Recognize NT_X86_XSTATE notes in FreeBSD process cores. Recent
FreeBSD versions include a note containing the XSAVE state for each
thread in the process when XSAVE is in use. The note stores a copy of
the current XSAVE mask in a reserved section of the machine-defined
XSAVE state at the same offset as Linux's NT_X86_XSTATE note.
For native processes, use the PT_GETXSTATE_INFO ptrace request to
determine if XSAVE is enabled, and if so the active XSAVE state mask
(that is, the value of %xcr0 for the target process) as well as the
size of XSAVE state area. Use the PT_GETXSTATE and PT_SETXSTATE requests
to fetch and store the XSAVE state, respectively, in the BSD x86
native targets.
In addition, the FreeBSD amd64 and i386 native targets now include
"read_description" target methods to determine the correct x86 target
description for the current XSAVE mask. On FreeBSD amd64 this also
properly returns an i386 target description for 32-bit binaries which
allows the 64-bit GDB to run 32-bit binaries.
Note that the ptrace changes are in the BSD native targets, not the
FreeBSD-specific native targets since that is where the other ptrace
register accesses occur. Of the other BSDs, NetBSD and DragonFly use
XSAVE in the kernel but do not currently export the extended state via
ptrace(2). OpenBSD does not currently support XSAVE.
bfd/ChangeLog:
* elf.c (elfcore_grok_note): Recognize NT_X86_XSTATE on
FreeBSD.
(elfcore_write_xstatereg): Use correct note name on FreeBSD.
gdb/ChangeLog:
* amd64-tdep.c (amd64_target_description): New function.
* amd64-tdep.h: Export amd64_target_description and tdesc_amd64.
* amd64bsd-nat.c [PT_GETXSTATE_INFO]: New variable amd64bsd_xsave_len.
(amd64bsd_fetch_inferior_registers) [PT_GETXSTATE_INFO]: Handle
x86 extended save area.
(amd64bsd_store_inferior_registers) [PT_GETXSTATE_INFO]: Likewise.
* amd64bsd-nat.h: Export amd64bsd_xsave_len.
* amd64fbsd-nat.c (amd64fbsd_read_description): New function.
(_initialize_amd64fbsd_nat): Set "to_read_description" to
"amd64fbsd_read_description".
* amd64fbsd-tdep.c (amd64fbsd_core_read_description): New function.
(amd64fbsd_supply_xstateregset): New function.
(amd64fbsd_collect_xstateregset): New function.
Add "amd64fbsd_xstateregset".
(amd64fbsd_iterate_over_regset_sections): New function.
(amd64fbsd_init_abi): Set "xsave_xcr0_offset" to
"I386_FBSD_XSAVE_XCR0_OFFSET".
Add "iterate_over_regset_sections" gdbarch method.
Add "core_read_description" gdbarch method.
* i386-tdep.c (i386_target_description): New function.
* i386-tdep.h: Export i386_target_description and tdesc_i386.
* i386bsd-nat.c [PT_GETXSTATE_INFO]: New variable i386bsd_xsave_len.
(i386bsd_fetch_inferior_registers) [PT_GETXSTATE_INFO]: Handle
x86 extended save area.
(i386bsd_store_inferior_registers) [PT_GETXSTATE_INFO]: Likewise.
* i386bsd-nat.h: Export i386bsd_xsave_len.
* i386fbsd-nat.c (i386fbsd_read_description): New function.
(_initialize_i386fbsd_nat): Set "to_read_description" to
"i386fbsd_read_description".
* i386fbsd-tdep.c (i386fbsd_core_read_xcr0): New function.
(i386fbsd_core_read_description): New function.
(i386fbsd_supply_xstateregset): New function.
(i386fbsd_collect_xstateregset): New function.
Add "i386fbsd_xstateregset".
(i386fbsd_iterate_over_regset_sections): New function.
(i386fbsd4_init_abi): Set "xsave_xcr0_offset" to
"I386_FBSD_XSAVE_XCR0_OFFSET".
Add "iterate_over_regset_sections" gdbarch method.
Add "core_read_description" gdbarch method.
* i386fbsd-tdep.h: New file.
This testcase does not work as expected in QEMU (aarch64 QEMU in my case). It
fails when trying to manually write the breakpoint instruction to a certain
PC address.
(gdb) p /x addr_bp[0] = buffer[0]^M
Cannot access memory at address 0x400834^M
(gdb) PASS: gdb.base/bp-permanent.exp: always_inserted=off, sw_watchpoint=0: setup: p /x addr_bp[0] = buffer[0]
p /x addr_bp[1] = buffer[1]^M
Cannot access memory at address 0x400835^M
(gdb) PASS: gdb.base/bp-permanent.exp: always_inserted=off, sw_watchpoint=0: setup: p /x addr_bp[1] = buffer[1]
p /x addr_bp[2] = buffer[2]^M
Cannot access memory at address 0x400836^M
(gdb) PASS: gdb.base/bp-permanent.exp: always_inserted=off, sw_watchpoint=0: setup: p /x addr_bp[2] = buffer[2]
p /x addr_bp[3] = buffer[3]^M
Cannot access memory at address 0x400837^M
(gdb) PASS: gdb.base/bp-permanent.exp: always_inserted=off, sw_watchpoint=0: setup: p /x addr_bp[3] = buffer[3]
The following patch prevents a number of failures by detecting this and bailing out in case the target has such a restriction. Writing to .text from within the program isn't any better. It just leads to a SIGSEGV.
Before the patch:
=== gdb Summary ===
After the patch:
=== gdb Summary ===
gdb/testsuite/ChangeLog:
2015-04-13 Luis Machado <lgustavo@codesourcery.com>
* gdb.base/bp-permanent.exp (test): Handle the case of being unable
to write to the .text section.
This testcase seems to assume the target is running Linux, so bare metal,
simulators and other debugging stubs running different OS' will have a
hard time executing some of the commands the testcase issues.
Even restricting the testcase to Linux systems (which the patch below does),
there are still problems with, say, QEMU not providing PID information when
"info inferior" is issued. As a consequence, the subsequent tests will either
fail or will not make much sense.
The attached patch checks if PID information is available. If not, it just
bails out and avoids running into a number of failures.
gdb/testsuite/ChangeLog:
2015-04-13 Luis Machado <lgustavo@codesourcery.com>
* gdb.base/coredump-filter.exp: Restrict test to Linux systems only.
Handle the case of targets that do not provide PID information.
I see the error when I run gdb-sigterm.exp with native-gdbserver
on x86_64-linux.
infrun: prepare_to_wait^M
Cannot execute this command while the target is running.^M
Use the "interrupt" command to stop the target^M
and then try again.^M
gdb.base/gdb-sigterm.exp: expect eof #0: got eof
gdb.base/gdb-sigterm.exp: expect eof #0: stepped 12 times
ERROR OCCURED: : spawn id exp8 not open
while executing
"expect {
-i exp8 -timeout 10
-re "$gdb_prompt $" {
exp_continue
}
-i "$server_spawn_id" eof {
wait -i $expect_out(spawn_id)
unse..."
("uplevel" body line 1)
invoked from within
In gdb-sigterm.exp, SIGTERM is sent to GDB and it exits. However,
Dejagnu or tcl doesn't know this.
This patch is to catch the exception, but error messages are still
shown in the console and gdb.log. In order to avoid this, we also
replace gdb_expect with expect.
gdb/testsuite:
2015-04-13 Yao Qi <yao.qi@linaro.org>
* lib/gdbserver-support.exp (gdb_exit): Catch exception
and use expect instead of gdb_expect.
