In struct perf_event_mmap_page there are new fields data_size and data_offset
that give the location of the perf_event data buffer relative to the mmap
page. Use them if they are present.
gdb/
* nat/linux-btrace.c (linux_enable_bts): Check for
PERF_ATTR_SIZE_VER5.
Check for data_offset and data_size fields. Use them.
Adds a new command "record btrace pt" to configure the kernel to use
Intel(R) Processor Trace instead of Branch Trace Strore.
The "record btrace" command chooses the tracing format automatically.
Intel(R) Processor Trace support requires Linux 4.1 and libipt.
gdb/
* NEWS: Announce new commands "record btrace pt" and "record pt".
Announce new options "set|show record btrace pt buffer-size".
* btrace.c: Include "rsp-low.h".
Include "inttypes.h".
(btrace_add_pc): Add forward declaration.
(pt_reclassify_insn, ftrace_add_pt, btrace_pt_readmem_callback)
(pt_translate_cpu_vendor, btrace_finalize_ftrace_pt)
(btrace_compute_ftrace_pt): New.
(btrace_compute_ftrace): Support BTRACE_FORMAT_PT.
(check_xml_btrace_version): Update version check.
(parse_xml_raw, parse_xml_btrace_pt_config_cpu)
(parse_xml_btrace_pt_raw, parse_xml_btrace_pt)
(btrace_pt_config_cpu_attributes, btrace_pt_config_children)
(btrace_pt_children): New.
(btrace_children): Add support for "pt".
(parse_xml_btrace_conf_pt, btrace_conf_pt_attributes): New.
(btrace_conf_children): Add support for "pt".
* btrace.h: Include "intel-pt.h".
(btrace_pt_error): New.
* common/btrace-common.c (btrace_format_string, btrace_data_fini)
(btrace_data_empty): Support BTRACE_FORMAT_PT.
* common/btrace-common.h (btrace_format): Add BTRACE_FORMAT_PT.
(struct btrace_config_pt): New.
(struct btrace_config)<pt>: New.
(struct btrace_data_pt_config, struct btrace_data_pt): New.
(struct btrace_data)<pt>: New.
* features/btrace-conf.dtd (btrace-conf)<pt>: New.
(pt): New.
* features/btrace.dtd (btrace)<pt>: New.
(pt, pt-config, cpu): New.
* nat/linux-btrace.c (perf_event_read, perf_event_read_all)
(perf_event_pt_event_type, kernel_supports_pt)
(linux_supports_pt): New.
(linux_supports_btrace): Support BTRACE_FORMAT_PT.
(linux_enable_bts): Free tinfo on error.
(linux_enable_pt): New.
(linux_enable_btrace): Support BTRACE_FORMAT_PT.
(linux_disable_pt): New.
(linux_disable_btrace): Support BTRACE_FORMAT_PT.
(linux_fill_btrace_pt_config, linux_read_pt): New.
(linux_read_btrace): Support BTRACE_FORMAT_PT.
* nat/linux-btrace.h (struct btrace_tinfo_pt): New.
(struct btrace_target_info)<pt>: New.
* record-btrace.c (set_record_btrace_pt_cmdlist)
(show_record_btrace_pt_cmdlist): New.
(record_btrace_print_pt_conf): New.
(record_btrace_print_conf): Support BTRACE_FORMAT_PT.
(btrace_ui_out_decode_error): Support BTRACE_FORMAT_PT.
(cmd_record_btrace_pt_start): New.
(cmd_record_btrace_start): Support BTRACE_FORMAT_PT.
(cmd_set_record_btrace_pt, cmd_show_record_btrace_pt): New.
(_initialize_record_btrace): Add new commands.
* remote.c (PACKET_Qbtrace_pt, PACKET_Qbtrace_conf_pt_size): New.
(remote_protocol_features): Add "Qbtrace:pt".
Add "Qbtrace-conf:pt:size".
(remote_supports_btrace): Support BTRACE_FORMAT_PT.
