Wanting to make sure the new continue-pending-status.exp test tests
both cases of threads 2 and 3 reporting an event, I added counters to
the test, to make it FAIL if events for both threads aren't seen.
Assuming a well behaved backend, and given a reasonable number of
iterations, it should PASS.
However, running that against GNU/Linux gdbserver, I found that
surprisingly, that FAILed. GDBserver always reported the breakpoint
hit for the same thread.
Turns out that I broke gdbserver's thread event randomization
recently, with git commit 582511be ([gdbserver] linux-low.c: better
starvation avoidance, handle non-stop mode too). In that commit I
missed that the thread structure also has a status_pending_p field...
The end result was that count_events_callback always returns 0, and
then if no thread is stepping, select_event_lwp always returns the
event thread. IOW, no randomization is happening at all. Quite
curious how all the other changes in that patch were sufficient to fix
non-stop-fair-events.exp anyway even with that broken.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/gdbserver/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* linux-low.c (count_events_callback, select_event_lwp_callback):
Use the lwp's status_pending_p field, not the thread's.
gdb/testsuite/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* gdb.threads/continue-pending-status.exp (saw_thread_2)
(saw_thread_3): New globals.
(top level): Increment them when an event for the corresponding
thread is seen.
(no thread starvation): New test.
If the linux_nat_resume's short-circuits the resume because the
current thread has a pending status, and, a thread with a higher
number was previously stopped for a breakpoint, GDB internal errors,
like:
/home/pedro/gdb/mygit/src/gdb/linux-nat.c:2590: internal-error: status_callback: Assertion `lp->status != 0' failed.
Fix this by make status_callback bail out earlier. GDBserver is
already doing the same.
New test added that exercises this.
gdb/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* linux-nat.c (status_callback): Return early if the LWP has no
status pending.
gdb/testsuite/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* gdb.threads/continue-pending-status.c: New file.
* gdb.threads/continue-pending-status.exp: New file.
This fixes several problems with this test.
E.g,. with --target_board=native-extended-gdbserver on x86_64 Fedora
20, I get:
Running /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/disp-step-syscall.exp ...
FAIL: gdb.base/disp-step-syscall.exp: vfork: get hexadecimal valueof "$pc" (timeout)
FAIL: gdb.base/disp-step-syscall.exp: vfork: single step over vfork final pc
FAIL: gdb.base/disp-step-syscall.exp: vfork: delete break vfork insn
FAIL: gdb.base/disp-step-syscall.exp: vfork: continue to marker (vfork) (the program is no longer running)
And with --target=native-gdbserver, I get:
Running /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/disp-step-syscall.exp ...
KPASS: gdb.base/disp-step-syscall.exp: vfork: single step over vfork (PRMS server/13796)
FAIL: gdb.base/disp-step-syscall.exp: vfork: get hexadecimal valueof "$pc" (timeout)
FAIL: gdb.base/disp-step-syscall.exp: vfork: single step over vfork final pc
FAIL: gdb.base/disp-step-syscall.exp: vfork: delete break vfork insn
FAIL: gdb.base/disp-step-syscall.exp: vfork: continue to marker (vfork) (the program is no longer running)
First, the lack of fork support on remote targets is supposed to be
kfailed, so the KPASS is obviously bogus. The extended-remote board
should have KFAILed too.
The problem is that the test is using "is_remote" instead of
gdb_is_target_remote.
And then, I get:
(gdb) PASS: gdb.base/disp-step-syscall.exp: vfork: set displaced-stepping on
stepi
Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb) PASS: gdb.base/disp-step-syscall.exp: vfork: single step over vfork
Obviously, that should be a FAIL. The problem is that the test only
expects SIGILL, not SIGSEGV. It also doesn't bail correctly if an
internal error or some other pattern caught by gdb_test_multiple
matches. The test doesn't really need to match specific exits/crashes
patterns, if the PASS regex is improved, like in ...
... this and the other "stepi" tests are a bit too lax, passing on
".*". This tightens those up to expect "x/i" and the "=>" current PC
indicator, like in:
1: x/i $pc
=> 0x3b36abc9e2 <vfork+34>: syscall
On x86_64 Fedora 20, I now get a quick KFAIL instead of timeouts with
both the native-extended-gdbserver and native-gdbserver boards:
PASS: gdb.base/disp-step-syscall.exp: vfork: delete break vfork
PASS: gdb.base/disp-step-syscall.exp: vfork: continue to syscall insn vfork
PASS: gdb.base/disp-step-syscall.exp: vfork: set displaced-stepping on
KFAIL: gdb.base/disp-step-syscall.exp: vfork: single step over vfork (PRMS: server/13796)
and a full pass with native testing.
gdb/testsuite/
2015-03-18 Pedro Alves <palves@redhat.com>
* gdb.base/disp-step-syscall.exp (disp_step_cross_syscall):
Use gdb_is_target_remote instead of is_remote. Use
gdb_test_multiple instead of gdb_expect. Exit early if
gdb_test_multiple hits its internal matches. Tighten stepi tests
expected output. Fail on exit with any signal, instead of just
SIGILL.
Hi,
This patch is to support catch syscall on aarch64 linux. We
implement gdbarch method get_syscall_number for aarch64-linux,
and add aarch64-linux.xml file, which looks straightforward, however
the changes to test case doesn't.
First of all, we enable catch-syscall.exp on aarch64-linux target,
but skip the multi_arch testing on current stage. I plan to touch
multi arch debugging on aarch64-linux later.
Then, when I run catch-syscall.exp on aarch64-linux, gcc errors that
SYS_pipe isn't defined. We find that aarch64 kernel only has pipe2
syscall and libc already convert pipe to pipe2. As a result, I change
catch-syscall.c to use SYS_pipe if it is defined, otherwise use
SYS_pipe2 instead. The vector all_syscalls in catch-syscall.exp can't
be pre-determined, so I add a new proc setup_all_syscalls to fill it,
according to the availability of SYS_pipe.
Regression tested on {x86_64, aarch64}-linux x {native, gdbserver}.
gdb:
2015-03-18 Yao Qi <yao.qi@linaro.org>
PR tdep/18107
* aarch64-linux-tdep.c: Include xml-syscall.h
(aarch64_linux_get_syscall_number): New function.
(aarch64_linux_init_abi): Call
set_gdbarch_get_syscall_number.
* syscalls/aarch64-linux.xml: New file.
gdb/testsuite:
2015-03-18 Yao Qi <yao.qi@linaro.org>
PR tdep/18107
* gdb.base/catch-syscall.c [!SYS_pipe] (pipe2_syscall): New
variable.
* gdb.base/catch-syscall.exp: Don't skip it on
aarch64*-*-linux* target. Remove elements in all_syscalls.
(test_catch_syscall_multi_arch): Skip it on aarch64*-linux*
target.
(setup_all_syscalls): New proc.
We see some fails in watchpoint-reuse-slot.exp on aarch64-linux, because
it sets some HW breakpoint on some address doesn't meet the alignment
requirements by kernel, kernel will reject the
ptrace (PTRACE_SETHBPREGS) call, and some fails are caused, for example:
(gdb) PASS: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x hbreak: : width 1, iter 0: base + 0: delete $bpnum
hbreak *(buf.byte + 0 + 1)^M
Hardware assisted breakpoint 80 at 0x410a61^M
(gdb) PASS: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x hbreak: : width 1, iter 0: base + 1: hbreak *(buf.byte + 0 + 1)
stepi^M
Warning:^M
Cannot insert hardware breakpoint 80.^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 hbreak: : width 1, iter 0: base + 1: stepi advanced
hbreak *(buf.byte + 0 + 1)^M
Hardware assisted breakpoint 440 at 0x410a61^M
Warning:^M
Cannot insert hardware breakpoint 440.^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 hbreak: : width 1, iter 0: base + 1: hbreak *(buf.byte + 0 + 1)
This patch is to skip some tests by checking proc valid_addr_p.
We can handle other targets in valid_addr_p too.
gdb/testsuite:
2015-03-16 Yao Qi <yao.qi@linaro.org>
* gdb.base/watchpoint-reuse-slot.exp (valid_addr_p): New proc.
(top level): Skip tests if valid_addr_p returns false for
$cmd1 or $cmd2.
Unfortunately, the Python version of the dg-extract-results.sh script
doesn't produce stable-enough results for GDB. The test messages
appear to end up alpha sorted (losing the original sequence) and also
sorting changes between runs for some reason. That may be tolerable
for GCC, but for GDB, it often renders test results diffing between
different revisions unworkable.
Until that is fixed upstream, delete the script from the GDB tree.
testsuite/ChangeLog:
2015-03-09 Pedro Alves <palves@redhat.com>
* dg-extract-results.py: Delete.
This merges Sergio's fix from GCC:
https://gcc.gnu.org/ml/gcc-patches/2014-12/msg01293.html
gdb/testsuite/ChangeLog:
2015-03-09 Pedro Alves <palves@redhat.com>
Merge dg-extract-results.sh from GCC upstream (r218843).
2014-12-17 Sergio Durigan Junior <sergiodj@redhat.com>
* dg-extract-results.sh: Use --text with grep to avoid issues with
binary files. Fall back to cat -v, if that doesn't work.
Trying to fix a permanent breakpoints bug, I broke "next" over a
regular breakpoint. "next" would immediately hit the breakpoint the
program was already stopped at. But, the "next over setup" test
failed to notice this and still issued a pass. That's because the
regex matches "testsuite" in:
Breakpoint 2 at 0x400687: file src/gdb/testsuite/gdb.base/bp-permanent.c, line 46.
gdb/testsuite/ChangeLog:
2015-03-05 Pedro Alves <palves@redhat.com>
* gdb.base/bp-permanent.exp: Tighten "next over setup" regex.
When interrupting a thread in non-stop vs all-stop, the signal given in
the MI *stopped event is not the same. Currently, mi_expect_interrupt only
accepts the case for non-stop, so this adds the alternative for all-stop.
gdb/testsuite/ChangeLog:
* lib/mi-support.exp (mi_expect_interrupt): Accept
alternative event for when in all-stop mode.
Gary stumbled on this:
(gdb) PASS: gdb.threads/thread-specific-bp.exp: all-stop: continue to end
info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fdb700 (LWP 13717) "thread-specific" end () at /home/gary/work/archer/startswith/src/gdb/testsuite/gdb.threads/thread-specific-bp.c:29
(gdb) FAIL: gdb.threads/thread-specific-bp.exp: all-stop: thread start is gone
info breakpoint
The problem is that "...archer/startswith/src..." has a "start" in it,
which matches the too-lax regex in the test.
Rather than tweaking the regex, we can just remove the whole "info
threads", like we removed similar ones in other files -- GDB nowadays
does this implicitly already, so things should work without it. Thus
removing this even improves testing here a bit.
gdb/testsuite/ChangeLog:
2015-03-04 Pedro Alves <palves@redhat.com>
* gdb.threads/thread-specific-bp.exp: Delete "info threads" test.
On some targets each of the assignments "i = 0" in the C source for
"breakpoint-in-ro-region.exp" are compiled to a single instruction.
Then each "si" stops at the beginning of the next source line. But on
some other targets (like s390) such an assignment compiles to multiple
instructions. Then "si" may stop in mid-line, and GDB displays the PC
address in addition to the source line number. This was not considered
by the regexp for this case.
gdb/testsuite/ChangeLog:
* gdb.base/breakpoint-in-ro-region.exp (test_single_step): In the
regexps for GDB's current line display, accept a hex address
preceding the line number.
For the "multiple targets" test in catch-syscall.exp, set the 'arch1'
variable to a valid string.
gdb/testsuite/ChangeLog:
* gdb.base/catch-syscall.exp (test_catch_syscall_multi_arch): Set
the 'arch1' variable for "s390*-linux*" targets.
This fixes:
> gdb compile failed, /gdb/testsuite/gdb.threads/clone-thread_db.c: In function 'main':
> /gdb/testsuite/gdb.threads/clone-thread_db.c:67:3: warning: implicit declaration of function 'alarm' [-Wimplicit-function-declaration]
> alarm (300);
> ^
> /gdb/testsuite/gdb.threads/clone-thread_db.c:69:3: warning: implicit declaration of function 'pthread_create' [-Wimplicit-function-declaration]
> pthread_create (&child, NULL, thread_fn, NULL);
> ^
> /gdb/testsuite/gdb.threads/clone-thread_db.c:70:3: warning: implicit declaration of function 'pthread_join' [-Wimplicit-function-declaration]
> pthread_join (child);
> ^
And then adding the missing headers revealed the pthread_join call was
incorrect. This probably fixes the crash we see on ppc64be, e.g., at
https://sourceware.org/ml/gdb-testers/2015-q1/msg04415.html
the logs there show:
...
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x3fffb7ff54a0 (LWP 9275)]
0x00003fffb7f3ce74 in .pthread_join () from /lib64/libpthread.so.0
(gdb) FAIL: gdb.threads/clone-thread_db.exp: continue to end
...
