When debugging on Windows with GDBserver, the debugger starts
failing after hitting a breakpoint. For instance:
(gdb) b foo
Breakpoint 1 at 0x40177e: file foo.adb, line 5.
(gdb) cont
Continuing.
Breakpoint 1, foo () at foo.adb:5
5 Put_Line ("Hello World."); -- STOP
(gdb) n
Program received signal SIGSEGV, Segmentation fault.
0x00401782 in foo () at foo.adb:5
5 Put_Line ("Hello World."); -- STOP
There are two issues:
1. While trying to re-insert a breakpoint that is still inserted
in memory, insert_bp_location wipes out the breakpoint location's
shadow_contents. As a consequence, we cannot restore the proper
instruction when removing the breakpoint anymore. That's why
the inferior's behavior changes when trying to resume after
the breakpoint was hit.
2. mem-break.c:default_memory_insert_breakpoint passes a breakpoint
location's shadow_contents as the buffer for a memory read.
This reveals a limitation of the various memory-read target
functions. This patch documents this limitation and adjust
the two calls that seem to hit that limitation.
gdb/ChangeLog:
* breakpoint.c (breakpoint_xfer_memory): Add assertion.
Update function description.
(insert_bp_location): Do not wipe bl->target_info out.
* mem-break.c: #include "gdb_string.h".
(default_memory_insert_breakpoint): Do not call target_read_memory
with a pointer to the breakpoint's shadow_contents buffer. Use
a local buffer instead.
* m32r-tdep.c (m32r_memory_insert_breakpoint): Ditto.
The 3 valid values for this setting are "auto", "host" and "target".
The help was advertising one of them to be "gdb" instead of "host".
gdb/ChangeLog:
* breakpoint.c (_initialize_breakpoint): Fix error in help of
"set breakpoint condition-evaluation" command.
Pedro Alves <palves@redhat.com>
PR breakpoints/13776:
* breakpoint.c (breakpoint_init_inferior): Delete step-resume
breakpoints.
(delete_longjmp_breakpoint_at_next_stop): New.
* breakpoint.h (delete_longjmp_breakpoint_at_next_stop): Declare.
* target.c (generic_mourn_inferior): Call mark_breakpoints_out
before deleting the inferior. Add comments.
* thread.c (clear_thread_inferior_resources): Don't delete lonjmp
breakpoints immediately, but only on next stop. Move that code
next to where we mark other breakpoints for deletion.
* remote.c (remote_supports_cond_breakpoints): New forward
declaration.
(remote_add_target_side_condition): New function.
(remote_insert_breakpoint): Add target-side breakpoint
conditional if supported.
(remote_insert_hw_breakpoint): Likewise.
(init_remote_ops): Set to_supports_evaluation_of_breakpoint_conditions
hook.
* target.c (update_current_target): Inherit
to_supports_evaluation_of_breakpoint_conditions.
Default to_supports_evaluation_of_breakpoint_conditions to return_zero.
* target.h (struct target_ops)
<to_supports_evaluation_of_breakpoint_conditions>: New field.
(target_supports_evaluation_of_breakpoint_conditions): New #define.
* breakpoint.c (get_first_locp_gte_addr): New forward declaration.
(condition_evaluation_both, condition_evaluation_auto,
condition_evaluation_host, condition_evaluation_target,
condition_evaluation_enums, condition_evaluation_mode_1,
condition_evaluation_mode): New static globals.
(translate_condition_evaluation_mode): New function.
(breakpoint_condition_evaluation_mode): New function.
(gdb_evaluates_breakpoint_condition_p): New function.
(ALL_BP_LOCATIONS_AT_ADDR): New helper macro.
(mark_breakpoint_modified): New function.
(mark_breakpoint_location_modified): New function.
(set_condition_evaluation_mode): New function.
(show_condition_evaluation_mode): New function.
(bp_location_compare_addrs): New function.
(get_first_location_gte_addr): New helper function.
(set_breakpoint_condition): Free condition bytecode if locations
has become unconditional. Call mark_breakpoint_modified (...).
(condition_command): Call update_global_location_list (1) for
breakpoints.
(breakpoint_xfer_memory): Use is_breakpoint (...).
(is_breakpoint): New function.
(parse_cond_to_aexpr): New function.
(build_target_condition_list): New function.
(insert_bp_location): Handle target-side conditional
breakpoints and call build_target_condition_list (...).
(update_inserted_breakpoint_locations): New function.
(insert_breakpoint_locations): Handle target-side conditional
breakpoints.
(bpstat_check_breakpoint_conditions): Add comment.
