https://sourceware.org/ml/gdb-patches/2013-10/msg00477.html
gdb/ChangeLog
* breakpoint.c (update_watchpoint): If hardware watchpoints are
forced off, downgrade them to software watchpoints if possible,
and error out if not possible.
(watch_command_1): Move watchpoint type selection closer to
watchpoint creation, and extend the comments.
gdb/testsuite/ChangeLog
* gdb.base/watchpoints.exp: Add test for setting software
watchpoints of different types before starting the inferior.
I noticed something odd while doing "stepi" over a fork syscall:
...
(gdb) set disassemble-next-line on
...
(gdb) si
0x000000323d4ba7c2 131 pid = ARCH_FORK ();
0x000000323d4ba7a4 <__libc_fork+132>: 64 4c 8b 04 25 10 00 00 00 mov %fs:0x10,%r8
0x000000323d4ba7ad <__libc_fork+141>: 31 d2 xor %edx,%edx
0x000000323d4ba7af <__libc_fork+143>: 4d 8d 90 d0 02 00 00 lea 0x2d0(%r8),%r10
0x000000323d4ba7b6 <__libc_fork+150>: 31 f6 xor %esi,%esi
0x000000323d4ba7b8 <__libc_fork+152>: bf 11 00 20 01 mov $0x1200011,%edi
0x000000323d4ba7bd <__libc_fork+157>: b8 38 00 00 00 mov $0x38,%eax
=> 0x000000323d4ba7c2 <__libc_fork+162>: 0f 05 syscall
0x000000323d4ba7c4 <__libc_fork+164>: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax
0x000000323d4ba7ca <__libc_fork+170>: 0f 87 2b 01 00 00 ja 0x323d4ba8fb <__libc_fork+475>
(gdb) si
0x000000323d4ba7c4 131 pid = ARCH_FORK ();
0x000000323d4ba7a4 <__libc_fork+132>: 64 4c 8b 04 25 10 00 00 00 mov %fs:0x10,%r8
0x000000323d4ba7ad <__libc_fork+141>: 31 d2 xor %edx,%edx
0x000000323d4ba7af <__libc_fork+143>: 4d 8d 90 d0 02 00 00 lea 0x2d0(%r8),%r10
0x000000323d4ba7b6 <__libc_fork+150>: 31 f6 xor %esi,%esi
0x000000323d4ba7b8 <__libc_fork+152>: bf 11 00 20 01 mov $0x1200011,%edi
0x000000323d4ba7bd <__libc_fork+157>: b8 38 00 00 00 mov $0x38,%eax
0x000000323d4ba7c2 <__libc_fork+162>: 0f 05 syscall
=> 0x000000323d4ba7c4 <__libc_fork+164>: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax
0x000000323d4ba7ca <__libc_fork+170>: 0f 87 2b 01 00 00 ja 0x323d4ba8fb <__libc_fork+475>
(gdb) si
0x000000323d4ba7c4 131 pid = ARCH_FORK ();
0x000000323d4ba7a4 <__libc_fork+132>: 64 4c 8b 04 25 10 00 00 00 mov %fs:0x10,%r8
0x000000323d4ba7ad <__libc_fork+141>: 31 d2 xor %edx,%edx
0x000000323d4ba7af <__libc_fork+143>: 4d 8d 90 d0 02 00 00 lea 0x2d0(%r8),%r10
0x000000323d4ba7b6 <__libc_fork+150>: 31 f6 xor %esi,%esi
0x000000323d4ba7b8 <__libc_fork+152>: bf 11 00 20 01 mov $0x1200011,%edi
0x000000323d4ba7bd <__libc_fork+157>: b8 38 00 00 00 mov $0x38,%eax
0x000000323d4ba7c2 <__libc_fork+162>: 0f 05 syscall
=> 0x000000323d4ba7c4 <__libc_fork+164>: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax
0x000000323d4ba7ca <__libc_fork+170>: 0f 87 2b 01 00 00 ja 0x323d4ba8fb <__libc_fork+475>
(gdb) si
0x000000323d4ba7ca 131 pid = ARCH_FORK ();
0x000000323d4ba7a4 <__libc_fork+132>: 64 4c 8b 04 25 10 00 00 00 mov %fs:0x10,%r8
0x000000323d4ba7ad <__libc_fork+141>: 31 d2 xor %edx,%edx
0x000000323d4ba7af <__libc_fork+143>: 4d 8d 90 d0 02 00 00 lea 0x2d0(%r8),%r10
0x000000323d4ba7b6 <__libc_fork+150>: 31 f6 xor %esi,%esi
0x000000323d4ba7b8 <__libc_fork+152>: bf 11 00 20 01 mov $0x1200011,%edi
0x000000323d4ba7bd <__libc_fork+157>: b8 38 00 00 00 mov $0x38,%eax
0x000000323d4ba7c2 <__libc_fork+162>: 0f 05 syscall
0x000000323d4ba7c4 <__libc_fork+164>: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax
=> 0x000000323d4ba7ca <__libc_fork+170>: 0f 87 2b 01 00 00 ja 0x323d4ba8fb <__libc_fork+475>
Notice how the third "si" didn't actually make progress.