(btrace_sync_conf): Support PACKET_Qbtrace_conf_pt_size.
(remote_enable_btrace): Support BTRACE_FORMAT_PT.
(_initialize_remote): Add new commands.
gdbserver/
* linux-low.c: Include "rsp-low.h"
(linux_low_encode_pt_config, linux_low_encode_raw): New.
(linux_low_read_btrace): Support BTRACE_FORMAT_PT.
(linux_low_btrace_conf): Support BTRACE_FORMAT_PT.
(handle_btrace_enable_pt): New.
(handle_btrace_general_set): Support "pt".
(handle_btrace_conf_general_set): Support "pt:size".
doc/
* gdb.texinfo (Process Record and Replay): Spell out that variables
and registers are not available during btrace replay.
Describe the new "record btrace pt" command.
Describe the new "set|show record btrace pt buffer-size" options.
(General Query Packets): Describe the new Qbtrace:pt and
Qbtrace-conf:pt:size packets.
Expand "bts" to "Branch Trace Store".
Update the branch trace DTD.
Check for libipt, an Intel(R) Processor Trace decoder library. The sources
can be found on github at:
https://github.com/01org/processor-trace
gdb/
* configure.ac: Check for libipt
* configure: Regenerate.
* config.in: Regenerate.
* Makefile.in (LIBIPT): New.
(CLIBS): Add $LIBIPT.
* NEWS: document new configure options
It was found that from
(gdb) set debug compile 1
(gdb) compile code 1
[...]
allocated 0x7f bytes at 0x7ffff7ff9000 prot 5
allocated 0x38 bytes at 0x7ffff7ff8000 prot 1
lookup undefined ELF symbol "_GLOBAL_OFFSET_TABLE_"
allocated 0x10 bytes at 0x7ffff7ff7000 for registers
(gdb) _
the message 'lookup undefined ELF symbol' looks as an error to people,
including to myself once.
Change it to:
allocated 0x7f bytes at 0x7ffff7ff9000 prot 5
allocated 0x38 bytes at 0x7ffff7ff8000 prot 1
ELF symbol "_GLOBAL_OFFSET_TABLE_" relocated to zero
allocated 0x10 bytes at 0x7ffff7ff7000 for registers
(gdb) _
gdb/ChangeLog
2015-07-02 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile-object-load.c (compile_object_load): Replace debug
message "lookup undefined ELF symbol" by 3 more specific messages.
For the Renesas rl78 architecture, associate a flags type with the PSW
register. This will cause symbolic flags to be printed when using
the "info registers" command.
gdb/ChangeLog:
* rl78-tdep.c (struct gdbarch_tdep): Add new field, rl78_psw_type.
(rl78_register_type): Add case for RL78_PSW_REGNUM.
(rl78_gdbarch_init): Initialize rl78_psw_type.
When I replaced TUI's frame_changed hook to fix PR tui/13378 I assumed
that there's no reason to refresh register information following a call
to "up", "down" or "frame". This assumption was made to fix the problem
of refreshing frame information twice following a sync-execution normal
stop (once in tui_normal_stop and then in tui_before_prompt) -- the
second refresh removing any highlights made by the first.
I was wrong about that -- GDB's snapshot of register information is
per-frame, and when the frame changes, registers do too (most
prominently the %rip and %rsp registers). So e.g. GDB 7.8 would
highlight such register changes after invoking "up", "down" or "frame",
and current GDB does not.
To fix this regression, this patch adds another (sufficient) condition
for refreshing register information: in
tui_refresh_frame_and_register_information, always refresh register
information if frame information has changed. This makes register
information get refreshed following a call to "up", "down" or "frame"
while still avoiding the "double refresh" issue following a normal stop.
