When stepping over a breakpoint with displaced stepping, GDB needs to
be informed if the stepped thread exits, otherwise the displaced
stepping buffer that was allocated to that thread leaks, and this can
result in deadlock, with other threads waiting for their turn to
displaced step, but their turn never comes.
Similarly, when stepping over a breakpoint in line, GDB also needs to
be informed if the stepped thread exits, so that is can clear the step
over state and re-resume threads.
This commit makes it possible for GDB to ask the target to report
thread exit events for a given thread, using the new "thread options"
mechanism introduced by a previous patch.
This only adds the core bits. Following patches in the series will
teach the Linux backends (native & gdbserver) to handle the
GDB_THREAD_OPTION_EXIT option, and then a later patch will make use of
these thread exit events to clean up displaced stepping and inline
stepping state properly.
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
Change-Id: I96b719fdf7fee94709e98bb3a90751d8134f3a38
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=27338
A previous patch taught GDB about a new TARGET_WAITKIND_THREAD_CLONED
event kind, and made the Linux target report clone events.
A following patch will teach Linux GDBserver to do the same thing.
However, for remote debugging, it wouldn't be ideal for GDBserver to
report every clone event to GDB, when GDB only cares about such events
in some specific situations. Reporting clone events all the time
would be potentially chatty. We don't enable thread create/exit
events all the time for the same reason. Instead we have the
QThreadEvents packet. QThreadEvents is target-wide, though.
This patch makes GDB instead explicitly request that the target
reports clone events or not, on a per-thread basis.
In order to be able to do that with GDBserver, we need a new remote
protocol feature. Since a following patch will want to enable thread
exit events on per-thread basis too, the packet introduced here is
more generic than just for clone events. It lets you enable/disable a
set of options at once, modelled on Linux ptrace's PTRACE_SETOPTIONS.
IOW, this commit introduces a new QThreadOptions packet, that lets you
specify a set of per-thread event options you want to enable. The
packet accepts a list of options/thread-id pairs, similarly to vCont,
processed left to right, with the options field being a number
interpreted as a bit mask of options. The only option defined in this
commit is GDB_THREAD_OPTION_CLONE (0x1), which ask the remote target
to report clone events. Another patch later in the series will
introduce another option.
For example, this packet sets option "1" (clone events) on thread
p1000.2345:
QThreadOptions;1:p1000.2345
and this clears options for all threads of process 1000, and then sets
option "1" (clone events) on thread p1000.2345:
QThreadOptions;0:p1000.-1;1:p1000.2345
This clears options of all threads of all processes:
QThreadOptions;0
The target reports the set of supported options by including
"QThreadOptions=<supported options>" in its qSupported response.
infrun is then tweaked to enable GDB_THREAD_OPTION_CLONE when stepping
over a breakpoint.
Unlike PTRACE_SETOPTIONS, fork/vfork/clone children do NOT inherit
their parent's thread options. This is so that GDB can send e.g.,
"QThreadOptions;0;1:TID" without worrying about threads it doesn't
know about yet.
Documentation for this new remote protocol feature is included in a
documentation patch later in the series.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=19675
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=27830
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
Change-Id: Ie41e5093b2573f14cf6ac41b0b5804eba75be37e
(A good chunk of the problem statement in the commit log below is
Andrew's, adjusted for a different solution, and for covering
displaced stepping too. The testcase is mostly Andrew's too.)
This commit addresses bugs gdb/19675 and gdb/27830, which are about
stepping over a breakpoint set at a clone syscall instruction, one is
about displaced stepping, and the other about in-line stepping.
Currently, when a new thread is created through a clone syscall, GDB
sets the new thread running. With 'continue' this makes sense
(assuming no schedlock):
- all-stop mode, user issues 'continue', all threads are set running,
a newly created thread should also be set running.
- non-stop mode, user issues 'continue', other pre-existing threads
are not affected, but as the new thread is (sort-of) a child of the
thread the user asked to run, it makes sense that the new threads
should be created in the running state.
Similarly, if we are stopped at the clone syscall, and there's no
software breakpoint at this address, then the current behaviour is
fine:
- all-stop mode, user issues 'stepi', stepping will be done in place
(as there's no breakpoint to step over). While stepping the thread
of interest all the other threads will be allowed to continue. A
newly created thread will be set running, and then stopped once the
thread of interest has completed its step.
- non-stop mode, user issues 'stepi', stepping will be done in place
(as there's no breakpoint to step over). Other threads might be
running or stopped, but as with the continue case above, the new
thread will be created running. The only possible issue here is
that the new thread will be left running after the initial thread
has completed its stepi. The user would need to manually select
the thread and interrupt it, this might not be what the user
expects. However, this is not something this commit tries to
change.
The problem then is what happens when we try to step over a clone
syscall if there is a breakpoint at the syscall address.
- For both all-stop and non-stop modes, with in-line stepping:
+ user issues 'stepi',
+ [non-stop mode only] GDB stops all threads. In all-stop mode all
threads are already stopped.
+ GDB removes s/w breakpoint at syscall address,
+ GDB single steps just the thread of interest, all other threads
are left stopped,
+ New thread is created running,
+ Initial thread completes its step,
+ [non-stop mode only] GDB resumes all threads that it previously
stopped.
There are two problems in the in-line stepping scenario above:
1. The new thread might pass through the same code that the initial
thread is in (i.e. the clone syscall code), in which case it will
fail to hit the breakpoint in clone as this was removed so the
first thread can single step,
2. The new thread might trigger some other stop event before the
initial thread reports its step completion. If this happens we
end up triggering an assertion as GDB assumes that only the
thread being stepped should stop. The assert looks like this:
infrun.c:5899: internal-error: int finish_step_over(execution_control_state*): Assertion `ecs->event_thread->control.trap_expected' failed.
- For both all-stop and non-stop modes, with displaced stepping:
+ user issues 'stepi',
+ GDB starts the displaced step, moves thread's PC to the
out-of-line scratch pad, maybe adjusts registers,
+ GDB single steps the thread of interest, [non-stop mode only] all
other threads are left as they were, either running or stopped.
In all-stop, all other threads are left stopped.
+ New thread is created running,
+ Initial thread completes its step, GDB re-adjusts its PC,
restores/releases scratchpad,
+ [non-stop mode only] GDB resumes the thread, now past its
breakpoint.
+ [all-stop mode only] GDB resumes all threads.
There is one problem with the displaced stepping scenario above:
3. When the parent thread completed its step, GDB adjusted its PC,
but did not adjust the child's PC, thus that new child thread
will continue execution in the scratch pad, invoking undefined
behavior. If you're lucky, you see a crash. If unlucky, the
inferior gets silently corrupted.
What is needed is for GDB to have more control over whether the new
thread is created running or not. Issue #1 above requires that the
new thread not be allowed to run until the breakpoint has been
reinserted. The only way to guarantee this is if the new thread is
held in a stopped state until the single step has completed. Issue #3
above requires that GDB is informed of when a thread clones itself,
and of what is the child's ptid, so that GDB can fixup both the parent
and the child.
When looking for solutions to this problem I considered how GDB
handles fork/vfork as these have some of the same issues. The main
difference between fork/vfork and clone is that the clone events are
not reported back to core GDB. Instead, the clone event is handled
automatically in the target code and the child thread is immediately
set running.
Note we have support for requesting thread creation events out of the
target (TARGET_WAITKIND_THREAD_CREATED). However, those are reported
for the new/child thread. That would be sufficient to address in-line
stepping (issue #1), but not for displaced-stepping (issue #3). To
handle displaced-stepping, we need an event that is reported to the
_parent_ of the clone, as the information about the displaced step is
associated with the clone parent. TARGET_WAITKIND_THREAD_CREATED
includes no indication of which thread is the parent that spawned the
new child. In fact, for some targets, like e.g., Windows, it would be
impossible to know which thread that was, as thread creation there
doesn't work by "cloning".
The solution implemented here is to model clone on fork/vfork, and
introduce a new TARGET_WAITKIND_THREAD_CLONED event. This event is
similar to TARGET_WAITKIND_FORKED and TARGET_WAITKIND_VFORKED, except
that we end up with a new thread in the same process, instead of a new
thread of a new process. Like FORKED and VFORKED, THREAD_CLONED
waitstatuses have a child_ptid property, and the child is held stopped
until GDB explicitly resumes it. This addresses the in-line stepping
case (issues #1 and #2).
The infrun code that handles displaced stepping fixup for the child
after a fork/vfork event is thus reused for THREAD_CLONE, with some
minimal conditions added, addressing the displaced stepping case
(issue #3).
The native Linux backend is adjusted to unconditionally report
TARGET_WAITKIND_THREAD_CLONED events to the core.
Following the follow_fork model in core GDB, we introduce a
target_follow_clone target method, which is responsible for making the
new clone child visible to the rest of GDB.
Subsequent patches will add clone events support to the remote
protocol and gdbserver.
displaced_step_in_progress_thread becomes unused with this patch, but
a new use will reappear later in the series. To avoid deleting it and
readding it back, this patch marks it with attribute unused, and the
latter patch removes the attribute again. We need to do this because
the function is static, and with no callers, the compiler would warn,
(error with -Werror), breaking the build.
This adds a new gdb.threads/stepi-over-clone.exp testcase, which
exercises stepping over a clone syscall, with displaced stepping vs
inline stepping, and all-stop vs non-stop. We already test stepping
over clone syscalls with gdb.base/step-over-syscall.exp, but this test
uses pthreads, while the other test uses raw clone, and this one is
more thorough. The testcase passes on native GNU/Linux, but fails
against GDBserver. GDBserver will be fixed by a later patch in the
series.
