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431 commits

Author SHA1 Message Date
Tom de Vries
6c98b8bce9 [gdb] Drop nullptr in "get_selected_frame (nullptr)"
I came across "get_selected_frame (nullptr)", and realized nullptr is the
default argument, so this can be simplified to "get_selected_frame ()".

Do so using the following script:
...
$ find gdb* -type f -name "*.[ch]" -o -name "*.cc" \
    | xargs sed -i 's/get_selected_frame (nullptr)/get_selected_frame ()/'
...
and likewise for "get_selected_frame (NULL)".

Tested on x86_64-linux.

Approved-By: Tom Tromey <tom@tromey.com>
2026-06-05 23:06:48 +02:00
Markus Metzger
f1fdd3164b gdb: use all_threads() in for_each_thread()
In for_each_thread(), we use all_threads_safe(), which allows deleting the
thread.  This it not needed in the cases where it is currently used and it
causes the iterator to get corrupted when threads are deleted in a nested
all_threads_safe() iteration.

One such scenario is as follows:
- remote debugging in non-stop mode
- one thread has hit a breakpoint
- one thread exited but GDB does not know about it, yet
- resume with 'continue -a'
- the continue command uses for_each_thread() to proceed threads individually
- the stopped thread starts an inline step-over (displaced stepping disabled)
- update_thread_list() learns about the exit and deletes the thread
- the safe iterator's m_next still points to the deleted thread

Approved-By: Tom Tromey <tom@tromey.com>
2026-05-15 05:10:47 +00:00
Markus Metzger
aca091c462 gdb: use correct target in notify_thread_exited()
clean_up_just_stopped_threads_fsms() may call notify_thread_exited() in
the context of a thread from a different target.

Switch to the thread's inferior to get the target right.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2026-05-11 07:00:19 +00:00
Andrew Burgess
430f15b5be gdb: notify of inferior switch when needed from 'thread' command
While working on the commit:

  commit 9959019545d8d6d71d927f20f088efba944b1e9c
  Date:   Sun Sep 28 16:16:53 2025 +0100

      gdb: fix for 'set suppress-cli-notifications on' missed case

I spotted this message in the gdb.mi/user-selected-context-sync.exp
test script:

  # Idea for the future: selecting a thread in a different inferior.  For now,
  # GDB doesn't show an inferior switch, but if it did, it would be a nice
  # place to test it.

What this message is talking about is this behaviour:

  (gdb) info threads
    Id   Target Id                              Frame
    1.1  Thread 0xf7dbc700 (LWP 818430) "thr" 0xf7eb2888 in clone () from /lib/libc.so.6
    1.2  Thread 0xf7dbbb40 (LWP 818433) "thr" 0xf7fd0579 in __kernel_vsyscall ()
    1.3  Thread 0xf73ffb40 (LWP 818434) "thr" breakpt () at thr.c:19
    2.1  Thread 0xf7dbc700 (LWP 818456) "thr" 0xf7eb2888 in clone () from /lib/libc.so.6
    2.2  Thread 0xf7dbbb40 (LWP 818457) "thr" breakpt () at thr.c:19
  * 2.3  Thread 0xf73ffb40 (LWP 818458) "thr" breakpt () at thr.c:19
  (gdb) inferior 1
  [Switching to inferior 1 [process 818430] (/home/andrew/tmp/thr)]
  [Switching to thread 1.1 (Thread 0xf7dbc700 (LWP 818430))]
  #0  0xf7eb2888 in clone () from /lib/libc.so.6
  (gdb) thread 2.2
  [Switching to thread 2.2 (Thread 0xf7dbbb40 (LWP 818457))]
  #0  breakpt () at thr.c:19
  19	  while (stop)
  (gdb)

Notice that when we switch from thread 2.3 to 1.1 using the 'inferior
1' command, GDB tells us that the inferior has changed, and that the
thread has changed (and also that the frame has changed).

But, when we switch from 1.1 to 2.2 using the 'thread 2.2' command, we
are only told about the thread change.

The 'Switching to inferior ...' line includes some useful information,
the process PID and the executable name, and I think it is a shame
that these are not presented when using the 'thread' command to switch
inferior.

So, this commit addresses this issue.

A question that came up during review, and which I'm clarifying here:
this change only affects the output of GDB when the thread command is
also used to switch inferiors.  I am (in effect) arguing that the
command 'thread 2.2' should be treated as a shorthand for 'inferior 2;
thread 2', and should display all of the associated output.  If the
user is only switching threads within a single inferior then it is not
necessary to re-display the inferior information.

I acknowledge that this does mean the output of the 'thread' command
will now be different depending on whether the user changes inferior
or not.  However, I think this is better than the alternative, having
the 'thread' command always re-print the inferior information.  I
think this would introduce excess noise that is not useful.

There are changes in basically two areas.  The easy part is in
thread_command (thread.c).  Here we spot when the inferior has changed
as a result of the 'thread' command, and include
USER_SELECTED_INFERIOR in the set of state passed to the
notify_user_selected_context_changed function.

The change in mi/mi-main.c is a little more involved.  In the
mi_cmd_execute function we use an instance of user_selected_context to
spot if any inferior state (frame, thread, or inferior) changes after
an MI command, this is then used to decide if there should be a call
to interps_notify_user_selected_context_changed.

First, by calling interps_notify_user_selected_context_changed
directly, instead of notify_user_selected_context_changed, we fail to
trigger the Python selected_context event, which feels like a
mistake.  If the context is changed via an MI command, I think we
should still trigger the Python event.  So the first thing I did was
change the interps_notify_user_selected_context_changed call into a
call to notify_user_selected_context_changed.  I updated the
gdb.python/py-selected-context.exp test to cover this case.

After that, in mi_cmd_execute, notify_user_selected_context_changed is
always passed 'USER_SELECTED_THREAD | USER_SELECTED_FRAME'.  This
makes sense, the MI doesn't allow "switching inferiors" as a command,
instead, an MI frontend must switch threads, and the inferior is
switched as a consequence.  But this does mean that if a user has a
CLI and MI interpreter running, and the MI switches threads, the CLI
will only receive the thread switch style notifications, that is,
there will be no "Switching to inferior ..." line.

What I've done is rename user_selected_context::has_changed to
user_selected_context::what_changed, this function is now responsible
for returning the set of USER_SELECTED_* flags that indicate what
changed.

If anything has changed then we always return USER_SELECTED_THREAD |
USER_SELECTED_FRAME as a minimum.  This retains the existing
behaviour, but is possibly more aggressive than we need to be; the
-stack-select-frame command can only change the frame, so maybe in
this case we should only return USER_SELECTED_FRAME?  I've left that
for the future though.

However, the important change is that in ::what_changed, I now spot
when the inferior has changed and include USER_SELECTED_INFERIOR in
the set of flags that are returned.