Turning on infrun and lin-lwp debug, we see:
(gdb)
infrun: clear_proceed_status_thread (process 5252)
infrun: proceed (addr=0xffffffffffffffff, signal=144, step=1)
infrun: resume (step=1, signal=0), trap_expected=0, current thread [process 5252] at 0x323d4ba7c4
LLR: Preparing to step process 5252, 0, inferior_ptid process 5252
RC: Not resuming sibling process 5252 (not stopped)
LLR: PTRACE_SINGLESTEP process 5252, 0 (resume event thread)
sigchld
infrun: wait_for_inferior ()
linux_nat_wait: [process -1], []
LLW: enter
LNW: waitpid(-1, ...) returned 5252, No child processes
LLW: waitpid 5252 received Child exited (stopped)
LLW: Candidate event Child exited (stopped) in process 5252.
SEL: Select single-step process 5252
LLW: exit
infrun: target_wait (-1, status) =
infrun: 5252 [process 5252],
infrun: status->kind = stopped, signal = SIGCHLD
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x323d4ba7c4
infrun: random signal 20
infrun: stepi/nexti
infrun: stop_stepping
So the inferior got a SIGCHLD (because the fork child exited while
we're doing 'si'), and since that signal is set to "nostop noprint
pass" (by default), it's considered a random signal, so it should not
cause a stop. But, it resulted in an immediate a stop_stepping call
anyway. So the single-step never really finished.
This is a regression caused by:
[[PATCH] Do not respawn signals, take 2.]
https://sourceware.org/ml/gdb-patches/2012-06/msg00702.html
Specifically, caused by this change (as mentioned in the "the lost
step issue first" part of that mail):
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 53db335..3e8dbc8 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -4363,10 +4363,8 @@ process_event_stop_test:
(leaving the inferior at the step-resume-breakpoint without
actually executing it). Either way continue until the
breakpoint is really hit. */
- keep_going (ecs);
- return;
}
-
+ else
/* Handle cases caused by hitting a breakpoint. */
{
That made GDB fall through to the
> /* In all-stop mode, if we're currently stepping but have stopped in
> some other thread, we need to switch back to the stepped thread. */
> if (!non_stop)
part. However, if we don't have a stepped thread to get back to,
we'll now also fall through to all the "stepping" tests. For line
stepping, that'll turn out okay, as we'll just end up realizing the
thread is still in the stepping range, and needs to be re-stepped.
However, for stepi/nexti, we'll reach:
if (ecs->event_thread->control.step_range_end == 1)
{
/* It is stepi or nexti. We always want to stop stepping after
one instruction. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
ecs->event_thread->control.stop_step = 1;
print_end_stepping_range_reason ();
stop_stepping (ecs);
return;
}
and stop, even though the thread actually made no progress. The fix
is to restore the keep_going call, but put it after the "switch back
to the stepped thread" code, and before the stepping tests.
Tested on x86_64 Fedora 17, native and gdbserver. New test included.
gdb/
2013-10-18 Pedro Alves <palves@redhat.com>
PR gdb/16062
* infrun.c (handle_inferior_event): Keep going if we got a random
signal we should not stop for, instead of falling through to the
step tests.
gdb/testsuite/
2013-10-18 Pedro Alves <palves@redhat.com>
PR gdb/16062
* gdb.threads/stepi-random-signal.c: New file.
* gdb.threads/stepi-random-signal.exp: New file.
This patch fixes PR gdb/15995.
The bug here is that gdb's printf command does not flush the output
stream. This makes a printf that is not newline-terminated interleave
incorrectly with other forms of output, such as that generated via a
call to an external program using "shell".
I note that the "output" command already does this flushing.
The fix is to call gdb_flush in printf_command.
Built and regtested on x86-64 Fedora 18.
New test case included.
PR gdb/15995:
* printcmd.c (printcmd): Call gdb_flush.
* gdb.base/printcmds.exp (test_printf): Test printf flushing.
I noticed that one field in elfread.c:struct elfinfo is unused.
This patch removes it.
* elfread.c (struct elfinfo) <stabindexsect>: Remove.
(elf_locate_sections): Update.
As a result of previous patch, extern functions in ada-varobj.c can be
made static, and ada-varobj.h can be removed too.
gdb:
2013-10-17 Yao Qi <yao@codesourcery.com>
* Makefile.in (HFILES_NO_SRCDIR): Remove ada-varobj.h.
* ada-varobj.c: Remove the include of ada-varobj.h.
(ada_varobj_get_number_of_children): Declare.
(ada_varobj_get_name_of_child): Make it static.
(ada_varobj_get_path_expr_of_child): Likewise.
(ada_varobj_get_value_of_child): Likewise.