Co-authored-by: Andrew Burgess <aburgess@redhat.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=19675
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=27830
Change-Id: I95c06024736384ae8542a67ed9fdf6534c325c8e
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
Currently, one use of target_waitstatus yields a warning:
target/waitstatus.h: In function 'void stop_all_threads()':
target/waitstatus.h:175:13: warning: 'ws.target_waitstatus::m_value' may be used uninitialized in this function [-Wmaybe-uninitialized]
175 | m_value = other.m_value;
| ~~~~~~~~^~~~~~~~~~~~~~~
This patch silences the warning. I tried the "volatile member"
approach that was used for gdb::optional, but that didn't work, so
this patch simply initializes the member.
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
While playing with some code creating target_waitstatus objects, I was
mildly annoyed by the fact that we can't just return a new
target_waitstatus object. We have to do:
target_waitstatus ws;
ws.set_exited (123);
return ws;
Make the setters return the "this" object as a reference, such that it's
possible to do:
return target_waitstatus ().set_exited (123);
I initially thought of adding static creation functions, which you would
use like:
return target_waitstatus::make_exited (123);
However, making the setters return a reference to the object achieves
pretty much the same thing, with less new code.
Change-Id: I45159b7f9fcd9db5b20603480e323020b14ed147
When introducing this code, I forgot that we had some macros for this.
Replace some "manual" pragma diagnostic with some DIAGNOSTIC_* macros,
provided by include/diagnostics.h.
In diagnostics.h:
- Add DIAGNOSTIC_ERROR, to enable a diagnostic at error level.
- Add DIAGNOSTIC_ERROR_SWITCH, to enable -Wswitch at error level, for
both gcc and clang.
Additionally, using DIAGNOSTIC_PUSH, DIAGNOSTIC_ERROR_SWITCH and
DIAGNOSTIC_POP seems to misbehave with g++ 4.8, where we see these
errors:
CXX ada-tasks.o
/home/smarchi/src/binutils-gdb/gdb/ada-tasks.c: In function void read_known_tasks():
/home/smarchi/src/binutils-gdb/gdb/ada-tasks.c:998:10: error: enumeration value ADA_TASKS_UNKNOWN not handled in switch [-Werror=switch]
switch (data->known_tasks_kind)
^
Because of the POP, the diagnostic should go back to being disabled,
since it was disabled in the beginning, but that's not what we see
here. Versions of GCC >= 5 compile correctly.
Work around this by making DIAGNOSTIC_ERROR_SWITCH a no-op for GCC < 5.
Note that this code (already as it exists in master today) enables
-Wswitch at the error level even if --disable-werror is passed. It
shouldn't be a problem, as it's not like a new enumerator will appear
out of nowhere and cause a build error if building with future
compilers. Still, for correctness, we would ideally want to ask the
compiler to enable -Wswitch at its default level (as if the user had
passed -Wswitch on the command-line). There doesn't seem to be a way to
do this.
Change-Id: Id33ebec3de39bd449409ea0bab59831289ffe82d
I would like to print target_waitkind values in debug messages, so I
think that a target_waitkind-to-string function would be useful. While
at it, use it in target_waitstatus::to_string. This changes the output
of target_waitstatus::to_string a bit, but I think it is for the better.
The debug messages will show a string matching exactly the
target_waitkind enumerator (minus the TARGET_WAITKIND prefix).
As a convenience, make string_appendf return the same reference to
string it got as a parameter. This allows doing this:
return string_appendf (str, "foo");
... keeping the code concise.
Change-Id: I383dffc9c78614e7d0668b1516073905e798eef7
Make target_waitstatus_to_string a "to_string" method of
target_waitstatus, a bit like we have ptid_t::to_string already. This
will save a bit of typing.
Change-Id: Id261b7a09fa9fa3c738abac131c191a6f9c13905
I stumbled on a bug caused by the fact that a code path read
target_waitstatus::value::sig (expecting it to contain a gdb_signal
value) while target_waitstatus::kind was TARGET_WAITKIND_FORKED. This
meant that the active union field was in fact
target_waitstatus::value::related_pid, and contained a ptid. The read
signal value was therefore garbage, and that caused GDB to crash soon
after. Or, since that GDB was built with ubsan, this nice error
message:
/home/simark/src/binutils-gdb/gdb/linux-nat.c:1271:12: runtime error: load of value 2686365, which is not a valid value for type 'gdb_signal'
Despite being a large-ish change, I think it would be nice to make
target_waitstatus safe against that kind of bug. As already done
elsewhere (e.g. dynamic_prop), validate that the type of value read from
the union matches what is supposed to be the active field.
- Make the kind and value of target_waitstatus private.
- Make the kind initialized to TARGET_WAITKIND_IGNORE on
target_waitstatus construction. This is what most users appear to do
explicitly.
- Add setters, one for each kind. Each setter takes as a parameter the
data associated to that kind, if any. This makes it impossible to
forget to attach the associated data.
- Add getters, one for each associated data type. Each getter
validates that the data type fetched by the user matches the wait
status kind.
- Change "integer" to "exit_status", "related_pid" to "child_ptid",
just because that's more precise terminology.
- Fix all users.
That last point is semi-mechanical. There are a lot of obvious changes,
but some less obvious ones. For example, it's not possible to set the
kind at some point and the associated data later, as some users did.
But in any case, the intent of the code should not change in this patch.
This was tested on x86-64 Linux (unix, native-gdbserver and
native-extended-gdbserver boards). It was built-tested on x86-64
FreeBSD, NetBSD, MinGW and macOS. The rest of the changes to native
files was done as a best effort. If I forgot any place to update in
these files, it should be easy to fix (unless the change happens to
reveal an actual bug).
Change-Id: I0ae967df1ff6e28de78abbe3ac9b4b2ff4ad03b7
Print the extra information contained in target_waitstatus for these
events. For TARGET_WAITKIND_{FORKED,VFORKED}, the extra information is
contained in related_pid, and is the ptid of the new process. For
TARGET_WAITKIND_EXECD, it,s the exec'd path name in execd_pathname.
Print it using the same format used for TARGET_WAITKIND_STOPPED and
others.
Here are sample outputs for all three events:
[infrun] print_target_wait_results: target_wait (-1.0.0 [process -1], status) =
[infrun] print_target_wait_results: 726890.726890.0 [process 726890],
[infrun] print_target_wait_results: status->kind = vforked, related_pid = 726894.726894.0
[infrun] print_target_wait_results: target_wait (-1.0.0 [process -1], status) =
[infrun] print_target_wait_results: 727045.727045.0 [process 727045],
[infrun] print_target_wait_results: status->kind = forked, related_pid = 727049.727049.0
[infrun] print_target_wait_results: target_wait (-1.0.0 [process -1], status) =
[infrun] print_target_wait_results: 727119.727119.0 [process 727119],
[infrun] print_target_wait_results: status->kind = execd, execd_pathname = /usr/bin/ls
Change-Id: I4416a74e3bf792a625a68bf26c51689e170f2184
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
The test gdb.threads/watchthreads-reorder.exp verifies that the
'set debug infrun 1' debug output does not crash GDB.
Under high load, the test can still cause a GDB internal error (see details
below).
This patch fixes this crash, and improves/factorises some wait kind traces.
Tested on debian/amd64 + run one test with 'set debug infrun 1'.
Changes compared to the first version:
* Handles the suggestions of Kevin to trace the relevant elements
of the wait status (this is done by calling target_waitstatus_to_string).
* Some other changes to factorise wait status tracing.
Note that using target_waitstatus_to_string instead of the 'locally printed'
status kind strings means that debug trace that was using strings such as:
"EXITED" or "TARGET_WAITKIND_EXITED"
will now use what is printed by target_waitstatus_to_string e.g.
"exited".
gdb/ChangeLog
2019-04-01 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* infrun.c (stop_all_threads): If debug_infrun, always
trace the wait status after wait_one, using
target_waitstatus_to_string and target_pid_to_str.
(handle_inferior_event): Replace various trace of
wait status kind by a single trace.
* gdb/gnu-nat.c (gnu_nat_target::wait): Replace local
wait status kind image by target_waitstatus_to_string.
* target/waitstatus.c (target_waitstatus_to_string): Fix
obsolete comment.