In mi_cmd_execute we now call the new what_changed function, and use
the set of flags returned when calling
notify_user_selected_context_changed.  This means that the CLI will
now receive inferior changed notifications when appropriate.

The gdb.mi/user-selected-context-sync.exp script has been updated,
replacing the comment I quoted above with an actual test that the
inferior change is announced correctly.

Reviewed-By: Guinevere Larsen <guinevere@redhat.com>
Reviewed-By: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
2026-05-04 21:30:36 +01:00
Tankut Baris Aktemur
9de228e0cb gdb, multi-target: pass a target argument to delete_exited_threads
Similar to the parent commit, delete_exited_threads is also mostly
used in the context of a particular target.  Pass that target as a
parameter and skip other targets.

There seems to be two cases where we actually would want to iterate
all targets.  One use is in inferior_appeared (inferior.c) and the
other is in thread_select (thread.c).  To handle these cases, allow
the argument to be nullptr.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2026-04-21 09:11:02 +02:00
Tankut Baris Aktemur
076b132589 gdb, multi-target: pass a target argument to prune_threads
The 'prune_threads' function is used by various targets; in one case
in the 'create_inferior' method, in all other cases in
'update_thread_list'.  This is an indication that the function should
handle the threads that belong to the calling target and not mess with
the threads of other targets.  So, while iterating the threads, ignore
those that do not belong to the current target.  To do this,
prune_threads is modified to take a process_stratum_target as a
parameter.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2026-04-21 09:11:02 +02:00
Simon Marchi
cfe0642a7f gdb: split iterate_over_threads into for_each_thread and find_thread
Same rationale as the previous patch, I think the code would be clearer
and simpler with separate "for each" and "find" functions rather than
one that does both jobs.

No need for the callbacks of the "for each" function to return anything,
as none of them needs to interrupt the iteration.

Change-Id: I4b7bcc5e9a319369d75a22b11114e943951e546a
Approved-By: Andrew Burgess <aburgess@redhat.com>
2026-04-17 15:30:30 -04:00
Pedro Alves
2954dd2b73 thread_info::executing+resumed -> thread_info::internal_state
While working on Windows non-stop support, I ran into a
very-hard-to-track-down bug.

The problem turned out to be that
infrun.c:proceed_resume_thread_checked resumed an already-executing
thread because the thread was marked as "executing=true,
resumed=false", and that function only skips resuming threads that are
marked resumed=true.  The consequence was that GDB corrupted the
registers of the Windows DLL loader threads, eventually leading to a
GDB+inferior deadlock.

Originally, the "resumed" flag was only ever set when infrun decided
is was ready to process a thread's pending wait status.  infrun has
since evolved to set the resumed flag when we set a thread's executing
flag too.  We are not always consistent throughout in guaranteeing
that a thread is marked resumed=true whenever it is marked
executing=true, though.  For instance, no target code that supports
non-stop mode (linux-nat, remote, and windows-nat with this series) is
making sure that new threads are marked resumed=true when they are
added to the thread list.  They are only marked as {state=running,
executing=true}, the "resumed" flag is not touched.

Making proceed_resume_thread_checked check thr->executing() in
addition to thr->resumed(), feels like papering over a combination of
states that shouldn't happen nowadays.

OTOH, having to have the target backends mark new threads as
resumed=true just feels like too many different states (three) to set:

  add_thread (...);
  set_running (...);
  set_executing (...);
  set_resumed (...);

Yuck.  I think we can do better.

We really have too many "state tracking" flags in a thread.
Basically:

 - whether a thread is "running/stopped/exited" (from the user's
   perspective).  This is the thread_info::state field.

 - whether a thread is "executing" (infrun asked the target to set the
   thread executing).  This is thread_info::executing().

 - whether a thread is "resumed" (infrun wants the thread to be
   resumed, but maybe can't yet because the thread has a pending wait
   status).  This is thread_info::resumed()

"running", "executing", and "resumed" are almost synonyms, so this can
be highly confusing English-wise too.

For "running" vs "executing", in comments, we tipically need to
explain that "running/stopped/exited" is for the user/frontend
perspective, while "executing true/false" is for gdb's internal run
control.

(Also, "executing or not" can also mean something else in GDB's
codebase -- "target has execution" does not mean that threads are
actually running right now -- it's a test for whether we have a live
process vs a core dump!)

One simplification we can do that avoids this running vs executing
ambiguity is to replace the "executing" field with an "internal_state"
field, similar to the thread_info::state field, and make that new
internal_state field reuse the same enum thread_state type that is
used by thread_info::state.  Like:

  struct thread_info
  {
  ...
    /* Frontend/public/external/user view of the thread state.  */
    enum thread_state m_state = THREAD_STOPPED;

    /* The thread's internal state.  When the thread is stopped
       internally while handling an internal event, like a software
       single-step breakpoint, the internal state will be
       THREAD_STOPPED, but the external state will still be
       THREAD_RUNNING.  */
    enum thread_state m_internal_state = THREAD_STOPPED;
  };

(Assume we'd add state() and internal_state() getters.)

With that, every check for thr->executing() is replaced with a
'thr->internal_state() == THREAD_RUNNING' check, and the code is
clearer by design.  There is no confusion between "running" vs
"executing" any more, because they now mean the exact same thing.
Instead, we say e.g., 'thread has (user) state "running", and internal
state "stopped"'.  Or simpler, 'thread is running (from the user's
perspective), but internally stopped'.  That is after all what we
would way in comments today already.

That still leaves the 'resumed' flag, though.  That's the least
obvious one.  Turns out we can get rid of it, and make it a new state
tracked by thread_info::internal_state.  That is, we make
internal_state have its own enumeration type (decoupled from
thread_info::state's type), and convert the resumed true/false flag to
a new enumerator of this new enumeration.  Like so:

  enum thread_int_state
  {
    THREAD_INT_STOPPED,
    THREAD_INT_RUNNING,
 +   THREAD_INT_RESUMED_PENDING_STATUS,
    THREAD_INT_EXITED,
  };

That is what this patch does.  So in summary, we go from:

 thread_info::state {THREAD_STOPPED, THREAD_RUNNING, THREAD_EXITED}
 thread_info::executing {false, true}
 thread_info::resumed {false, true}

to:

 thread_info::state {THREAD_STOPPED, THREAD_RUNNING, THREAD_EXITED}
 thread_info::internal_state {THREAD_INT_STOPPED, THREAD_INT_RUNNING,
                              THREAD_INT_RESUMED_PENDING_STATUS,
			      THREAD_INT_EXITED}

The patch adds getters/setters for both (user) state and
internal_state, and adds assertions around state transitions, ensuring
that internal_state doesn't get out of sync with
thread::have_pending_wait_status().