(ada_varobj_get_type_of_child): Likewise.
(ada_varobj_get_value_of_array_variable): Likewise.
* ada-varobj.h: Remove.
The first one, dw2_get_real_path from gdb/dwarf2read.c, was actually
making use of OBSTACK_CALLOC which already calls "sizeof" for its third
argument.
The second, download_tracepoint_1 from gdb/gdbserver/tracepoint.c, was
explicitly calling "sizeof" inside another "sizeof".
This patch fixed both functions.
gdb/ChangeLog
2013-10-16 Sergio Durigan Junior <sergiodj@redhat.com>
PR gdb/16014
* dwarf2read.c (dw2_get_real_path): Remove unnecessary call to
sizeof.
gdb/gdbserver/ChangeLog
2013-10-16 Sergio Durigan Junior <sergiodj@redhat.com>
PR gdb/16014
* tracepoint.c (download_tracepoint_1): Remove unnecessary double
call to sizeof.
both from gdb/target.c, do a "return" calling another function. But both
are marked as void. Despite the fact that the functions being called are
void as well, this is wrong. This patch fixes this by calling the functions
and then returning in the next line.
2013-10-16 Sergio Durigan Junior <sergiodj@redhat.com>
PR gdb/16042
* target.c (target_disable_btrace): Fix invalid return value for
void function.
(target_teardown_btrace): Likewise.
* elfxx-mips.c (mips_elf_obj_tdata): Add abi_msa_bfd.
(mips_elf_merge_obj_attributes): Set abi_msa_bfd to the first object
file that has a Tag_GNU_MIPS_ABI_MSA attribute.
Merge Tag_GNU_MIPS_ABI_MSA attributes.
(Output_data_got::add_constant_pair): New function.
* powerpc.cc (Output_data_got_powerpc): Override all Output_data_got
methods used so as to first call reserve_ent().
gdb/
* nios2-tdep.c (nios2_reg_names): Use "sstatus" rather than "ba"
as the preferred name of r30.
* nios2-linux-tdep.c (reg_offsets): Likewise.
* features/nios2-cpu.xml: Likewise.
* features/nios2-linux.c: Regenerated.
* features/nios2.c: Regenerated.
* regformats/nios2-linux.dat: Regenerated.
opcodes/
* nios2-opc.c (nios2_builtin_reg): Use "sstatus" rather than "ba"
as the primary name of r30.
gas/
* config/tc-nios2.c (nios2_consume_arg): Make the "ba" warning
also test/refer to "sstatus". Reformat the warning message.
gas/testsuite/
* gas/nios2/warn_nobreak.l: Update text of warning messages.
* gas/nios2/registers.s: Use "sstatus" rather than "ba"
as the primary name of r30.
* gas/nios2/registers.d: Likewise.
gdb/
2013-10-13 Jan Kratochvil <jan.kratochvil@redhat.com>
Canonicalize directories for EXEC_FILENAME.
* exec.c (exec_file_attach): Use gdb_realpath_keepfile for
exec_filename.
* utils.c (gdb_realpath_keepfile): New function.
* utils.h (gdb_realpath_keepfile): New declaration.
gdb/testsuite/
2013-10-13 Jan Kratochvil <jan.kratochvil@redhat.com>
Canonicalize directories for EXEC_FILENAME.
* gdb.base/argv0-symlink.exp
(kept file symbolic link name for info inferiors): New.
(kept directory symbolic link name): Setup kfail.
(kept directory symbolic link name for info inferiors): New.
* elfxx-mips.c (mips_use_local_got_p): New function.
(mips_elf_count_got_symbols, mips_elf_calculate_relocation): Use it.
(_bfd_mips_elf_check_relocs): Set pointer_equality_needed for
GOT and absolute references.
ld/testsuite/
* ld-mips-elf/pic-and-nonpic-6-n32.ad,
ld-mips-elf/pic-and-nonpic-6-n32.dd,
ld-mips-elf/pic-and-nonpic-6-n32.gd,
ld-mips-elf/pic-and-nonpic-6-n32.nd,
ld-mips-elf/pic-and-nonpic-6-n32.rd,
ld-mips-elf/pic-and-nonpic-6-n64.ad,
ld-mips-elf/pic-and-nonpic-6-n64.dd,
ld-mips-elf/pic-and-nonpic-6-n64.gd,
ld-mips-elf/pic-and-nonpic-6-n64.nd,
ld-mips-elf/pic-and-nonpic-6-n64.rd,
ld-mips-elf/pic-and-nonpic-6-o32.ad,
ld-mips-elf/pic-and-nonpic-6-o32.dd,
ld-mips-elf/pic-and-nonpic-6-o32.gd,
ld-mips-elf/pic-and-nonpic-6-o32.nd,
ld-mips-elf/pic-and-nonpic-6-o32.rd: Fix symbol value of extf4.
No longer expect extf3, extf4 and extd2 to be in the global GOT.