(top-gdb) bt
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#1 0x00007f3d54a0642a in __GI_abort () at abort.c:89
#2 0x0000555c24c60e66 in dump_core () at ../../fixleaks/gdb/utils.c:201
#3 0x0000555c24c63d49 in internal_vproblem(internal_problem *, const char *, int, const char *, typedef __va_list_tag __va_list_tag *) (problem=problem@entry=0x555c25338d40 <internal_error_problem>, file=<optimized out>, line=287,
fmt=<optimized out>, ap=<optimized out>) at ../../fixleaks/gdb/utils.c:411
#4 0x0000555c24c63eab in internal_verror (file=<optimized out>, line=<optimized out>, fmt=<optimized out>,
ap=<optimized out>) at ../../fixleaks/gdb/utils.c:436
#5 0x0000555c249e8c22 in internal_error (file=file@entry=0x555c24e0f2ad "../../fixleaks/gdb/inferior.c",
line=line@entry=287, fmt=<optimized out>) at ../../fixleaks/gdb/common/errors.c:55
#6 0x0000555c247d3f5c in find_inferior_pid (pid=<optimized out>) at ../../fixleaks/gdb/inferior.c:287
#7 0x0000555c24ad2248 in find_inferior_pid (pid=<optimized out>) at ../../fixleaks/gdb/inferior.c:302
#8 find_inferior_ptid (ptid=...) at ../../fixleaks/gdb/inferior.c:301
#9 0x0000555c24c35f25 in find_thread_ptid (ptid=...) at ../../fixleaks/gdb/thread.c:522
#10 0x0000555c24b0ab4d in thread_db_target::pid_to_str[abi:cxx11](ptid_t) (
this=0x555c2532e3e0 <the_thread_db_target>, ptid=...) at ../../fixleaks/gdb/linux-thread-db.c:1637
#11 0x0000555c24c2f420 in target_pid_to_str[abi:cxx11](ptid_t) (ptid=...) at ../../fixleaks/gdb/target.c:2083
#12 0x0000555c24ad9cab in stop_all_threads () at ../../fixleaks/gdb/infrun.c:4373
#13 0x0000555c24ada00f in stop_waiting (ecs=<optimized out>) at ../../fixleaks/gdb/infrun.c:7464
#14 0x0000555c24adc401 in process_event_stop_test (ecs=ecs@entry=0x7ffc9402d9d0) at ../../fixleaks/gdb/infrun.c:6181
...
(top-gdb) fr 12
#12 0x0000555c24ad9cab in stop_all_threads () at ../../fixleaks/gdb/infrun.c:4373
(top-gdb) p event_ptid
$5 = {m_pid = 25419, m_lwp = 25427, m_tid = 0}
(top-gdb) p ptid
$6 = {m_pid = 0, m_lwp = 0, m_tid = 0}
(top-gdb) p ws
$7 = {kind = TARGET_WAITKIND_THREAD_EXITED, value = {integer = 0, sig = GDB_SIGNAL_0, related_pid = {m_pid = 0,
m_lwp = 0, m_tid = 0}, execd_pathname = 0x0, syscall_number = 0}}
(top-gdb)
The gdb.log corresponding to the above crash is:
(gdb) PASS: gdb.threads/watchthreads-reorder.exp: reorder1: set debug infrun 1
continue
Continuing.
infrun: clear_proceed_status_thread (Thread 0x7ffff7fcfb40 (LWP 25419))
infrun: clear_proceed_status_thread (Thread 0x7ffff7310700 (LWP 25427))
infrun: clear_proceed_status_thread (Thread 0x7ffff6b0f700 (LWP 25428))
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming Thread 0x7ffff7fcfb40 (LWP 25419)
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0x7ffff7fcfb40 (LWP 25419)] at 0x7ffff7344317
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: proceed: resuming Thread 0x7ffff7310700 (LWP 25427)
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0x7ffff7310700 (LWP 25427)] at 0x5555555553d7
infrun: prepare_to_wait
infrun: proceed: resuming Thread 0x7ffff6b0f700 (LWP 25428)
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0x7ffff6b0f700 (LWP 25428)] at 0x5555555554c8
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: -1.0.0 [process -1],
infrun: status->kind = ignore
infrun: TARGET_WAITKIND_IGNORE
infrun: prepare_to_wait
Joining the threads.
[Thread 0x7ffff6b0f700 (LWP 25428) exited]
infrun: target_wait (-1.0.0, status) =
infrun: -1.0.0 [process -1],
infrun: status->kind = ignore
infrun: TARGET_WAITKIND_IGNORE
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 25419.25419.0 [Thread 0x7ffff7fcfb40 (LWP 25419)],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x555555555e50
infrun: context switch
infrun: Switching context from Thread 0x7ffff6b0f700 (LWP 25428) to Thread 0x7ffff7fcfb40 (LWP 25419)
infrun: BPSTAT_WHAT_STOP_NOISY
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: Thread 0x7ffff7fcfb40 (LWP 25419) not executing
infrun: Thread 0x7ffff7310700 (LWP 25427) executing, need stop
[Thread 0x7ffff7310700 (LWP 25427) exited]
infrun: target_wait (-1.0.0, status) =
infrun: 25419.25427.0 [LWP 25427],
infrun: status->kind = thread exited, status = 0
infrun: infrun_async(0)
../../fixleaks/gdb/inferior.c:287: internal-error: inferior* find_inferior_pid(int): Assertion `pid != 0' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) FAIL: gdb.threads/watchthreads-reorder.exp: reorder1: continue to breakpoint: break-at-exit (GDB internal error)
Resyncing due to internal error.
n
infrun: infrun_async(1)
This is a bug, please report it. For instructions, see:
<http://www.gnu.org/software/gdb/bugs/>.
infrun: infrun_async(0)
../../fixleaks/gdb/inferior.c:287: internal-error: inferior* find_inferior_pid(int): Assertion `pid != 0' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Create a core file of GDB? (y or n) y
While working on my other scripts to deal with gdb headers, I noticed
that some files were missing include guards. I wrote a script to add
the missing ones, but found that using the obvious names for the
guards ran into clashes -- for example, gdb/nat/linux-nat.h used
"LINUX_NAT_H", but this was also the script's choice for
gdb/linux-nat.h.
So, I changed the script to normalize all include guards in gdb. This
patch is the result.
As usual the script is available here:
https://github.com/tromey/gdb-refactoring-scripts
Tested by rebuilding; I also ran it through "Fedora-x86_64-m64" on the
buildbot.
gdb/ChangeLog
2019-02-07 Tom Tromey <tom@tromey.com>
* yy-remap.h: Add include guard.
* xtensa-tdep.h: Add include guard.
* xcoffread.h: Rename include guard.
* varobj-iter.h: Add include guard.
* tui/tui.h: Rename include guard.
* tui/tui-winsource.h: Rename include guard.
* tui/tui-wingeneral.h: Rename include guard.
* tui/tui-windata.h: Rename include guard.
* tui/tui-win.h: Rename include guard.
* tui/tui-stack.h: Rename include guard.
* tui/tui-source.h: Rename include guard.
* tui/tui-regs.h: Rename include guard.
* tui/tui-out.h: Rename include guard.
* tui/tui-layout.h: Rename include guard.
* tui/tui-io.h: Rename include guard.
* tui/tui-hooks.h: Rename include guard.
* tui/tui-file.h: Rename include guard.
* tui/tui-disasm.h: Rename include guard.
* tui/tui-data.h: Rename include guard.
* tui/tui-command.h: Rename include guard.
* tic6x-tdep.h: Add include guard.
* target/waitstatus.h: Rename include guard.
* target/wait.h: Rename include guard.
* target/target.h: Rename include guard.
* target/resume.h: Rename include guard.
* target-float.h: Rename include guard.
* stabsread.h: Add include guard.
* rs6000-tdep.h: Add include guard.
* riscv-fbsd-tdep.h: Add include guard.
* regformats/regdef.h: Rename include guard.
* record.h: Rename include guard.
* python/python.h: Rename include guard.
* python/python-internal.h: Rename include guard.
* python/py-stopevent.h: Rename include guard.
* python/py-ref.h: Rename include guard.
* python/py-record.h: Rename include guard.
* python/py-record-full.h: Rename include guard.
* python/py-record-btrace.h: Rename include guard.
* python/py-instruction.h: Rename include guard.
* python/py-events.h: Rename include guard.
* python/py-event.h: Rename include guard.
* procfs.h: Add include guard.
* proc-utils.h: Add include guard.
* p-lang.h: Add include guard.
* or1k-tdep.h: Rename include guard.
* observable.h: Rename include guard.
* nto-tdep.h: Rename include guard.
* nat/x86-linux.h: Rename include guard.
* nat/x86-linux-dregs.h: Rename include guard.
* nat/x86-gcc-cpuid.h: Add include guard.
* nat/x86-dregs.h: Rename include guard.
* nat/x86-cpuid.h: Rename include guard.
* nat/ppc-linux.h: Rename include guard.
* nat/mips-linux-watch.h: Rename include guard.
* nat/linux-waitpid.h: Rename include guard.
* nat/linux-ptrace.h: Rename include guard.
* nat/linux-procfs.h: Rename include guard.
* nat/linux-osdata.h: Rename include guard.
* nat/linux-nat.h: Rename include guard.
* nat/linux-namespaces.h: Rename include guard.
* nat/linux-btrace.h: Rename include guard.
* nat/glibc_thread_db.h: Rename include guard.
* nat/gdb_thread_db.h: Rename include guard.
* nat/gdb_ptrace.h: Rename include guard.
* nat/fork-inferior.h: Rename include guard.
* nat/amd64-linux-siginfo.h: Rename include guard.
* nat/aarch64-sve-linux-sigcontext.h: Rename include guard.
* nat/aarch64-sve-linux-ptrace.h: Rename include guard.
* nat/aarch64-linux.h: Rename include guard.
* nat/aarch64-linux-hw-point.h: Rename include guard.
* mn10300-tdep.h: Add include guard.
* mips-linux-tdep.h: Add include guard.
* mi/mi-parse.h: Rename include guard.
* mi/mi-out.h: Rename include guard.
* mi/mi-main.h: Rename include guard.
* mi/mi-interp.h: Rename include guard.
* mi/mi-getopt.h: Rename include guard.
* mi/mi-console.h: Rename include guard.
* mi/mi-common.h: Rename include guard.
* mi/mi-cmds.h: Rename include guard.
* mi/mi-cmd-break.h: Rename include guard.
* m2-lang.h: Add include guard.
* location.h: Rename include guard.
* linux-record.h: Rename include guard.
* linux-nat.h: Add include guard.
* linux-fork.h: Add include guard.