The code that adds/removes threads from the proc_target's
resumed_with_pending_wait_status list is all centralized within
thread_info::set_internal_state, when we switch to/from the
resumed-pending-status state.  With the assertions in place, it should
be impossible to end up with a THREAD_INT_RUNNING thread with a
pending status.

The thread.c:set_running, thread.c:set_executing, thread.c:set_resumed
global functions are all gone, replaced with new thread.c:set_state
and thread.c:set_internal_state functions.

Tested on x86_64-linux-gnu, native and gdbserver.

Change-Id: I4f5097d68f4694d44e1ae23fea3e9bce45fb078c
commit-id:42ba97d4
2026-04-06 18:50:19 +01:00
Tom Tromey
29d91b3c90 Move buffered stream to new files
The buffered stream code is currently in ui-out.h and ui-out.c, which
seems weird because it seems more like a low-level ui-file idea (for
the most part, it does also affect some ui_out).

This patch moves the declarations to a new header file,
buffered-streams.h and the implementation to buffered-streams.c.  This
seems cleaner to me.

Approved-By: Andrew Burgess <aburgess@redhat.com>
2026-02-09 08:09:09 -07:00
Tom Tromey
f99be06dbd Mention gdb thread ID in thread messages
Currently the "new thread" message that gdb might print does not
include gdb's own thread ID -- so, if you want to reference the
thread, you must first use "thread find" or "info threads".

This patch changes the announcement to mention the thread.  The
thread-exit message is also updated.

I chose to have it display like this:

    [New Thread 0x7ffff7cbe6c0 (LWP 1267702) (id 2)]
    [Thread 0x7ffff6cbd6c0 (LWP 1267703) (id 3) exited]

... with the 'id' coming later, because it's somewhat of a pain to
wedge the thread id just after the "thread" string where (IMO) it
would more naturally belong.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=19584
2026-01-07 11:33:05 -07:00
Tom Tromey
e3bcc054af Make 'print_thread_events' static
This makes the 'print_thread_events' global static.  It's never used
outside of thread.c.

Reviewed-by: Stephan Rohr <stephan.rohr@intel.com>
2026-01-07 11:33:04 -07:00
Tom Tromey
4abc1ce2cc Update copyright dates to include 2026
This updates the copyright headers to include 2026.  I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
2026-01-05 13:16:46 -07:00
Andrew Burgess
bfea7d3059 gdb: fix for 'set suppress-cli-notifications on' missed case
I noticed this behaviour:

  (gdb) info threads
    Id   Target Id                               Frame
    1    Thread 0xf7dbc700 (LWP 3161872) "thr" 0xf7eb2888 in clone () from /lib/libc.so.6
  * 2    Thread 0xf7dbbb40 (LWP 3161884) "thr" breakpt () at thr.c:19
  (gdb) set suppress-cli-notifications on
  (gdb) thread 1
  (gdb) thread 1
  [Switching to thread 1 (Thread 0xf7dbc700 (LWP 3161872))]
  #0  0xf7eb2888 in clone () from /lib/libc.so.6
  (gdb)

I think that the second 'thread 1' should not produce any output just
like the 'inferior' command, continuing in the same GDB session:

  (gdb) inferior 1
  (gdb)

Without suppress-cli-notifications we would see an inferior, thread,
and frame being printed, but with suppress-cli-notifications set to
on, we get no output.

The difference in behaviours is that in inferior_command (inferior.c),
we always call notify_user_selected_context_changed, even in the case
where the inferior doesn't actually change.

In thread_command (thread.c), we have some code that catches the
thread not changed case, and calls print_selected_thread_frame.  The
notify_user_selected_context_changed function is only called if the
thread actually changes.

I did consider simply extending thread_command to check the global
cli_suppress_notification.user_selected_context state and skipping the
call to print_selected_thread_frame if suppression is on.

However, I realised that calling print_selected_thread_frame actually
introduces a bug.

When the 'thread' command is used to select the currently selected
thread, GDB still calls 'thread_selected'.  And 'thread_select' always
selects frame #0 within that thread, consider this session:

  (gdb) info threads
    Id   Target Id                              Frame
    1    Thread 0xf7dbc700 (LWP 723986) "thr" 0xf7eb2888 in clone () from /lib/libc.so.6
  * 2    Thread 0xf7dbbb40 (LWP 723990) "thr" breakpt () at thr.c:19
  (gdb) bt
  #0  breakpt () at thr.c:19
  #1  0x080491fd in thread_worker (arg=0xffff9514) at thr.c:31
  #2  0xf7f7667e in start_thread () from /lib/libpthread.so.0
  #3  0xf7eb289a in clone () from /lib/libc.so.6
  (gdb) frame 3
  #3  0xf7eb289a in clone () from /lib/libc.so.6
  (gdb) thread 2
  [Switching to thread 2 (Thread 0xf7dbbb40 (LWP 723990))]
  #0  breakpt () at thr.c:19
  19	  while (stop)
  (gdb) frame
  #0  breakpt () at thr.c:19
  19	  while (stop)
  (gdb)

Notice that the frame resets back to frame #0.

By only calling print_selected_thread_frame, and not calling
notify_user_selected_context_changed, this means that GDB will fail to
emit an MI async notification.  It is this async notification which
tells MI consumers that the frame has been reset to #0.

And so, I think that the correct solution is, like with the 'inferior'
command, to always call notify_user_selected_context_changed.

This does mean that in some cases unnecessary MI notifications can be
emitted, however, an MI consumer should be able to handle these.  We
could try to avoid these, but we would need to extend thread_command
to check that neither the thread OR frame has changed after the call
to thread_select, and right now, I'm not sure it's worth adding the
extra complexity.

I've rewritten the gdb.base/cli-suppress-notification.exp test to
cover more cases, especially the reselecting the same thread case.
And I've updated the gdb.mi/user-selected-context-sync.exp test to
allow for the additional MI notifications that are emitted, and to
check the frame reset case.

While working on this change, I did wonder about calls to
notify_user_selected_context_changed for frame related commands.  In
places we do elide calls to notify_user_selected_context_changed if
the frame hasn't changed.  I wondered if there were more bugs here?

I don't think there are though.  While changing the inferior will also
change the selected thread, and the selected frame.  And changing the
thread will also change the selected frame.  Changing the frame is the
"inner most" context related thing that can be changed.  There are no
side effect changes that also need to be notified, so for these cases,
I think we are fine.

Also in infrun.c I fixed a code style issue relating to
notify_user_selected_context_changed.  It's not a functional change
required by this commit, but it's related to this patch, so I'm
including it here.

Reviewed-By: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Tested-By: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Approved-By: Tom Tromey <tom@tromey.com>
2025-10-08 09:25:50 +01:00
Simon Marchi
675a17a8a5 gdb: change all_threads_safe to yield references
To be consistent with all_threads and the others, following the previous
patch.