This commit renames the global array variable "addr" to an unique name
"coredump_var_addr" in the test gdb.base/coredump-filter.exp. This is
needed because global arrays can have name conflicts between tests.
For example, this specific test was conflicting with dmsym.exp,
causing errors like:
ERROR: tcl error sourcing ../../../../../binutils-gdb/gdb/testsuite/gdb.base/dmsym.exp.
ERROR: can't set "addr": variable is array
while executing
"set addr "0x\[0-9a-zA-Z\]+""
(file "../../../../../binutils-gdb/gdb/testsuite/gdb.base/dmsym.exp" line 45)
invoked from within
"source ../../../../../binutils-gdb/gdb/testsuite/gdb.base/dmsym.exp"
("uplevel" body line 1)
invoked from within
"uplevel #0 source ../../../../../binutils-gdb/gdb/testsuite/gdb.base/dmsym.exp"
invoked from within
"catch "uplevel #0 source $test_file_name""
This problem was reported by Yao Qi at:
<https://sourceware.org/ml/gdb-patches/2015-04/msg00373.html>
Message-Id: <1428666671-12926-1-git-send-email-qiyaoltc@gmail.com>
gdb/testsuite/ChangeLog:
2015-04-13 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/coredump-filter.exp: Rename variable "addr" to
"coredump_var_addr" to avoid naming conflict with other testcases.
Pedro Alves:
The commands that enables aren't even documented in the manual.
Judging from that, I assume that only wdb users would ever really
be using the --xdb switch.
I think it's time to drop "support" for the --xdb switch too. I
looked through the commands that that exposes, the only that looked
potentially interesting was "go", but then it's just an alias
for "tbreak+jump", which can easily be done with "define go...end".
I'd rather free up the "go" name for something potentially
more interesting (either run control, or maybe even unrelated,
e.g., for golang).
gdb/ChangeLog
2015-04-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* NEWS (Changes since GDB 7.9): Add removed -xdb.
* breakpoint.c (command_line_is_silent): Remove xdb_commands
conditional.
(_initialize_breakpoint): Remove xdb_commands for bc, ab, sb, db, ba
and lb.
* cli/cli-cmds.c (_initialize_cli_cmds): Remove xdb_commands for v and
va.
* cli/cli-decode.c (find_command_name_length): Remove xdb_commands
conditional.
* defs.h (xdb_commands): Remove declaration.
* f-valprint.c (_initialize_f_valprint): Remove xdb_commands for lc.
* guile/scm-cmd.c (command_classes): Remove xdb from comment.
* infcmd.c (run_no_args_command, go_command): Remove.
(_initialize_infcmd): Remove xdb_commands for S, go, g, R and lr.
* infrun.c (xdb_handle_command): Remove.
(_initialize_infrun): Remove xdb_commands for lz and z.
* main.c (xdb_commands): Remove variable.
(captured_main): Remove "xdb" from long_options.
(print_gdb_help): Remove --xdb from help.
* python/py-cmd.c (gdbpy_initialize_commands): Remove xdb from comment.
* source.c (_initialize_source): Remove xdb_commands for D, ld, / and ?.
* stack.c (backtrace_full_command, args_plus_locals_info)
(current_frame_command): Remove.
(_initialize_stack): Remove xdb_commands for t, T and l.
* symtab.c (_initialize_symtab): Remove xdb_commands for lf and lg.
* thread.c (_initialize_thread): Remove xdb_commands condition.
* tui/tui-layout.c (tui_toggle_layout_command)
(tui_toggle_split_layout_command, tui_handle_xdb_layout): Remove.
(_initialize_tui_layout): Remove xdb_commands for td and ts.
* tui/tui-regs.c (tui_scroll_regs_forward_command)
(tui_scroll_regs_backward_command): Remove.
(_initialize_tui_regs): Remove xdb_commands for fr, gr, sr, +r and -r.
* tui/tui-win.c (tui_xdb_set_win_height_command): Remove.
(_initialize_tui_win): Remove xdb_commands for U and w.
* utils.c (pagination_on_command, pagination_off_command): Remove.
(initialize_utils): Remove xdb_commands for am and sm.
gdb/doc/ChangeLog
2015-04-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.texinfo (Mode Options): Remove -xdb.
gdb/testsuite/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* gdb.threads/signal-while-stepping-over-bp-other-thread.exp: Use
gdb_test_sequence and gdb_assert.
Diffing test results, I noticed:
-PASS: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: with thread-specific bp: next: b *0x0000000000400811 thread 1
+PASS: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: with thread-specific bp: next: b *0x00000000004007d1 thread 1
gdb/testsuite/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* gdb.threads/step-over-trips-on-watchpoint.exp (do_test): Use
test messages that don't include the breakpoint address.
Hi,
ARM linux kernel has some requirements on the address/length setting
for HW breakpoints/watchpoints, but watchpoint-reuse-slot.exp doesn't
consider them and sets HW points on various addresses. Many fails
are causes as a result:
stepi^M
Warning:^M
Could not insert hardware watchpoint 20.^M
Could not insert hardware breakpoints:^M
You may have requested too many hardware breakpoints/watchpoints.^M
^M
(gdb) FAIL: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x watch: : width 2, iter 2: base + 1: stepi advanced
watch *(buf.byte + 2 + 1)@2^M
Hardware watchpoint 388: *(buf.byte + 2 + 1)@2^M
Warning:^M
Could not insert hardware watchpoint 388.^M
Could not insert hardware breakpoints:^M
You may have requested too many hardware breakpoints/watchpoints.^M
^M
(gdb) FAIL: gdb.base/watchpoint-reuse-slot.exp: always-inserted on: watch x watch: : width 2, iter 2: base + 1: watch *(buf.byte + 2 + 1)@2
This patch is to reflect kernel requirements in watchpoint-reuse-slot.exp
in order to skip some tests.
gdb/testsuite:
2015-04-10 Yao Qi <yao.qi@linaro.org>
* gdb.base/watchpoint-reuse-slot.exp (valid_addr_p): Return
false for some offset and width combinations which aren't
supported by linux kernel.
PPC64 currently fails this test like:
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: no thread-specific bp: step: step
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: no thread-specific bp: next: next
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: no thread-specific bp: continue: continue (the program exited)
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: with thread-specific bp: step: step
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: with thread-specific bp: next: next
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: displaced=on: with thread-specific bp: continue: continue (the program exited)
The problem is that PPC is a non-continuable watchpoints architecture
and the displaced stepping code isn't coping with that correctly. On
such targets/architectures, a watchpoint traps _before_ the
instruction executes/completes. On a watchpoint trap, the PC points
at the instruction that triggers the watchpoint (side effects haven't
happened yet). In order to move past the watchpoint, GDB needs to
remove the watchpoint, single-step, and reinsert the watchpoint, just
like when stepping past a breakpoint.
The trouble is that if GDB is stepping over a breakpoint with
displaced stepping, and the instruction under the breakpoint triggers
a watchpoint, we get the watchpoint SIGTRAP, expecting a finished
(hard or software) step trap. Even though the thread's PC hasn't
advanced yet (must remove watchpoint for that), since we get a
SIGTRAP, displaced_step_fixup thinks the single-step finished
successfuly anyway, and calls gdbarch_displaced_step_fixup, which then
adjusts the thread's registers incorrectly.
The fix is to cancel the displaced step if we trip on a watchpoint.
handle_inferior_event then processes the watchpoint event, and starts
a new step-over, here:
...
/* At this point, we are stopped at an instruction which has
attempted to write to a piece of memory under control of
a watchpoint. The instruction hasn't actually executed
yet. If we were to evaluate the watchpoint expression
now, we would get the old value, and therefore no change
would seem to have occurred.