This condition may seem to obsolete the existing registers_too_p
parameter, but it does not: following a normal stop, it is possible that
registers may have changed while frame information had not. We could be
on the exact same PC with different register values. The new condition
would not catch such a case, but the registers_too_p condition will. So
both conditions seem necessary (and either one is sufficient).
gdb/ChangeLog:
* tui/tui-hooks.c (tui_refresh_frame_and_register_information):
Update commentary. Always refresh the registers when frame
information has changed.
* tui/tui-stack.c (tui_show_frame_info): Update commentary.
Change return type to int. Return 1 if frame information has
changed, 1 otherwise.
(tui_before_prompt): Update commentary.
* tui/tui-stack.h (tui_show_frame_info): Change return type to
int.
As these characters don't need to be escaped for strings
wrapped inside {} braces, we can remove the unneeded backslashes.
gdb/testsuite/ChangeLog:
* lib/gdb.exp (test_class_help): Remove the unneeded escaping of
'[' and ']' characters.
The select_frame hook is used by TUI to update TUI's frame and register
information following changes to the selected frame. The problem with
this hook is that it gets called after every single frame change, even
if the frame change is only temporary or internal. This is the primary
cause of flickering and slowdown when running the inferior under TUI
with conditional breakpoints set. Internal GDB events are the source of
many calls to select_frame and these internal events are triggered
frequently, especially when a few conditional breakpoints are set.
This patch removes the select_frame hook altogether and instead makes
the frame and register information get updated in two key places (using
observers): after an inferior stops, and right before displaying a
prompt. The latter hook covers the case when frame information must be
updated following a call to "up", "down" or "frame", and the former
covers the case when frame and register information must be updated
after a call to "continue", "step", etc. or after the inferior stops in
async execution mode. Together these hooks should cover all the cases
when frame information ought to be refreshed (and when the relevant
windows ought to be subsequently updated).
The print_frame_info_listing hook is also effectively obsolete now, but
it still must be set while the TUI is active because its caller
print_frame_info will otherwise assume that the CLI is active, and will
print the frame informaion accordingly. So this patch also sets the
print_frame_info_listing hook to a dummy callback, in lieu of outright
removing it yet.
Effectively, with this patch, frame/PC changes that do not immediately
precede an inferior-stop event or a prompt display event no longer cause
TUI's frame and register information to be updated.
And as a result of this change and of the previous change to
tui_show_frame_info, the TUI is much more disciplined about updating the
screen, and so the flicker as described in the PR is totally gone.
gdb/ChangeLog:
PR tui/13378
* frame.c (select_frame): Remove reference to
deprecated_selected_frame_level_changed_hook.
* frame.h (deprecated_selected_frame_level_changed_hook): Remove
declaration.
* stack.c (deprecated_selected_frame_level_changed_hook):
Likewise.
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook):
Rename to ...
(tui_refresh_frame_and_register_information): ... this. Bail
out if there is no stack. Don't update register information
unless registers_too_p is true.
(tui_print_frame_info_listing_hook): Rename to ...
(tui_dummy_print_frame_info_listing_hook): ... this.
(tui_before_prompt): New function.
(tui_normal_stop): New function.
(tui_before_prompt_observer): New observer.
(tui_normal_stop_observer): New observer.
(tui_install_hooks): Set
deprecated_print_frame_info_listing_hook to
tui_dummy_print_frame_info_listing_hook. Register
tui_before_prompt_observer to call tui_before_prompt and
tui_normal_stop_observer to call tui_normal_stop. Remove
reference to deprecated_selected_frame_level_changed_hook.
(tui_remove_hooks): Detach and unset tui_before_prompt_observer
and tui_normal_stop_observer. Remove reference to
deprecated_selected_frame_level_changed_hook.
tui_show_frame_info is responsible for updating the visible windows
following a change in frame information (that being the currently
selected frame, PC, line number, etc). Currently it always redraws and
refreshes each window even if frame information has not changed. This
behavior is inefficient and helps contribute to the occassional
flickering of the TUI as described in the mentioned PR.