Change-Id: I4ee4ff32b005fc5554a9d637725f10fca70cee14
Approved-By: Tom Tromey <tom@tromey.com>
2025-10-07 16:22:15 -04:00
Simon Marchi
1ad8737b3c gdb: change inf_threads_iterator to yield references
When adding reference_to_pointer_iterator, I saw it as a temporary
thing, to not have to do a codebase-wide change right away.  Remove it
from inf_threads_iterator and adjust all the users.

It's very possible that I forgot to update some spots in the files I
can't compile, but it will be very easy to fix if that happens.

Change-Id: Iddc462fecfaafb6a9861d185b217bc714e7dc651
Approved-By: Tom Tromey <tom@tromey.com>
2025-10-07 16:22:15 -04:00
Tom Tromey
3719472095 Use gnulib c-ctype module in gdb
PR ada/33217 points out that gdb incorrectly calls the <ctype.h>
functions.  In particular, gdb feels free to pass a 'char' like:

    char *str = ...;
    ... isdigit (*str)

This is incorrect as isdigit only accepts EOF and values that can be
represented as 'unsigned char' -- that is, a cast is needed here to
avoid undefined behavior when 'char' is signed and a character in the
string might be sign-extended.  (As an aside, I think this API seems
obviously bad, but unfortunately this is what the standard says, and
some systems check this.)

Rather than adding casts everywhere, this changes all the code in gdb
that uses any <ctype.h> API to instead call the corresponding c-ctype
function.

Now, c-ctype has some limitations compared to <ctype.h>.  It works as
if the C locale is in effect, so in theory some non-ASCII characters
may be misclassified.  This would only affect a subset of character
sets, though, and in most places I think ASCII is sufficient -- for
example the many places in gdb that check for whitespace.
Furthermore, in practice most users are using UTF-8-based locales,
where these functions aren't really informative for non-ASCII
characters anyway; see the existing workarounds in gdb/c-support.h.

Note that safe-ctype.h cannot be used because it causes conflicts with
readline.h.  And, we canot poison the <ctype.h> identifiers as this
provokes errors from some libstdc++ headers.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33217
Approved-By: Simon Marchi <simon.marchi@efficios.com>
2025-09-09 11:59:04 -06:00
Tom Tromey
5fe70629ce Change file initialization to use INIT_GDB_FILE macro
This patch introduces a new macro, INIT_GDB_FILE.  This is used to
replace the current "_initialize_" idiom when introducing a per-file
initialization function.  That is, rather than write:

    void _initialize_something ();
    void
    _initialize_something ()
    {
       ...
    }

... now you would write:

    INIT_GDB_FILE (something)
    {
       ...
    }

The macro handles both the declaration and definition of the function.

The point of this approach is that it makes it harder to accidentally
cause an initializer to be omitted; see commit 2711e475 ("Ensure
cooked_index_entry self-tests are run").  Specifically, the regexp now
used by make-init-c seems harder to trick.

New in v2: un-did some erroneous changes made by the script.

The bulk of this patch was written by script.
Regression tested on x86-64 Fedora 41.
2025-06-26 06:15:59 -06:00
Tankut Baris Aktemur
be437614a1 gdb: add '-stopped' and '-running' options to "info threads"
Add two options to "info threads": `-stopped` and `-running`.

The purpose of these options is to filter the output of the command.
The `-stopped` option means "print stopped threads only" and,
similarly, `-running` means "print the running threads only".  When
both options are provided by the user, the indication is that the user
wants the union.  That is, the output contains both stopped and
running threads.

Suppose we have an application with 5 threads, 2 of which have hit a
breakpoint.  The "info threads" command in the non-stop mode gives:

  (gdb) info threads
    Id   Target Id             Frame
  * 1    Thread 0x7ffff7d99740 (running)
    2    Thread 0x7ffff7d98700 something () at file.c:30
    3    Thread 0x7ffff7597700 (running)
    4    Thread 0x7ffff6d96700 something () at file.c:30
    5    Thread 0x7ffff6595700 (running)
  (gdb)

Using the "-stopped" flag, we get

  (gdb) info threads -stopped
    Id   Target Id             Frame
    2    Thread 0x7ffff7d98700 something () at file.c:30
    4    Thread 0x7ffff6d96700 something () at file.c:30
  (gdb)

Using the "-running" flag, we get

  (gdb) info threads -running
    Id   Target Id             Frame
  * 1    Thread 0x7ffff7d99740 (running)
    3    Thread 0x7ffff7597700 (running)
    5    Thread 0x7ffff6595700 (running)
  (gdb)

Using both flags prints all:

  (gdb) info threads -stopped -running
    Id   Target Id             Frame
  * 1    Thread 0x7ffff7d99740 (running)
    2    Thread 0x7ffff7d98700 something () at file.c:30
    3    Thread 0x7ffff7597700 (running)
    4    Thread 0x7ffff6d96700 something () at file.c:30
    5    Thread 0x7ffff6595700 (running)
  (gdb)

When combined with a thread ID, filtering applies to those threads that
are matched by the ID.

  (gdb) info threads 3
    Id   Target Id             Frame
    3    Thread 0x7ffff7597700 (running)
  (gdb) info threads -stopped 3
  No threads matched.
  (gdb)

Regression-tested on X86_64 Linux.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Reviewed-By: Guinevere Larsen <guinevere@redhat.com>
Approved-by: Pedro Alves <pedro@palves.net
2025-05-12 09:11:25 +02:00
Tankut Baris Aktemur
0ea1e5df96 gdb: update "info threads" output when no threads match the arguments
If "info threads" is provided with the thread ID argument but no such
threads matching the thread ID(s) are found, GDB prints

  No threads match '<ID...>'.

Update this output to the more generalized

  No threads matched.

The intention is that the next patch, and potentially future ones,
will extend the command with more filter/match arguments.  We cannot
customize the output to each such argument.  Hence, be more generic.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-by: Pedro Alves <pedro@palves.net
2025-05-12 09:11:19 +02:00
Tankut Baris Aktemur
32c39bab07 gdb: pass info_threads_opts to print_thread_info_1
The "info threads" command tracks its options in a struct named
'info_threads_opts', which currently has only one option.  Pass the
whole options object to helper functions, instead of passing
the option value individually.  This is a refactoring to make adding
more options easier.

Reviewed-By: Guinevere Larsen <guinevere@redhat.com>
Approved-by: Pedro Alves <pedro@palves.net
2025-05-12 09:11:10 +02:00
Tom Tromey
d01e823438 Update copyright dates to include 2025
This updates the copyright headers to include 2025.  I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.