...
ecs->event_thread->stepping_over_watchpoint = 1;
keep_going (ecs);
return;
...
but this time, since we have a watchpoint to step over, watchpoints
are removed from the target, so the step-over succeeds.
The keep_going/resume changes are necessary because if we're stepping
over a watchpoint, we need to remove it from the target - displaced
stepping doesn't help, the copy of the instruction in the scratch pad
reads/writes to the same addresses, thus triggers the watchpoint
too... So without those changes we keep triggering the watchpoint
forever, never making progress. With non-stop that means we'll need
to pause all threads momentarily, which we can't today. We could
avoid that by removing the watchpoint _only_ from the thread that is
moving past the watchpoint, but GDB is not prepared for that today
either. For remote targets, that would need new packets, so good to
be able to step over it in-line as fallback anyway.
gdb/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* infrun.c (displaced_step_fixup): Switch to the event ptid
earlier. If the thread stopped for a watchpoint and the
target/arch has non-continuable watchpoints, cancel the displaced
step.
(resume): Don't start a displaced step if in-line step-over info
is valid.
These tests exercise the infrun.c:proceed code that needs to know to
start new step overs (along with switch_back_to_stepped_thread, etc.).
That code is tricky to get right in the multitude of possible
combinations (at least):
(native | remote)
X (all-stop | all-stop-but-target-always-in-non-stop)
X (displaced-stepping | in-line step-over).
The first two above are properties of the target, but the different
step-over-breakpoint methods should work with any target that supports
them. This patch makes sure we always test both methods on all
targets.
Tested on x86-64 Fedora 20.
gdb/testsuite/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* gdb.threads/step-over-lands-on-breakpoint.exp (do_test): New
procedure, factored out from ...
(top level): ... here. Add "set displaced-stepping" testing axis.
* gdb.threads/step-over-trips-on-watchpoint.exp (do_test): New
parameter "displaced". Use it.
(top level): Use foreach and add "set displaced-stepping" testing
axis.
This test is currently failing like this on (at least) PPC64 and s390x:
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: no thread-specific bp: step: step
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: no thread-specific bp: next: next
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: with thread-specific bp: step: step
FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: with thread-specific bp: next: next
gdb.log:
(gdb) PASS: gdb.threads/step-over-trips-on-watchpoint.exp: no thread-specific bp: step: set scheduler-locking off
step
wait_threads () at ../../../src/gdb/testsuite/gdb.threads/step-over-trips-on-watchpoint.c:49
49 return 1; /* in wait_threads */
(gdb) FAIL: gdb.threads/step-over-trips-on-watchpoint.exp: no thread-specific bp: step: step
The problem is that the test assumes that both the "watch_me = 1;" and
the "other = 1;" lines compile to a single instruction each, which
happens to be true on x86, but no necessarily true everywhere else.
The result is that the test doesn't really test what it wants to test.
Fix it by looking for the instruction that triggers the watchpoint.
gdb/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* gdb.threads/step-over-trips-on-watchpoint.c (child_function):
Remove comment.
* gdb.threads/step-over-trips-on-watchpoint.exp (do_test): Find
both the address of the instruction that triggers the watchpoint
and the address of the instruction immediately after, and use
those addresses for the test. Fix comment.
TL;DR:
When stepping over a breakpoint with displaced stepping, the core must
be notified of all signals, otherwise the displaced step fixup code
confuses a breakpoint trap in the signal handler for the expected trap
indicating the displaced instruction was single-stepped
normally/successfully.
Detailed version:
Running sigstep.exp with displaced stepping on, against my x86
software single-step branch, I got:
FAIL: gdb.base/sigstep.exp: step on breakpoint, to handler: performing step
FAIL: gdb.base/sigstep.exp: next on breakpoint, to handler: performing next
FAIL: gdb.base/sigstep.exp: continue on breakpoint, to handler: performing continue
Turning on debug logs, we see:
(gdb) step
infrun: clear_proceed_status_thread (process 32147)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=1, current thread [process 32147] at 0x400842
displaced: stepping process 32147 now
displaced: saved 0x400622: 49 89 d1 5e 48 89 e2 48 83 e4 f0 50 54 49 c7 c0
displaced: %rip-relative addressing used.
displaced: using temp reg 2, old value 0x3615eafd37, new value 0x40084c
displaced: copy 0x400842->0x400622: c7 81 1c 08 20 00 00 00 00 00
displaced: displaced pc to 0x400622
displaced: run 0x400622: c7 81 1c 08
LLR: Preparing to resume process 32147, 0, inferior_ptid process 32147
LLR: PTRACE_CONT process 32147, 0 (resume event thread)
linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 32147, No child processes
LLW: waitpid 32147 received Alarm clock (stopped)
LLW: PTRACE_CONT process 32147, Alarm clock (preempt 'handle')
LNW: waitpid(-1, ...) returned 0, No child processes
LLW: exit (ignore)
sigchld
infrun: target_wait (-1.0.0, status) =
infrun: -1.0.0 [process -1],
infrun: status->kind = ignore
infrun: TARGET_WAITKIND_IGNORE
infrun: prepare_to_wait
linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 32147, No child processes
LLW: waitpid 32147 received Trace/breakpoint trap (stopped)
CSBB: process 32147 stopped by software breakpoint
LNW: waitpid(-1, ...) returned 0, No child processes
LLW: trap ptid is process 32147.
LLW: exit
infrun: target_wait (-1.0.0, status) =
infrun: 32147.32147.0 [process 32147],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
displaced: restored process 32147 0x400622
displaced: fixup (0x400842, 0x400622), insn = 0xc7 0x81 ...
displaced: restoring reg 2 to 0x3615eafd37
displaced: relocated %rip from 0x400717 to 0x400937
infrun: stop_pc = 0x400937
infrun: delayed software breakpoint trap, ignoring
infrun: no line number info
infrun: stop_waiting
0x0000000000400937 in __dso_handle ()
1: x/i $pc
=> 0x400937: and %ah,0xa0d64(%rip) # 0x4a16a1
(gdb) FAIL: gdb.base/sigstep.exp: displaced=on: step on breakpoint, to handler: performing step
What should have happened is that the breakpoint hit in the signal
handler should have been presented to the user. But note that
"preempt 'handle'" -- what happened instead is that
displaced_step_fixup confused the breakpoint in the signal handler for
the expected SIGTRAP indicating the displaced instruction was
single-stepped normally/successfully.
This should be affecting all software single-step targets in the same
way.
The fix is to make sure the core sees all signals when displaced
stepping, just like we already must see all signals when doing an
stepping over a breakpoint in-line. We now get:
infrun: target_wait (-1.0.0, status) =
infrun: 570.570.0 [process 570],
infrun: status->kind = stopped, signal = GDB_SIGNAL_ALRM
infrun: TARGET_WAITKIND_STOPPED
displaced: restored process 570 0x400622
infrun: stop_pc = 0x400842
infrun: random signal (GDB_SIGNAL_ALRM)
infrun: signal arrived while stepping over breakpoint
infrun: inserting step-resume breakpoint at 0x400842
infrun: resume (step=0, signal=GDB_SIGNAL_ALRM), trap_expected=0, current thread [process 570] at 0x400842
LLR: Preparing to resume process 570, Alarm clock, inferior_ptid process 570
LLR: PTRACE_CONT process 570, Alarm clock (resume event thread)
infrun: prepare_to_wait
linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 0, No child processes
LLW: exit (ignore)
infrun: target_wait (-1.0.0, status) =
infrun: -1.0.0 [process -1],
infrun: status->kind = ignore
sigchld
infrun: TARGET_WAITKIND_IGNORE
infrun: prepare_to_wait
linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 570, No child processes
LLW: waitpid 570 received Trace/breakpoint trap (stopped)
CSBB: process 570 stopped by software breakpoint
LNW: waitpid(-1, ...) returned 0, No child processes
LLW: trap ptid is process 570.