* i386-darwin-tdep.h: Rename include guard.
* hppa-linux-offsets.h: Add include guard.
* guile/guile.h: Rename include guard.
* guile/guile-internal.h: Rename include guard.
* gnu-nat.h: Rename include guard.
* gdb-stabs.h: Rename include guard.
* frv-tdep.h: Add include guard.
* f-lang.h: Add include guard.
* event-loop.h: Add include guard.
* darwin-nat.h: Rename include guard.
* cp-abi.h: Rename include guard.
* config/sparc/nm-sol2.h: Rename include guard.
* config/nm-nto.h: Rename include guard.
* config/nm-linux.h: Add include guard.
* config/i386/nm-i386gnu.h: Rename include guard.
* config/djgpp/nl_types.h: Rename include guard.
* config/djgpp/langinfo.h: Rename include guard.
* compile/gcc-cp-plugin.h: Add include guard.
* compile/gcc-c-plugin.h: Add include guard.
* compile/compile.h: Rename include guard.
* compile/compile-object-run.h: Rename include guard.
* compile/compile-object-load.h: Rename include guard.
* compile/compile-internal.h: Rename include guard.
* compile/compile-cplus.h: Rename include guard.
* compile/compile-c.h: Rename include guard.
* common/xml-utils.h: Rename include guard.
* common/x86-xstate.h: Rename include guard.
* common/version.h: Rename include guard.
* common/vec.h: Rename include guard.
* common/tdesc.h: Rename include guard.
* common/selftest.h: Rename include guard.
* common/scoped_restore.h: Rename include guard.
* common/scoped_mmap.h: Rename include guard.
* common/scoped_fd.h: Rename include guard.
* common/safe-iterator.h: Rename include guard.
* common/run-time-clock.h: Rename include guard.
* common/refcounted-object.h: Rename include guard.
* common/queue.h: Rename include guard.
* common/ptid.h: Rename include guard.
* common/print-utils.h: Rename include guard.
* common/preprocessor.h: Rename include guard.
* common/pathstuff.h: Rename include guard.
* common/observable.h: Rename include guard.
* common/netstuff.h: Rename include guard.
* common/job-control.h: Rename include guard.
* common/host-defs.h: Rename include guard.
* common/gdb_wait.h: Rename include guard.
* common/gdb_vecs.h: Rename include guard.
* common/gdb_unlinker.h: Rename include guard.
* common/gdb_unique_ptr.h: Rename include guard.
* common/gdb_tilde_expand.h: Rename include guard.
* common/gdb_sys_time.h: Rename include guard.
* common/gdb_string_view.h: Rename include guard.
* common/gdb_splay_tree.h: Rename include guard.
* common/gdb_setjmp.h: Rename include guard.
* common/gdb_ref_ptr.h: Rename include guard.
* common/gdb_optional.h: Rename include guard.
* common/gdb_locale.h: Rename include guard.
* common/gdb_assert.h: Rename include guard.
* common/filtered-iterator.h: Rename include guard.
* common/filestuff.h: Rename include guard.
* common/fileio.h: Rename include guard.
* common/environ.h: Rename include guard.
* common/common-utils.h: Rename include guard.
* common/common-types.h: Rename include guard.
* common/common-regcache.h: Rename include guard.
* common/common-inferior.h: Rename include guard.
* common/common-gdbthread.h: Rename include guard.
* common/common-exceptions.h: Rename include guard.
* common/common-defs.h: Rename include guard.
* common/common-debug.h: Rename include guard.
* common/cleanups.h: Rename include guard.
* common/buffer.h: Rename include guard.
* common/btrace-common.h: Rename include guard.
* common/break-common.h: Rename include guard.
* cli/cli-utils.h: Rename include guard.
* cli/cli-style.h: Rename include guard.
* cli/cli-setshow.h: Rename include guard.
* cli/cli-script.h: Rename include guard.
* cli/cli-interp.h: Rename include guard.
* cli/cli-decode.h: Rename include guard.
* cli/cli-cmds.h: Rename include guard.
* charset-list.h: Add include guard.
* buildsym-legacy.h: Rename include guard.
* bfin-tdep.h: Add include guard.
* ax.h: Rename include guard.
* arm-linux-tdep.h: Add include guard.
* arm-fbsd-tdep.h: Add include guard.
* arch/xtensa.h: Rename include guard.
* arch/tic6x.h: Add include guard.
* arch/i386.h: Add include guard.
* arch/arm.h: Rename include guard.
* arch/arm-linux.h: Rename include guard.
* arch/arm-get-next-pcs.h: Rename include guard.
* arch/amd64.h: Add include guard.
* arch/aarch64-insn.h: Rename include guard.
* arch-utils.h: Rename include guard.
* annotate.h: Add include guard.
* amd64-darwin-tdep.h: Rename include guard.
* aarch64-linux-tdep.h: Add include guard.
* aarch64-fbsd-tdep.h: Add include guard.
* aarch32-linux-nat.h: Add include guard.
gdb/gdbserver/ChangeLog
2019-02-07 Tom Tromey <tom@tromey.com>
* x86-tdesc.h: Rename include guard.
* x86-low.h: Add include guard.
* wincecompat.h: Rename include guard.
* win32-low.h: Add include guard.
* utils.h: Rename include guard.
* tracepoint.h: Rename include guard.
* tdesc.h: Rename include guard.
* target.h: Rename include guard.
* server.h: Rename include guard.
* remote-utils.h: Rename include guard.
* regcache.h: Rename include guard.
* nto-low.h: Rename include guard.
* notif.h: Add include guard.
* mem-break.h: Rename include guard.
* lynx-low.h: Add include guard.
* linux-x86-tdesc.h: Add include guard.
* linux-s390-tdesc.h: Add include guard.
* linux-ppc-tdesc-init.h: Add include guard.
* linux-low.h: Add include guard.
* linux-aarch64-tdesc.h: Add include guard.
* linux-aarch32-low.h: Add include guard.
* inferiors.h: Rename include guard.
* i387-fp.h: Rename include guard.
* hostio.h: Rename include guard.
* gdbthread.h: Rename include guard.
* gdb_proc_service.h: Rename include guard.
* event-loop.h: Rename include guard.
* dll.h: Rename include guard.
* debug.h: Rename include guard.
* ax.h: Rename include guard.
This commit applies all changes made after running the gdb/copyright.py
script.
Note that one file was flagged by the script, due to an invalid
copyright header
(gdb/unittests/basic_string_view/element_access/char/empty.cc).
As the file was copied from GCC's libstdc++-v3 testsuite, this commit
leaves this file untouched for the time being; a patch to fix the header
was sent to gcc-patches first.
gdb/ChangeLog:
Update copyright year range in all GDB files.
In my multi-target branch I ran into problems with GDB's terminal
handling that exist in master as well, with multi-inferior debugging.
This patch adds a testcase for said problems
(gdb.multi/multi-term-settings.exp), fixes the problems, fixes PR
gdb/13211 as well (and adds a testcase for that too,
gdb.base/interrupt-daemon.exp).
The basis of the problem I ran into is the following. Consider a
scenario where you have:
- inferior 1 - started with "attach", process is running on some
other terminal.
- inferior 2 - started with "run", process is sharing gdb's terminal.
In this scenario, when you stop/resume both inferiors, you want GDB to
save/restore the terminal settings of inferior 2, the one that is
sharing GDB's terminal. I.e., you want inferior 2 to "own" the
terminal (in target_terminal::is_ours/target_terminal::is_inferior
sense).
Unfortunately, that's not what you get currently. Because GDB doesn't
know whether an attached inferior is actually sharing GDB's terminal,
it tries to save/restore its settings anyway, ignoring errors. In
this case, this is pointless, because inferior 1 is running on a
different terminal, but GDB doesn't know better.
And then, because it is only possible to have the terminal settings of
a single inferior be in effect at a time, or make one inferior/pgrp be
the terminal's foreground pgrp (aka, only one inferior can "own" the
terminal, ignoring fork children here), if GDB happens to try to
restore the terminal settings of inferior 1 first, then GDB never
restores the terminal settings of inferior 2.
This patch fixes that and a few things more along the way:
- Moves enum target_terminal::terminal_state out of the
target_terminal class (it's currently private) and makes it a
scoped enum so that it can be easily used elsewhere.
- Replaces the inflow.c:terminal_is_ours boolean with a
target_terminal_state variable. This allows distinguishing is_ours
and is_ours_for_output states. This allows finally making
child_terminal_ours_1 do something with its "output_only"
parameter.
- Makes each inferior have its own copy of the
is_ours/is_ours_for_output/is_inferior state.
- Adds a way for GDB to tell whether the inferior is sharing GDB's
terminal. Works best on Linux and Solaris; the fallback works just
as well as currently.
- With that, we can remove the inf->attach_flag tests from
child_terminal_inferior/child_terminal_ours.
- Currently target_ops.to_ours is responsible for both saving the
current inferior's terminal state, and restoring gdb's state.
Because each inferior has its own terminal state (possibly handled
by different targets in a multi-target world, even), we need to
split the inferior-saving part from the gdb-restoring part. The
patch adds a new target_ops.to_save_inferior target method for
that.
- Adds a new target_terminal::save_inferior() function, so that
sequences like:
scoped_restore_terminal_state save_state;
target_terminal::ours_for_output ();
... restore back inferiors that were
target_terminal_state::is_inferior before back to is_inferior, and
leaves inferiors that were is_ours alone.