Approved-By: Eli Zaretskii <eliz@gnu.org>
2025-04-08 10:54:39 -06:00
Tom Tromey
58984e4ad2 Use gdb::function_view in iterate_over_threads
This C++-ifies iterate_over_threads, changing it to accept a
gdb::function_view and to return bool.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2025-03-11 08:39:58 -06:00
Guinevere Larsen
2f46cda83b gdb: Allow replayed threads to read and write pseudo registers
In an effort to support AVX instructions when recording, we need to
allow replaying threads to access pseudo registers. Currently, if
we try to do that gdb will fail in a call to validate_registers_access,
because the thread is executing so GDB thinks it is unsafe to read
pseudo registers.

When replaying, the thread is really executing for all intents and
purposes, but the execution is just having GDB change values on
registers, so it will always be safe to read and write pseudo registers.
This commit changes functions that check for register access to allow
access when we are replaying. The check to whether we are replaying must
not happen when writing a core file, as record_full_list could be nullptr,
so we only check it if the thread is executing.

As of this commit, I don't know of a way to trigger this commit without
AVX support on record, so a test isn't provided. However, as soon as
record-full supports saving ymm registers, the AVX tests will test this
as well.

Approved-By: Tom Tromey <tom@tromey.com>
2024-10-28 10:46:33 -03:00
Simon Marchi
5b9707eb87 gdb: remove gdbcmd.h
Most files including gdbcmd.h currently rely on it to access things
actually declared in cli/cli-cmds.h (setlist, showlist, etc).  To make
things easy, replace all includes of gdbcmd.h with includes of
cli/cli-cmds.h.  This might lead to some unused includes of
cli/cli-cmds.h, but it's harmless, and much faster than going through
the 170 or so files by hand.

Change-Id: I11f884d4d616c12c05f395c98bbc2892950fb00f
Approved-By: Tom Tromey <tom@tromey.com>
2024-04-25 12:59:02 -04:00
Simon Marchi
824dd26e97 gdb: move execute function declarations from gdbcmd.h to top.h
These functions are implemented in top.c, move their declarations to
top.h.

Change-Id: I8893ef91d955156a6530734fefe8002d78c3e5fc
Approved-By: Tom Tromey <tom@tromey.com>
2024-04-25 12:58:49 -04:00
Simon Marchi
18d2988e5d gdb, gdbserver, gdbsupport: remove includes of early headers
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them.  Remove all the inclusions of these files I could find.  Update
the generation scripts where relevant.

Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26 21:13:22 -04:00
Aaron Merey
519d634396 gdb: Buffer output streams during events that might download debuginfo
Introduce new ui_file buffering_file to temporarily collect output
written to gdb_std* output streams during print_thread, print_frame_info
and print_stop_event.

This ensures that output during these functions is not interrupted
by debuginfod progress messages.

With the addition of deferred debuginfo downloading it is possible
for download progress messages to print during these events.
Without any intervention we can end up with poorly formatted output:

    (gdb) backtrace
    [...]
    #8  0x00007fbe8af7d7cf in pygi_invoke_c_callable (Downloading separate debug info for /lib64/libpython3.11.so.1.0
    function_cache=0x561221b224d0, state=<optimized out>...

To fix this we buffer writes to gdb_std* output streams while allowing
debuginfod progress messages to skip the buffers and print to the
underlying output streams immediately.  Buffered output is then written
to the output streams.  This ensures that progress messages print first,
followed by uninterrupted frame/thread/stop info:

    (gdb) backtrace
    [...]
    Downloading separate debug info for /lib64/libpython3.11.so.1.0
    #8  0x00007fbe8af7d7cf in pygi_invoke_c_callable (function_cache=0x561221b224d0, state=<optimized out>...

Co-Authored-By: Andrew Burgess <aburgess@redhat.com>
Approved-By: Andrew Burgess <aburgess@redhat.com>
2024-01-19 00:18:00 -05:00
Andrew Burgess
1d506c26d9 Update copyright year range in header of all files managed by GDB
This commit is the result of the following actions:

  - Running gdb/copyright.py to update all of the copyright headers to
    include 2024,

  - Manually updating a few files the copyright.py script told me to
    update, these files had copyright headers embedded within the
    file,

  - Regenerating gdbsupport/Makefile.in to refresh it's copyright
    date,

  - Using grep to find other files that still mentioned 2023.  If
    these files were updated last year from 2022 to 2023 then I've
    updated them this year to 2024.

I'm sure I've probably missed some dates.  Feel free to fix them up as
you spot them.
2024-01-12 15:49:57 +00:00
Tom Tromey
0a008773c5 Lazy language setting
When gdb starts up with a symbol file, it uses the program's "main" to
decide the "static context" and the initial language.  With background
DWARF reading, this means that gdb has to wait for a significant
amount of DWARF to be read synchronously.

This patch introduces lazy language setting.  The idea here is that in
many cases, the prompt can show up early, making gdb feel more
responsive.
2024-01-08 18:40:22 -07:00
Pedro Alves
7d1fd67135 Fix thread target ID of exited waves
Currently, if you step over kernel exit, you see:

 stepi
 [AMDGPU Wave ?:?:?:1 (?,?,?)/? exited]
 Command aborted, thread exited.
 (gdb)

Those '?' are because the thread/wave is already gone by the time GDB
prints the "exited" notification, we can't ask dbgapi for any info
about the wave anymore.

This commit fixes it by caching the wave's coordinates as soon as GDB
sees the wave for the first time, and making
amd_dbgapi_target::pid_to_str use the cached info.

At first I thought of clearing the wave_info object from a
thread_exited observer.  However, that is too soon, resulting in this:

 (gdb) si
 [AMDGPU Wave 1:4:1:1 (0,0,0)/0 exited]
 Command aborted, thread exited.
 (gdb) thread
 [Current thread is 6 (AMDGPU Wave ?:?:?:0 (?,?,?)/?) (exited)]

We need instead to clear the wave info when the thread is ultimately
deleted, so we get:

 (gdb) si
 [AMDGPU Wave 1:4:1:1 (0,0,0)/0 exited]
 Command aborted, thread exited.
 (gdb) thread
 [Current thread is 6 (AMDGPU Wave 1:4:1:1 (0,0,0)/0) (exited)]

And for that, we need a new thread_deleted observable.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
Approved-By: Lancelot Six <lancelot.six@amd.com> (amdgpu)
Change-Id: I6c3e22541f051e1205f75eb657b04dc15e547580
2023-12-20 21:20:15 +00:00
Hannes Domani
52e0b52e6f Support dynamically computed convenience variables in get_internalvar_integer
When using $_thread in info threads to showonly the current thread,
you get this error:
```
(gdb) info thread $_thread
Convenience variable must have integer value.
Args must be numbers or '$' variables.
```

It's because $_thread is a dynamically computed convenience
variable, which isn't supported yet by get_internalvar_integer.