Tested on x86_64 Fedora 20.
gdb/testsuite/
2015-03-04 Pedro Alves <palves@redhat.com>
* gdb.threads/clone-thread_db.c: Include unistd.h and pthread.h.
(main): Pass missing retval argument to pthread_join call.
This fixes invalid reads Valgrind first caught when debugging against
a GDBserver patched with a series that adds exec events to the remote
protocol. Like these, using the gdb.threads/thread-execl.exp test:
$ valgrind ./gdb -data-directory=data-directory ./testsuite/gdb.threads/thread-execl -ex "tar extended-remote :9999" -ex "b thread_execler" -ex "c" -ex "set scheduler-locking on"
...
Breakpoint 1, thread_execler (arg=0x0) at src/gdb/testsuite/gdb.threads/thread-execl.c:29
29 if (execl (image, image, NULL) == -1)
(gdb) n
Thread 32509.32509 is executing new program: build/gdb/testsuite/gdb.threads/thread-execl
[New Thread 32509.32532]
==32510== Invalid read of size 4
==32510== at 0x5AA7D8: delete_breakpoint (breakpoint.c:13989)
==32510== by 0x6285D3: delete_thread_breakpoint (thread.c:100)
==32510== by 0x628603: delete_step_resume_breakpoint (thread.c:109)
==32510== by 0x61622B: delete_thread_infrun_breakpoints (infrun.c:2928)
==32510== by 0x6162EF: for_each_just_stopped_thread (infrun.c:2958)
==32510== by 0x616311: delete_just_stopped_threads_infrun_breakpoints (infrun.c:2969)
==32510== by 0x616C96: fetch_inferior_event (infrun.c:3267)
==32510== by 0x63A2DE: inferior_event_handler (inf-loop.c:57)
==32510== by 0x4E0E56: remote_async_serial_handler (remote.c:11877)
==32510== by 0x4AF620: run_async_handler_and_reschedule (ser-base.c:137)
==32510== by 0x4AF6F0: fd_event (ser-base.c:182)
==32510== by 0x63806D: handle_file_event (event-loop.c:762)
==32510== Address 0xcf333e0 is 16 bytes inside a block of size 200 free'd
==32510== at 0x4A07577: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==32510== by 0x77CB74: xfree (common-utils.c:98)
==32510== by 0x5AA954: delete_breakpoint (breakpoint.c:14056)
==32510== by 0x5988BD: update_breakpoints_after_exec (breakpoint.c:3765)
==32510== by 0x61360F: follow_exec (infrun.c:1091)
==32510== by 0x6186FA: handle_inferior_event (infrun.c:4061)
==32510== by 0x616C55: fetch_inferior_event (infrun.c:3261)
==32510== by 0x63A2DE: inferior_event_handler (inf-loop.c:57)
==32510== by 0x4E0E56: remote_async_serial_handler (remote.c:11877)
==32510== by 0x4AF620: run_async_handler_and_reschedule (ser-base.c:137)
==32510== by 0x4AF6F0: fd_event (ser-base.c:182)
==32510== by 0x63806D: handle_file_event (event-loop.c:762)
==32510==
[Switching to Thread 32509.32532]
Breakpoint 1, thread_execler (arg=0x0) at src/gdb/testsuite/gdb.threads/thread-execl.c:29
29 if (execl (image, image, NULL) == -1)
(gdb)
The breakpoint in question is the step-resume breakpoint of the
non-main thread, the one that was "next"ed.
The exact same issue can be seen on mainline with native debugging, by
running the thread-execl.exp test in non-stop mode, because the kernel
doesn't report a thread exit event for the execing thread.
Tested on x86_64 Fedora 20.
gdb/ChangeLog:
2015-03-02 Pedro Alves <palves@redhat.com>
* infrun.c (follow_exec): Delete all threads of the process except
the event thread. Extended comments.
gdb/testsuite/ChangeLog:
2015-03-02 Pedro Alves <palves@redhat.com>
* gdb.threads/thread-execl.exp (do_test): Handle non-stop.
(top level): Call do_test with non-stop as well.
gdb_test_multiple is supposed to return -1 on internal error:
# Returns:
# 1 if the test failed, according to a built-in failure pattern
# 0 if only user-supplied patterns matched
# -1 if there was an internal error.
But alas, that's broken, it returns success... It looks like the code
is assuming an earlier 'set result -1' is still in effect, but
'result' is set to 0 at the end, just before we call gdb_expect:
set result 0
set code [catch {gdb_expect $code} string]
gdb/testsuite/
2015-03-02 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (gdb_test_multiple) <internal error>: Set result to
-1.
gdb/testsuite/
2015-02-27 Pedro Alves <palves@redhat.com>
* gdb.gdb/complaints.exp (test_initial_complaints): Also accept
"true" for boolean result.
* gdb.gdb/selftest.exp (test_with_self): Also accept full
prototype of main.
In some scenarios, GDB or GDBserver can be spawned with input _not_
connected to a tty, and then tests that rely on stdio fail with
timeouts, because the inferior's stdout and stderr streams end up
fully buffered.
See discussion here:
https://sourceware.org/ml/gdb-patches/2015-02/msg00809.html
We have a hack in place that works around this for Windows testing,
that forces every test program to link with an .o file that does
(lib/set_unbuffered_mode.c):
static int __gdb_set_unbuffered_output (void) __attribute__ ((constructor));
static int
__gdb_set_unbuffered_output (void)
{
setvbuf (stdout, NULL, _IONBF, BUFSIZ);
setvbuf (stderr, NULL, _IONBF, BUFSIZ);
}
That's a bit hacky; it ends up done for _all_ tests.
This patch adds a way to do this unbuffering explicitly from the test
code itself, so it is done only when necessary, and for all
targets/hosts. For starters, it adjusts gdb.base/interrupt.c to use
it.
Tested on x86_64 Fedora 20, native, and against a remote gdbserver
board file that connects to the target with ssh, with and without -t
(create pty).
gdb/testsuite/
2015-02-27 Pedro Alves <palves@redhat.com>
* lib/unbuffer_output.c: New file.
* gdb.base/interrupt.c: Include "../lib/unbuffer_output.c".
(main): Call gdb_unbuffer_output.
As far as I know, "catch syscall" is supported on hppa*-hp-hpux*, but
the test catch-syscall.exp is skipped on this target by mistake. This
patch is to fix it. However, I don't have a hpux machine to test.
gdb/testsuite:
2015-02-27 Yao Qi <yao.qi@linaro.org>
* gdb.base/catch-syscall.exp: Don't skip it on hppa*-hp-hpux*
target.
One could not call IFUNCs (=indirect functions) from the compiled injected
code. Either it errored with:
gdb command line:1:1: error: function return type cannot be function
or it just called the IFUNC dispatcher in normal way, returning real function
implementation address instead of the function return value (and thus no
function was called).
gdb/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile-c-symbols.c (convert_one_symbol, convert_symbol_bmsym)
(gcc_symbol_address): Call gnu_ifunc_resolve_addr.
gdb/testsuite/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.compile/compile-ifunc.c: New file.
* gdb.compile/compile-ifunc.exp: New file.
When doing finish in a function, if gdb fails to return a value, gdb
also fails at printing the value type if this type is a struct.
For example :
(gdb) fin
....
Value returned has type: . Cannot determine contents
This patch fixes this by calling type_to_string to print the type
so that we can support these types.
This patch returns the following example output :
(gdb) fin
....
Value returned has type: struct test. Cannot determine contents
Also, this patch modifies structs.exp to check that we return the
correct type.
gdb/ChangeLog:
* gdb/infcmd.c (print_return_value): use type_to_string to print type.
gdb/testsuite/ChangeLog:
* gdb.base/structs.exp: Check for correct struct on finish.
On aarch64, we got the following fail:
(gdb) disassemble func
Dump of assembler code for function func:
0x0000000000400730 <+0>: ret
End of assembler dump.^M
(gdb) x/2i func+0^M
0x400730 <func>: ret^M
0x400734 <main>: stp x29, x30, [sp,#-16]!^M
(gdb) FAIL: gdb.dwarf2/dw2-ifort-parameter.exp: x/2i func+0
the pattern in proc function_range expects to match <func+0>, however,
GDB doesn't display the offset when it is zero. This patch is to
adjust the pattern when $func_length is zero.
gdb/testsuite:
2015-02-26 Yao Qi <yao.qi@linaro.org>
* lib/dwarf.exp (function_range): Adjust pattern when $func_length
is zero.
The attached patch fixes the SEGV and lets GDB successfully
load all kernel modules installed by default on RHEL 7.
Valgrind on F-21 x86_64 host has shown me more clear what is the problem:
Reading symbols from /home/jkratoch/t/cordic.ko...Reading symbols from
/home/jkratoch/t/cordic.ko.debug...=================================================================
==22763==ERROR: AddressSanitizer: heap-use-after-free on address 0x6120000461c8 at pc 0x150cdbd bp 0x7fffffffc7e0 sp 0x7fffffffc7d0
READ of size 8 at 0x6120000461c8 thread T0
#0 0x150cdbc in ppc64_elf_get_synthetic_symtab /home/jkratoch/redhat/gdb-test-asan/bfd/elf64-ppc.c:3282
#1 0x8c5274 in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1205
#2 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
0x6120000461c8 is located 264 bytes inside of 288-byte region [0x6120000460c0,0x6120000461e0)
freed by thread T0 here:
#0 0x7ffff715454f in __interceptor_free (/lib64/libasan.so.1+0x5754f)
#1 0xde9cde in xfree common/common-utils.c:98
#2 0x9a04f7 in do_my_cleanups common/cleanups.c:155
#3 0x9a05d3 in do_cleanups common/cleanups.c:177
#4 0x8c538a in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1229
#5 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
previously allocated by thread T0 here:
#0 0x7ffff71547c7 in malloc (/lib64/libasan.so.1+0x577c7)
#1 0xde9b95 in xmalloc common/common-utils.c:41
#2 0x8c4da2 in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1147
#3 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
SUMMARY: AddressSanitizer: heap-use-after-free /home/jkratoch/redhat/gdb-test-asan/bfd/elf64-ppc.c:3282 ppc64_elf_get_synthetic_symtab
[...]
==22763==ABORTING
A similar case a few lines later I have fixed in 2010 by:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=3f1eff0a2c7f0e7078f011f55b8e7f710aae0cc2
My testcase does not always reproduce it but at least a bit:
* GDB without ppc64 target (even as a secondary one) is reported as "untested"
* ASAN-built GDB with ppc64 target always crashes (and PASSes with this fix)
* unpatched non-ASAN-built GDB with ppc64 target crashes from commandline
* unpatched non-ASAN-built GDB with ppc64 target PASSes from runtest (?)
gdb/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* elfread.c (elf_read_minimal_symbols): Use bfd_alloc for
bfd_canonicalize_symtab.
gdb/testsuite/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.arch/cordic.ko.bz2: New file.
* gdb.arch/cordic.ko.debug.bz2: New file.
* gdb.arch/ppc64-symtab-cordic.exp: New file.
Hi,
I see the following fail in aarch64-linux-gnu testing...
(gdb) set tdesc file /XXX/gdb/testsuite/gdb.xml/single-reg.xml^M
warning: Architecture rejected target-supplied description^M
(gdb) FAIL: gdb.xml/tdesc-regs.exp: set tdesc file single-reg.xml
core-regs isn't set for aarch64 target, and looks it is an oversight
when aarch64 port was added.
gdb/testsuite:
2015-02-25 Yao Qi <yao.qi@linaro.org>
* gdb.xml/tdesc-regs.exp: Set core-regs to aarch64-core.xml for
aarch64*-*-* target.
Because delete_breakpoints uses gdb_expect directly, an internal error
results in slow timeouts instead of quickly bailing out. This patch
rewrites the procedure to use gdb_test_multiple instead, while
preserving the existing general logic ("delete breakpoints" + "info
breakpoints").
gdb/testsuite/
2015-02-23 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (delete_breakpoints): Rewrite using
gdb_test_multiple.
Fixes:
> gdb compile failed, /gdb/testsuite/gdb.base/info-os.c: In function 'main':
> /gdb/testsuite/gdb.base/info-os.c:65:3: warning: implicit declaration of function 'atexit' [-Wimplicit-function-declaration]
> atexit (ipc_cleanup);
> ^
> FAIL: gdb.base/info-os.exp: cannot compile test program
with recent GCCs.
gdb/testsuite/ChangeLog:
2015-02-23 Pedro Alves <palves@redhat.com>
* gdb.base/info-os.c: Include stdlib.h.
gdb/testsuite/ChangeLog:
PR symtab/17855
* gdb.ada/exec_changed.exp: Add second test where symbol lookup cache
is read after symbols have been re-read.
* gdb.ada/exec_changed/first.adb (First): New procedure Break_Me.
* gdb.ada/exec_changed/second.adb (Second): Ditto.
This patch addresses two issues.
The basic problem is that "(anonymous namespace)" doesn't get entered
into the symbol table because when dwarf2read.c:new_symbol_full is called
the DIE has no name (dwarf2_name returns NULL).