LLW: exit
infrun: target_wait (-1.0.0, status) =
infrun: 570.570.0 [process 570],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x400717
infrun: BPSTAT_WHAT_STOP_NOISY
infrun: stop_waiting
Breakpoint 3, handler (sig=14) at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/sigstep.c:35
35 done = 1;
Hardware single-step targets already behave this way, because the
Linux backends (both native and gdbserver) always report signals to
the core if the thread was single-stepping.
As mentioned in the new comment in do_target_resume, we can't fix this
by instead making the displaced_step_fixup phase skip fixing up the PC
if the single step stopped somewhere we didn't expect. Here's what
the backtrace would look like if we did that:
Breakpoint 3, handler (sig=14) at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/sigstep.c:35
35 done = 1;
1: x/i $pc
=> 0x400717 <handler+7>: movl $0x1,0x200943(%rip) # 0x601064 <done>
(gdb) bt
#0 handler (sig=14) at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/sigstep.c:35
#1 <signal handler called>
#2 0x0000000000400622 in _start ()
(gdb) FAIL: gdb.base/sigstep.exp: displaced=on: step on breakpoint, to handler: backtrace
gdb/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* infrun.c (displaced_step_in_progress): New function.
(do_target_resume): Advise target to report all signals if
displaced stepping.
gdb/testsuite/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
* gdb.base/sigstep.exp (breakpoint_to_handler)
(breakpoint_to_handler_entry): New parameter 'displaced'. Use it.
Test "backtrace" in handler.
(breakpoint_over_handler): New parameter 'displaced'. Use it.
(top level): Add new "displaced" test axis to
breakpoint_to_handler, breakpoint_to_handler_entry and
breakpoint_over_handler.
The problem is that with hardware step targets and displaced stepping,
"signal FOO" when stopped at a breakpoint steps the breakpoint
instruction at the same time it delivers a signal. This results in
tp->stepped_breakpoint set, but no step-resume breakpoint set. When
the next stop event arrives, GDB crashes. Irrespective of whether we
should do something more/different to step past the breakpoint in this
scenario (e.g., PR 18225), it's just wrong to assume there'll be a
step-resume breakpoint set (and was not the original intention).
gdb/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
PR gdb/18216
* infrun.c (process_event_stop_test): Don't assume a step-resume
is set if tp->stepped_breakpoint is true.
gdb/testsuite/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
PR gdb/18216
* gdb.threads/multiple-step-overs.exp: Remove expected eof.
Recent patch series "V2 All-stop on top of non-stop" causes a SIGSEGV
in the test case,
> -PASS: gdb.base/info-shared.exp: continue to breakpoint: library function #4
> +FAIL: gdb.base/info-shared.exp: continue to breakpoint: library function #4
>
> continue^M
> Continuing.^M
> ^M
> Program received signal SIGSEGV, Segmentation fault.^M
> 0x40021564 in ?? () gdb/testsuite/gdb.base/info-shared-solib1.so^M
> (gdb) FAIL: gdb.base/info-shared.exp: continue to breakpoint: library function #4
and an ARM displaced stepping bug is exposed. It can be reproduced by
the modified gdb.arch/arm-disp-step.exp as below,
continue^M
Continuing.^M
^M
Program received signal SIGSEGV, Segmentation fault.^M
0xa713cfcc in ?? ()^M
(gdb) FAIL: gdb.arch/arm-disp-step.exp: continue to breakpoint: continue to test_add_rn_pc_end
This patch is to fix it.
gdb:
2015-04-10 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (install_alu_reg): Update comment.
(thumb_copy_alu_reg): Remove local variable rn. Update
debugging message. Use r2 instead of r1 in the modified
instruction.
gdb/testsuite:
2015-04-10 Yao Qi <yao.qi@linaro.org>
* gdb.arch/arm-disp-step.S (main): Call test_add_rn_pc.
(test_add_rn_pc): New function.
* gdb.arch/arm-disp-step.exp (test_add_rn_pc): New proc.
(top level): Invoke test_add_rn_pc.
Running break-interp.exp with the target always in non-stop mode trips
on PR13858, as enabling non-stop also enables displaced stepping.
The problem is that when GDB doesn't know where the entry point is, it
doesn't know where to put the displaced stepping scratch pad. The
test added by this commit exercises this. Without the fix, we get:
(gdb) PASS: gdb.base/step-over-no-symbols.exp: displaced=on: break *$pc
set displaced-stepping on
(gdb) PASS: gdb.base/step-over-no-symbols.exp: displaced=on: set displaced-stepping on
stepi
0x00000000004005be in ?? ()
Entry point address is not known.
(gdb) PASS: gdb.base/step-over-no-symbols.exp: displaced=on: stepi
p /x $pc
$2 = 0x4005be
(gdb) PASS: gdb.base/step-over-no-symbols.exp: displaced=on: get after PC
FAIL: gdb.base/step-over-no-symbols.exp: displaced=on: advanced
The fix switches all GNU/Linux ports to get the entry point from
AT_ENTRY in the target auxiliary vector instead of from symbols. This
is currently only done by PPC when Cell debugging is enabled, but I
think all archs should be able to do the same. Note that
ppc_linux_displaced_step_location cached the result, I'm guessing to
avoid constantly re-fetching the auxv out of remote targets, but
that's no longer necessary nowadays, as the auxv blob is itself cached
in the inferior object. The ppc_linux_entry_point_addr global is
obviously bad for multi-process too nowadays.
Tested on x86-64 (-m64/-m32), PPC64 (-m64/-m32) and S/390 GNU/Linux.
Yao tested the new test on ARM as well.
gdb/ChangeLog:
2015-04-10 Pedro Alves <palves@redhat.com>
PR gdb/13858
* amd64-linux-tdep.c (amd64_linux_init_abi_common): Install
linux_displaced_step_location as gdbarch_displaced_step_location
hook.
* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
* i386-linux-tdep.c (i386_linux_init_abi): Likewise.
* linux-tdep.c (linux_displaced_step_location): New function,
based on ppc_linux_displaced_step_location.
* linux-tdep.h (linux_displaced_step_location): New declaration.
* ppc-linux-tdep.c (ppc_linux_entry_point_addr): Delete.
(ppc_linux_inferior_created, ppc_linux_displaced_step_location):
Delete.
(ppc_linux_init_abi): Install linux_displaced_step_location as
gdbarch_displaced_step_location hook, even without Cell/B.E..
(_initialize_ppc_linux_tdep): Don't install
ppc_linux_inferior_created as inferior_created observer.
* s390-linux-tdep.c (s390_gdbarch_init): Install
linux_displaced_step_location as gdbarch_displaced_step_location
hook.
gdb/testsuite/
2015-04-10 Pedro Alves <palves@redhat.com>
PR gdb/13858
* gdb.base/step-over-no-symbols.exp: New file.
gdb/doc/ChangeLog
2015-04-10 Jan Kratochvil <jan.kratochvil@redhat.com>
Eli Zaretskii <eliz@gnu.org>
* gdb.texinfo (Compiling and Injecting Code): Describe set debug
compile, show debug compile. New subsection Compilation options for
the compile command. New subsection Compiler search for the compile
command.
This commit introduces a new shared function to replace three
identical functions in various places in the codebase.
gdb/ChangeLog:
* common/common-remote-fileio.h (remote_fileio_to_fio_error):
New declaration.