Now the output looks like this:
```
(gdb) info threads $_thread
  Id   Target Id           Frame
* 1    Thread 10640.0x2680 main () at C:/src/repos/binutils-gdb.git/gdb/testsuite/gdb.base/gdbvars.c:21
```

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17600
Approved-By: Tom Tromey <tom@tromey.com>
2023-12-12 15:53:12 +01:00
Lancelot Six
6b09f1342c gdb: Replace gdb::optional with std::optional
Since GDB now requires C++17, we don't need the internally maintained
gdb::optional implementation.  This patch does the following replacing:
  - gdb::optional -> std::optional
  - gdb::in_place -> std::in_place
  - #include "gdbsupport/gdb_optional.h" -> #include <optional>

This change has mostly been done automatically.  One exception is
gdbsupport/thread-pool.* which did not use the gdb:: prefix as it
already lives in the gdb namespace.

Change-Id: I19a92fa03e89637bab136c72e34fd351524f65e9
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
2023-11-21 11:52:35 +00:00
Andrew Burgess
96619f154a gdb: move all bfd_cache_close_all calls in gdb_bfd.c
In the following commit I ran into a problem.  The next commit aims to
improve GDB's handling of the main executable being a file on a remote
target (i.e. one with a 'target:' prefix).

To do this I have replaced a system 'stat' call with a bfd_stat call.

However, doing this caused a regression in gdb.base/attach.exp.

The problem is that the bfd library caches open FILE* handles for bfd
objects that it has accessed, which is great for short-lived, non
interactive programs (e.g. the assembler, or objcopy, etc), however,
for GDB this caching causes us a problem.

If we open the main executable as a bfd then the bfd library will
cache the open FILE*.  If some time passes, maybe just sat at the GDB
prompt, or with the inferior running, and then later we use bfd_stat
to check if the underlying, on-disk file has changed, then the bfd
library will actually use fstat on the underlying file descriptor.
This is of course slightly different than using system stat on with
the on-disk file name.

If the on-disk file has changed then system stat will give results for
the current on-disk file.  But, if the bfd cache is still holding open
the file descriptor for the original on-disk file (from before the
change) then fstat will return a result based on the original file,
and so show no change as having happened.

This is a known problem in GDB, and so far this has been solved by
scattering bfd_cache_close_all() calls throughout GDB.  But, as I
said, in the next commit I've made a change and run into a
problem (gdb.base/attach.exp) where we are apparently missing a
bfd_cache_close_all() call.

Now I could solve this problem by adding a bfd_cache_close_all() call
before the bfd_stat call that I plan to add in the next commit, that
would for sure solve the problem, but feels a little crude.

Better I think would be to track down where the bfd is being opened
and add a corresponding bfd_cache_close_all() call elsewhere in GDB
once we've finished doing whatever it is that caused us to open the
bfd in the first place.

This second solution felt like the better choice, so I tracked the
problem down to elf_locate_base and fixed that.  But that just exposed
another problem in gdb_bfd_map_section which was also re-opening the
bfd, so I fixed this (with another bfd_cache_close_all() call), and
that exposed another issue in gdbarch_lookup_osabi... and at this
point I wondered if I was approaching this problem the wrong way...

.... And so, I wonder, is there a _better_ way to handle these
bfd_cache_close_all() calls?

I see two problems with the current approach:

  1. It's fragile.  Folk aren't always aware that they need to clear
  the bfd cache, and this feels like something that is easy to
  overlook in review.  So adding new code to GDB can innocently touch
  a bfd, which populates the cache, which will then be a bug that can
  lie hidden until an on-disk file just happens to change at the wrong
  time ... and GDB fails to spot the change.  Additionally,

  2. It's in efficient.  The caching is intended to stop the bfd
  library from continually having to re-open the on-disk file.  If we
  have a function that touches a bfd then often that function is the
  obvious place to call bfd_cache_close_all.  But if a single GDB
  command calls multiple functions, each of which touch the bfd, then
  we will end up opening and closing the same on-disk file multiple
  times.  It feels like we would be better postponing the
  bfd_cache_close_all call until some later point, then we can benefit
  from the bfd cache.

So, in this commit I propose a new approach.  We now clear the bfd
cache in two places:

  (a) Just before we display a GDB prompt.  We display a prompt after
  completing a command, and GDB is about to enter an idle state
  waiting for further input from the user (or in async mode, for an
  inferior event).  If while we are in this idle state the user
  changes the on-disk file(s) then we would like GDB to notice this
  the next time it leaves its idle state, e.g. the next time the user
  executes a command, or when an inferior event arrives,

  (b) When we resume the inferior.  In synchronous mode, resuming the
  inferior is another time when GDB is blocked and sitting idle, but
  in this case we don't display a prompt.  As with (a) above, when an
  inferior event arrives we want GDB to notice any changes to on-disk
  files.

It turns out that there are existing observers for both of these
cases (before_prompt and target_resumed respectively), so my initial
thought was that I should attach to these observers in gdb_bfd.c, and
in both cases call bfd_cache_close_all().

And this does indeed solve the gdb.base/attach.exp problem that I see
with the following commit.

However, I see a problem with this solution.

Both of the observers I'm using are exposed through the Python API as
events that a user can hook into.  The user can potentially run any
GDB command (using gdb.execute), so Python code might end up causing
some bfds to be reopened, and inserted into the cache.

To solve this one solution would be to add a bfd_cache_close_all()
call into gdbpy_enter::~gdbpy_enter().  Unfortunately, there's no
similar enter/exit object for Guile, though right now Guile doesn't
offer the same event API, so maybe we could just ignore that
problem... but this doesn't feel great.

So instead, I think a better solution might be to not use observers
for the bfd_cache_close_all() calls.  Instead, I'll call
bfd_cache_close_all() directly from core GDB after we've notified the
before_prompt and target_resumed observers, this was we can be sure
that the cache is cleared after the observers have run, and before GDB
enters an idle state.

This commit also removes all of the other bfd_cache_close_all() calls
from GDB.  My claim is that these are no longer needed.

Approved-By: Tom Tromey <tom@tromey.com>
2023-11-20 10:54:17 +00:00
Pedro Alves
21d4830415 gdb: clear step over information on thread exit (PR gdb/27338)
GDB doesn't handle correctly the case where a thread steps over a
breakpoint (using either in-line or displaced stepping), and the
executed instruction causes the thread to exit.