PR 17976: ptype '(anonymous namespace)' should work like any namespace
PR 17821: perf issue looking up (anonymous namespace)
bash$ gdb monster-program
(gdb) mt set per on
(gdb) mt set symbol-cache-size 0
(gdb) break (anonymous namespace)::foo
Before:
Command execution time: 3.266289 (cpu), 6.169030 (wall)
Space used: 811429888 (+12910592 for this command)
After:
Command execution time: 1.264076 (cpu), 4.057408 (wall)
Space used: 798781440 (+0 for this command)
gdb/ChangeLog:
PR c++/17976, symtab/17821
* cp-namespace.c (cp_search_static_and_baseclasses): New parameter
is_in_anonymous. All callers updated.
(find_symbol_in_baseclass): Ditto.
(cp_lookup_nested_symbol_1): Ditto. Don't search all static blocks
for symbols in an anonymous namespace.
* dwarf2read.c (namespace_name): Don't call dwarf2_name, fetch
DW_AT_name directly.
(dwarf2_name): Convert missing namespace name to
CP_ANONYMOUS_NAMESPACE_STR.
gdeb/testsuite/ChangeLog:
* gdb.cp/anon-ns.exp: Add test for ptype '(anonymous namespace)'.
gdb/testsuite/ChangeLog
2015-02-21 Jan Kratochvil <jan.kratochvil@redhat.com>
PR corefiles/17808
* gdb.arch/i386-biarch-core.core.bz2: New file.
* gdb.arch/i386-biarch-core.exp: New file.
The buildbot shows that the new
gdb.threads/multi-create-ns-info-thr.exp test is timing out when
tested with --target=native-extended-remote. The reason is:
No breakpoints or watchpoints.
(gdb) break main
Breakpoint 1 at 0x10000b00: file ../../../binutils-gdb/gdb/testsuite/gdb.threads/multi-create.c, line 72.
(gdb) run
Starting program: /home/gdb-buildbot/fedora-21-ppc64be-1/fedora-ppc64be-native-extended-gdbserver/build/gdb/testsuite/outputs/gdb.threads/multi-create-ns-info-thr/multi-cre
ate-ns-info-thr
Process /home/gdb-buildbot/fedora-21-ppc64be-1/fedora-ppc64be-native-extended-gdbserver/build/gdb/testsuite/outputs/gdb.threads/multi-create-ns-info-thr/multi-create-ns-inf
o-thr created; pid = 16266
Unexpected vCont reply in non-stop mode: T0501:00003fffffffd190;40:00000080560fe290;thread:p3f8a.3f8a;core:0;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(gdb) break multi-create.c:45
Breakpoint 2 at 0x10000994: file ../../../binutils-gdb/gdb/testsuite/gdb.threads/multi-create.c, line 45.
(gdb) commands
Type commands for breakpoint(s) 2, one per line.
Non-stop tests don't really work with the
--target_board=native-extended-remote board, because tests toggle
non-stop on after GDB is already connected to gdbserver, while
Currently, non-stop must be enabled before connecting.
This adjusts the test to bail if running to main fails, like all other
non-stop tests.
Note non-stop tests do work with --target_board=native-gdbserver.
gdb/testsuite/ChangeLog:
2015-02-21 Pedro Alves <palves@redhat.com>
* gdb.threads/multi-create-ns-info-thr.exp: Return early if
runto_main fails.
Commit 6f9b8491 (Adapt `info probes' to support printing probes of
different types.) added a new type column to "info probes". That
caused a solib-corrupted.exp regression:
~~~~~~~~~~~~~~~~~~~~~
Running /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/solib-corrupted.exp ...
FAIL: gdb.base/solib-corrupted.exp: corrupted list
=== gdb Summary ===
# of expected passes 2
# of unexpected failures 1
~~~~~~~~~~~~~~~~~~~~~
Tested on x86_64 Fedora 20.
gdb/testsuite/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* gdb.base/solib-corrupted.exp: Expect "stap" as first column of
info probes.
TL;DR - GDB can hang if something refreshes the thread list out of the
target while the target is running. GDB hangs inside td_ta_thr_iter.
The fix is to not use that libthread_db function anymore.
Long version:
Running the testsuite against my all-stop-on-top-of-non-stop series is
still exposing latent non-stop bugs.
I was originally seeing this with the multi-create.exp test, back when
we were still using libthread_db thread event breakpoints. The
all-stop-on-top-of-non-stop series forces a thread list refresh each
time GDB needs to start stepping over a breakpoint (to pause all
threads). That test hits the thread event breakpoint often, resulting
in a bunch of step-over operations, thus a bunch of thread list
refreshes while some threads in the target are running.
The commit adds a real non-stop mode test that triggers the issue,
based on multi-create.exp, that does an explicit "info threads" when a
breakpoint is hit. IOW, it does the same things the as-ns series was
doing when testing multi-create.exp.
The bug is a race, so it unfortunately takes several runs for the test
to trigger it. In fact, even when setting the test running in a loop,
it sometimes takes several minutes for it to trigger for me.
The race is related to libthread_db's td_ta_thr_iter. This is
libthread_db's entry point for walking the thread list of the
inferior.
Sometimes, when GDB refreshes the thread list from the target,
libthread_db's td_ta_thr_iter can somehow see glibc's thread list as a
cycle, and get stuck in an infinite loop.
The issue is that when a thread exits, its thread control structure in
glibc is moved from a "used" list to a "cache" list. These lists are
simply circular linked lists where the "next/prev" pointers are
embedded in the thread control structure itself. The "next" pointer
of the last element of the list points back to the list's sentinel
"head". There's only one set of "next/prev" pointers for both lists;
thus a thread can only be in one of the lists at a time, not in both
simultaneously.
So when thread C exits, simplifying, the following happens. A-C are
threads. stack_used and stack_cache are the list's heads.
Before:
stack_used -> A -> B -> C -> (&stack_used)
stack_cache -> (&stack_cache)
After:
stack_used -> A -> B -> (&stack_used)
stack_cache -> C -> (&stack_cache)
td_ta_thr_iter starts by iterating at the list's head's next, and
iterates until it sees a thread whose next pointer points to the
list's head again. Thus in the before case above, C's next points to
stack_used, indicating end of list. In the same case, the stack_cache
list is empty.
For each thread being iterated, td_ta_thr_iter reads the whole thread
object out of the inferior. This includes the thread's "next"
pointer.
In the scenario above, it may happen that td_ta_thr_iter is iterating
thread B and has already read B's thread structure just before thread
C exits and its control structure moves to the cached list.
Now, recall that td_ta_thr_iter is running in the context of GDB, and
there's no locking between GDB and the inferior. From it's local copy
of B, td_ta_thr_iter believes that the next thread after B is thread
C, so it happilly continues iterating to C, a thread that has already
exited, and is now in the stack cache list.
After iterating C, td_ta_thr_iter finds the stack_cache head, which
because it is not stack_used, td_ta_thr_iter assumes it's just another
thread. After this, unless the reverse race triggers, GDB gets stuck
in td_ta_thr_iter forever walking the stack_cache list, as no thread
in thatlist has a next pointer that points back to stack_used (the
terminating condition).
Before fully understanding the issue, I tried adding cycle detection
to GDB's td_ta_thr_iter callback. However, td_ta_thr_iter skips
calling the callback in some cases, which means that it's possible
that the callback isn't called at all, making it impossible for GDB to
break the loop. I did manage to get GDB stuck in that state more than
once.
Fortunately, we can avoid the issue altogether. We don't really need
td_ta_thr_iter for live debugging nowadays, given PTRACE_EVENT_CLONE.
We already know how to map and lwp id to a thread id without iterating
(thread_from_lwp), so use that more.
gdb/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* linux-nat.c (linux_handle_extended_wait): Call
thread_db_notice_clone whenever a new clone LWP is detected.
(linux_stop_and_wait_all_lwps, linux_unstop_all_lwps): New
functions.
* linux-nat.h (thread_db_attach_lwp): Delete declaration.
(thread_db_notice_clone, linux_stop_and_wait_all_lwps)
(linux_unstop_all_lwps): Declare.
* linux-thread-db.c (struct thread_get_info_inout): Delete.
(thread_get_info_callback): Delete.
(thread_from_lwp): Use td_thr_get_info and record_thread.
(thread_db_attach_lwp): Delete.
(thread_db_notice_clone): New function.
(try_thread_db_load_1): If /proc is mounted and shows the
process'es task list, walk over all LWPs and call thread_from_lwp
instead of relying on td_ta_thr_iter.
(attach_thread): Don't call check_thread_signals here. Split the
tail part of the function (which adds the thread to the core GDB
thread list) to ...
(record_thread): ... this function. Call check_thread_signals
here.
(thread_db_wait): Don't call thread_db_find_new_threads_1. Always
call thread_from_lwp.
(thread_db_update_thread_list): Rename to ...
(thread_db_update_thread_list_org): ... this.
(thread_db_update_thread_list): New function.
(thread_db_find_thread_from_tid): Delete.
(thread_db_get_ada_task_ptid): Simplify.
* nat/linux-procfs.c: Include <sys/stat.h>.
(linux_proc_task_list_dir_exists): New function.
* nat/linux-procfs.h (linux_proc_task_list_dir_exists): Declare.
gdb/gdbserver/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* thread-db.c: Include "nat/linux-procfs.h".
(thread_db_init): Skip listing new threads if the kernel supports
PTRACE_EVENT_CLONE and /proc/PID/task/ is accessible.
gdb/testsuite/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* gdb.threads/multi-create-ns-info-thr.exp: New file.
$ make check RUNTESTFLAGS="--target_board=native-gdbserver no-attach-trace.exp"
...
(gdb) trace main
Tracepoint 1 at 0x400594: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.trace/no-attach-trace.c, line 25.
(gdb) PASS: gdb.trace/no-attach-trace.exp: set tracepoint on main
tstart
You can't do that when your target is `exec'
(gdb) FAIL: gdb.trace/no-attach-trace.exp: tstart
Even though this target supports tracing, the test restarts GDB and
doesn't do gdb_run_cmd so does not reconnect to the remote target. So
at that point, GDB only has the "exec" target, which obviously doesn't
do tracing.
The test is about doing "tstart" before running a program, so the fix
is to do gdb_target_supports_trace with whatever target GDB ends up
connected after clean_restart.
Tested on x86_64 Fedora 20, native, native-gdbserver and
native-extended-gdbserver boards. The test passes with the latter,
and is skipped with the first two.
gdb/testsuite/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* gdb.trace/no-attach-trace.exp: Don't run to main. Do
clean_restart before gdb_target_supports_trace.
On GNU/Linux, if a pthreaded program has a thread call clone(CLONE_VM)
directly, and then that clone LWP hits a debug event (breakpoint,
etc.) GDB internal errors. Threaded programs shouldn't really be
calling clone directly, but GDB shouldn't crash either.
The crash looks like this:
(gdb) break clone_fn
Breakpoint 2 at 0x4007d8: file clone-thread_db.c, line 35.
(gdb) r
...
[Thread debugging using libthread_db enabled]
...
src/gdb/linux-nat.c:1030: internal-error: lin_lwp_attach_lwp: Assertion `lwpid > 0' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
The problem is that 'clone' ends up clearing the parent thread's tid
field in glibc's thread data structure. For x86_64, the glibc code in
question is here:
sysdeps/unix/sysv/linux/x86_64/clone.S:
...
testq $CLONE_THREAD, %rdi
jne 1f
testq $CLONE_VM, %rdi
movl $-1, %eax <----
jne 2f
movl $SYS_ify(getpid), %eax
syscall
2: movl %eax, %fs:PID
movl %eax, %fs:TID <----
1:
When GDB refreshes the thread list out of libthread_db, it finds a
thread with LWP with pid -1 (the clone's parent), which naturally
isn't yet on the thread list. GDB then tries to attach to that bogus
LWP id, which is caught by that assertion.
The fix is to detect the bad PID early.
Tested on x86-64 Fedora 20. GDBserver doesn't need any fix.
gdb/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
PR threads/18006
* linux-thread-db.c (thread_get_info_callback): Return early if
the thread's lwp id is -1.
gdb/testsuite/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
PR threads/18006
* gdb.threads/clone-thread_db.c: New file.
* gdb.threads/clone-thread_db.exp: New file.
When gdb creates a dummy frame to execute a function in the inferior,
the process may generate a SIGSEGV, SIGTRAP or SIGILL because the stack
is non executable. If the signal handler set in gdb has option print
or stop enabled for these signals gdb handles this correctly.
However, in the case of noprint and nostop the signal is short-circuited
and the inferior process is sent the signal directly. This causes the
inferior to crash because of gdb.
This patch adds a check for SIGSEGV, SIGTRAP or SIGILL so that these
signals are sent to gdb rather than short-circuited in the inferior.
gdb then handles them properly and the inferior process does not
crash.
This patch also fixes the same behavior in gdbserver.
Also added a small testcase to test the issue called catch-gdb-caused-signals.
This applies to Linux only, tested on Linux.
gdb/ChangeLog:
PR breakpoints/16812
* linux-nat.c (linux_nat_filter_event): Report SIGTRAP,SIGILL,SIGSEGV.