* common/common-remote-fileio.c (remote_fileio_to_fio_error):
New function, factored out the named functions below.
* inf-child.c (gdb/fileio.h): Remove include.
(common-remote-fileio.h): New include.
(inf_child_errno_to_fileio_error): Remove function. Update
all callers to use remote_fileio_to_fio_error.
* remote-fileio.c (remote_fileio_errno_to_target): Likewise.
gdb/gdbserver/ChangeLog:
* hostio-errno.c (errno_to_fileio_error): Remove function.
Update caller to use remote_fileio_to_fio_error.
gdb/ChangeLog:
2015-04-09 Pedro Alves <palves@redhat.com>
* gnulib/update-gnulib.sh (aclocal version check): Filter out
"called too early to check prototype".
Hi,
I see the following error on arm linux gdbserver,
continue^M
Continuing.^M
../../../binutils-gdb/gdb/gdbserver/linux-arm-low.c:458: A problem internal to GDBserver has been detected.^M
raw_bkpt_type_to_arm_hwbp_type: unhandled raw type^M
Remote connection closed^M
(gdb) FAIL: gdb.base/cond-eval-mode.exp: hbreak: continue
After we make GDBserver handling Zx/zx packet idempotent,
[PATCH 3/3] [GDBserver] Make Zx/zx packet handling idempotent.
https://sourceware.org/ml/gdb-patches/2014-04/msg00480.html
> Now removal/insertion of all kinds of breakpoints/watchpoints, either
> internal, or from GDB, always go through the target methods.
GDBserver handles all kinds of breakpoints/watchpoints through target
methods. However, some target backends, such as arm, don't support Z0
packet but need software breakpoint to do breakpoint stepping over in
linux-low.c:start_step_over,
if (can_hardware_single_step ())
{
step = 1;
}
else
{
CORE_ADDR raddr = (*the_low_target.breakpoint_reinsert_addr) ();
set_reinsert_breakpoint (raddr);
step = 0;
}
a software breakpoint is requested to the backend, and the error is
triggered. This problem should affect targets having
breakpoint_reinsert_addr hooked.
Instead of handling memory breakpoint in these affected linux backend,
this patch handles memory breakpoint in linux_{insert,remove}_point,
that, if memory breakpoint is requested, call
{insert,remove}_memory_breakpoint respectively. Then, it becomes
unnecessary to handle memory breakpoint for linux x86 backend, so
this patch removes the code there.
This patch is tested with GDBserver on x86_64-linux and arm-linux
(-marm, -mthumb). Note that there are still some fails in
gdb.base/cond-eval-mode.exp with -mthumb, because GDBserver doesn't
know how to select the correct breakpoint instruction according to
the arm-or-thumb-mode of requested address. This is a separate
issue, anyway.
gdb/gdbserver:
2015-04-09 Yao Qi <yao.qi@linaro.org>
* linux-low.c (linux_insert_point): Call
insert_memory_breakpoint if TYPE is raw_bkpt_type_sw.
(linux_remove_point): Call remove_memory_breakpoint if type is
raw_bkpt_type_sw.
* linux-x86-low.c (x86_insert_point): Don't call
insert_memory_breakpoint.
(x86_remove_point): Don't call remove_memory_breakpoint.
This patch is related to PR python/16699, and is an improvement over the
patch posted here:
<https://sourceware.org/ml/gdb-patches/2014-03/msg00301.html>
Keith noticed that, when using the "complete" command on GDB to complete
a Python command, some strange things could happen. In order to
understand what can go wrong, I need to explain how the Python
completion mechanism works.
When the user requests a completion of a Python command by using TAB,
GDB will first try to determine the right set of "brkchars" that will be
used when doing the completion. This is done by actually calling the
"complete" method of the Python class. Then, when we already know the
"brkchars" that will be used, we call the "complete" method again, for
the same values.
If you read the thread mentioned above, you will see that one of the
design decisions was to make the "cmdpy_completer_helper" (which is the
function the does the actual calling of the "complete" method) cache the
first result of the completion, since this result will be used in the
second call, to do the actual completion.
The problem is that the "complete" command does not process the
brkchars, and the current Python completion mechanism (improved by the
patch mentioned above) relies on GDB trying to determine the brkchars,
and then doing the completion itself. Therefore, when we use the
"complete" command instead of doing a TAB-completion on GDB, there is a
scenario where we can use the invalid cache of a previous Python command
that was completed before. For example:
(gdb) A <TAB>
(gdb) complete B
B value1
B value10
B value2
B value3
B value4
B value5
B value6
B value7
B value8
B value9
(gdb) B <TAB>
comp1 comp2 comp4 comp6 comp8
comp10 comp3 comp5 comp7 comp9
Here, we see that "complete B " gave a different result than "B <TAB>".
The reason for that is because "A <TAB>" was called before, and its
completion results were "value*", so when GDB tried to "complete B " it
wrongly answered with the results for A. The problem here is using a
wrong cache (A's cache) for completing B.
We tried to come up with a solution that would preserve the caching
mechanism, but it wasn't really possible. So I decided to completely
remove the cache, and doing the method calling twice for every
completion. This is not optimal, but I do not think it will impact
users noticeably.
It is worth mentioning another small issue that I found. The code was
doing:
wordobj = PyUnicode_Decode (word, sizeof (word), host_charset (), NULL);
which is totally wrong, because using "sizeof" here will lead to always
the same result. So I changed this to use "strlen". The testcase also
catches this problem.
Keith kindly expanded the existing testcase to cover the problem
described above, and everything is passing.
gdb/ChangeLog:
2015-04-08 Sergio Durigan Junior <sergiodj@redhat.com>
PR python/16699
* python/py-cmd.c (cmdpy_completer_helper): Adjust function to not
use a caching mechanism. Adjust comments and code to reflect
that. Replace 'sizeof' by 'strlen' when fetching 'wordobj'.
(cmdpy_completer_handle_brkchars): Adjust call to
cmdpy_completer_helper. Call Py_XDECREF for 'resultobj'.
(cmdpy_completer): Likewise.
gdb/testsuite/ChangeLog:
2015-04-08 Keith Seitz <keiths@redhat.com>
PR python/16699
* gdb.python/py-completion.exp: New tests for completion.
* gdb.python/py-completion.py (CompleteLimit1): New class.
(CompleteLimit2): Likewise.
(CompleteLimit3): Likewise.
(CompleteLimit4): Likewise.
(CompleteLimit5): Likewise.
(CompleteLimit6): Likewise.
(CompleteLimit7): Likewise.
Both PRs are triggered by the same use case.
PR18214 is about software single-step targets. On those, the 'resume'
code that detects that we're stepping over a breakpoint and delivering
a signal at the same time:
/* Currently, our software single-step implementation leads to different
results than hardware single-stepping in one situation: when stepping
into delivering a signal which has an associated signal handler,
hardware single-step will stop at the first instruction of the handler,
while software single-step will simply skip execution of the handler.
...
Fortunately, we can at least fix this particular issue. We detect
here the case where we are about to deliver a signal while software
single-stepping with breakpoints removed. In this situation, we
revert the decisions to remove all breakpoints and insert single-
step breakpoints, and instead we install a step-resume breakpoint
at the current address, deliver the signal without stepping, and
once we arrive back at the step-resume breakpoint, actually step
over the breakpoint we originally wanted to step over. */
doesn't handle the case of _another_ thread also needing to step over
a breakpoint. Because the other thread is just resumed at the PC
where it had stopped and a breakpoint is still inserted there, the
thread immediately re-traps the same breakpoint. This test exercises
that. On software single-step targets, it fails like this:
KFAIL: gdb.threads/multiple-step-overs.exp: displaced=off: signal thr3: continue to sigusr1_handler
KFAIL: gdb.threads/multiple-step-overs.exp: displaced=off: signal thr2: continue to sigusr1_handler
gdb.log (simplified):
(gdb) continue
Continuing.