(bp_condition_evaluator): New function.
(bp_location_condition_evaluator): New function.
(print_breakpoint_location): Print information on where the condition
will be evaluated.
(print_one_breakpoint_location): Likewise.
(init_bp_location): Call mark_breakpoint_location_modified (...) for
breakpoint location.
(force_breakpoint_reinsertion): New functions.
(update_global_location_list): Handle target-side breakpoint
conditions.
Reinsert locations that are already inserted if conditions have
changed.
(bp_location_dtor): Free agent expression bytecode.
(disable_breakpoint): Call mark_breakpoint_modified (...).
Call update_global_location_list (...) with parameter 1 for breakpoints.
(disable_command): Call mark_breakpoint_location_modified (...).
Call update_global_location_list (...) with parameter 1 for breakpoints.
(enable_breakpoint_disp): Call mark_breakpoint_modified (...).
(enable_command): mark_breakpoint_location_modified (...).
(_initialize_breakpoint): Update documentation and add
condition-evaluation breakpoint subcommand.
* breakpoint.h: Include ax.h.
(condition_list): New data structure.
(condition_status): New enum.
(bp_target_info) <cond_list>: New field.
(bp_location) <condition_changed, cond_bytecode>: New fields.
(is_breakpoint): New prototype.
* solib.c (update_solib_list): Update the program space's
added_solibs and deleted_solibs fields.
* progspace.h (struct program_space) <added_solibs,
deleted_solibs>: New fields.
(clear_program_space_solib_cache): Declare.
* progspace.c (release_program_space): Call
clear_program_space_solib_cache.
(clear_program_space_solib_cache): New function.
* infrun.c (handle_inferior_event) <TARGET_WAITKIND_LOADED>: Call
bpstat_stop_status. Use handle_solib_event.
* breakpoint.c: Include gdb_regex.h.
(print_solib_event): New function.
(bpstat_print): Use print_solib_event.
(bpstat_stop_status): Add special case for bp_shlib_event.
(handle_solib_event): New function.
(bpstat_what): Use handle_solib_event.
(struct solib_catchpoint): New.
(dtor_catch_solib, insert_catch_solib, remove_catch_solib)
(breakpoint_hit_catch_solib, check_status_catch_solib)
(print_it_catch_solib, print_one_catch_solib)
(print_mention_catch_solib, print_recreate_catch_solib): New
functions.
(catch_solib_breakpoint_ops): New global.
(catch_load_or_unload, catch_load_command_1)
(catch_unload_command_1): New functions.
(internal_bkpt_check_status): Add special case for
bp_shlib_event.
(internal_bkpt_print_it): Use print_solib_event.
(initialize_breakpoint_ops): Initialize
catch_solib_breakpoint_ops.
(_initialize_breakpoint): Register "catch load" and "catch
unload".
* breakpoint.h (handle_solib_event): Declare.
* NEWS: Add entry for "catch load" and "catch unload".
gdb/doc
* gdb.texinfo (Set Catchpoints): Document "catch load" and "catch
unload".
(Files): Mention new catch commands.
(GDB/MI Async Records): Likewise.
gdb/testsuite
* lib/mi-support.exp (mi_expect_stop): Add special case for
solib-event.
* gdb.base/catch-load-so.c: New file.
* gdb.base/catch-load.exp: New file.
* gdb.base/catch-load.c: New file.
* gdb.base/break-interp.exp (reach_1): Update regexp.
* breakpoint.c (breakpoint_hit_catch_fork)
(breakpoint_hit_catch_vfork, breakpoint_hit_catch_syscall)
(breakpoint_hit_catch_exec): Make use of the `ws' argument.
* infrun.c (inferior_has_forked, inferior_has_vforked)
(inferior_has_execd, inferior_has_called_syscall): Delete.
(handle_syscall_event): Get syscall_number from the execution
control state's wait status.
(wait_for_inferior): Don't clear syscall_number.
* breakpoint.c (bpstat_stop_status): Moving clearing print_it
outside `bs->stop' block.
(bpstat_what): Rework bp_shlib_event handling.
(internal_bkpt_check_status): If the breakpoint is a
bp_shlib_event, then set bs->stop and bs->print if
stop_on_solib_events is set.
Fix watchpoints to be specific for each inferior.
* breakpoint.c (watchpoint_in_thread_scope): Verify also
current_program_space.
* i386-nat.c (i386_inferior_data_cleanup): New.
(i386_inferior_data_get): Replace variable inf_data_local by an
inferior_data call.
(i386_use_watchpoints): Initialize i386_inferior_data.