* nat/linux-ptrace.c (linux_wstatus_maybe_breakpoint): Add.
* nat/linux-ptrace.h: Add linux_wstatus_maybe_breakpoint.
gdb/gdbserver/ChangeLog:
PR breakpoints/16812
* linux-low.c (wstatus_maybe_breakpoint): Remove.
(linux_low_filter_event): Update wstatus_maybe_breakpoint name.
(linux_wait_1): Report SIGTRAP,SIGILL,SIGSEGV.
gdb/testsuite/ChangeLog:
PR breakpoints/16812
* gdb.base/catch-gdb-caused-signals.c: New file.
* gdb.base/catch-gdb-caused-signals.exp: New file.
This patch introduces a new M4 macro GDB_AC_TRANSFORM to avoid repeating
the common idiom which is the transformation of target program names,
i.e. from gdb to sparc64-linux-gnu-gdb. It also makes gdb/configure.ac
and gdb/testsuite/configure.ac to use the new macro.
gdb/ChangeLog:
2015-02-18 Jose E. Marchesi <jose.marchesi@oracle.com>
* configure: Regenerated.
* configure.ac: Use GDB_AC_TRANSFORM.
* Makefile.in (aclocal_m4_deps): Added transform.m4.
* acinclude.m4: sinclude transform.m4.
* transform.m4: New file.
(GDB_AC_TRANSFORM): New macro.
gdb/testsuite/ChangeLog:
2015-02-18 Jose E. Marchesi <jose.marchesi@oracle.com>
* configure: Regenerated.
* configure.ac: Use GDB_AC_TRANSFORM.
* aclocal.m4: sinclude ../transform.m4.
This patch adds some simple tests testing the support for DTrace USDT
probes. The testsuite will be skipped as unsupported in case the user
does not have DTrace installed on her system. The tests included in the
test suite test breakpointing on DTrace probes, enabling and disabling
probes, printing of probe arguments of several types and also
breakpointing on several probes with the same name.
gdb/ChangeLog:
2015-02-17 Jose E. Marchesi <jose.marchesi@oracle.com>
* lib/dtrace.exp: New file.
* gdb.base/dtrace-probe.exp: Likewise.
* gdb.base/dtrace-probe.d: Likewise.
* gdb.base/dtrace-probe.c: Likewise.
* lib/pdtrace.in: Likewise.
* configure.ac: Output variables with the transformed names of
the strip, readelf, as and nm tools. AC_SUBST lib/pdtrace.in.
* configure: Regenerated.
This patch moves the `compute_probe_arg' and `compile_probe_arg' functions
from stap-probe.c to probe.c. The rationale is that it is reasonable to
assume that all backends will provide the `$_probe_argN' convenience
variables, and that the user must be placed on the PC of the probe when
requesting that information. The value and type of the argument can still be
determined by the probe backend via the `pops->evaluate_probe_argument' and
`pops->compile_to_ax' handlers.
Note that a test in gdb.base/stap-probe.exp had to be adjusted because the "No
SystemTap probe at PC" messages are now "No probe at PC".
gdb/ChangeLog:
2015-02-17 Jose E. Marchesi <jose.marchesi@oracle.com>
* probe.c (compute_probe_arg): Moved from stap-probe.c
(compile_probe_arg): Likewise.
(probe_funcs): Likewise.
* stap-probe.c (compute_probe_arg): Moved to probe.c.
(compile_probe_arg): Likewise.
(probe_funcs): Likewise.
gdb/testsuite/ChangeLog:
2015-02-17 Jose E. Marchesi <jose.marchesi@oracle.com>
* gdb.base/stap-probe.exp (stap_test): Remove "SystemTap" from
expected message when trying to access $_probe_* convenience
variables while not on a probe.
It definitely does not test all the RETURN_MASK_ERROR cases. But it tests at
least two of them.
gdb/testsuite/ChangeLog
2015-02-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.python/py-framefilter.exp (pagination quit - *): New tests.
On decr_pc_after_break targets, GDB adjusts the PC incorrectly if a
background single-step stops somewhere where PC-$decr_pc has a
breakpoint, and the thread that finishes the step is not the current
thread, like:
ADDR1 nop <-- breakpoint here
ADDR2 jmp PC
IOW, say thread A is stepping ADDR2's line in the background (an
infinite loop), and the user switches focus to thread B. GDB's
adjust_pc_after_break logic confuses the single-step stop of thread A
for a hit of the breakpoint at ADDR1, and thus adjusts thread A's PC
to point at ADDR1 when it should not, and reports a breakpoint hit,
when thread A did not execute the instruction at ADDR1 at all.
The test added by this patch exercises exactly that.
I can't find any reason we'd need the "thread to be examined is still
the current thread" condition in adjust_pc_after_break, at least
nowadays; it might have made sense in the past. Best just remove it,
and rely on currently_stepping().
Here's the test's log of a run with an unpatched GDB:
35 while (1);
(gdb) PASS: gdb.threads/step-bg-decr-pc-switch-thread.exp: next over nop
next&
(gdb) PASS: gdb.threads/step-bg-decr-pc-switch-thread.exp: next& over inf loop
thread 1
[Switching to thread 1 (Thread 0x7ffff7fc2740 (LWP 29027))](running)
(gdb)
PASS: gdb.threads/step-bg-decr-pc-switch-thread.exp: switch to main thread
Breakpoint 2, thread_function (arg=0x0) at ...src/gdb/testsuite/gdb.threads/step-bg-decr-pc-switch-thread.c:34
34 NOP; /* set breakpoint here */
FAIL: gdb.threads/step-bg-decr-pc-switch-thread.exp: no output while stepping
gdb/ChangeLog:
2015-02-11 Pedro Alves <pedro@codesourcery.com>
* infrun.c (adjust_pc_after_break): Don't adjust the PC just
because the event thread is not the current thread.
gdb/testsuite/ChangeLog:
2015-02-11 Pedro Alves <pedro@codesourcery.com>
* gdb.threads/step-bg-decr-pc-switch-thread.c: New file.
* gdb.threads/step-bg-decr-pc-switch-thread.exp: New file.
Some local changes I was working on related to SIGTRAP handling
resulted in "signal SIGTRAP" no longer passing the SIGTRAP to the
inferior.
Surprisingly, only annota1.exp catches this. This commit adds a test
that doesn't rely on annotations, so that at the point annotations are
finaly dropped, we still have this use case covered ...
This is a multi-threaded test to also exercise the case of first
needing to do a step-over before delivering the signal.
Tested on x86_64 Fedora 20, native, remote/extended-remote gdbserver.
gdb/testsuite/
2015-02-10 Pedro Alves <palves@redhat.com>
* gdb.threads/signal-sigtrap.c: New file.
* gdb.threads/signal-sigtrap.exp: New file.
When gdbserver is called with --multi and attach has not been called yet
and tstart is called on the gdb client, gdbserver would crash.
This patch fixes gdbserver so that it returns E01 to the gdb client.
Also this patch adds a testcase to verify this bug named no-attach-trace.exp
gdb/gdbserver/ChangeLog:
PR breakpoints/15956
* tracepoint.c (cmd_qtinit): Add check for current_thread.
gdb/testsuite/ChangeLog:
* gdb.trace/no-attach-trace.c: New file.
* gdb.trace/no-attach-trace.exp: New file.
Indicate gaps in the trace due to decode errors. Internally, a gap is
represented as a btrace function segment without instructions and with a
non-zero format-specific error code.
Show the gap when traversing the instruction or function call history.
Also indicate gaps in "info record".
It looks like this:
(gdb) info record
Active record target: record-btrace
Recording format: Branch Trace Store.
Buffer size: 64KB.
Recorded 32 instructions in 5 functions (1 gaps) for thread 1 (process 7182).
(gdb) record function-call-history /cli
1 fib inst 1,9 at src/fib.c:9,14
2 fib inst 10,20 at src/fib.c:6,14
3 [decode error (1): instruction overflow]
4 fib inst 21,28 at src/fib.c:11,14
5 fib inst 29,33 at src/fib.c:6,9
(gdb) record instruction-history 20,22
20 0x000000000040062f <fib+47>: sub $0x1,%rax
[decode error (1): instruction overflow]
21 0x0000000000400613 <fib+19>: add $0x1,%rax
22 0x0000000000400617 <fib+23>: mov %rax,0x200a3a(%rip)
(gdb)
Gaps are ignored during reverse execution and replay.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* btrace.c (ftrace_find_call): Skip gaps.
(ftrace_new_function): Initialize level.
(ftrace_new_call, ftrace_new_tailcall, ftrace_new_return)
(ftrace_new_switch): Update
level computation.
(ftrace_new_gap): New.
(ftrace_update_function): Create new function after gap.
(btrace_compute_ftrace_bts): Create gap on error.
(btrace_stitch_bts): Update parameters. Clear trace if it
becomes empty.
(btrace_stitch_trace): Update parameters. Update callers.
(btrace_clear): Reset the number of gaps.
(btrace_insn_get): Return NULL if the iterator points to a gap.
(btrace_insn_number): Return zero if the iterator points to a gap.
(btrace_insn_end): Allow gaps at the end.
(btrace_insn_next, btrace_insn_prev, btrace_insn_cmp): Handle gaps.
(btrace_find_insn_by_number): Assert that the found iterator does
not point to a gap.
(btrace_call_next, btrace_call_prev): Assert that the last function
is not a gap.
* btrace.h (btrace_bts_error): New.
(btrace_function): Update comment.
(btrace_function) <insn, insn_offset, number>: Update comment.
(btrace_function) <errcode>: New.
(btrace_thread_info) <ngaps>: New.
(btrace_thread_info) <replay>: Update comment.
(btrace_insn_get): Update comment.
* record-btrace.c (btrace_ui_out_decode_error): New.
(record_btrace_info): Print number of gaps.
(btrace_insn_history, btrace_call_history): Call
btrace_ui_out_decode_error for gaps.
(record_btrace_step_thread, record_btrace_start_replaying): Skip gaps.
testsuite/
* gdb.btrace/buffer-size.exp: Update "info record" output.
* gdb.btrace/delta.exp: Update "info record" output.
* gdb.btrace/enable.exp: Update "info record" output.
* gdb.btrace/finish.exp: Update "info record" output.
* gdb.btrace/instruction_history.exp: Update "info record" output.
* gdb.btrace/next.exp: Update "info record" output.
* gdb.btrace/nexti.exp: Update "info record" output.
* gdb.btrace/step.exp: Update "info record" output.
* gdb.btrace/stepi.exp: Update "info record" output.
* gdb.btrace/nohist.exp: Update "info record" output.
Allow the size of the branch trace ring buffer to be defined by the
user. The specified buffer size will be used when BTS tracing is
enabled for new threads.
The obtained buffer size may differ from the requested size. The
actual buffer size for the current thread is shown in the "info record"
command.
Bigger buffers mean longer traces, but also longer processing time.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* btrace.c (parse_xml_btrace_conf_bts): Add size.
(btrace_conf_bts_attributes): New.
(btrace_conf_children): Add attributes.
* common/btrace-common.h (btrace_config_bts): New.
(btrace_config)<bts>: New.
(btrace_config): Update comment.
* nat/linux-btrace.c (linux_enable_btrace, linux_enable_bts):
Use config.
* features/btrace-conf.dtd: Increment version. Add size
attribute to bts element.
* record-btrace.c (set_record_btrace_bts_cmdlist,
show_record_btrace_bts_cmdlist): New.
(record_btrace_adjust_size, record_btrace_print_bts_conf,
record_btrace_print_conf, cmd_set_record_btrace_bts,
cmd_show_record_btrace_bts): New.
(record_btrace_info): Call record_btrace_print_conf.
(_initialize_record_btrace): Add commands.
* remote.c: Add PACKET_Qbtrace_conf_bts_size enum.
(remote_protocol_features): Add Qbtrace-conf:bts:size packet.
(btrace_sync_conf): Synchronize bts size.
(_initialize_remote): Add Qbtrace-conf:bts:size packet.
* NEWS: Announce new commands and new packets.
doc/
* gdb.texinfo (Branch Trace Configuration Format): Add size.
(Process Record and Replay): Describe new set|show commands.
(General Query Packets): Describe Qbtrace-conf:bts:size packet.
testsuite/
* gdb.btrace/buffer-size: New.
gdbserver/
* linux-low.c (linux_low_btrace_conf): Print size.
* server.c (handle_btrace_conf_general_set): New.
(hanle_general_set): Call handle_btrace_conf_general_set.
(handle_query): Report Qbtrace-conf:bts:size as supported.
Add a struct to describe the branch trace configuration and use it for
enabling branch tracing.
The user will be able to set configuration fields for each tracing format
to be used for new threads.
The actual configuration that is active for a given thread will be shown
in the "info record" command.
At the moment, the configuration struct only contains a format field
that is set to the only available format.
The format is the only configuration option that can not be set via set
commands. It is given as argument to the "record btrace" command when
starting recording.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* Makefile.in (XMLFILES): Add btrace-conf.dtd.