- Along the way, this adds a default implementation of
target_pass_ctrlc to inflow.c (for inf-child.c), that handles
passing the Ctrl-C to a process running on GDB's terminal or to
some other process otherwise.
- Similarly, adds a new target default implementation of
target_interrupt, for the "interrupt" command. The current
implementation of this hook in inf-ptrace.c kills the whole process
group, but that's incorrect/undesirable because we may not be
attached to all processes in the process group. And also, it's
incorrect because inferior_process_group() doesn't really return
the inferior's real process group id if the inferior is not a
process group leader... This is the cause of PR gdb/13211 [1],
which this patch fixes. While at it, that target method's "ptid"
parameter is eliminated, because it's not really used.
- A new test is included that exercises and fixes PR gdb/13211, and
also fixes a GDB issue reported on stackoverflow that I ran into
while working on this [2]. The problem is similar to PR gdb/13211,
except that it also triggers with Ctrl-C. When debugging a daemon
(i.e., a process that disconnects from the controlling terminal and
is not a process group leader, then Ctrl-C doesn't work, you just
can't interrupt the inferior at all, resulting in a hung debug
session. The problem is that since the inferior is no longer
associated with gdb's session / controlling terminal, then trying
to put the inferior in the foreground fails. And so Ctrl-C never
reaches the inferior directly. pass_signal is only used when the
inferior is attached, but that is not the case here. This is fixed
by the new child_pass_ctrlc. Without the fix, the new
interrupt-daemon.exp testcase fails with timeout waiting for a
SIGINT that never arrives.
[1] PR gdb/13211 - Async / Process group and interrupt not working
https://sourceware.org/bugzilla/show_bug.cgi?id=13211
[2] GDB not reacting Ctrl-C when after fork() and setsid()
https://stackoverflow.com/questions/46101292/gdb-not-reacting-ctrl-c-when-after-fork-and-setsid
Note this patch does _not_ fix:
- PR gdb/14559 - The 'interrupt' command does not work if sigwait is in use
https://sourceware.org/bugzilla/show_bug.cgi?id=14559
- PR gdb/9425 - When using "sigwait" GDB doesn't trap SIGINT. Ctrl+C terminates program when should break gdb.
https://sourceware.org/bugzilla/show_bug.cgi?id=9425
The only way to fix that that I know of (without changing the kernel)
is to make GDB put inferiors in a separate session (create a
pseudo-tty master/slave pair, make the inferior run with the slave as
its terminal, and have gdb pump output/input on the master end).
gdb/ChangeLog:
2018-01-30 Pedro Alves <palves@redhat.com>
PR gdb/13211
* config.in, configure: Regenerate.
* configure.ac: Check for getpgid.
* go32-nat.c (go32_pass_ctrlc): New.
(go32_target): Install it.
* inf-child.c (inf_child_target): Install
child_terminal_save_inferior, child_pass_ctrlc and
child_interrupt.
* inf-ptrace.c (inf_ptrace_interrupt): Delete.
(inf_ptrace_target): No longer install it.
* infcmd.c (interrupt_target_1): Adjust.
* inferior.h (child_terminal_save_inferior, child_pass_ctrlc)
(child_interrupt): Declare.
(inferior::terminal_state): New.
* inflow.c (struct terminal_info): Update comments.
(inferior_process_group): Delete.
(terminal_is_ours): Delete.
(gdb_tty_state): New.
(child_terminal_init): Adjust.
(is_gdb_terminal, sharing_input_terminal_1)
(sharing_input_terminal): New functions.
(child_terminal_inferior): Adjust. Use sharing_input_terminal.
Set the process's actual process group in the foreground if
possible. Handle is_ours_for_output/is_ours distinction. Don't
mark terminal as the inferior's if not sharing GDB's terminal.
Don't check attach_flag.
(child_terminal_ours_for_output, child_terminal_ours): Adjust to
pass down a target_terminal_state.
(child_terminal_save_inferior): New, factored out from ...
(child_terminal_ours_1): ... this. Handle
target_terminal_state::is_ours_for_output.
(child_interrupt, child_pass_ctrlc): New.
(inflow_inferior_exit): Clear the inferior's terminal_state.
(copy_terminal_info): Copy the inferior's terminal state.
(_initialize_inflow): Remove reference to terminal_is_ours.
* inflow.h (inferior_process_group): Delete.
* nto-procfs.c (nto_handle_sigint, procfs_interrupt): Adjust.
* procfs.c (procfs_target): Don't install procfs_interrupt.
(procfs_interrupt): Delete.
* remote.c (remote_serial_quit_handler): Adjust.
(remote_interrupt): Remove ptid parameter. Adjust.
* target-delegates.c: Regenerate.
* target.c: Include "terminal.h".
(target_terminal::terminal_state): Rename to ...
(target_terminal::m_terminal_state): ... this.
(target_terminal::init): Adjust.
(target_terminal::inferior): Adjust to per-inferior
terminal_state.
(target_terminal::restore_inferior, target_terminal_is_ours_kind): New.
(target_terminal::ours, target_terminal::ours_for_output): Use
target_terminal_is_ours_kind.
(target_interrupt): Remove ptid parameter. Adjust.
(default_target_pass_ctrlc): Adjust.
* target.h (target_ops::to_terminal_save_inferior): New field.
(target_ops::to_interrupt): Remove ptid_t parameter.
(target_interrupt): Remove ptid_t parameter. Update comment.
(target_pass_ctrlc): Update comment.
* target/target.h (target_terminal_state): New scoped enum,
factored out of ...
(target_terminal::terminal_state): ... here.
(target_terminal::inferior): Update comments.
(target_terminal::restore_inferior): New.
(target_terminal::is_inferior, target_terminal::is_ours)
(target_terminal::is_ours_for_output): Adjust.
(target_terminal::scoped_restore_terminal_state): Adjust to
rename, and call restore_inferior() instead of inferior().
(target_terminal::scoped_restore_terminal_state::m_state): Change
type.
(target_terminal::terminal_state): Rename to ...
(target_terminal::m_terminal_state): ... this and change type.
gdb/gdbserver/ChangeLog:
2018-01-30 Pedro Alves <palves@redhat.com>
PR gdb/13211
* target.c (target_terminal::terminal_state): Rename to ...
(target_terminal::m_terminal_state): ... this.
gdb/testsuite/ChangeLog:
2018-01-30 Pedro Alves <palves@redhat.com>
PR gdb/13211
* gdb.base/interrupt-daemon.c: New.
* gdb.base/interrupt-daemon.exp: New.
* gdb.multi/multi-term-settings.c: New.
* gdb.multi/multi-term-settings.exp: New.
A quite straightforward change. It does "fix" leaks in record-btrace.c,
although since this is only used in debug printing code, it has no real
world impact.
gdb/ChangeLog:
* target/waitstatus.h (target_waitstatus_to_string): Change
return type to std::string.
* target/waitstatus.c (target_waitstatus_to_string): Return
std::string.
* target.h (target_waitstatus_to_string): Remove declaration.
* infrun.c (resume, clear_proceed_status_thread,
print_target_wait_results, do_target_wait, save_waitstatus,
stop_all_threads): Adjust.
* record-btrace.c (record_btrace_wait): Adjust.
* target-debug.h
(target_debug_print_struct_target_waitstatus_p): Adjust.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_wait_1): Adjust.
* server.c (queue_stop_reply_callback): Adjust.
This is the most important (and the biggest, sorry) patch of the
series. It moves fork_inferior from gdb/fork-child.c to
nat/fork-inferior.c and makes all the necessary adjustments to both
GDB and gdbserver to make sure everything works OK.
There is no "most important change" with this patch; all changes are
made in a progressive way, making sure that gdbserver had the
necessary features while not breaking GDB at the same time.
I decided to go ahead and implement a partial support for starting the
inferior with a shell on gdbserver, although the full feature comes in
the next patch. The user won't have the option to disable the
startup-with-shell, and also won't be able to change which shell
gdbserver will use (other than setting the $SHELL environment
variable, that is).
Everything is working as expected, and no regressions were present
during the tests.
gdb/ChangeLog:
2017-06-07 Sergio Durigan Junior <sergiodj@redhat.com>
Pedro Alves <palves@redhat.com>
* Makefile.in (HFILES_NO_SRCDIR): Add "common/common-inferior.h"
and "nat/fork-inferior.h".
* common/common-inferior.h: New file, with contents from
"gdb/inferior.h".
* commom/common-utils.c: Include "common-utils.h".
(stringify_argv): New function.
* common/common-utils.h (stringify_argv): New prototype.
* configure.nat: Add "fork-inferior.o" as a dependency for
"*linux*", "fbsd*" and "nbsd*" hosts.
* corefile.c (get_exec_file): Update comment.
* darwin-nat.c (darwin_ptrace_him): Call "gdb_startup_inferior"
instead of "startup_inferior".
(darwin_create_inferior): Call "add_thread_silent" after
"fork_inferior".
* fork-child.c: Cleanup unnecessary includes.
(SHELL_FILE): Move to "common/common-fork-child.c".
(environ): Likewise.
(exec_wrapper): Initialize.
(get_exec_wrapper): New function.
(breakup_args): Move to "common/common-fork-child.c"; rename to
"breakup_args_for_exec".
(escape_bang_in_quoted_argument): Move to
"common/common-fork-child.c".
(saved_ui): New variable.
(prefork_hook): New function.
(postfork_hook): Likewise.
(postfork_child_hook): Likewise.
(gdb_startup_inferior): Likewise.
(fork_inferior): Move to "common/common-fork-child.c". Update
function to support gdbserver.
(startup_inferior): Likewise.