Breakpoint 4, child_function_2 (arg=0x0) at src/gdb/testsuite/gdb.threads/multiple-step-overs.c:66
66 callme (); /* set breakpoint thread 2 here */
(gdb) thread 3
(gdb) queue-signal SIGUSR1
(gdb) thread 1
[Switching to thread 1 (Thread 0x7ffff7fc1740 (LWP 24824))]
#0 main () at src/gdb/testsuite/gdb.threads/multiple-step-overs.c:106
106 wait_threads (); /* set wait-threads breakpoint here */
(gdb) break sigusr1_handler
Breakpoint 5 at 0x400837: file src/gdb/testsuite/gdb.threads/multiple-step-overs.c, line 31.
(gdb) continue
Continuing.
[Switching to Thread 0x7ffff7fc0700 (LWP 24828)]
Breakpoint 4, child_function_2 (arg=0x0) at src/gdb/testsuite/gdb.threads/multiple-step-overs.c:66
66 callme (); /* set breakpoint thread 2 here */
(gdb) KFAIL: gdb.threads/multiple-step-overs.exp: displaced=off: signal thr3: continue to sigusr1_handler
For good measure, I made the test try displaced stepping too. And
then I found it crashes GDB on x86-64 (a hardware step target), but
only when displaced stepping... :
KFAIL: gdb.threads/multiple-step-overs.exp: displaced=on: signal thr1: continue to sigusr1_handler (PRMS: gdb/18216)
KFAIL: gdb.threads/multiple-step-overs.exp: displaced=on: signal thr2: continue to sigusr1_handler (PRMS: gdb/18216)
KFAIL: gdb.threads/multiple-step-overs.exp: displaced=on: signal thr3: continue to sigusr1_handler (PRMS: gdb/18216)
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x000000000062a83a in process_event_stop_test (ecs=0x7fff847eeee0) at src/gdb/infrun.c:4964
4964 if (sr_bp->loc->permanent
Setting up the environment for debugging gdb.
Breakpoint 1 at 0x79fcfc: file src/gdb/common/errors.c, line 54.
Breakpoint 2 at 0x50a26c: file src/gdb/cli/cli-cmds.c, line 217.
(top-gdb) p sr_bp
$1 = (struct breakpoint *) 0x0
(top-gdb) bt
#0 0x000000000062a83a in process_event_stop_test (ecs=0x7fff847eeee0) at src/gdb/infrun.c:4964
#1 0x000000000062a1af in handle_signal_stop (ecs=0x7fff847eeee0) at src/gdb/infrun.c:4715
#2 0x0000000000629097 in handle_inferior_event (ecs=0x7fff847eeee0) at src/gdb/infrun.c:4165
#3 0x0000000000627482 in fetch_inferior_event (client_data=0x0) at src/gdb/infrun.c:3298
#4 0x000000000064ad7b in inferior_event_handler (event_type=INF_REG_EVENT, client_data=0x0) at src/gdb/inf-loop.c:56
#5 0x00000000004c375f in handle_target_event (error=0, client_data=0x0) at src/gdb/linux-nat.c:4658
#6 0x0000000000648c47 in handle_file_event (file_ptr=0x2e0eaa0, ready_mask=1) at src/gdb/event-loop.c:658
The all-stop-non-stop series fixes this, but meanwhile, this augments
the multiple-step-overs.exp test to cover this, KFAILed.
gdb/testsuite/ChangeLog:
2015-04-08 Pedro Alves <palves@redhat.com>
PR gdb/18214
PR gdb/18216
* gdb.threads/multiple-step-overs.c (sigusr1_handler): New
function.
(main): Install it as SIGUSR1 handler.
* gdb.threads/multiple-step-overs.exp (setup): Remove 'prefix'
parameter. Always use "setup" as prefix. Toggle "set
displaced-stepping" off/on depending on global. Don't switch to
thread 1 here.
(top level): Add displaced stepping "off/on" test axis. Update
"setup" calls. Wrap each subtest with with_test_prefix. Test
continuing with a queued signal in each thread.
Nowadays, in infrun.c:resume, the setting to 'step' variable is like:
if (use_displaced_stepping (gdbarch)
&& tp->control.trap_expected
&& sig == GDB_SIGNAL_0
&& !current_inferior ()->waiting_for_vfork_done)
{
}
/* Do we need to do it the hard way, w/temp breakpoints? */
else if (step)
step = maybe_software_singlestep (gdbarch, pc); <-- [1]
...
if (execution_direction != EXEC_REVERSE
&& step && breakpoint_inserted_here_p (aspace, pc))
{
...
if (gdbarch_cannot_step_breakpoint (gdbarch)) <-- [2]
step = 0;
}
spu doesn't have displaced stepping and uses software single step,
so 'step' is set to zero in [1], and [2] becomes unreachable as a
result. So don't have to call set_gdbarch_cannot_step_breakpoint
in spu_gdbarch_init.
gdb:
2015-04-08 Yao Qi <yao.qi@linaro.org>
* spu-tdep.c (spu_gdbarch_init): Don't call
set_gdbarch_cannot_step_breakpoint.
The recent actions.exp change to check gdb_run_cmd succeeded caught
further problems. The test now fails like this
with --target_board=native-extended-gdbserver:
FAIL: gdb.trace/actions.exp: Can't run to main
gdb.log shows:
(gdb) run
Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.trace/actions
Running the default executable on the remote target failed; try "set remote exec-file"?
(gdb) FAIL: gdb.trace/actions.exp: Can't run to main
The problem is that a gdb_load call is missing.
Grepping around for similar problems in other tests, I found that
infotrace.exp and while-stepping.exp should be likewise affected. And
indeed this is what we get today:
FAIL: gdb.trace/infotrace.exp: tstart
FAIL: gdb.trace/infotrace.exp: continue to end (the program is no longer running)
FAIL: gdb.trace/infotrace.exp: tstop
FAIL: gdb.trace/infotrace.exp: 2.6: info tracepoints (trace buffer usage)
FAIL: gdb.trace/while-stepping.exp: tstart
FAIL: gdb.trace/while-stepping.exp: tstop
FAIL: gdb.trace/while-stepping.exp: tfile: info tracepoints
FAIL: gdb.trace/while-stepping.exp: ctf: info tracepoints
while-stepping.exp even has the same race bug actions.exp had.
After this, {actions,infotrace,while-stepping}.exp all pass cleanly
with the native-extended-gdbserver board.
gdb/testsuite/ChangeLog:
2015-04-08 Pedro Alves <palves@redhat.com>
* gdb.trace/actions.exp: Use gdb_load before gdb_run_cmd.
* gdb.trace/infotrace.exp: Use gdb_load before gdb_run_cmd. Use
gdb_breakpoint instead of gdb_test that doesn't expect anything.
Return early if running to main fails.
* gdb.trace/while-stepping.exp: Likewise.
The gdb.base/interrupt.exp test is important for testing system call
restarting, but because it depends on inferior I/O, it ends up skipped
against gdbserver. This patch adjusts the test to use send_inferior
and $inferior_spawn_id so it works against GDBserver.
gdb/testsuite/ChangeLog:
2015-04-07 Pedro Alves <palves@redhat.com>
* gdb.base/interrupt.exp: Don't skip if $inferior_spawn_id !=
$gdb_spawn_id. Use send_inferior and $inferior_spawn_id to
interact with inferior program.