* x86-linux-nat.c (x86_linux_enable_btrace): Update parameters.
(x86_linux_btrace_conf): New.
(x86_linux_create_target): Initialize to_btrace_conf.
* nat/linux-btrace.c (linux_enable_btrace): Update parameters.
Check format. Split into this and ...
(linux_enable_bts): ... this.
(linux_btrace_conf): New.
(perf_event_skip_record): Renamed into ...
(perf_event_skip_bts_record): ... this. Updated users.
(linux_disable_btrace): Split into this and ...
(linux_disable_bts): ... this.
(linux_read_btrace): Check format.
* nat/linux-btrace.h (linux_enable_btrace): Update parameters.
(linux_btrace_conf): New.
(btrace_target_info)<ptid>: Moved.
(btrace_target_info)<conf>: New.
(btrace_target_info): Split into this and ...
(btrace_tinfo_bts): ... this. Updated users.
* btrace.c (btrace_enable): Update parameters.
(btrace_conf, parse_xml_btrace_conf_bts, parse_xml_btrace_conf)
(btrace_conf_children, btrace_conf_attributes)
(btrace_conf_elements): New.
* btrace.h (btrace_enable): Update parameters.
(btrace_conf, parse_xml_btrace_conf): New.
* common/btrace-common.h (btrace_config): New.
* feature/btrace-conf.dtd: New.
* record-btrace.c (record_btrace_conf): New.
(record_btrace_cmdlist): New.
(record_btrace_enable_warn, record_btrace_open): Pass
&record_btrace_conf.
(record_btrace_info): Print recording format.
(cmd_record_btrace_bts_start): New.
(cmd_record_btrace_start): Call cmd_record_btrace_bts_start.
(_initialize_record_btrace): Add "record btrace bts" subcommand.
Add "record bts" alias command.
* remote.c (remote_state)<btrace_config>: New.
(remote_btrace_reset, PACKET_qXfer_btrace_conf): New.
(remote_protocol_features): Add qXfer:btrace-conf:read.
(remote_open_1): Call remote_btrace_reset.
(remote_xfer_partial): Handle TARGET_OBJECT_BTRACE_CONF.
(btrace_target_info)<conf>: New.
(btrace_sync_conf, btrace_read_config): New.
(remote_enable_btrace): Update parameters. Call btrace_sync_conf and
btrace_read_conf.
(remote_btrace_conf): New.
(init_remote_ops): Initialize to_btrace_conf.
(_initialize_remote): Add qXfer:btrace-conf packet.
* target.c (target_enable_btrace): Update parameters.
(target_btrace_conf): New.
* target.h (target_enable_btrace): Update parameters.
(target_btrace_conf): New.
(target_object)<TARGET_OBJECT_BTRACE_CONF>: New.
(target_ops)<to_enable_btrace>: Update parameters and comment.
(target_ops)<to_btrace_conf>: New.
* target-delegates: Regenerate.
* target-debug.h (target_debug_print_const_struct_btrace_config_p)
(target_debug_print_const_struct_btrace_target_info_p): New.
NEWS: Announce new command and new packet.
doc/
* gdb.texinfo (Process Record and Replay): Describe the "record
btrace bts" command.
(General Query Packets): Describe qXfer:btrace-conf:read packet.
(Branch Trace Configuration Format): New.
gdbserver/
* linux-low.c (linux_low_enable_btrace): Update parameters.
(linux_low_btrace_conf): New.
(linux_target_ops)<to_btrace_conf>: Initialize.
* server.c (current_btrace_conf): New.
(handle_btrace_enable): Rename to ...
(handle_btrace_enable_bts): ... this. Pass ¤t_btrace_conf
to target_enable_btrace. Update comment. Update users.
(handle_qxfer_btrace_conf): New.
(qxfer_packets): Add btrace-conf entry.
(handle_query): Report qXfer:btrace-conf:read as supported packet.
* target.h (target_ops)<enable_btrace>: Update parameters and comment.
(target_ops)<read_btrace_conf>: New.
(target_enable_btrace): Update parameters.
(target_read_btrace_conf): New.
testsuite/
* gdb.btrace/delta.exp: Update "info record" output.
* gdb.btrace/enable.exp: Update "info record" output.
* gdb.btrace/finish.exp: Update "info record" output.
* gdb.btrace/instruction_history.exp: Update "info record" output.
* gdb.btrace/next.exp: Update "info record" output.
* gdb.btrace/nexti.exp: Update "info record" output.
* gdb.btrace/step.exp: Update "info record" output.
* gdb.btrace/stepi.exp: Update "info record" output.
* gdb.btrace/nohist.exp: Update "info record" output.
Typing "enable count" by itself crashes GDB. Also, if you omit the
breakpoint number/range, the error message is not very clear:
(gdb) enable count 2
warning: bad breakpoint number at or near ''
(gdb) enable count
Segmentation fault (core dumped)
With this patch, the error messages are slightly more helpful:
(gdb) enable count 2
Argument required (one or more breakpoint numbers).
(gdb) enable count
Argument required (hit count).
gdb/ChangeLog:
PR gdb/15678
* breakpoint.c (map_breakpoint_numbers): Check for empty args
string.
(enable_count_command): Check args for NULL value.
gdb/testsuite/ChangeLog:
PR gdb/15678
* gdb.base/ena-dis-br.exp: Test "enable count" for bad user input.
The buildbot shows that this test is still racy, and occasionally
fails with time outs on some machines. I'd like to get major issues
with load out of the way.
The test currently exits after 180s, which is just a random number,
that has no relation to what the .exp file considers a time out. This
commit makes the program wait a bit longer than what the .exp file
considers a time out, and, resets the timer for each iteration.
Tested on x86_64 Fedora 20, native and extended-remote gdbserver.
gdb/testsuite/
2015-02-06 Pedro Alves <palves@redhat.com>
* gdb.threads/attach-many-short-lived-threads.c (SECONDS): New
macro.
(seconds_left, again): New globals.
(main): Wait seconds_left in a 1-second sleep loop instead of
sleeping 180 seconds. If 'again' is set, reset the seconds
counter.
* gdb.threads/attach-many-short-lived-threads.exp (test): Set
'again' in the inferior before detaching. Print the seconds left.
(options): New global.
(top level): Build program with -DTIMEOUT=$timeout.
The buildbot shows that some machines FAIL this test frequently.
E.g.: https://sourceware.org/ml/gdb-testers/2015-q1/msg00997.html
If I stress my machine, I can sometimes see it fail too.
Bumping the 200 limit and tweaking the test to show the step count, I
get:
...
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 12 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 8 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 13 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 7 times
--> FAIL: gdb.base/gdb-sigterm.exp: SIGTERM stepped 228 times <--
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 11 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 13 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 12 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 8 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 9 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 7 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 11 times
PASS: gdb.base/gdb-sigterm.exp: SIGTERM stepped 8 times
...
Thinking that this might be a problem of SIGTERM reaching GDB, but
then the event loop taking too long to handle it, I hacked GDB to
print a debug log whenever the SIGTERM handler was called, and,
whenever the event loop finally calls the async SIGTERM handler.
Here's what I see:
infrun: 30011 [Thread 30011],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x4005de
--> infrun: got SIGTERM <--
infrun: stepping inside range [0x4005de-0x4005e0]
infrun: resume (step=1, signal=GDB_SIGNAL_0), ...
infrun: prepare_to_wait
--> infrun: handling async SIGTERM <--
Cannot execute this command while the target is running.
Use the "interrupt" command to stop the target
and then try again.
gdb.base/gdb-sigterm.exp: expect eof #27
FAIL: gdb.base/gdb-sigterm.exp: SIGTERM stepped 228 times
So, no delay on the GDB side. It just happens that occasionally it
takes more than 200 single-steps before SIGTERM even reaches GDB.
This just looks like a kernel/scheduling issue --- some extra usage
spike in the system (e.g., an I/O spike) might cause it for me. For
the build slaves, I'm guessing they're frequently busy enough to trip
on this often. Particularly more so now that we're having them run
tests in parallel mode.
The fix is to detect failure by timeout instead of counting single
steps. This should be more reliable. Indeed for me, after this
commit, I couldn't trigger a FAIL anymore, even after letting the test
run for an hour.
By timeout is also nicer in that a board file for a slow host/target
can increase it (like, e.g., an embedded GNU/Linux board).
Tested on x86_64 Fedora 20, native, gdbserver, and extended-remote
gdbserver.
gdb/testsuite/
2015-02-06 Pedro Alves <palves@redhat.com>
* gdb.base/gdb-sigterm.c (main): Use the TIMEOUT define to
determine how many seconds to pass to 'alarm'.
* gdb.base/gdb-sigterm.exp (top level): Build program with
-DTIMEOUT=$timeout.
(do_test): Return success/failure indication. Add more verbose
logging. Don't fail if 200 single steps are seen. Instead, fail
when the test times out.
(passes): New global.
(top level): Break the testing loop if testing fails on any
iteration. Use gdb_assert.
This commit modifies the test program gdb.base/info-os.c so that
it cleans up all allocated System V IPC objects when a fatal
error occurs. Without this, it was possible for the program
to leave IPC objects on the system, and such objects persist
until they are manually deleted or the system reboots.
I looked at changing the SysV IPC key for allocating the IPC objects to
IPC_PRIVATE. That would prevent errors due to namespace conflicts with the
key. However, the test needs to read the actual key number from the 'info
os' command output, and IPC_PRIVATE won't work for that.
gdb/testsuite/ChangeLog:
2015-02-04 Don Breazeal <donb@codesourcery.com>
* gdb.base/info-os.c (shmid, semid, msqid): Make variables static
and initialize them.
(ipc_cleanup): New function.
(main): Don't declare shmid, semid, and msqid. Add a call to
atexit so that we call ipc_cleanup on exit.
Running the testsuite with the native-extended-gdbserver.exp board and
passing a variant spec, like
make check RUNTESTFLAGS="--target_board=native-extended-gdbserver/-m32"
results in dejagnu trying to open a rsh connection to
"native-extended-gdbserver", which of course is wrong. The point of
this board is running things locally.
The issue is that the native-extended-gdbserver board does not clear
the "isremote" flag properly.
Reported by Sergio at:
https://sourceware.org/ml/gdb-patches/2015-02/msg00067.html
testsuite/
2015-02-04 Pedro Alves <palves@redhat.com>
* boards/native-extended-gdbserver.exp: Remove any target variant
specifications from the board name before clearing the isremote
flag from board_info.
Every type has to pay the price in memory usage for their presence.
The proper place for them is in the type_specific field which exists
for this purpose.
gdb/ChangeLog:
* dwarf2read.c (process_structure_scope): Update setting of
TYPE_VPTR_BASETYPE, TYPE_VPTR_FIELDNO.
* gdbtypes.c (internal_type_vptr_fieldno): New function.
(set_type_vptr_fieldno): New function.
(internal_type_vptr_basetype): New function.
(set_type_vptr_basetype): New function.
(get_vptr_fieldno): Update setting of TYPE_VPTR_FIELDNO,
TYPE_VPTR_BASETYPE.
(allocate_cplus_struct_type): Initialize vptr_fieldno.
(recursive_dump_type): Printing of vptr_fieldno, vptr_basetype ...
(print_cplus_stuff): ... moved here.
(copy_type_recursive): Don't copy TYPE_VPTR_BASETYPE.
* gdbtypes.h (struct main_type): Members vptr_fieldno, vptr_basetype
moved to ...
(struct cplus_struct_type): ... here. All uses updated.
(TYPE_VPTR_FIELDNO, TYPE_VPTR_BASETYPE): Rewrite.
(internal_type_vptr_fieldno, set_type_vptr_fieldno): Declare.
(internal_type_vptr_basetype, set_type_vptr_basetype): Declare.
* stabsread.c (read_tilde_fields): Update setting of
TYPE_VPTR_FIELDNO, TYPE_VPTR_BASETYPE.
gdb/testsuite/ChangeLog:
* gdb.base/maint.exp <maint print type argc>: Update expected output.
Consider the following declarations:
type Array_Type is array (Integer range <>) of Integer;
type Record_Type (N : Integer) is record
A : Array_Type (1 .. N);
end record;
R : Record_Type := Get (10);
It defines what Ada programers call a "discriminated record", where
"N" is a component of that record called a "discriminant", and where
"A" is a component defined as an array type whose upper bound is
equal to the value of the discriminant.
So far, we rely on a number of fairly complex GNAT-specific encodings
to handle this situation. This patch is to enhance GDB to be able to
print this record in the case where the compiler has been modified
to replace those encodings by pure DWARF constructs.
In particular, the debugging information generated for the record above
looks like the following. "R" is a record..
.uleb128 0x10 # (DIE (0x13e) DW_TAG_structure_type)
.long .LASF17 # DW_AT_name: "foo__record_type"
... whose is is of course dynamic (not our concern here)...