This patch makes tui_show_frame_info refresh the windows only if frame
information has changed. Determining whether frame information has
changed is done indirectly by determining whether the locator has
changed. This approach is convenient and yet sensible because the
locator contains all the relevant info we need to check anyway: the
current PC, the line number, the name of the executable and the name of
the current function. Probably only the PC is really necessary to
check, but it doesn't hurt to check every field.
Effectively, with this patch, consecutive calls to select_frame with the
same frame/PC no longer cause TUI's frame information to be updated
multiple times.
gdb/ChangeLog:
PR tui/13378
* tui/tui-stack.c (tui_set_locator_info): Change prototype to
return an int instead of void. Return whether the locator
window has changed.
(tui_show_frame_info): If the locator info has not changed, then
bail out early to avoid refreshing the windows.
The call to tui_alloc_content in tui_set_locator_info passes
locator->type as the type of the window whose content is being
allocated. This may seem correct but it's actually not because when
this code path actually get executed locator->type has not yet been to
set LOCATOR_WIN so it defaults to 0 i.e. SRC_WIN. Thus we allocate the
content of the locator window as if it was the source window. This
oversight turns out not to be a big deal in practice but the patch that
follows depends on the locator's proc_name and full_name arrays to be
initialized to the empty string which is done by tui_alloc_content if
we pass to it LOCATOR_WIN.
This patch fixes this bug by explicitly passing LOCATOR_WIN to
tui_alloc_content.
gdb/ChangeLog:
* tui/tui-stack.c (tui_set_locator_info): Explicitly pass
LOCATOR_WIN to tui_alloc_content.
This patch fixes PR 18605 which is about incorrectly decoding media
instructions in software single step.
gdb:
2015-06-30 Yao Qi <yao.qi@linaro.org>
PR tdep/18605
* arm-tdep.c (arm_get_next_pc_raw): Break for media
instructions.
This change turns on dwarf2 unwinding in rx-tdep.c. I found it
necessary to add rx_dwarf_reg_to_regnum in order to cause PC to be
mapped correctly.
gdb/ChangeLog:
* rx-tdep.c (RX_PSW_REGNUM): New enum constant.
(rx_dwarf_reg_to_regnum): New function.
(rx_gdbarch_init): Register rx_dwarf_reg_to_regnum. Use dwarf2
unwinding.
The crash reason is that the insn to be moved to stub may be a
relocation spot, so instead of placing the origin insn (that is insn
before-relocation) to the stub, I have to place the relocated one.
Note the relocation involved is non-pc-relative, so it is safe to move
the relocated insn.
gold/ChangeLog:
2015-06-29 Han Shen <shenhan@google.com>
* AArch64.cc (Erratum_stub::Insn_utilities): New typedef.
(Erratum_stub::update_erratum_insn): New method.
(Stub_table::relocate_stubs): Modified to place relocated insn.
(AArch64_relobj::fix_errata): Modified gold_assert.
Refs:
https://sourceware.org/ml/gdb/2015-03/msg00024.htmlhttps://sourceware.org/ml/gdb/2015-06/msg00005.html
On GNU/Linux, if an infcall spawns a thread, that thread ends up with
stuck running state. This happens because:
- when linux-nat.c detects a new thread, it marks them as running,
and does not report anything to the core.
- we skip finish_thread_state when the thread that is running the
infcall stops.
As result, that new thread ends up with stuck "running" state, even
though it really is stopped.
On Windows, _all_ threads end up stuck in running state, not just the
one that was spawned. That happens because when a new thread is
detected, unlike linux-nat.c, windows-nat.c reports
TARGET_WAITKIND_SPURIOUS to infrun. It's the fact that that event
does not cause a user-visible stop that triggers the problem. When
the target is re-resumed, we call set_running with a wildcard ptid,
which marks all thread as running. That set_running is not suppressed
because the (leader) thread being resumed does not have in_infcall
set. Later, when the infcall finally finishes successfully, nothing
marks all threads back to stopped.
We can trigger the same problem on all targets by having a thread
other than the one that is running the infcall report a breakpoint hit
to infrun, and then have that breakpoint not cause a stop. That's
what the included test does.