* linux-nat.c (linux_nat_iterate_watchpoint_lwps): Use INFERIOR_PTID
specific iterate_over_lwps.
gdb/testsuite/
Fix watchpoints to be specific for each inferior.
* gdb.multi/watchpoint-multi.c: New file.
* gdb.multi/watchpoint-multi.exp: New file.
* NEWS: Add item.
* symtab.h (compare_filenames_for_search): Declare.
* symtab.c (compare_filenames_for_search): New function.
(iterate_over_some_symtabs): Use it.
* symfile.h (struct quick_symbol_functions)
<map_symtabs_matching_filename>: Change spec.
* psymtab.c (partial_map_symtabs_matching_filename): Use
compare_filenames_for_search. Update for new spec.
* dwarf2read.c (dw2_map_symtabs_matching_filename): Use
compare_filenames_for_search. Update for new spec.
* breakpoint.c (clear_command): Use compare_filenames_for_search.
gdb/doc
* gdb.texinfo (Specify Location): Document relative file name
handling.
gdb/testsuite
* gdb.linespec/linespec.exp: Change some tests to use $decimal.
Add tests for relative directory.
* breakpoint.c (create_sals_from_address_default): New function.
(create_breakpoints_sal_default): Likewise.
(decode_linespec_default): Likewise.
(is_marker_spec): Removed.
(strace_marker_p): New function.
(init_breakpoint_sal): Using `strace_marker_p' instead of
`is_marker_spec'.
(create_breakpoint): Call method `create_sals_from_address' from
breakpoint_ops, replacing code that created SALs conditionally
on the type of the breakpoint. Call method `create_breakpoints_sal',
replacing code that created breakpoints conditionally on the type
wanted.
(base_breakpoint_create_sals_from_address): New function.
(base_breakpoint_create_breakpoints_sal): Likewise.
(base_breakpoint_decode_linespec): Likewise.
(base_breakpoint_ops): Add methods
`base_breakpoint_create_sals_from_address',
`base_breakpoint_create_breakpoints_sal' and
`base_breakpoint_decode_linespec'.
(bkpt_create_sals_from_address): New function.
(bkpt_create_breakpoints_sal): Likewise.
(bkpt_decode_linespec): Likewise.
(tracepoint_create_sals_from_address): Likewise.
(tracepoint_create_breakpoints_sal): Likewise.
(tracepoint_decode_linespec): Likewise.
(strace_marker_create_sals_from_address): Likewise.
(strace_marker_create_breakpoints_sal): Likewise.
(strace_marker_decode_linespec): Likewise.
(strace_marker_breakpoint_ops): New variable.
(addr_string_to_sals): Remove `marker_spec'. Call method
`decode_linespec' from breakpoint_ops, replacing code that decoded
an address string into a SAL. Use `strace_marker_p' instead of
`marker_spec'.
(strace_command): Decide whether we are dealing with a static
tracepoint with marker or not. Use the appropriate breakpoint_ops.
(initialize_breakpoint_ops): Initialize new fields of breakpoint_ops.
* breakpoint.h (linespec_result, linespec_sals): New forward
declarations.
(breakpoint_ops) <create_sals_from_address>,
<create_breakpoints_sal>, <decode_linespec>: New methods.
* Makefile.in (SUBDIR_PYTHON_OBS): Add py-finishbreakpoint.o.
(SUBDIR_PYTHON_SRCS): Add python/py-finishbreakpoint.c.
Add build rule for this file.
* infcmd.c (print_return_value): Split to create get_return_value.
(get_return_value): New function based on print_return_value. Handle
case where stop_registers are not set.
* inferior.h (get_return_value): New prototype.
* python/py-breakpoint.c (bppy_pending_object): Make non-static.
(gdbpy_breakpoint_created): Set is_py_finish_bp is necessary.
(struct breakpoint_object): Move to python-internal.h
(BPPY_REQUIRE_VALID): Likewise.
(BPPY_SET_REQUIRE_VALID): Likewise.
(gdbpy_breakpoint_created): Initialize is_finish_bp.
(gdbpy_should_stop): Add pre/post hooks before/after calling stop
method.
* python/python-internal.h (breakpoint_object_type): Add as extern.
(bppy_pending_object): Likewise.
(typedef struct breakpoint_object) Removed.
(struct breakpoint_object): Moved from py-breakpoint.c.
Add field is_finish_bp.
(BPPY_REQUIRE_VALID): Moved from py-breakpoint.c.
(BPPY_SET_REQUIRE_VALID): Likewise.
(frame_object_to_frame_info): New prototype.
(gdbpy_initialize_finishbreakpoints): New prototype.