Using the test program included later in the series, this is what it
looks like with displaced-stepping, on x86-64 Linux, where we have two
displaced-step buffers:

  $ ./gdb -q -nx --data-directory=data-directory build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit -ex "b my_exit_syscall" -ex r
  Reading symbols from build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit...
  Breakpoint 1 at 0x123c: file src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S, line 68.
  Starting program: build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/usr/lib/../lib/libthread_db.so.1".
  [New Thread 0x7ffff7c5f640 (LWP 2915510)]
  [Switching to Thread 0x7ffff7c5f640 (LWP 2915510)]

  Thread 2 "step-over-threa" hit Breakpoint 1, my_exit_syscall () at src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S:68
  68              syscall
  (gdb) c
  Continuing.
  [New Thread 0x7ffff7c5f640 (LWP 2915524)]
  [Thread 0x7ffff7c5f640 (LWP 2915510) exited]
  [Switching to Thread 0x7ffff7c5f640 (LWP 2915524)]

  Thread 3 "step-over-threa" hit Breakpoint 1, my_exit_syscall () at src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S:68
  68              syscall
  (gdb) c
  Continuing.
  [New Thread 0x7ffff7c5f640 (LWP 2915616)]
  [Thread 0x7ffff7c5f640 (LWP 2915524) exited]
  [Switching to Thread 0x7ffff7c5f640 (LWP 2915616)]

  Thread 4 "step-over-threa" hit Breakpoint 1, my_exit_syscall () at src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S:68
  68              syscall
  (gdb) c
  Continuing.
  ... hangs ...

The first two times we do "continue", we displaced-step the syscall
instruction that causes the thread to exit.  When the thread exits,
the main thread, waiting on pthread_join, is unblocked.  It spawns a
new thread, which hits the breakpoint on the syscall again.  However,
infrun was never notified that the displaced-stepping threads are done
using the displaced-step buffer, so now both buffers are marked as
used.  So when we do the third continue, there are no buffers
available to displaced-step the syscall, so the thread waits forever
for its turn.

When trying the same but with in-line step over (displaced-stepping
disabled):

  $ ./gdb -q -nx --data-directory=data-directory \
  build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit \
    -ex "b my_exit_syscall" -ex "set displaced-stepping off" -ex r
  Reading symbols from build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit...
  Breakpoint 1 at 0x123c: file src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S, line 68.
  Starting program: build/binutils-gdb/gdb/testsuite/outputs/gdb.threads/step-over-thread-exit/step-over-thread-exit
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/usr/lib/../lib/libthread_db.so.1".
  [New Thread 0x7ffff7c5f640 (LWP 2928290)]
  [Switching to Thread 0x7ffff7c5f640 (LWP 2928290)]

  Thread 2 "step-over-threa" hit Breakpoint 1, my_exit_syscall () at src/binutils-gdb/gdb/testsuite/lib/my-syscalls.S:68
  68              syscall
  (gdb) c
  Continuing.
  [Thread 0x7ffff7c5f640 (LWP 2928290) exited]
  No unwaited-for children left.
  (gdb) i th
    Id   Target Id                                             Frame
    1    Thread 0x7ffff7c60740 (LWP 2928285) "step-over-threa" 0x00007ffff7f7c9b7 in __pthread_clockjoin_ex () from /usr/lib/libpthread.so.0

  The current thread <Thread ID 2> has terminated.  See `help thread'.
  (gdb) thread 1
  [Switching to thread 1 (Thread 0x7ffff7c60740 (LWP 2928285))]
  #0  0x00007ffff7f7c9b7 in __pthread_clockjoin_ex () from /usr/lib/libpthread.so.0
  (gdb) c
  Continuing.
  ^C^C
  ... hangs ...

The "continue" causes an in-line step to occur, meaning the main
thread is stopped while we step the syscall.  The stepped thread exits
when executing the syscall, the linux-nat target notices there are no
more resumed threads to be waited for, so returns
TARGET_WAITKIND_NO_RESUMED, which causes the prompt to return.  But
infrun never clears the in-line step over info.  So if we try
continuing the main thread, GDB doesn't resume it, because it thinks
there's an in-line step in progress that we need to wait for to
finish, and we are stuck there.

To fix this, infrun needs to be informed when a thread doing a
displaced or in-line step over exits.  We can do that with the new
target_set_thread_options mechanism which is optimal for only enabling
exit events of the thread that needs it; or, if that is not supported,
by using target_thread_events, which enables thread exit events for
all threads.  This is done by this commit.

This patch then modifies handle_inferior_event in infrun.c to clean up
any step-over the exiting thread might have been doing at the time of
the exit.  The cases to consider are:

 - the exiting thread was doing an in-line step-over with an all-stop
   target
 - the exiting thread was doing an in-line step-over with a non-stop
   target
 - the exiting thread was doing a displaced step-over with a non-stop
   target

The displaced-stepping buffer implementation in displaced-stepping.c
is modified to account for the fact that it's possible that we
"finish" a displaced step after a thread exit event.  The buffer that
the exiting thread was using is marked as available again and the
original instructions under the scratch pad are restored.  However, it
skips applying the fixup, which wouldn't make sense since the thread
does not exist anymore.

Another case that needs handling is if a displaced-stepping thread
exits, and the event is reported while we are in stop_all_threads.  We
should call displaced_step_finish in the handle_one function, in that
case.  It was already called in other code paths, just not the "thread
exited" path.

This commit doesn't make infrun ask the target to report the
TARGET_WAITKIND_THREAD_EXITED events yet, that'll be done later in the
series.

Note that "stop_print_frame = false;" line is moved to normal_stop,
because TARGET_WAITKIND_THREAD_EXITED can also end up with the event
transmorphed into TARGET_WAITKIND_NO_RESUMED.  Moving it to
normal_stop keeps it centralized.

Co-authored-by: Simon Marchi <simon.marchi@efficios.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=27338
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
Change-Id: I745c6955d7ef90beb83bcf0ff1d1ac8b9b6285a5
2023-11-13 14:16:11 +00:00
Pedro Alves
65c459abeb Thread options & clone events (core + remote)
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
2023-11-13 14:16:09 +00:00
Andrew Burgess
75b2eb97a4 gdb: call update_thread_list for $_inferior_thread_count function
I noticed that sometimes the value returned by $_inferior_thread_count
can become out of sync with the actual thread count of the inferior,
and will disagree with the number of threads reported by 'info
threads'.  This commit fixes this issue.

The cause of the problem is that 'info threads' includes a call to
update_thread_list, this can be seen in print_thread_info_1 in
thread.c, while $_inferior_thread_count doesn't include a similar
call, see the function inferior_thread_count_make_value also in
thread.c.

Of course, this is only a problem when GDB is running on a target that
relies on update_thread_list calls to learn about new threads,
e.g. remote or extended-remote targets.  Native targets generally
learn about new threads as soon as they appear and will not have this
problem.