The fix is to stop GDB from suppressing the set_running calls while
doing an infcall, and then set the threads back to stopped when the
call finishes, iff they were originally stopped before the infcall
started. (Note the MI *running/*stopped event suppression isn't
affected.)
Tested on x86_64 GNU/Linux.
gdb/ChangeLog:
2015-06-29 Pedro Alves <palves@redhat.com>
PR threads/18127
* infcall.c (run_inferior_call): On infcall success, if the thread
was marked stopped before, reset it back to stopped.
* infrun.c (resume): Don't suppress the set_running calls when
doing an infcall.
(normal_stop): Only discard the finish_thread_state cleanup if the
infcall succeeded.
gdb/testsuite/ChangeLog:
2015-06-29 Pedro Alves <palves@redhat.com>
PR threads/18127
* gdb.threads/hand-call-new-thread.c: New file.
* gdb.threads/hand-call-new-thread.c: New file.
This patch lets GDBServer handle software breakpoints instead of relying
on GDB.
gdb/gdbserver/ChangeLog:
* linux-aarch64-low.c (aarch64_supports_z_point_type): Enable for
Z_PACKET_SW_BP.
GDB uses a "brk #0" instruction to perform a software breakpoint while
GDBServer uses an illegal instruction. Both instructions should match.
When enabling support for the 'Z0' packet, we let GDBServer insert the
breakpoint instruction instead of GDB. And in case of permanent
breakpoints for example, GDB will check if a breakpoint is inserted in the
inferior with `program_breakpoint_here_p (gdbarch, address)', and
compare the instruction read from the inferior with the breakpoint
instruction.
On AArch64, instructions are always little endian so we need to
represent it as an array of bytes, as done in aarch64-tdep.c.
gdb/gdbserver/ChangeLog:
* linux-aarch64-low.c: Remove comment about endianness.
(aarch64_breakpoint): Change type to gdb_byte[]. Set to "brk #0".
(aarch64_breakpoint_at): Change type of insn to gdb_byte[]. Use
memcmp.
* Makefile.in (SIM_EXTRA_CFLAGS): Add -lm.
* armdefs.h (ARMdval, ARMfval): New types.
(ARM_VFP_reg): New union.
(struct ARMul_State): Add VFP_Reg and FPSCR fields.
(VFP_fval, VFP_uword, VFP_sword, VFP_dval, VFP_dword): Accessor
macros for the new VFP_Reg field.
* armemu.c (handle_v6_insn): Add code to handle MOVW, MOVT,
QADD16, QASX, QSAX, QSUB16, QADD8, QSUB8, UADD16, USUB16, UADD8,
USUB8, SEL, REV, REV16, RBIT, BFC, BFI, SBFX and UBFX
instructions.
(handle_VFP_move): New function.
(ARMul_Emulate16): Add checks for newly supported v6
instructions. Add support for VMRS, VMOV and MRC instructions.
(Multiply64): Allow nRdHi == nRm and/or nRdLo == nRm when
operating in v6 mode.
* armemu.h (t_resolved): Define.
* armsupp.c: Include math.h.
(handle_VFP_xfer): New function. Handles VMOV, VSTM, VSTR, VPUSH,
VSTM, VLDM and VPOP instructions.
(ARMul_LDC): Test for co-processor 10 or 11 and pass call to the
new handle_VFP_xfer function.
(ARMul_STC): Likewise.
(handle_VFP_op): New function. Handles VMLA, VMLS, VNMLA, VNMLS,
VNMUL, VMUL, VADD, VSUB, VDIV, VMOV, VABS, VNEG, VSQRT, VCMP,
VCMPE and VCVT instructions.
(ARMul_CDP): Test for co-processor 10 or 11 and pass call to the
new handle_VFP_op function.
* thumbemu.c (tBIT, tBITS, ntBIT, ntBITS): New macros.