* gdbcore.h (get_exec_file): Remove declaration.
* gnu-nat.c (gnu_create_inferior): Call "gdb_startup_inferior"
instead of "startup_inferior". Call "add_thread_silent" after
"fork_inferior".
* inf-ptrace.c: Include "nat/fork-inferior.h" and "utils.h".
(inf_ptrace_create_inferior): Call "gdb_startup_inferior"
instead of "startup_inferior". Call "add_thread_silent" after
"fork_inferior".
* inferior.h: Include "common-inferior.h".
(trace_start_error): Move to "common/common-utils.h".
(trace_start_error_with_name): Likewise.
(fork_inferior): Move prototype to "nat/fork-inferior.h".
(startup_inferior): Likewise.
(gdb_startup_inferior): New prototype.
* nat/fork-inferior.c: New file, with contents from "fork-child.c".
* nat/fork-inferior.h: New file.
* procfs.c (procfs_init_inferior): Call "gdb_startup_inferior"
instead of "startup_inferior". Call "add_thread_silent" after
"fork_inferior".
* target.h (target_terminal_init): Move prototype to
"target/target.h".
(target_terminal_inferior): Likewise.
(target_terminal_ours): Likewise.
* target/target.h (target_terminal_init): New prototype, moved
from "target.h".
(target_terminal_inferior): Likewise.
(target_terminal_ours): Likewise.
* utils.c (gdb_flush_out_err): New function.
gdb/gdbserver/ChangeLog:
2017-06-07 Sergio Durigan Junior <sergiodj@redhat.com>
Pedro Alves <palves@redhat.com>
* Makefile.in (SFILES): Add "nat/fork-inferior.o".
* configure: Regenerate.
* configure.srv (srv_linux_obj): Add "fork-child.o" and
"fork-inferior.o".
(i[34567]86-*-lynxos*): Likewise.
(spu*-*-*): Likewise.
* fork-child.c: New file.
* linux-low.c: Include "common-inferior.h", "nat/fork-inferior.h"
and "environ.h".
(linux_ptrace_fun): New function.
(linux_create_inferior): Adjust function prototype to reflect
change on "target.h". Adjust function code to use
"fork_inferior".
(linux_request_interrupt): Delete "signal_pid".
* lynx-low.c: Include "common-inferior.h" and "nat/fork-inferior.h".
(lynx_ptrace_fun): New function.
(lynx_create_inferior): Adjust function prototype to reflect
change on "target.h". Adjust function code to use
"fork_inferior".
* nto-low.c (nto_create_inferior): Adjust function prototype and
code to reflect change on "target.h". Update comments.
* server.c: Include "common-inferior.h", "nat/fork-inferior.h",
"common-terminal.h" and "environ.h".
(terminal_fd): Moved to fork-child.c.
(old_foreground_pgrp): Likewise.
(restore_old_foreground_pgrp): Likewise.
(last_status): Make it global.
(last_ptid): Likewise.
(our_environ): New variable.
(startup_with_shell): Likewise.
(program_name): Likewise.
(program_argv): Rename to...
(program_args): ...this.
(wrapper_argv): New variable.
(start_inferior): Delete function.
(get_exec_wrapper): New function.
(get_exec_file): Likewise.
(get_environ): Likewise.
(prefork_hook): Likewise.
(post_fork_inferior): Likewise.
(postfork_hook): Likewise.
(postfork_child_hook): Likewise.
(handle_v_run): Update code to deal with arguments coming from the
remote host. Update calls from "start_inferior" to
"create_inferior".
(captured_main): Likewise. Initialize environment variable. Call
"have_job_control".
* server.h (post_fork_inferior): New prototype.
(get_environ): Likewise.
(last_status): Declare.
(last_ptid): Likewise.
(signal_pid): Likewise.
* spu-low.c: Include "common-inferior.h" and "nat/fork-inferior.h".
(spu_ptrace_fun): New function.
(spu_create_inferior): Adjust function prototype to reflect change
on "target.h". Adjust function code to use "fork_inferior".
* target.c (target_terminal_init): New function.
(target_terminal_inferior): Likewise.
(target_terminal_ours): Likewise.
* target.h: Include <vector>.
(struct target_ops) <create_inferior>: Update prototype.
(create_inferior): Update macro.
* utils.c (gdb_flush_out_err): New function.
* win32-low.c (win32_create_inferior): Adjust function prototype
and code to reflect change on "target.h".
gdb/testsuite/ChangeLog:
2017-06-07 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.server/non-existing-program.exp: Update regex in order to
reflect the fact that gdbserver is now using fork_inferior (with a
shell) to startup the inferior.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This simple commit consolidates the API of
target_supports_multi_process. Since both GDB and gdbserver use the
same function prototype, all that was needed was to move create this
prototype on gdb/target/target.h and turn the macros declared on
gdb/{,gdbserver/}target.h into actual functions.
Regtested (clean pass) on the BuildBot.
gdb/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
* target/target.h (target_supports_multi_process): New prototype.
gdb/gdbserver/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
This patch consolidates the API of target_mourn_inferior between GDB
and gdbserver, in my continuing efforts to make sharing the
fork_inferior function possible between both.
GDB's version of the function did not care about the inferior's ptid
being mourned, but gdbserver's needed to know this information. Since
it actually makes sense to pass the ptid as an argument, instead of
depending on a global value directly (which GDB's version did), I
decided to make the generic API to accept it. I then went on and
extended all calls being made on GDB to include a ptid argument (which
ended up being inferior_ptid most of the times, anyway), and now we
have a more sane interface.
On GDB's side, after talking to Pedro a bit about it, we decided that
just an assertion to make sure that the ptid being passed is equal to
inferior_ptid would be enough for now, on the GDB side. We can remove
the assertion and perform more operations later if we ever pass
anything different than inferior_ptid.
Regression tested on our BuildBot, everything OK.
I'd appreciate a special look at gdb/windows-nat.c's modification
because I wasn't really sure what to do there. It seemed to me that
maybe I should build a ptid out of the process information there, but
then I am almost sure the assertion on GDB's side would trigger.
gdb/ChangeLog:
2016-09-19 Sergio Durigan Junior <sergiodj@redhat.com>
* darwin-nat.c (darwin_kill_inferior): Adjusting call to
target_mourn_inferior to include ptid_t argument.
* fork-child.c (startup_inferior): Likewise.
* gnu-nat.c (gnu_kill_inferior): Likewise.
* inf-ptrace.c (inf_ptrace_kill): Likewise.
* infrun.c (handle_inferior_event_1): Likewise.
* linux-nat.c (linux_nat_attach): Likewise.
(linux_nat_kill): Likewise.
* nto-procfs.c (interrupt_query): Likewise.
(procfs_interrupt): Likewise.
(procfs_kill_inferior): Likewise.
* procfs.c (procfs_kill_inferior): Likewise.
* record.c (record_mourn_inferior): Likewise.
* remote-sim.c (gdbsim_kill): Likewise.
* remote.c (remote_detach_1): Likewise.
(remote_kill): Likewise.
* target.c (target_mourn_inferior): Change declaration to accept
new ptid_t argument; use gdb_assert on it.
* target.h (target_mourn_inferior): Move function prototype from
here...
* target/target.h (target_mourn_inferior): ... to here. Adjust it
to accept new ptid_t argument.
* windows-nat.c (get_windows_debug_event): Adjusting call to
target_mourn_inferior to include ptid_t argument.
gdb/gdbserver/ChangeLog:
2016-09-19 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c (start_inferior): Call target_mourn_inferior instead of
mourn_inferior; pass ptid_t argument to it.
(resume): Likewise.
(handle_target_event): Likewise.
* target.c (target_mourn_inferior): New function.
* target.h (mourn_inferior): Delete macro.
This commit moves the target_wait prototype from the GDB-specific
target.h header to the common target/target.h header. Then, it
creates a compatible implementation of target_wait on gdbserver using
the_target->wait, and adjusts the (only) caller (mywait function).
Pretty straightforward, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (mywait): Call target_wait instead of
the_target->wait.
(target_wait): New function.
gdb/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_wait): Mention that the function's prototype
can be found at target/target.h.
* target.h (target_wait): Move prototype from here...
* target/target.h (target_wait): ... to here.
This commit implements a new function, target_continue, on top of the
target_resume function. Then, it replaces all calls to target_resume
by calls to target_continue or to the already existing
target_continue_no_signal.
This is one of the (many) necessary steps needed to consolidate the
target interface between GDB and gdbserver. In particular, I am
interested in the impact this change will have on the unification of
the fork_inferior function (which I have been working on).
Tested on the BuildBot, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c (start_inferior): New variable 'ptid'. Replace calls
to the_target->resume by target_continue{,_no_signal}, depending
on the case.
* target.c (target_stop_and_wait): Call target_continue_no_signal
instead of the_target->resume.
(target_continue): New function.
gdb/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* fork-child.c (startup_inferior): Replace calls to target_resume
by target_continue{,_no_signal}, depending on the case.
* linux-nat.c (cleanup_target_stop): Call
target_continue_no_signal instead of target_resume.
* procfs.c (procfs_wait): Likewise.
* target.c (target_continue): New function.
* target/target.h (target_continue): New prototype.
When testing with "maint set target-non-stop on", a few
threading-related tests expose an issue that requires new RSP packets.
Say there are 3 threads running, 1-3. If GDB tries to stop thread 1,
2 and 3, and then waits for their stops, but meanwhile say, thread 2
exits, GDB hangs forever waiting for a stop for thread 2 that won't
ever happen.
