_to_file, restore_binary_file): Use
std::unique_ptr instead of gdb::unique_ptr.
* dtrace-probe.c (dtrace_process_dof_probe): Use std::move instead
of gdb::move.
* elfread.c (elf_read_minimal_symbols): Use std::unique_ptr
instead of gdb::unique_ptr.
* mi/mi-main.c (mi_cmd_data_read_memory): Use std::unique_ptr
instead of gdb::unique_ptr.
* parse.c (parse_expression_for_completion): Use std::move instead
of gdb::move.
* printcmd.c (display_command): std::move instead of gdb::move.
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.
On x86-solaris 10, we noticed that starting a program would sometimes
cause the debugger to crash. For instance:
% gdb a
(gdb) break adainit
Breakpoint 1 at 0x8051f03
(gdb) run
Starting program: /[...]/a
[Thread debugging using libthread_db enabled]
zsh: 24398 segmentation fault (core dumped) /[...]/gdb a
The exception occurs in dtrace_process_dof_probe, while trying
to process each probe referenced by a DTRACE_DOF_SECT_TYPE_PROVIDER
DOF section from /lib/libc.so.1. For reference, the ELF section
in that shared library providing the DOF data has the following
characteristics:
Idx Name Size VMA LMA File off Algn
14 .SUNW_dof 0000109d 000b4398 000b4398 000b4398 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
The function dtrace_process_dof gets passed the contents of that
ELF section, which allows it to determine the location of the table
where all DOF sections are described. I dumped the contents of
each DOF section as seen by GDB, and it seemed to be plausible,
because the offset of each DOF section was pretty much equal to
the sum of the offset and size of the previous DOF section. Also,
the offset + sum of the last section corresponds to the size of
the .SUNW_dof section.
Things start to break down when processing one of the DOF sections
that has a type of DTRACE_DOF_SECT_TYPE_PROVIDER. It gets the contents
of this DOF section via:
struct dtrace_dof_provider *provider = (struct dtrace_dof_provider *)
DTRACE_DOF_PTR (dof, DOF_UINT (dof, section->dofs_offset));
Said more simply, the struct dtrace_dof_provider data is at
section->dofs_offset of the entire DOF contents. Given that
the contents of SECTION seemed to make sense, so far so good.
However, what SECTION tells us is that our DOF provider section
is 40 bytes long:
(gdb) print *section
$36 = {dofs_type = 15, dofs_align = 4, dofs_flags = 1,
dofs_entsize = 0, dofs_offset = 3264, dofs_size = 40}
^^^^^^^^^^^^^^
But on the other hand:
(gdb) p sizeof (struct dtrace_dof_provider)
$54 = 44
In other words GDB expected a bigger DOF section and when we try to
fetch the value of the last field of that DOF section (dofpv_prenoffs)...
eoffsets_s = DTRACE_DOF_SECT (dof,
DOF_UINT (dof, provider->dofpv_prenoffs));
... we end up reading data that actually belongs to another DOF
section, and therefore irrelevant. This in turn means that the value
of eofftab gets incorrectly set, since it depends on eoffsets_s:
eofftab = DTRACE_DOF_PTR (dof, DOF_UINT (dof, eoffsets_s->dofs_offset));
This invalid address quickly catches up to us when we pass it to
dtrace_process_dof_probe shortly after, where we crash because
we try to subscript it:
Program received signal SIGSEGV, Segmentation fault.
0x08155bba in dtrace_process_dof_probe ([...]) at [...]/dtrace-probe.c:378
378 = ((uint32_t *) eofftab)[...];
This patch fixes the issue by detecting provider DOF sections
that are smaller than expected, and discarding the DOF data.
gdb/ChangeLog:
* dtrace-probe.c (dtrace_process_dof): Ignore the objfile's DOF
data if a DTRACE_DOF_SECT_TYPE_PROVIDER section is found to be
smaller than expected.
GCC 4.4.7 generates the following warning:
| cc1: warnings being treated as errors
| dtrace-probe.c: In function ‘dtrace_process_dof_probe’:
| dtrace-probe.c:416: error: ‘expr’ may be used uninitialized in this function
| make[2]: *** [dtrace-probe.o] Error 1
Later versions (GCC 5) do a better job and don't generate the warning,
but it does not hurt to pre-initialize "expr" to NULL.
gdb/ChangeLog:
* dtrace-probe.c (dtrace_process_dof_probe): Initialize expr to NULL.
The debugger on Solaris has been broken since the introduction of
DTrace probe support:
(gdb) start
Temporary breakpoint 1 at 0x80593bc: file simple_main.adb, line 4.
Starting program: /[...]/simple_main
[Thread debugging using libthread_db enabled]
No definition of "mutex_t" in current context.
The problem occurs while trying to parse a probe's argument,
and the exception propagates all the way to the top. This patch
fixes the issue by containing the exception and falling back on
using the "long" builtin type if the argument's type could not
be determined.
Also, the parsing should be done using the C language parser.
gdb/ChangeLog:
* dtrace-probe.c (dtrace_process_dof_probe): Contain any
exception raised while parsing the probe arguments.
Force parsing to be done using the C language parser.
* expression.h (parse_expression_with_language): Declare.
* parse.c (parse_expression_with_language): New function.
In C++, we can't forward declare objects like in C. The compiler
complains about symbol redefinition. Most cases of this were fixed in
e36122e9, but dtrace probes introduced a new one meanwhile. This
patch fixes it the same way e36122e9 fixed the others.
gdb/
2015-02-27 Pedro Alves <palves@redhat.com>
* dtrace-probe.c (dtrace_probe_ops): Make extern.
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.
Joel Brobecker