Some important tests, like gdb.base/interrupt.exp end up skipped
against gdbserver, because they depend on inferior I/O, which
gdbserver doesn't do.
This patch adds a mechanism that makes it possible to make them work.
It adds a new "inferior_spawn_id" global that is the spawn ID used for
I/O interaction with the inferior. By default, for native targets, or
remote targets that can do I/O through GDB (semi-hosting) this will be
the same as the gdb/host spawn ID. Otherwise, the board may set this
to some other spawn ID. When debugging with GDBserver, this will be
set to GDBserver's spawn ID.
Then tests can use send_inferior instead of send_gdb to send input to
the inferior, and use expect's "-i" switch to select which spawn ID to
use for matching input/output. That is, something like this will now
work:
send_inferior "echo me\n"
gdb_test_multiple "continue" "test msg" {
-i "$inferior_spawn_id" -re "echo me\r\necho\r\n" {
...
}
}
Or even:
gdb_test_multiple "continue" "test msg" {
-i "$inferior_spawn_id" -re "hello world" {
...
}
-i "$gdb_spawn_id" -re "error.*$gdb_prompt $" {
...
}
}
Of course, by default, gdb_test_multiple still matches with
$gdb_spawn_id.
gdb/testsuite/ChangeLog:
2015-04-07 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (inferior_spawn_id): New global.
(gdb_test_multiple): Handle "-i". Reset the spawn id to GDB's
spawn id after processing the user code.
(default_gdb_start): Set inferior_spawn_id.
(send_inferior): New procedure.
* lib/gdbserver-support.exp (gdbserver_start): Set
inferior_spawn_id.
(close_gdbserver, gdb_exit): Unset inferior_spawn_id.
I adjusted a test to do 'expect -i $server_spawn_id -re ...', and saw
really strange behavior. Whether that expect would work, depended on
whether GDB would also send output and the same expect matched it too
(on $gdb_spawn_id). I was perplexed until I noticed that
gdbserver_spawn spawns gdbserver and then uses expect_background to
reap gdbserver. That expect_background conflicts/races with any
"expect -i $server_spawn_id" done anywhere else in parallel...
In order to make it possible for tests to read inferior I/O out of
$server_spawn_id, we to get rid of that expect_background. This patch
makes us instead reap gdbserver's spawn id when GDB exits. If GDB is
still around, this gives a chance for gdbserver to exit cleanly. The
current code in gdb_finish uses "kill", but that doesn't work with
extended-remote (gdbserver doesn't exit). We now use "monitor exit"
instead which works in both remote and extended-remote modes.
gdb/testsuite/ChangeLog:
2015-04-07 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (gdb_finish): Delete persistent gdbserver handling.
* lib/gdbserver-support.exp (gdbserver_start): Make
$server_spawn_id global.
(gdbserver_start): Don't wait for gdbserver's spawn id with
expect_background.
(close_gdbserver): New procedure.
(gdb_exit): Rename the default version and reimplement.
While teaching gdb_test_multiple to forward "-i" to gdb_expect, I
found that with:
gdb_test_multiple (...) {
-i $some_variable -re "..." {}
}
$some_variable was not getting expanded in the gdb_test_multiple
caller's scope. This is a bug inside gdb_test_multiple. When
processing an argument in passed in user code, it was appending the
original argument literally, instead of appending the uplist'ed
argument.
gdb/testsuite/ChangeLog:
2015-04-07 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (gdb_test_multiple): When processing an argument,
append the substituted item, not the original item.
Working on splitting gdb and inferior output handling in this test, I
noticed a race that happens to be masked out today.
The test sends "a\n" to the inferior, and then inferior echoes back
"a\n".
If expect manages to read only the first "a\r\n" into its buffer, then
this matches:
-re "^a\r\n(|a\r\n)$" {
and leaves the second "a\r\n" in output.
Then the next test that processes inferior I/O sends "data\n", and expects:
-re "^(\r\n|)data\r\n(|data\r\n)$"
which fails given the anchor and given "a\r\n" is still in the buffer.
This is masked today because the test relies on inferior I/O being
done on GDB's terminal, and there are tested GDB commands in between,
which consume the "a\r\n" that was left in the output.
We don't support SunOS4 anymore, so just remove the workaround.
gdb/testsuite/ChangeLog
2015-04-07 Pedro Alves <palves@redhat.com>
* gdb.base/interrupt.exp: Don't handle the case of the inferior
output appearing once only.
I saw this on PPC64 once:
not installed on target
(gdb) PASS: gdb.trace/actions.exp: 5.10a: verify teval actions set for two tracepoints
break main
Breakpoint 4 at 0x10000c6c: file ../../../src/gdb/testsuite/gdb.trace/actions.c, line 139.
(gdb) PASS: gdb.trace/actions.exp: break main
run
Starting program: /home/palves/gdb/build/gdb/testsuite/outputs/gdb.trace/actions/actions
tstatus
Breakpoint 4, main (argc=1, argv=0x3fffffffebb8, envp=0x3fffffffebc8) at ../../../src/gdb/testsuite/gdb.trace/actions.c:139
139 begin ();
(gdb) tstatus
Trace can not be run on this target.
(gdb) actions 1
Enter actions for tracepoint 1, one per line.
End with a line saying just "end".
>collect $regs
>end
(gdb) PASS: gdb.trace/actions.exp: set actions for first tracepoint
tstart
You can't do that when your target is `native'
(gdb) FAIL: gdb.trace/actions.exp: tstart
info tracepoints 1
Num Type Disp Enb Address What
1 tracepoint keep y 0x00000000100007c8 in gdb_c_test at ../../../src/gdb/testsuite/gdb.trace/actions.c:74
collect $regs
not installed on target
...
followed by a cascade of FAILs. The "tstatus" was supposed to detect
that this target (native) can't do tracepoints, but, alas, it didn't.
That detection failed because 'gdb_test "break main"' doesn't expect
anything, and then the output was slow enough that 'gdb_test ""
"Breakpoint .*"' matched the output of "break main"...
The fix is to use gdb_breakpoint instead. Also check the result of
gdb_test while at it.
Tested on x86-64 Fedora 20, native and gdbserver.
gdb/testsuite/ChangeLog:
2015-04-07 Pedro Alves <palves@redhat.com>
* gdb.trace/actions.exp: Use gdb_breakpoint instead of gdb_test
that doesn't expect anything. Return early if running to main
fails.
On GNU/Linux, if the running kernel supports clone events, then
linux-thread-db.c defers thread listing to the target beneath:
static void
thread_db_update_thread_list (struct target_ops *ops)
{
...
if (target_has_execution && !thread_db_use_events ())
ops->beneath->to_update_thread_list (ops->beneath);
else
thread_db_update_thread_list_td_ta_thr_iter (ops);
...
}
However, when live debugging, the target beneath, linux-nat.c, does
not implement the to_update_thread_list method. The result is that if
a thread is marked exited (because it can't be deleted right now,
e.g., it was the selected thread), then it won't ever be deleted,
until the process exits or is killed/detached.
A similar thing happens with the remote.c target. Because its
target_update_thread_list implementation skips exited threads when it
walks the current thread list looking for threads that no longer exits
on the target side, using ALL_NON_EXITED_THREADS_SAFE, stale exited
threads are never deleted.
This is not a big deal -- I can't think of any way this might be user
visible, other than gdb's memory growing a tiny bit whenever a thread
gets stuck in exited state. Still, might as well clean things up
properly.
All other targets use prune_threads, so are unaffected.
