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
Tom Tromey
Trevor Saunders
Yao Qi
Keith Seitz
Doug Evans
Joel Brobecker
Antoine Tremblay
Simon Marchi
Luis Machado
Pierre Langlois
Martin Galvan
Gabriel Krisman Bertazi