.uleb128 0xd # DW_AT_byte_size
.byte 0x97 # DW_OP_push_object_address
.byte 0x94 # DW_OP_deref_size
.byte 0x4
.byte 0x99 # DW_OP_call4
.long 0x19b
.byte 0x23 # DW_OP_plus_uconst
.uleb128 0x7
.byte 0x9 # DW_OP_const1s
.byte 0xfc
.byte 0x1a # DW_OP_and
.byte 0x1 # DW_AT_decl_file (foo.adb)
.byte 0x6 # DW_AT_decl_line
... and then has 2 members, fist "n" (our discriminant);
.uleb128 0x11 # (DIE (0x153) DW_TAG_member)
.ascii "n\0" # DW_AT_name
.byte 0x1 # DW_AT_decl_file (foo.adb)
.byte 0x6 # DW_AT_decl_line
.long 0x194 # DW_AT_type
.byte 0 # DW_AT_data_member_location
... and "A"...
.uleb128 0x11 # (DIE (0x181) DW_TAG_member)
.ascii "a\0" # DW_AT_name
.long 0x15d # DW_AT_type
.byte 0x4 # DW_AT_data_member_location
... which is an array ...
.uleb128 0x12 # (DIE (0x15d) DW_TAG_array_type)
.long .LASF18 # DW_AT_name: "foo__record_type__T4b"
.long 0x194 # DW_AT_type
... whose lower bound is implicitly 1, and the upper bound
a reference to DIE 0x153 = "N":
.uleb128 0x13 # (DIE (0x16a) DW_TAG_subrange_type)
.long 0x174 # DW_AT_type
.long 0x153 # DW_AT_upper_bound
This patch enhanced GDB to understand references to other DIEs
where the DIE's address is at an offset of its enclosing type.
The difficulty was that the address used to resolve the array's
type (R's address + 4 bytes) is different from the address used
as the base to compute N's address (an offset to R's address).
We're solving this issue by using a stack of addresses rather
than a single address when trying to resolve a type. Each address
in the stack corresponds to each containing level. For instance,
if resolving the field of a struct, the stack should contain
the address of the field at the top, and then the address of
the struct. That way, if the field makes a reference to an object
of the struct, we can retrieve the address of that struct, and
properly resolve the dynamic property references that struct.
gdb/ChangeLog:
* gdbtypes.h (struct dynamic_prop): New PROP_ADDR_OFFSET enum
kind.
* gdbtypes.c (resolve_dynamic_type_internal): Replace "addr"
parameter by "addr_stack" parameter.
(resolve_dynamic_range): Replace "addr" parameter by
"stack_addr" parameter. Update function documentation.
Update code accordingly.
(resolve_dynamic_array, resolve_dynamic_union)
(resolve_dynamic_struct, resolve_dynamic_type_internal): Likewise.
(resolve_dynamic_type): Update code, following the changes made
to resolve_dynamic_type_internal's interface.
* dwarf2loc.h (struct property_addr_info): New.
(dwarf2_evaluate_property): Replace "address" parameter
by "addr_stack" parameter. Adjust function documentation.
(struct dwarf2_offset_baton): New.
(struct dwarf2_property_baton): Update documentation of
field "referenced_type" to be more general. New field
"offset_info" in union data field.
* dwarf2loc.c (dwarf2_evaluate_property): Replace "address"
parameter by "addr_stack" parameter. Adjust code accordingly.
Add support for PROP_ADDR_OFFSET properties.
* dwarf2read.c (attr_to_dynamic_prop): Add support for
DW_AT_data_member_location attributes as well. Use case
statements instead of if/else condition.
gdb/testsuite/ChangeLog:
* gdb.ada/disc_arr_bound: New testcase.
Tested on x86_64-linux, no regression.
This is preparation work to avoid a regression in the Ada/varobj.
An upcoming patch is going to add support for types in DWARF
which have dynamic properties whose value is a reference to another
DIE.
Consider for instance the following declaration:
type Variant_Type (N : Int := 0) is record
F : String(1 .. N) := (others => 'x');
end record;
type Variant_Type_Access is access all Variant_Type;
VTA : Variant_Type_Access := null;
This declares a variable "VTA" which is an access (=pointer)
to a variant record Variant_Type. This record contains two
components, the first being "N" (the discriminant), and the
second being "F", an array whose lower bound is 1, and whose
upper bound depends on the value of "N" (the discriminant).
Of interest to us, here, is that second component ("F"), and
in particular its bounds. The debugging info, and in particular
the info for the array looks like the following...
.uleb128 0x9 # (DIE (0x91) DW_TAG_array_type)
.long .LASF16 # DW_AT_name: "bar__variant_type__T2b"
.long 0xac # DW_AT_GNAT_descriptive_type
.long 0x2cb # DW_AT_type
.long 0xac # DW_AT_sibling
.uleb128 0xa # (DIE (0xa2) DW_TAG_subrange_type)
.long 0xc4 # DW_AT_type
.long 0x87 # DW_AT_upper_bound
.byte 0 # end of children of DIE 0x91
... where the upper bound of the array's subrange type is a reference
to "n"'s DIE (0x87):
.uleb128 0x8 # (DIE (0x87) DW_TAG_member)
.ascii "n\0" # DW_AT_name
[...]
Once the patch to handle this dynamic property gets applied,
this is what happens when creating a varobj for variable "VTA"
(whose value is null), and then trying to list its children:
(gdb)
-var-create vta * vta
^done,name="vta",numchild="2",value="0x0",
type="bar.variant_type_access",has_more="0"
(gdb)
-var-list-children 1 vta
^done,numchild="2",
children=[child={name="vta.n",[...]},
child={name="vta.f",exp="f",
numchild="43877616", <<<<-----
value="[43877616]", <<<<-----
type="array (1 .. n) of character"}],
has_more="0"
It has an odd number of children.
In this case, we cannot really determine the number of children,
since that number depends on the value of a field in a record
for which we do not have a value. Up to now, the value we've been
displaying is zero - meaning we have an empty array.
What happens in this case, is that, because the VTA is a null pointer,
we're not able to resolve the pointer's target type, and therefore
end up asking ada_varobj_get_array_number_of_children to return
the number of elements in that array; for that, it relies blindly
on get_array_bounds, which assumes the type is no longer dynamic,
and therefore the reads the bound without seeing that it's value
is actually a reference rather than a resolved constant.
This patch prevents the issue by explicitly handling the case of
dynamic arrays, and returning zero child in that case.
gdb/ChangeLog:
* ada-varobj.c (ada_varobj_get_array_number_of_children):
Return zero if PARENT_VALUE is NULL and parent_type's
range type is dynamic.
gdb/testsuite/ChangeLog:
* gdb.ada/mi_var_array: New testcase.
Tested on x86_64-linux.
gdb/ChangeLog:
* NEWS: Mention gdb.Objfile.username.
* python/py-objfile.c (objfpy_get_username): New function.
(objfile_getset): Add "username".
gdb/doc/ChangeLog:
* python.texi (Objfiles In Python): Document Objfile.username.
gdb/testsuite/ChangeLog:
* gdb.python/py-objfile.exp: Add tests for objfile.username.
Add test for objfile.filename, objfile.username after objfile
has been unloaded.
This further improves this testcase to check the output of
our calls to gdb.lookup_type.
gdb/ChangeLog:
* gdb.python/py-lookup-type.exp (test_lookup_type): Change
the second test to print the name attribute of value
returned by the call to gdb.lookup_type, and adjust
the expected output accordingly.
GCC5 defaults to the GNU11 standard for C and warns by default for
implicit function declarations and implicit return types.
https://gcc.gnu.org/gcc-5/porting_to.html
Fixing these issues in the testsuite turns 9 untested and 17 unsupported
testcases into 417 new passes when compiling with GCC5.
gdb/testsuite/ChangeLog:
* gdb.arch/i386-bp_permanent.c (standard): New declaration.
* gdb.base/disp-step-fork.c: Include unistd.h.
* gdb.base/siginfo-obj.c: Include stdio.h.
* gdb.base/siginfo-thread.c: Likewise.
* gdb.mi/non-stop.c: Include unistd.h.
* gdb.mi/nsthrexec.c: Include stdio.h.
* gdb.mi/pthreads.c: Include unistd.h.
* gdb.modula2/unbounded1.c (main): Declare returns int.
* gdb.reverse/consecutive-reverse.c: Likewise.
* gdb.threads/create-fail.c: Include unistd.h.
* gdb.threads/killed.c: Likewise.
* gdb.threads/linux-dp.c: Likewise.
* gdb.threads/non-ldr-exc-1.c: Include stdio.h and string.h.
* gdb.threads/non-ldr-exc-2.c: Likewise.
* gdb.threads/non-ldr-exc-3.c: Likewise.
* gdb.threads/non-ldr-exc-4.c: Likewise.
* gdb.threads/pthreads.c: Include unistd.h.
(main): Declare returns int.
* gdb.threads/tls-main.c (foo): New declaration.
* gdb.threads/watchpoint-fork-mt.c: Define _GNU_SOURCE.
In the situation described in bug 17416 [1]:
* "set print object" is on;
* The variable object is a pointer to a struct, and it contains an
invalid value (e.g. NULL, or random uninitialized value);
* The variable object (struct) has a child which is also a pointer to a
struct;
* We try to use "-var-list-children".
... an exception thrown in value_ind can propagate too far and leave an
half-built variable object, leading to a wrong state. This patch adds a
TRY_CATCH to catch it and makes value_rtti_indirect_type return NULL in
that case, meaning that the type of the pointed object could not be
found.
A test for the fix is also added.
New in v2:
* Added test.
* Restructured "catch" code.
* Added details about the bug in commit log.
gdb/Changelog:
* valops.c (value_rtti_indirect_type): Catch exception thrown by
value_ind.
gdb/testsuite/ChangeLog
* gdb.mi/mi-var-list-children-invalid-grandchild.c: New file.
* gdb.mi/mi-var-list-children-invalid-grandchild.exp: New file.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=17416
Add a flag field is_noreturn to struct func_type. Make calling_convention
a small bit field to not increase the size of the struct. Set is_noreturn
if the new GCC5/DWARF5 DW_AT_noreturn is set on a DW_TAG_subprogram.
Use this information to warn the user before doing a finish or return from
a function that does not return normally to its caller.
(gdb) finish
warning: Function endless does not return normally.
Try to finish anyway? (y or n)
(gdb) return
warning: Function does not return normally to caller.
Make endless return now? (y or n)
gdb/ChangeLog
* dwarf2read.c (read_subroutine_type): Set TYPE_NO_RETURN from
DW_AT_noreturn.
* gdbtypes.h (struct func_type): Add is_noreturn field flag. Make
calling_convention an 8 bit bit field.
(TYPE_NO_RETURN): New macro.
* infcmd.c (finish_command): Query if function does not return
normally.
* stack.c (return_command): Likewise.
gdb/testsuite/ChangeLog
* gdb.base/noreturn-return.c: New file.
* gdb.base/noreturn-return.exp: New file.
* gdb.base/noreturn-finish.c: New file.
* gdb.base/noreturn-finish.exp: New file.
include/ChangeLog
* dwarf2.def (DW_AT_noreturn): New DWARF5 attribute.
The dwarf2.h addition and the code to emit the new attribute is already in
the gcc tree.
linux_nat_is_async_p currently always returns true, even when the
target is _not_ async. That confuses
gdb_readline_wrapper/gdb_readline_wrapper_cleanup, which
force-disables target-async while the secondary prompt is active. As
a result, when gdb_readline_wrapper returns, the target is left async,
even through it was sync to begin with.
That can result in weird bugs, like the one the test added by this
commit exposes.
Ref: https://sourceware.org/ml/gdb-patches/2015-01/msg00592.html
gdb/ChangeLog:
2015-01-23 Pedro Alves <palves@redhat.com>
* linux-nat.c (linux_is_async_p): New macro.
(linux_nat_is_async_p):
(linux_nat_terminal_inferior): Check whether the target can async
instead of whether it is already async.
(linux_nat_terminal_ours): Don't check whether the target is
async.
(linux_async_pipe): Use linux_is_async_p.
gdb/testsuite/ChangeLog:
2015-01-23 Pedro Alves <palves@redhat.com>
* gdb.threads/continue-pending-after-query.c: New file.
* gdb.threads/continue-pending-after-query.exp: New file.
gdb_interact is a small utility that we have found quite useful to debug
test cases.
Putting gdb_interact in a test suspends it and allows to interact with
gdb to inspect whatever you want. You can then type ">>>" to resume the
test execution. Of course, this is only for gdb devs. It wouldn't make
sense to leave a gdb_interact permanently in a test case.
When starting the interaction with the user, the script prints this
banner:
+------------------------------------------+
| Script interrupted, you can now interact |
| with by gdb. Type >>> to continue. |
+------------------------------------------+
Notes:
* When gdb is launched, the gdb_spawn_id variable (lib/gdb.exp) is
assigned -1. Given the name, I would expect it to contain the gdb
expect spawn id, which is needed for interact. I changed all places
that set gdb_spawn_id to -1 to set it to the actual gdb spawn id
instead.