This patch fixes the issue by adding support for thread exit events to
the protocol. However, we don't want these always enabled, as they're
useless most of the time, and would slow down remote debugging. So I
made it so that GDB can enable/disable them, and then made gdb do that
around the cases that need it, which currently is only
infrun.c:stop_all_threads.
In turn, if we have thread exit events, then the extra "thread x
exited" traffic slows down attach-many-short-lived-threads.exp enough
that gdb has trouble keeping up with new threads that are spawned
while gdb tries to stop existing ones. To fix that I added support
for the counterpart thread created events too. Enabling those when we
try to stop threads ensures that new threads never get a chance to
themselves start new threads, killing the race.
gdb/doc/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Remote Configuration): List "set/show remote
thread-events" command in configuration table.
(Stop Reply Packets): Document "T05 create" stop
reason and 'w' stop reply.
(General Query Packets): Document QThreadEvents packet. Document
QThreadEvents qSupported feature.
gdb/gdbserver/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* linux-low.c (handle_extended_wait): Assert that the LWP's
waitstatus is TARGET_WAITKIND_IGNORE. If GDB wants to hear about
thread create events, leave the new child's status pending.
(linux_low_filter_event): If GDB wants to hear about thread exit
events, leave the LWP marked dead and don't delete it.
(linux_wait_for_event_filtered): Don't check for thread exit.
(filter_exit_event): New function.
(linux_wait_1): Use it, when returning an exit event.
(linux_resume_one_lwp_throw): Assert that the LWP's
waitstatus is TARGET_WAITKIND_IGNORE.
* remote-utils.c (prepare_resume_reply): Handle
TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED.
* server.c (report_thread_events): New global.
(handle_general_set): Handle QThreadEvents.
(handle_query) <qSupported>: Handle and report QThreadEvents+;
(handle_target_event): Handle TARGET_WAITKIND_THREAD_CREATED and
TARGET_WAITKIND_THREAD_EXITED.
* server.h (report_thread_events): Declare.
gdb/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* NEWS (New commands): Mention "set/show remote thread-events"
commands.
(New remote packets): Mention thread created/exited stop reasons
and QThreadEvents packet.
* infrun.c (disable_thread_events): New function.
(stop_all_threads): Disable/enable thread create/exit events.
Handle TARGET_WAITKIND_THREAD_EXITED.
(handle_inferior_event_1): Handle TARGET_WAITKIND_THREAD_CREATED
and TARGET_WAITKIND_THREAD_EXITED.
* remote.c (remove_child_of_pending_fork): Also remove threads of
threads that have TARGET_WAITKIND_THREAD_EXITED events.
(remote_parse_stop_reply): Handle "create" magic register. Handle
'w' stop reply.
(initialize_remote): Install remote_thread_events as
to_thread_events target hook.
(remote_thread_events): New function.
* target-delegates.c: Regenerate.
* target.c (target_thread_events): New function.
* target.h (struct target_ops) <to_thread_events>: New field.
(target_thread_events): Declare.
* target/waitstatus.c (target_waitstatus_to_string): Handle
TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED.
* target/waitstatus.h (enum target_waitkind)
<TARGET_WAITKIND_THREAD_CREATED, TARGET_WAITKIND_THREAD_EXITED):
New values.
Ref: https://sourceware.org/ml/gdb-patches/2015-07/msg00868.html
This adds a test that has a multithreaded program have several threads
continuously fork, while another thread continuously steps over a
breakpoint.
This exposes several intertwined issues, which this patch addresses:
- When we're stopping and suspending threads, some thread may fork,
and we missed setting its suspend count to 1, like we do when a new
clone/thread is detected. When we next unsuspend threads, the fork
child's suspend count goes below 0, which is bogus and fails an
assertion.
- If a step-over is cancelled because a signal arrives, but then gdb
is not interested in the signal, we pass the signal straight back
to the inferior. However, we miss that we need to re-increment the
suspend counts of all other threads that had been paused for the
step-over. As a result, other threads indefinitely end up stuck
stopped.
- If a detach request comes in just while gdbserver is handling a
step-over (in the test at hand, this is GDB detaching the fork
child), gdbserver internal errors in stabilize_thread's helpers,
which assert that all thread's suspend counts are 0 (otherwise we
wouldn't be able to move threads out of the jump pads). The
suspend counts aren't 0 while a step-over is in progress, because
all threads but the one stepping past the breakpoint must remain
paused until the step-over finishes and the breakpoint can be
reinserted.
- Occasionally, we see "BAD - reinserting but not stepping." being
output (from within linux_resume_one_lwp_throw). That was because
GDB pokes memory while gdbserver is busy with a step-over, and that
suspends threads, and then re-resumes them with proceed_one_lwp,
which missed another reason to tell linux_resume_one_lwp that the
thread should be set back to stepping.
- In a couple places, we were resuming threads that are meant to be
suspended. E.g., when a vCont;c/s request for thread B comes in
just while gdbserver is stepping thread A past a breakpoint. The
resume for thread B must be deferred until the step-over finishes.
- The test runs with both "set detach-on-fork" on and off. When off,
it exercises the case of GDB detaching the fork child explicitly.
When on, it exercises the case of gdb resuming the child
explicitly. In the "off" case, gdb seems to exponentially become
slower as new inferiors are created. This is _very_ noticeable as
with only 100 inferiors gdb is crawling already, which makes the
test take quite a bit to run. For that reason, I've disabled the
"off" variant for now.
gdb/ChangeLog:
2015-08-06 Pedro Alves <palves@redhat.com>
* target/waitstatus.h (enum target_stop_reason)
<TARGET_STOPPED_BY_SINGLE_STEP>: New value.
gdb/gdbserver/ChangeLog:
2015-08-06 Pedro Alves <palves@redhat.com>
* linux-low.c (handle_extended_wait): Set the fork child's suspend
count if stopping and suspending threads.
(check_stopped_by_breakpoint): If stopped by trace, set the LWP's
stop reason to TARGET_STOPPED_BY_SINGLE_STEP.
(linux_detach): Complete an ongoing step-over.
(lwp_suspended_inc, lwp_suspended_decr): New functions. Use
throughout.
(resume_stopped_resumed_lwps): Don't resume a suspended thread.
(linux_wait_1): If passing a signal to the inferior after
finishing a step-over, unsuspend and re-resume all lwps. If we
see a single-step event but the thread should be continuing, don't
pass the trap to gdb.
(stuck_in_jump_pad_callback, move_out_of_jump_pad_callback): Use
internal_error instead of gdb_assert.
(enqueue_pending_signal): New function.
(check_ptrace_stopped_lwp_gone): Add debug output.
(start_step_over): Use internal_error instead of gdb_assert.
(complete_ongoing_step_over): New function.
(linux_resume_one_thread): Don't resume a suspended thread.
(proceed_one_lwp): If the LWP is stepping over a breakpoint, reset
it stepping.
gdb/testsuite/ChangeLog:
2015-08-06 Pedro Alves <palves@redhat.com>
* gdb.threads/forking-threads-plus-breakpoint.exp: New file.
* gdb.threads/forking-threads-plus-breakpoint.c: New file.
This should be just a move with no changes.
gdb/ChangeLog
2015-07-15 Aleksandar Ristovski <aristovski@qnx.com
Jan Kratochvil <jan.kratochvil@redhat.com>
Move linux_find_memory_regions_full & co.
* linux-tdep.c (nat/linux-maps.h): Include.
(gdb_regex.h): Remove the include.
(enum filterflags, struct smaps_vmflags, read_mapping, decode_vmflags)
(mapping_is_anonymous_p, dump_mapping_p): Moved to nat/linux-maps.c.
(linux_find_memory_region_ftype): Moved typedef to nat/linux-maps.h.
(linux_find_memory_regions_full): Moved definition to nat/linux-maps.c.
* nat/linux-maps.c: Include ctype.h, target/target-utils.h, gdb_regex.h
and target/target.h.
(struct smaps_vmflags, read_mapping, decode_vmflags)
(mapping_is_anonymous_p, dump_mapping_p): Move from linux-tdep.c.
(linux_find_memory_regions_full): Move from linux-tdep.c.
* nat/linux-maps.h (read_mapping): New declaration.
(linux_find_memory_region_ftype, enum filterflags): Moved from
linux-tdep.c.
(linux_find_memory_regions_full): New declaration.
* target.c (target/target-utils.h): Include.
(read_alloc_pread_ftype): Moved typedef to target/target-utils.h.
(read_alloc, read_stralloc_func_ftype, read_stralloc): Moved
definitions to target/target-utils.c.
* target.h (target_fileio_read_stralloc): Move it to target/target.h.
* target/target-utils.c (read_alloc, read_stralloc): Move definitions
from target.c.
* target/target-utils.h (read_alloc_pread_ftype): New typedef.
(read_alloc): New declaration.
(read_stralloc_func_ftype): New typedef.
(read_stralloc): New declaration.
* target/target.h (target_fileio_read_stralloc): Move it from target.h.
gdb/gdbserver/ChangeLog
2015-07-15 Aleksandar Ristovski <aristovski@qnx.com
Jan Kratochvil <jan.kratochvil@redhat.com>
* target.c: Include target/target-utils.h and fcntl.h.
(target_fileio_read_stralloc_1_pread, target_fileio_read_stralloc_1)
(target_fileio_read_stralloc): New functions.
stdint.h was added to common-defs.h some months ago and should
no longer be included directly by any file.
gdb_assert.h was added to common-defs.h nearly a year ago, but
three includes have crept in since then.