(bpfinishpy_is_finish_bp): Likewise.
(bpfinishpy_pre_stop_hook): Likewise.
(bpfinishpy_post_stop_hook): Likewise.
* python/py-finishbreakpoint.c: New file.
* python/py-frame.c(frame_object_to_frame_info): Make non-static and
accept PyObject instead of frame_object.
(frapy_is_valid): Don't cast to frame_object.
(frapy_name): Likewise.
(frapy_type): Likewise.
(frapy_unwind_stop_reason): Likewise.
(frapy_pc): Likewise.
(frapy_block): Likewise.
(frapy_function): Likewise.
(frapy_older): Likewise.
(frapy_newer): Likewise.
(frapy_find_sal): Likewise.
(frapy_read_var): Likewise.
(frapy_select): Likewise.
* python/python.c (gdbpy_is_stopped_at_finish_bp): New noop function.
(_initialize_python): Add gdbpy_initialize_finishbreakpoints.
* python/python.h: Include breakpoint.h
(gdbpy_is_stopped_at_finish_bp): New prototype.
doc/
* gdb.texinfo (Finish Breakpoints in Python): New subsection.
(Python API): Add menu entry for Finish Breakpoints.
testsuite/
* Makefile.in (EXECUTABLES): Add py-finish-breakpoint and
py-finish-breakpoint2
(MISCALLANEOUS): Add py-events-shlib.so and py-events-shlib-nodebug.so
* gdb.python/py-breakpoint.exp (mult_line): Define and use variable
instead of line number.
* gdb.python/py-finish-breakpoint.c: New file.
* gdb.python/py-finish-breakpoint.exp: New file.
* gdb.python/py-finish-breakpoint.py: New file.
* gdb.python/py-finish-breakpoint2.cc: New file.
* gdb.python/py-finish-breakpoint2.exp: New file.
* gdb.python/py-finish-breakpoint2.py: New file.
* breakpoint.h (struct tracepoint): New field traceframe_usage.
* breakpoint.c (print_one_breakpoint_location): Identify
tracepoints as such when reporting hit counts, report
trace buffer usage.
(create_tracepoint_from_upload): Copy status info.
* tracepoint.h (struct trace_status): Rename error_desc to stop_desc,
add fields user_name, notes, start_time, stop_time.
(struct uploaded_tp): Add fields hit_count, traceframe_usage.
* tracepoint.c (trace_user): New global.
(trace_notes): New global.
(trace_stop_notes): New global.
(start_tracing): Add argument and trace note handling.
(stop_tracing): Ditto.
(trace_start_command): Add notes argument.
(trace_stop_command): Ditto.
(trace_status_command): Report additional status info.
(trace_status_mi): Similarly.
(trace_save): Update, record tracepoint status.
(set_disconnected_tracing): Call target method directly.
(send_disconnected_tracing_value): Remove.
(set_trace_user): New function.
(set_trace_notes): New function.
(set_trace_stop_notes): New function.
(parse_trace_status): Handle additional status.
(parse_tracepoint_status): New function.
(parse_tracepoint_definition): Call it.
(tfile_get_tracepoint_status): New function.
(init_tfile_ops): Use it.
(_initialize_tracepoint): Add new setshows.
* target.h (struct target_ops): New methods to_get_tracepoint_status
and to_set_trace_notes.
(target_get_tracepoint_status): New macro.
(target_set_trace_notes): New macro.
* target.c (update_current_target): Add new methods.
* remote.c (remote_get_tracepoint_status): New function.
(remote_set_trace_notes): New function.
(init_remote_ops): Add them.
* mi/mi-main.c (mi_cmd_trace_start): Add argument to call.
(mi_cmd_trace_stop): Ditto.
* tracepoint.c (struct tracepoint): New field traceframe_usage.
(tracing_start_time): New global.
(tracing_stop_time): New global.
(tracing_user_name): New global.
(tracing_notes): New global.
(tracing_stop_note): New global.
(cmd_qtstart): Set traceframe_usage, start_time.
(stop_tracing): Set stop_time.
(cmd_qtstatus): Report additional status.
(cmd_qtp): New function.
(handle_tracepoint_query): Call it.
(cmd_qtnotes): New function.
(handle_tracepoint_general_set): Call it.
(get_timestamp): Rename from tsv_get_timestamp.
* gdb.texinfo (Starting and Stopping Trace Experiments): Document
note-related options and variables.
(Tracepoint Packets): Document packet changes.
* gdb.trace/tstatus.exp: New.
* gdb.trace/actions.c: Include string.h.