* When entering the "interact" mode, the last (gdb) prompt is already
eaten by expect, so it doesn't show up on the terminal. Subsequent
prompts do appear though. We tried to print "(gdb)" just before the
interact to replace it. However, it could be misleading if you are
debugging an MI test case, it makes you think that you are typing in a
CLI prompt, when in reality it's MI. In the end I decided that since
the feature is for developers who know what they're doing and that one
is normally consciously using gdb_interact, the script doesn't need
to babysit the user.
* There are probably some quirks depending on where in the script
gdb_interact appears (e.g. it could interfere with following
commands and make them fail), but it works for most cases. Quirks can
always be fixed later.
The idea and original implementation was contributed by Anders
Granlund, a colleague of mine. Thanks to him.
gdb/testsuite/ChangeLog:
* gdb.base/statistics.exp: Assign spawn id to gdb_spawn_id.
* gdb.base/valgrind-db-attach.exp: Same.
* gdb.base/valgrind-infcall.exp: Same.
* lib/mi-support.exp (default_mi_gdb_start): Same.
* lib/prompt.exp (default_prompt_gdb_start): Same.
* lib/gdb.exp (default_gdb_spawn): Same.
(gdb_interact): New.
TBH while I always comment reasons for each of the compilation options in
reality I tried them all and chose that combination that needs the most simple
compile/compile-object-load.c (ld.so emulation) implementation.
gdb/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile.c (_initialize_compile): Use -fPIE for compile_args.
gdb/testsuite/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.compile/compile.exp (pointer to jit function): New test.
This patch updates two attach tests to use utility procs for checking if
the attach test should run and for launching the program to be attached, as
follows:
1) Use can_spawn_for_attach instead of is_remote target
2) Use spawn_wait_for_attach instead of exec/sleep
Tested (1) with i686-mingw32 host and i686-pc-linux-gnu build/target and
both with x86_64 Ubuntu.
gdb/testsuite/ChangeLog:
* gdb.base/attach-pie-noexec.exp: Use can_spawn_for_attach
instead of checking whether the target board is remote and
use spawn_wait_for_attach instead of exec/sleep.
* gdb.base/attach-twice.exp: Likewise.
Consider the following code:
type Table is array (Positive range <>) of Integer;
type Object (N : Integer) is record
Data : Table (1 .. N);
end record;
My_Object : Object := (N => 3, Data => (3, 5, 8));
Trying to print the range and length of the My_Object.Data array yields:
(gdb) print my_object.data'first
$1 = 1
(gdb) print my_object.data'last
$2 = 0
(gdb) print my_object.data'length
$3 = 0
The first one is correct, and that is thanks to the fact that
the lower bound is statically known. However, for the upper
bound, and consequently the array's length, the values are incorrect.
It should be:
(gdb) print my_object.data'last
$2 = 3
(gdb) print my_object.data'length
$3 = 3
What happens here is that ada_array_bound_from_type sees that
our array has a parallel "___XA" type, and therefore tries to
use it. In particular, it described our array's index type as:
[...]___XDLU_1__n, which means lower bound = 1, and upper bound
is value of "n". Unfortunately, ada_array_bound_from_type does
not have access to the discriminant, and is therefore unable to
compute the bound correctly.
Fortunately, at this stage, the bound has already been computed
a while ago, and therefore doesn't need to be re-computed here.
This patch fixes the issue by ignoring that ___XA type if the array
is marked as already fixed.
This also fixes the same issue with packed arrays.
gdb/ChangeLog:
* ada-lang.c (ada_array_bound_from_type): Ignore array's parallel
___XA type if the array has already been fixed.
gdb/testsuite/ChangeLog:
* gdb.ada/var_arr_attrs: New testcase.
Executing a gdb script that runs the inferior (from the command line
with -x), and has it hit breakpoints with breakpoint commands that
themselves run the target, is currently broken on async targets
(Linux, remote).
While we're executing a command list or a script, we force the
interpreter to be sync, which results in some functions nesting an
event loop and waiting for the target to stop, instead of returning
immediately and having the top level event loop handle the stop.
The issue with this bug is simply that bpstat_do_actions misses
checking whether the interpreter is sync. When we get here, in the
case of executing a script (or, when the interpreter is sync), the
program has already advanced to the next breakpoint, through
maybe_wait_sync_command_done. We need to process its breakpoints
immediately, just like with a sync target.
Tested on x86_64 Fedora 20.
gdb/
2015-01-14 Pedro Alves <palves@redhat.com>
PR gdb/17525
* breakpoint.c: Include "interps.h".
(bpstat_do_actions_1): Also check whether the interpreter is
async.
gdb/testsuite/
2015-01-14 Pedro Alves <palves@redhat.com>
Joel Brobecker <brobecker@adacore.com>
PR gdb/17525
* gdb.base/bp-cmds-execution-x-script.c: New file.
* gdb.base/bp-cmds-execution-x-script.exp: New file.
* gdb.base/bp-cmds-execution-x-script.gdb: New file.
Commit d3d4baed (PR python/17372 - Python hangs when displaying
help()) had the side effect of causing 'gdb -batch' to leave the
terminal in the wrong state if the program was run. E.g,.
$ echo 'main(){*(int*)0=0;}' | gcc -x c -; ./gdb/gdb -batch -ex r ./a.out
Program received signal SIGSEGV, Segmentation fault.
0x00000000004004ff in main ()
$
If you start typing the next command, seemingly nothing happens - GDB
left the terminal with echo disabled.
The issue is that that "r" ends up in fetch_inferior_event, which
calls reinstall_readline_callback_handler_cleanup, which causes
readline to prep the terminal (raw, echo disabled). But "-batch"
causes GDB to exit before the top level event loop is first started,
and then nothing de-preps the terminal.
The reinstall_readline_callback_handler_cleanup function's intro
comment mentions:
"Need to do this as we go back to the event loop, ready to process
further input."
but the implementation forgets the case of when the interpreter is
sync, which indicates we won't return to the event loop yet, or as in
the case of -batch, we have not started it yet.
The fix is to not install the readline callback in that case.
For the test, in this case, checking that command echo still works is
sufficient. Comparing stty output before/after running GDB is even
better. Because stty may not be available, the test tries both ways.
In any case, since expect's spawn (what we use to start gdb) creates a
new pseudo tty, another expect spawn or tcl exec after GDB exits would
not see the wrong terminal settings. So instead, the test spawns a
shell and runs stty and GDB in it.
Tested on x86_64 Fedora 20.
gdb/
2015-01-14 Pedro Alves <palves@redhat.com>
PR cli/17828
* infrun.c (reinstall_readline_callback_handler_cleanup): Don't
reinstall if the interpreter is sync.
gdb/testsuite/
2015-01-14 Pedro Alves <palves@redhat.com>
PR cli/17828
* gdb.base/batch-preserve-term-settings.c: New file.
* gdb.base/batch-preserve-term-settings.exp: New file.
gdb/Changelog:
* objfiles.c (objfile_filename): New function.
* objfiles.h (objfile_filename): Declare it.
(objfile_name): Add function comment.
* python/py-objfile.c (objfpy_lookup_objfile_by_name): Try both the
bfd file name (which may be realpath'd), and the original name.
gdb/testsuite/ChangeLog:
* gdb.python/py-objfile.exp: Test gdb.lookup_objfile on symlinked
binary.
A sanity-check in my release scripts caught something: After having
created the tarballs, I verify that no checked-in file disappeared
in the process, and lo and behod, it found that the following file
got wiped:
- gdb/testsuite/dg-extract-results.py:
And it's not part of the tarball either.
I don't understand while we delete all *.py files in gdb/testsuite,
since I don't see a rule that expected to create one. A run of the
testsuite also doesn't seem to be creating .py files there.
I traced this to the following commit, which unfortunately provided
no explanation. Perhaps we used to run some tests in the gdb/testsuite
directory and caused files to be left behind there. Perhaps we still
do today?
In the meantime, Executive Decision: In order to allow me to create
tarballs without losing files, I removed it. It's easy to put something
back if we find out why it might still be needed.
gdb/testsuite/ChangeLog:
* Makefile.in (clean mostlyclean): Do not delete *.py.
Tested on x86_64-linux by running the src-release.sh script again,
and this time, dg-extract-results.py no longer gets wiped.
The following change...
commit 1994afbf19
Date: Tue Dec 23 07:55:39 2014 -0800
Subject: Look up primitive types as symbols.
... caused the following regression:
% gdb
(gdb) set lang ada
(gdb) python print gdb.lookup_type('character')
Traceback (most recent call last):
File "<string>", line 1, in <module>
gdb.error: No type named character.
Error while executing Python code.
This is because the language_lookup_primitive_type_as_symbol call
was moved to the la_lookup_symbol_nonlocal hook. A couple of
implementations have been upated accordingly, but the Ada version
has not. This patch fixes this omission.
gdb/ChangeLog:
* ada-lang.c (ada_lookup_symbol_nonlocal): If name not found
in static block, then try searching for primitive types.
gdb/testsuite/ChangeLog:
* gdb.python/py-lookup-type.exp: New file.
The previous change to py-prompt.exp made it return without restoring
GDBFLAGS, resulting in breaking the following tests:
$ make check RUNTESTFLAGS="--target_board=native-gdbserver --directory=gdb.python"
...
Running src/gdb/testsuite/gdb.python/py-prompt.exp ...
Running src/gdb/testsuite/gdb.python/py-section-script.exp ...
ERROR: (timeout) GDB never initialized after 10 seconds.
ERROR: no fileid for gdbuild
ERROR: Couldn't send python print ('test') to GDB.
ERROR: no fileid for gdbuild
ERROR: Couldn't send python print (sys.version_info[0]) to GDB.
ERROR: no fileid for gdbuild
ERROR: Couldn't send python print (sys.version_info[1]) to GDB.
ERROR: no fileid for gdbuild
ERROR: no fileid for gdbuild
...
gdb/testsuite/
2015-01-12 Pedro Alves <palves@redhat.com>
* gdb.python/py-prompt.exp: When the board can't spawn for attach,
restore GDBFLAGS before returning.
for x86_64 -m32 run one gets:
+FAIL: gdb.python/py-frame.exp: test Frame.read_register(rip)
I do not have x32 OS here but the %rip test should PASS there I think.
On Sun, 11 Jan 2015 14:58:06 +0100, Yao Qi wrote:
With your patch applied, this test is skipped on 'x86_64 -m32'. I
prefer to increasing the test coverage, so how about extending the test
for 'x86_64 -m32'? I mean test Frame.read_register(eip)...
gdb/testsuite/ChangeLog
2015-01-12 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.python/py-frame.exp (test Frame.read_register(rip)): Use
is_amd64_regs_target and is_x86_like_target.
gdb/testsuite/ChangeLog:
* lib/dwarf.exp (Dwarf): Flag an error if a numeric attribute value
is given without an explicit form.
* gdb.dwarf2/arr-subrange.exp: Specify forms for all numeric
attributes.
* gdb.dwarf/corrupt.exp: Ditto.
* gdb.dwarf2/enum-type.exp: Ditto.
* gdb.trace/entry-values.exp: Ditto.
* gdb.trace/unavailable-dwarf-piece.exp: Ditto.
gdb/ChangeLog:
PR gdb/15830
* NEWS: The "maint demangle" command is renamed as "demangle".
* demangle.c: #include cli/cli-utils.h, language.h.
(demangle_command): New function.
(_initialize_demangle): Add new command "demangle".
* maint.c (maintenance_demangle): Stub out.
(_initialize_maint_cmds): Update help text for "maint demangle",
and mark as deprecated.
gdb/doc/ChangeLog:
* gdb.texinfo (Debugging C Plus Plus): Mention "demangle".
(Symbols): Ditto.
(Maintenance Commands): Delete docs for "maint demangle".
gdb/testsuite/ChangeLog:
* gdb.base/maint.exp: Remove references to "maint demangle".
* gdb.cp/demangle.exp: Update. "maint demangle" -> "demangle".
Add tests for explicitly specifying language to demangle.
* gdb.dlang/demangle.exp: Ditto.
This commit adds a non-stop mode test originally inspired by
signal-while-stepping-over-bp-other-thread.exp, that exposes the
thread starvation issues fixed by the previous patches. It sets a set
of threads stepping in parallel, and has one of them get a signal.
Without the previous fixes, this would fail with timeouts.
gdb/testsuite/
2015-01-09 Pedro Alves <palves@redhat.com>
* gdb.threads/non-stop-fair-events.c: New file.
* gdb.threads/non-stop-fair-events.exp: New file.
This patch fixes the watch_thread_num.exp test to work when the target
is better at making event handling be fair among threads.
I wrote patches that make GDB native and GDBserver event handling
fairer between threads. That is, if threads A and B both
simultaneously trigger some debug event, GDB will pick either A or B
at random, rather than always handling the event of A first. There's
code for that in the Linux backends (gdb and gdbserver) already, but
it can be improved, and only works in all-stop mode.
With those fixes in place, I found that the watch_thread_num.exp would
often time out. The problem is that the test only works _because_
event handling isn't as fair as intended. With the fairness fixes,
the test falls victim of PR10116 (gdb drops watchpoints on
multi-threaded apps) quite often.