This commit removes all such redundant include directives.
gdb/ChangeLog:
* common/buffer.c (stdint.h): Do not include.
* common/print-utils.c (stdint.h): Likewise.
* compile/compile-c-symbols.c (gdb_assert.h): Likewise.
* compile/compile-c-types.c (gdb_assert.h): Likewise.
* ft32-tdep.c (gdb_assert.h): Likewise.
* guile/scm-utils.c (stdint.h): Likewise.
* i386-linux-tdep.c (stdint.h): Likewise.
* i386-tdep.c (stdint.h): Likewise.
* nat/linux-btrace.c (stdint.h): Likewise.
* nat/linux-btrace.h (stdint.h): Likewise.
* nat/linux-ptrace.c (stdint.h): Likewise.
* nat/mips-linux-watch.h (stdint.h): Likewise.
* ppc-linux-nat.c (stdint.h): Likewise.
* python/python-internal.h (stdint.h): Likewise.
* stub-termcap.c (stdlib.h): Likewise.
* target/target.h (stdint.h): Likewise.
* xtensa-linux-nat.c (stdint.h): Likewise.
gdb/gdbserver/ChangeLog:
* linux-i386-ipa.c (stdint.h): Do not include.
* lynx-i386-low.c (stdint.h): Likewise.
* lynx-ppc-low.c (stdint.h): Likewise.
* mem-break.c (stdint.h): Likewise.
* thread-db.c (stdint.h): Likewise.
* tracepoint.c (stdint.h): Likewise.
* win32-low.c (stdint.h): Likewise.
This commit renames target_stop_ptid as target_stop_and_wait and
target_continue_ptid as target_continue_no_signal. Comments are
updated to more fully describe the functions' behaviour.
gdb/ChangeLog:
* target/target.h (target_stop_ptid): Renamed as...
(target_stop_and_wait): New function. Updated comment.
All uses updated.
(target_continue_ptid): Renamed as...
(target_continue_no_signal): New function. Updated comment.
All uses updated.
This commit makes 19 of the 22 shared .c files in common, nat and
target include common-defs.h instead of defs.h/server.h. The
remaining three files need slight extra work and are dealt with
in separate commits.
gdb/ChangeLog:
* common/agent.c: Include common-defs.h.
Don't include defs.h or server.h.
* common/buffer.c: Likewise.
* common/common-debug.c: Likewise.
* common/common-utils.c: Likewise.
* common/errors.c: Likewise.
* common/filestuff.c: Likewise.
* common/format.c: Likewise.
* common/gdb_vecs.c: Likewise.
* common/print-utils.c: Likewise.
* common/ptid.c: Likewise.
* common/rsp-low.c: Likewise.
* common/signals.c: Likewise.
* common/vec.c: Likewise.
* common/xml-utils.c: Likewise.
* nat/linux-osdata.c: Likewise.
* nat/linux-procfs.c: Likewise.
* nat/linux-ptrace.c: Likewise.
* nat/mips-linux-watch.c: Likewise.
* target/waitstatus.c: Likewise.
This commit introduces two new functions to stop and restart target
processes that shared code can use and that clients must implement.
It also changes some shared code to use these functions.
gdb/ChangeLog:
* target/target.h (target_stop_ptid, target_continue_ptid):
Declare.
* target.c (target_stop_ptid, target_continue_ptid): New
functions.
* common/agent.c [!GDBSERVER]: Don't include infrun.h.
(agent_run_command): Always use target_stop_ptid and
target_continue_ptid.
gdb/gdbserver/ChangeLog:
* target.c (target_stop_ptid, target_continue_ptid): New
functions.
This introduces target/target.h. This file declares some functions
that the shared code can use and that clients must implement. It also
changes some shared code to use these functions.
gdb/ChangeLog:
* target/target.h: New file.
* Makefile.in (HFILES_NO_SRCDIR): Add target/target.h.
* target.h: Include target/target.h.
(target_read_memory, target_write_memory): Don't declare.
* target.c (target_read_uint32): New function.
* common/agent.c: Include target/target.h.
[!GDBSERVER]: Don't include target.h.
(helper_thread_id): Type changed to uint32_t.
(agent_get_helper_thread_id): Use target_read_uint32.
(agent_run_command): Always use target_read_memory and
target_write_memory.
(agent_capability): Type changed to uint32_t.
(agent_capability_check): Use target_read_uint32.
gdb/gdbserver/ChangeLog:
* target.h: Include target/target.h.
* target.c (target_read_memory, target_read_uint32)
(target_write_memory): New functions.
This commit moves the inclusion of common-utils.h to common-defs.h and
removes all other inclusions.
gdb/
2014-08-07 Gary Benson <gbenson@redhat.com>
* common/common-defs.h: Include common-utils.h.
* defs.h: Do not include common-utils.h.
* common/gdb_assert.h: Likewise.
* darwin-nat.h: Likewise.
* nat/linux-btrace.c: Likewise.
* target/waitstatus.h: Likewise.
gdb/gdbserver/
2014-08-07 Gary Benson <gbenson@redhat.com>
* server.h: Do not include common-utils.h.
This commit moves the inclusion of ptid.h to common-defs.h and removes
all other inclusions.
gdb/
2014-08-07 Gary Benson <gbenson@redhat.com>
* common/common-defs.h: Include ptid.h.
* defs.h: Do not include ptid.h.
* inferior.h: Likewise.
* infrun.h: Likewise.
* nat/linux-btrace.h: Likewise.
* nat/linux-osdata.h: Likewise.
* target/waitstatus.h: Likewise.
gdb/gdbserver/
2014-08-07 Gary Benson <gbenson@redhat.com>
* server.h: Do not include ptid.h.
* notif.h: Likewise.
The other day while debugging something related to random signals, I
got confused with "set debug infrun 1" output, for it said:
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x323d4e8b94
infrun: random signal 20
On GNU/Linux, 20 is SIGTSTP. For some reason, it took me a few
minutes to realize that 20 is actually a GDB signal number, not a
target signal number (duh!). In any case, I propose making GDB's
output clearer here:
One way would be to use gdb_signal_to_name, like already used
elsewhere:
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x323d4e8b94
infrun: random signal SIGCHLD (20)
but I think that might confuse someone too ("20? Why does GDB believe
SIGCHLD is 20?"). So I thought of printing the enum string instead:
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x323d4e8b94
infrun: random signal GDB_SIGNAL_CHLD (20)
Looking at a more complete infrun debug log, we had actually printed
the (POSIX) signal name name a bit before:
infrun: target_wait (-1, status) =
infrun: 9300 [Thread 0x7ffff7fcb740 (LWP 9300)],
infrun: status->kind = stopped, signal = SIGCHLD
...
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x323d4e8b94
infrun: random signal 20
So I'm now thinking that it'd be even better to make infrun output
consistently use the enum symbol string, like so:
infrun: clear_proceed_status_thread (Thread 0x7ffff7fca700 (LWP 25663))
infrun: clear_proceed_status_thread (Thread 0x7ffff7fcb740 (LWP 25659))
- infrun: proceed (addr=0xffffffffffffffff, signal=144, step=1)
+ infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT, step=1)
- infrun: resume (step=1, signal=0), trap_expected=0, current thread [Thread 0x7ffff7fcb740 (LWP 25659)] at 0x400700
+ infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current thread [Thread 0x7ffff7fcb740 (LWP 25659)] at 0x400700
infrun: wait_for_inferior ()
infrun: target_wait (-1, status) =
infrun: 25659 [Thread 0x7ffff7fcb740 (LWP 25659)],
- infrun: status->kind = stopped, signal = SIGCHLD
+ infrun: status->kind = stopped, signal = GDB_SIGNAL_CHLD
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x400700
- infrun: random signal 20
+ infrun: random signal (GDB_SIGNAL_CHLD)
infrun: random signal, keep going
- infrun: resume (step=1, signal=20), trap_expected=0, current thread [Thread 0x7ffff7fcb740 (LWP 25659)] at 0x400700
+ infrun: resume (step=1, signal=GDB_SIGNAL_CHLD), trap_expected=0, current thread [Thread 0x7ffff7fcb740 (LWP 25659)] at 0x400700
infrun: prepare_to_wait
infrun: target_wait (-1, status) =
infrun: 25659 [Thread 0x7ffff7fcb740 (LWP 25659)],
- infrun: status->kind = stopped, signal = SIGTRAP
+ infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_STOPPED
infrun: stop_pc = 0x400704
infrun: stepi/nexti
infrun: stop_stepping
GDB's signal numbers are public and hardcoded (see
include/gdb/signals.h), so there's really no need to clutter the
output with numeric values in some places while others not. Replacing
the magic "144" with GDB_SIGNAL_DEFAULT in "proceed"'s debug output
(see above) I think is quite nice.
I posit that all this makes it clearer to newcomers that GDB has its
own signal numbering (and that there must be some mapping going on).
Tested on x86_64 Fedora 17.
gdb/
2013-10-23 Pedro Alves <palves@redhat.com>
* common/gdb_signals.h (gdb_signal_to_symbol_string): Declare.
* common/signals.c: Include "gdb_assert.h".
(signals): New field 'symbol'.
(SET): Use the 'symbol' parameter.
(gdb_signal_to_symbol_string): New function.
* infrun.c (handle_inferior_event) <random signal>: In debug
output, print the random signal enum as string in addition to its
number.
* target/waitstatus.c (target_waitstatus_to_string): Print the
signal's enum value as string instead of the (POSIX) signal name.
Pedro Alves