(test_cond): New function. Tests a condition and returns non-zero
if the condition has been met.
(handle_IT_block): New function.
(in_IT_block): New function.
(IT_block_allow): New function.
(ThumbExpandImm): New function.
(handle_T2_insn): New function. Handles T2 thumb instructions.
(handle_v6_thumb_insn): Add next_instr and pc parameters.
(ARMul_ThumbDecode): Add support for IT blocks. Add support for
v6 instructions.
* wrapper.c (sim_create_inferior): Detect a thumb address and call
SETT appropriately.
Last year a patch was submitted/approved/commited to eliminate
symbol_matches_domain which was causing this problem. It was later reverted
because it introduced a (severe) performance regression.
Recap:
(gdb) list
1 enum e {A,B,C} e;
2 int main (void) { return 0; }
3
(gdb) p e
Attempt to use a type name as an expression
The parser attempts to find a symbol named "e" of VAR_DOMAIN.
This gets passed down through lookup_symbol and (eventually) into
block_lookup_symbol_primary, which iterates over the block's dictionary
of symbols:
for (sym = dict_iter_name_first (block->dict, name, &dict_iter);
sym != NULL;
sym = dict_iter_name_next (name, &dict_iter))
{
if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
SYMBOL_DOMAIN (sym), domain))
return sym;
}
The problem here is that we have a symbol named "e" in both STRUCT_DOMAIN
and VAR_DOMAIN, and for languages like C++, Java, and Ada, where a tag name
may be used as an implicit typedef of the type, symbol_matches_domain ignores
the difference between VAR_DOMAIN and STRUCT_DOMAIN. As it happens, the
STRUCT_DOMAIN symbol is found first, considered a match, and that symbol is
returned to the parser, eliciting the (now dreaded) error message.
Since this bug exists specifically because we have both STRUCT and VAR_DOMAIN
symbols in a given block/CU, this patch rather simply/naively changes
block_lookup_symbol_primary so that it continues to search for an exact
domain match on the symbol if symbol_matches_domain returns a symbol
which does not exactly match the requested domain.
This "fixes" the immediate problem, but admittedly might uncover other,
related bugs. [Paranoia?] However, it causes no regressions (functional
or performance) in the test suite. A similar change has been made
to block_lookup_symbol for other cases in which this bug might appear.
The tests from the previous submission have been resurrected and updated.
However since we can still be given a matching symbol with a different domain
than requested, we cannot say that a symbol "was not found." The error
messages today will still be the (dreaded) "Attempt to use a type name..."
ChangeLog
PR 16253
* block.c (block_lookup_symbol): For non-function blocks,
continue to search for a symbol with an exact domain match
Otherwise, return any previously found "best domain" symbol.
(block_lookup_symbol_primary): Likewise.
testsuite/ChangeLog
PR 16253
* gdb.cp/var-tag-2.cc: New file.
* gdb.cp/var-tag-3.cc: New file.
* gdb.cp/var-tag-4.cc: New file.
* gdb.cp/var-tag.cc: New file.
* gdb.cp/var-tag.exp: New file.
This patch implements the new option "history remove-duplicates", which
controls the removal of duplicate history entries ("off" by default).
The motivation for this option is to be able to reduce the prevalence of
basic commands such as "up" and "down" in the history file. These
common commands crowd out more unique commands in the history file (when
the history file has a fixed size), and they make navigation of the
history file via ^P, ^N and ^R more inconvenient.
The option takes an integer denoting the number of history entries to
look back at for a history entry that is a duplicate of the latest one.
"history remove-duplicates 1" is equivalent to bash's ignoredups option,
and "history remove-duplicates unlimited" is equivalent to bash's
erasedups option.
[ I decided to go with this integer approach instead of a tri-state enum
because it's slightly more flexible and seemingly more intuitive than
leave/erase/ignore. ]
gdb/ChangeLog:
* NEWS: Mention the new option "history remove-duplicates".
* top.c (history_remove_duplicates): New static variable.