The fix adds a ALL_THREADS_SAFE macro, that like
ALL_NON_EXITED_THREADS_SAFE, walks the thread list and allows deleting
the iterated thread, and uses that in places that are walking the
thread list in order to delete threads. Actually, after converting
linux-nat.c and remote.c to use this, we find the only other user of
ALL_NON_EXITED_THREADS_SAFE is also walking the list to delete
threads. So we convert that too, and end up deleting
ALL_NON_EXITED_THREADS_SAFE.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog
2015-04-07 Pedro Alves <palves@redhat.com>
* gdbthread.h (ALL_NON_EXITED_THREADS_SAFE): Rename to ...
(ALL_THREADS_SAFE): ... this, and don't skip exited threads.
(delete_exited_threads): New declaration.
* infrun.c (follow_exec): Use ALL_THREADS_SAFE.
* linux-nat.c (linux_nat_update_thread_list): New function.
(linux_nat_add_target): Install it.
* remote.c (remote_update_thread_list): Use ALL_THREADS_SAFE.
* thread.c (prune_threads): Use ALL_THREADS_SAFE.
(delete_exited_threads): New function.
Although not currently possible in practice when we get here,
'resume_ptid' can also be a wildcard throughout this function. It's
clearer to fetch the regcache using the thread's ptid.
gdb/ChangeLog:
2015-04-07 Pedro Alves <pedro@codesourcery.com>
* infrun.c (resume) <displaced stepping debug output>: Get the
leader thread's regcache, not resume_ptid's.
Nowadays, the alarm value is 60, and alarm is generated on some slow
boards. This patch is to pass DejaGNU timeout value to the program,
and move the alarm call before going to infinite loop. If any thread
has activities, the alarm is reset.
gdb/testsuite:
2015-04-07 Yao Qi <yao.qi@linaro.org>
* gdb.threads/non-stop-fair-events.c (SECONDS): New macro.
(child_function): Call alarm.
(main): Move call to alarm into the loop.
* gdb.threads/non-stop-fair-events.exp: Build program with
-DTIMEOUT=$timeout.
The "dest" parameter to fpc_compile/gpc_compile is the name of
compilation destination file, not a board name.
This patch fixes this by using names consistent with
lib/future.exp:gdb_default_target_compile.
gdb/testsuite/ChangeLog:
* lib/pascal.exp (gpc_compile): Rename dest arg to destfile.
Fix dest parameter to board_info.
(fpc_compile): Ditto.
(gdb_compile_pascal): Rename dest arg to destfile.
gdb/ChangeLog:
* symtab.c (hash_symbol_entry): Hash STRUCT_DOMAIN symbols as
VAR_DOMAIN.
(symbol_cache_lookup): Clarify use of bsc_ptr, slot_ptr parameters.
Include symbol domain in debugging output.
Currently building gdb is impossible without an installed termcap or
curses library. But, GDB already has a very minimal termcap in the
tree to handle this situation for Windows -- gdb/stub-termcap.c. This
patch makes that the fallback for all hosts.
Testing this on GNU/Linux (by simply hacking away the termcap/curses
detection in gdb/configure.ac), we trip on:
../readline/libreadline.a(terminal.o): In function `_rl_init_terminal_io':
/home/pedro/gdb/mygit/src/readline/terminal.c:527: undefined reference to `PC'
/home/pedro/gdb/mygit/src/readline/terminal.c:528: undefined reference to `BC'
/home/pedro/gdb/mygit/src/readline/terminal.c:529: undefined reference to `UP'
/home/pedro/gdb/mygit/src/readline/terminal.c:538: undefined reference to `PC'
/home/pedro/gdb/mygit/src/readline/terminal.c:539: undefined reference to `BC'
/home/pedro/gdb/mygit/src/readline/terminal.c:540: undefined reference to `UP'
These are globals that are normally defined by termcap (or ncurses'
termcap emulation).
Now, we could just define replacements in stub-termcap.c, but
readline/terminal.c (at least the copy in our tree) has this:
#if !defined (__linux__) && !defined (NCURSES_VERSION)
# if defined (__EMX__) || defined (NEED_EXTERN_PC)
extern
# endif /* __EMX__ || NEED_EXTERN_PC */
char PC, *BC, *UP;
#endif /* !__linux__ && !NCURSES_VERSION */
which can result in readline defining the globals too. That will
usually work out in C, given that "-fcommon" is usually the default
for C compilers, but that won't work for C++, or C with -fno-common
(link fails with "multiple definition" errors)...
Mirroring those #ifdef conditions in the stub termcap screams
"brittle" to me -- I can see them changing in latter readline
versions.
Work around that by simply using __attribute__((weak)).
Windows/PE/COFF's do support weak, but not on gcc 3.4 based toolchains
(4.8.x does work). Given the file never needed the variables while it
was Windows-only, just continue not defining them there. All other
supported hosts should support this.
gdb/ChangeLog:
2015-04-06 Pedro Alves <palves@redhat.com>
Bernd Edlinger <bernd.edlinger@hotmail.de>
* configure.ac: Remove the mingw32-specific stub-termcap.o
fallback, and instead fallback to the stub termcap on all hosts.
* configure: Regenerate.
* stub-termcap.c [!__MINGW32__] (PC, BC, UP): Define as weak
symbols.
This paramater is no longer useful after the previous commit, so remove
it as a cleanup.
gdb/ChangeLog:
* gdbtypes.c (is_dynamic_type_internal): Remove the unused
"top_level" parameter.
(resolve_dynamic_type_internal): Remove the unused "top_level"
parameter. Update call to is_dynamic_type_internal.
(is_dynamic_type): Update call to is_dynamic_type_internal.
(resolve_dynamic_range): Update call to
resolve_dynamic_type_internal.
(resolve_dynamic_union): Likewise.
(resolve_dynamic_struct): Likewise.
(resolve_dynamic_type): Likewise.
Even when referenced types are dynamic, the corresponding referencing
type should not be considered as dynamic: it's only a pointer. This
prevents reference type for values not in memory to be resolved.
gdb/ChangeLog:
* gdbtypes.c (is_dynamic_type_internal): Remove special handling
of TYPE_CODE_REF types so that they are not considered as
dynamic depending on the referenced type.
(resolve_dynamic_type_internal): Likewise.
gdb/testsuite/ChangeLog:
* gdb.ada/funcall_ref.exp: New file.
* gdb.ada/funcall_ref/foo.adb: New file.
I see these two fails in no-unwaited-for-left.exp in remote testing
for aarch64-linux target.
...
continue
Continuing.
warning: Remote failure reply: E.No unwaited-for children left.
[Thread 1084] #2 stopped.
(gdb) FAIL: gdb.threads/no-unwaited-for-left.exp: continue stops when thread 2 exits
....
continue
Continuing.
warning: Remote failure reply: E.No unwaited-for children left.
[Thread 1081] #1 stopped.
(gdb) FAIL: gdb.threads/no-unwaited-for-left.exp: continue stops when the main thread exits
I checked the gdb.log on buildbot, and find that these two fails also
appear on Debian-i686-native-extended-gdbserver and Fedora-ppc64be-native-gdbserver-m64.
I recall that they are about local/remote parity, and related RSP is missing.
There has been already a PR 14618 about it. This patch is to kfail them
on remote target.
gdb/testsuite:
2015-04-02 Yao Qi <yao.qi@linaro.org>
* gdb.threads/no-unwaited-for-left.exp: Set up kfail if target
is remote.
Stan Shebs
John Baldwin
Luis Machado
Yao Qi
Sergio Durigan Junior
Jan Kratochvil
Pedro Alves
Gary Benson
Andy Wingo
H.J. Lu
Doug Evans
Pierre-Marie de Rodat