To expand on the PR10116 reference, consider that stop events are
serialized to GDB core, through target_wait. Say a thread-specific
watchpoint as set on thread A. When the "right" thread and some other
"wrong" thread both trigger a watchpoint simultaneously, the target
may report the "wrong" thread's hit to GDB first (thread B). When
handling that event, GDB notices the watchpoint is for another thread,
and so shouldn't cause a user-visible stop. On resume, GDB saves the
now current value of the watched expression. Afterwards, the "right"
thread (thread A) reports its watchpoint trigger. But the watched
value hasn't changed since GDB last saved it, and so GDB doesn't
report the watchpoint hit to the user.
The way the test is written, the watchpoint is associated with the
first thread that happens to report an event. It happens that GDB is
processing events much more often for one of the threads, which
usually will be that same first thread.
Hacking the test with "set debug infrun 1", we see exactly that:
$ grep "infrun.*\[Thread.*," testsuite/gdb.log | sort | uniq -c | sort -nr
70 infrun: 8798 [Thread 8798],
37 infrun: 8798 [Thread 8802],
36 infrun: 8798 [Thread 8804],
36 infrun: 8798 [Thread 8803],
35 infrun: 8798 [Thread 8805],
34 infrun: 8798 [Thread 8806],
The first column shows the number of times the target reported an
event for that thread, from:
infrun: target_wait (-1, status) =
infrun: 8798 [Thread 8798],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
This masks out the PR10116 issue.
However, if the target is better at giving equal priority to all
threads, the PR10116 issue happens often, so it may take quite a while
for the right thread to be the first to report its watchpoint event
just after the memory being watched really changed, resulting in test
time outs.
Here's the number of events handled for each thread on a gdbserver run
with the event fairness patches:
$ grep "infrun.*\[Thread.*," gdb.log | sort | uniq -c
2961 infrun: 13591 [Thread 13591],
2956 infrun: 13591 [Thread 13595],
2941 infrun: 13591 [Thread 13596],
2932 infrun: 13591 [Thread 13597],
2905 infrun: 13591 [Thread 13598],
2891 infrun: 13591 [Thread 13599],
Note how the number of events is much higher. The test routinely
takes over 10 seconds to finish on my machine rather than under a
second as with unpatched gdbserver, when it succeeds, but often it'll
fail with timeouts too.
So to make the test robust, this patch switches the tests to using
"awatch" instead of "watch", as access watchpoints don't care about
the watchpoint's "old value". With this, the test always finishes
quickly, and we can even bump the number of threads concurrently
writting to the shared variable, to have better assurance we're really
testing the case of the "wrong" thread triggering a watchpoint.
Here's the number of events I see for each thread on a run on my
machine, with a gdbserver patched with the event fairness series:
$ grep "infrun.*\[Thread.*," testsuite/gdb.log | sort | uniq -c
5 infrun: 5298 [Thread 5302],
4 infrun: 5298 [Thread 5303],
4 infrun: 5298 [Thread 5304],
4 infrun: 5298 [Thread 5305],
4 infrun: 5298 [Thread 5306],
4 infrun: 5298 [Thread 5307],
4 infrun: 5298 [Thread 5308],
4 infrun: 5298 [Thread 5309],
4 infrun: 5298 [Thread 5310],
4 infrun: 5298 [Thread 5311],
4 infrun: 5298 [Thread 5312],
4 infrun: 5298 [Thread 5313],
4 infrun: 5298 [Thread 5314],
4 infrun: 5298 [Thread 5315],
4 infrun: 5298 [Thread 5316],
gdb/testsuite/
2015-01-09 Pedro Alves <palves@redhat.com>
* gdb.base/annota1.exp (thread_test): Use srcfile and binfile from
the global scope. Set a breakpoint after all threads are started
rather than stepping over two source lines. Expect the prompt.
* gdb.base/watch_thread_num.c (threads_started_barrier): New
global.
(NUM): Now 15.
(main): Use threads_started_barrier to wait for all threads to
start. Main thread no longer calls thread_function. Exit after
180 seconds.
(loop): New function.
(thread_function): Wait on threads_started_barrier barrier. Call
'loop' at each iteration.
* gdb.base/watch_thread_num.exp: Continue to breakpoint after all
threads have started, instead of hardcoding number of "next"
steps. Use an access watchpoint instead of a write watchpoint.
These three test all spawn a few threads and then send a SIGSTOP to
their parent GDB in order to pause it while the new threads set things
up for the test. With a GDB patch that changes the inferior thread's
scheduling a bit, I sometimes see:
FAIL: gdb.threads/siginfo-threads.exp: catch signal 0 (timeout)
...
FAIL: gdb.threads/watchthreads-reorder.exp: reorder1: continue a (timeout)
...
FAIL: gdb.threads/ia64-sigill.exp: continue (timeout)
...
The issue is that the test program stops GDB before it had a chance of
processing the new thread's clone event:
(gdb) PASS: gdb.threads/siginfo-threads.exp: get pid
continue
Continuing.
Stopping GDB PID 21541.
Waiting till the threads initialize their TIDs.
FAIL: gdb.threads/siginfo-threads.exp: catch signal 0 (timeout)
On Linux (at least), new threads start stopped, and the debugger must
resume them. The fix is to make the test program wait for the new
threads to be running before stopping GDB.
gdb/testsuite/
2015-01-09 Pedro Alves <palves@redhat.com>
* gdb.threads/ia64-sigill.c (threads_started_barrier): New global.
(thread_func): Wait on barrier.
(main): Wait for all threads to start before stopping GDB.
* gdb.threads/siginfo-threads.c (threads_started_barrier): New
global.
(thread1_func, thread2_func): Wait on barrier.
(main): Wait for all threads to start before stopping GDB.
* gdb.threads/watchthreads-reorder.c (threads_started_barrier):
New global.
(thread1_func, thread2_func): Wait on barrier.
(main): Wait for all threads to start before stopping GDB.
Before the previous fixes, on Linux, this would trigger several
different problems, like:
[New LWP 27106]
[New LWP 27047]
warning: unable to open /proc file '/proc/-1/status'
[New LWP 27813]
[New LWP 27869]
warning: Can't attach LWP 11962: No child processes
Warning: couldn't activate thread debugging using libthread_db: Cannot find new threads: debugger service failed
warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.
gdb/testsuite/
2015-01-09 Pedro Alves <palves@redhat.com>
* gdb.threads/attach-many-short-lived-threads.c: New file.
* gdb.threads/attach-many-short-lived-threads.exp: New file.
[A test I wrote stumbled on a libthread_db issue related to thread
event breakpoints. See glibc PR17705:
[nptl_db: stale thread create/death events if debugger detaches]
https://sourceware.org/bugzilla/show_bug.cgi?id=17705
This patch avoids that whole issue by making GDB stop using thread
event breakpoints in the first place, which is good for other reasons
as well, anyway.]
Before PTRACE_EVENT_CLONE (Linux 2.6), the only way to learn about new
threads in the inferior (to attach to them) or to learn about thread
exit was to coordinate with the inferior's glibc/runtime, using
libthread_db. That works by putting a breakpoint at a magic address
which is called when a new thread is spawned, or when a thread is
about to exit. When that breakpoint is hit, all threads are stopped,
and then GDB coordinates with libthread_db to read data structures out
of the inferior to learn about what happened. Then the breakpoint is
single-stepped, and then all threads are re-resumed. This isn't very
efficient (stops all threads) and is more fragile (inferior's thread
list in memory may be corrupt; libthread_db bugs, etc.) than ideal.
When the kernel supports PTRACE_EVENT_CLONE (which we already make use
of), there's really no need to use libthread_db's event reporting
mechanism to learn about new LWPs. And if the kernel supports that,
then we learn about LWP exits through regular WIFEXITED wait statuses,
so no need for the death event breakpoint either.
GDBserver has been likewise skipping the thread_db events for a long
while:
https://sourceware.org/ml/gdb-patches/2007-10/msg00547.html
There's one user-visible difference: we'll no longer print about
threads being created and exiting while the program is running, like:
[Thread 0x7ffff7dbb700 (LWP 30670) exited]
[New Thread 0x7ffff7db3700 (LWP 30671)]
[Thread 0x7ffff7dd3700 (LWP 30667) exited]
[New Thread 0x7ffff7dab700 (LWP 30672)]
[Thread 0x7ffff7db3700 (LWP 30671) exited]
[Thread 0x7ffff7dcb700 (LWP 30668) exited]
This is exactly the same behavior as when debugging against remote
targets / gdbserver. I actually think that's a good thing (and as
such have listed this in the local/remote parity wiki page a while
ago), as the printing slows down the inferior. It's also a
distraction to keep bothering the user about short-lived threads that
she won't be able to interact with anyway. Instead, the user (and
frontend) will be informed about new threads that currently exist in
the program when the program next stops:
(gdb) c
...
* ctrl-c *
[New Thread 0x7ffff7963700 (LWP 7797)]
[New Thread 0x7ffff796b700 (LWP 7796)]
Program received signal SIGINT, Interrupt.
[Switching to Thread 0x7ffff796b700 (LWP 7796)]
clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:81
81 testq %rax,%rax
(gdb) info threads
A couple of tests had assumptions on GDB thread numbers that no longer
hold.
Tested on x86_64 Fedora 20.
gdb/
2014-01-09 Pedro Alves <palves@redhat.com>
Skip enabling event reporting if the kernel supports
PTRACE_EVENT_CLONE.
* linux-thread-db.c: Include "nat/linux-ptrace.h".
(thread_db_use_events): New function.
(try_thread_db_load_1): Check thread_db_use_events before enabling
event reporting.
(update_thread_state): New function.
(attach_thread): Use it. Check thread_db_use_events before
enabling event reporting.
(thread_db_detach): Check thread_db_use_events before disabling
event reporting.
(find_new_threads_callback): Check thread_db_use_events before
enabling event reporting. Update the thread's state if not using
libthread_db events.
gdb/testsuite/
2014-01-09 Pedro Alves <palves@redhat.com>
* gdb.threads/fork-thread-pending.exp: Switch to the main thread
instead of to thread 2.
* gdb.threads/signal-command-multiple-signals-pending.c (main):
Add barrier around each pthread_create call instead of around all
calls.
* gdb.threads/signal-command-multiple-signals-pending.exp (test):
Set a break on thread_function and have the child threads hit it
one at at a time.
We already skip "attach" tests if the target board is remote, in
dejagnu's sense, as we use TCL's exec to spawn the program on the
build machine. We should also skip these tests if testing with
"target remote" or other stub-like targets where "attach" doesn't make
sense.
Add a helper procedure that centralizes the checks a test that needs
to spawn a program for testing "attach" and make all test files that
use spawn_wait_for_attach check it.
gdb/testsuite/
2015-01-09 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (can_spawn_for_attach): New procedure.
(spawn_wait_for_attach): Error out if can_spawn_for_attach returns
false.
* gdb.base/attach.exp: Use can_spawn_for_attach instead of
checking whether the target board is remote.
* gdb.multi/multi-attach.exp: Likewise.
* gdb.python/py-sync-interp.exp: Likewise.
* gdb.server/ext-attach.exp: Likewise.
* gdb.python/py-prompt.exp: Use can_spawn_for_attach before the
tests that need to attach, instead of checking whether the target
board is remote at the top of the file.
The test entry-values.exp doesn't recognize the call instructions
on MIPS, such as JAL, JALS and etc, so this patch sets call_insn
to match various jump and branch instructions first.
Currently, we assume the next instruction address of call instruction
is the address returned from foo, however it is not correct on MIPS
which has delay slot. We extend variable call_insn to match one
instruction after jump or branch instruction, so that
$returned_from_foo is correct on MIPS.
All tests in entry-values.exp are PASS.
gdb/testsuite:
2015-01-08 Yao Qi <yao@codesourcery.com>
* gdb.trace/entry-values.exp: Set call_insn for MIPS target.
The following python command fails:
(gdb) python print gdb.lookup_type('char').array(1, 0)
Traceback (most recent call last):
File "<string>", line 1, in <module>
ValueError: Array length must not be negative
Error while executing Python code.
The above is trying to create an empty array, which is fairly command
in Ada.
gdb/ChangeLog:
* python/py-type.c (typy_array_1): Do not raise negative-length
exception if N2 is equal to N1 - 1.
gdb/testsuite/ChangeLog:
* gdb.python/py-type.exp: Add a couple test about empty
array creation, and negative-length array creation.
This patch is to clean up gdb.trace/entry-values.exp as a preparation
of the next patch. It updates the comments to reflect the code.
One DIE generated in dwarf assembler is
GNU_call_site {
{low_pc "$bar_start + $bar_call_foo" addr}
{abstract_origin :$foo_label}
the DW_AT_low_pc attribute is the return address after the call, so I
rename variable bar_call_foo to returned_from_foo.
gdb/testsuite:
2014-12-29 Yao Qi <yao@codesourcery.com>
* gdb.trace/entry-values.exp: Update comments. Rename variable
bar_call_foo to returned_from_foo.