(show_history_remove_duplicates): New static function.
(gdb_add_history): Conditionally remove duplicate history
entries.
(init_main): Add "history remove-duplicates" option.
gdb/doc/ChangeLog:
* gdb.texinfo (Command History): Document the new option
"history remove-duplicates".
gdb/testsuite/ChangeLog:
* gdb.base/history-duplicates.exp: New test.
The implementation is pretty straightforward, with the only caveat being
that the "src", "cmd", "next" and "prev" entries get delibrately added
to the completion list even when the TUI has not yet been initialized
(i.e. has never been enabled during the session), since invoking the
"focus" command with these arguments already works when the TUI has not
yet been initialized.
gdb/ChangeLog:
* tui/tui-win.c (focus_completer): New static function.
(_initialize_tui_win): Set the completion function of the
"focus" command to focus_completer.
gdb/testsuite/ChangeLog:
* gdb.base/completion.exp: Test the completion of the "focus"
command.
GDB tries to skip prologue for .S files according to .debug_line but it then
places the breakpoint to a location where it is never hit.
This is because #defines in .S files cause prologue skipping which is
completely inappropriate, for s390x:
glibc/sysdeps/unix/syscall-template.S
78:/* This is a "normal" system call stub: if there is an error,
79: it returns -1 and sets errno. */
80:
81:T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
82: ret
00000000000f4210 T __select
Line Number Statements:
Extended opcode 2: set Address to 0xf41c8
Advance Line by 80 to 81
Copy
Advance PC by 102 to 0xf422e
Special opcode 6: advance Address by 0 to 0xf422e and Line by 1 to 82
Special opcode 34: advance Address by 2 to 0xf4230 and Line by 1 to 83
Advance PC by 38 to 0xf4256
Extended opcode 1: End of Sequence
Compilation Unit @ offset 0x28b3e0:
<0><28b3eb>: Abbrev Number: 1 (DW_TAG_compile_unit)
<28b3ec> DW_AT_stmt_list : 0x7b439
<28b3f0> DW_AT_low_pc : 0xf41c8
<28b3f8> DW_AT_high_pc : 0xf4256
<28b400> DW_AT_name : ../sysdeps/unix/syscall-template.S
<28b423> DW_AT_comp_dir : /usr/src/debug////////glibc-2.17-c758a686/misc
<28b452> DW_AT_producer : GNU AS 2.23.52.0.1
<28b465> DW_AT_language : 32769 (MIPS assembler)
without debuginfo or with debuginfo and the fix - correct address:
(gdb) b select
Breakpoint 1 at 0xf4210
It is also where .dynsym+.symtab point to:
00000000000f4210 T __select
00000000000f4210 W select
with debuginfo, without the fix:
(gdb) b select
Breakpoint 1 at 0xf41c8: file ../sysdeps/unix/syscall-template.S, line 81.
One part is to behave for asm files similar way like for 'locations_valid':
/* Symtab has been compiled with both optimizations and debug info so that
GDB may stop skipping prologues as variables locations are valid already
at function entry points. */
unsigned int locations_valid : 1;
The other part is to extend the 'locations_valid'-like functionality more.
Both minsym_found and find_function_start_sal need to be patched, otherwise
their addresses do not match and GDB regresses on ppc64:
gdb/ChangeLog
2015-06-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* linespec.c (minsym_found): Reset sal.PC for COMPUNIT_LOCATIONS_VALID
and language_asm..
* symtab.c (find_function_start_sal): Likewise.
gdb/testsuite/ChangeLog
2015-06-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.arch/amd64-prologue-skip.S: New file.
* gdb.arch/amd64-prologue-skip.exp: New file.
_bfd_elf_assign_file_positions_for_non_load will set the sh_size
field for .shstrtab section. There is need to initialize it in
_bfd_elf_compute_section_file_positions.
* elf.c (_bfd_elf_compute_section_file_positions): Don't
initialize sh_size for .shstrtab here.