I ran into this issue when writing a test for the next commit which
uses inferior function calls to add an remove threads from an
inferior.  But for testing I've made use of non-stop mode and
asynchronous inferior execution; by reading the inferior state I can
know when a new thread has been created, at which point I can print
$_inferior_thread_count while the inferior is still running.  This is
important, if I stop the inferior then GDB will pass through an
update_thread_list call in the normal stop code, which will
synchronise the thread list, after which $_inferior_thread_count will
report the correct value.

With this change in place $_inferior_thread_count is now correct.
2023-11-08 13:28:09 +00:00
Pedro Alves
9d7d58e726 gdb: centralize "[Thread ...exited]" notifications
Currently, each target backend is responsible for printing "[Thread
...exited]" before deleting a thread.  This leads to unnecessary
differences between targets, like e.g. with the remote target, we
never print such messages, even though we do print "[New Thread ...]".

E.g., debugging the gdb.threads/attach-many-short-lived-threads.exp
with gdbserver, letting it run for a bit, and then pressing Ctrl-C, we
currently see:

 (gdb) c
 Continuing.
 ^C[New Thread 3850398.3887449]
 [New Thread 3850398.3887500]
 [New Thread 3850398.3887551]
 [New Thread 3850398.3887602]
 [New Thread 3850398.3887653]
 ...

 Thread 1 "attach-many-sho" received signal SIGINT, Interrupt.
 0x00007ffff7e6a23f in __GI___clock_nanosleep (clock_id=clock_id@entry=0, flags=flags@entry=0, req=req@entry=0x7fffffffda80, rem=rem@entry=0x7fffffffda80)
     at ../sysdeps/unix/sysv/linux/clock_nanosleep.c:78
 78      in ../sysdeps/unix/sysv/linux/clock_nanosleep.c
 (gdb)

Above, we only see "New Thread" notifications, even though threads
were deleted.

After this patch, we'll see:

 (gdb) c
 Continuing.
 ^C[Thread 3558643.3577053 exited]
 [Thread 3558643.3577104 exited]
 [Thread 3558643.3577155 exited]
 [Thread 3558643.3579603 exited]
 ...
 [New Thread 3558643.3597415]
 [New Thread 3558643.3600015]
 [New Thread 3558643.3599965]
 ...

 Thread 1 "attach-many-sho" received signal SIGINT, Interrupt.
 0x00007ffff7e6a23f in __GI___clock_nanosleep (clock_id=clock_id@entry=0, flags=flags@entry=0, req=req@entry=0x7fffffffda80, rem=rem@entry=0x7fffffffda80)
     at ../sysdeps/unix/sysv/linux/clock_nanosleep.c:78
 78      in ../sysdeps/unix/sysv/linux/clock_nanosleep.c
 (gdb) q

This commit fixes this by moving the thread exit printing to common
code instead, triggered from within delete_thread (or rather,
set_thread_exited).

There's one wrinkle, though.  While most targest want to print:

 [Thread ... exited]

the Windows target wants to print:

 [Thread ... exited with code <exit_code>]

... and sometimes wants to suppress the notification for the main
thread.  To address that, this commits adds a delete_thread_with_code
function, only used by that target (so far).

This fix was originally posted as part of a larger series:

  https://inbox.sourceware.org/gdb-patches/20221212203101.1034916-1-pedro@palves.net/

But didn't really need to be part of that series.  In order to get
this fix merged sooner, I (Andrew Burgess) have rebased this commit
outside of the original series.  Any bugs introduced while splitting
this patch out and rebasing, are entirely my own.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30129
Co-Authored-By: Andrew Burgess <aburgess@redhat.com>
2023-08-23 09:57:38 +01:00
Pedro Alves
604fe2d97f gdb: make inferior::clear_thread_list always silent
After this commit:

  commit a78ef87574
  Date:   Wed Jun 22 18:10:00 2022 +0100

      Always emit =thread-exited notifications, even if silent

The function mi_interp::on_thread_exited (or mi_thread_exit as the
function was called back then) no longer makes use of the "silent"
parameter.

As a result there is no difference between inferior::clear_thread_list
with silent true or false, because:

  - None of the interpreter ::on_thread_exited functions rely on the
    silent parameter, and

  - None of GDB's thread_exit observers rely on the silent parameter
  either.

This commit removes the silent parameter from
inferior::clear_thread_list, and makes the function always silent.

This commit was originally part of a larger series:

  https://inbox.sourceware.org/gdb-patches/20221212203101.1034916-1-pedro@palves.net/

But didn't really need to be part of that series.  I had an interest
in seeing this patch merged:

  https://inbox.sourceware.org/gdb-patches/20221212203101.1034916-31-pedro@palves.net/

Which also didn't really need to be part of the larger series, but
does depend, at least a little, on this commit.  In order to get the
fix I'm interested in merged quicker, I (Andrew Burgess) have rebased
this commit outside of the original series.  Any bugs introduced while
splitting this patch out and rebasing, are entirely my own.

There should be no user visible changes after this commit.

Co-Authored-By: Andrew Burgess <aburgess@redhat.com>
2023-08-23 09:57:38 +01:00
Tom Tromey
d0ffdf6482 Pass unique_ptr to add_thread_with_info
This changes add_thread_with_info to accept a unique_ptr, making it
clear that it takes ownership of the passed-in pointer.

I can't test the AIX or Darwin changes, but I think they are
relatively obvious.
2023-08-10 10:50:37 -06:00
Simon Marchi
52d98df742 gdb: add interp::on_target_resumed method
Same idea as previous patches, but for target_resumed.

Change-Id: I66fa28d1d41a1f3c4fb0d6a470137d493eac3c8c
2023-05-30 15:07:26 -04:00
Simon Marchi
8e7af84345 gdb: add interp::on_thread_exited method
Same idea as previous patches, but for thread_exited.

Change-Id: I4be974cbe58cf635453fef503c2d77c82522cbd9
2023-05-30 15:07:26 -04:00
Simon Marchi
30e7e0a917 gdb: add interp::on_new_thread method
Same idea as previous patches, but for new_thread.

Change-Id: Ib70ae3421b736fd69d86c4e7c708bec349aa256c
2023-05-30 15:07:26 -04:00
Simon Marchi
77cd03e27c gdb: add interp::on_user_selected_context_changed method
Same as previous patches, but for user_selected_context_changed.

Change-Id: I40de15be897671227d4bcf3e747f0fd595f0d5be
2023-05-30 15:07:26 -04:00
Simon Marchi
348da4565b gdb: add maybe_switch_inferior function
Add the maybe_switch_inferior function, which ensures that the given
inferior is the current one.  Return an instantiated
scoped_restore_current_thread object only we actually needed to switch
inferior.

Returning a scoped_restore_current_thread requires it to be
move-constructible, so give it a move constructor.

Change-Id: I1231037102ed6166f2530399e8257ad937fb0569
Reviewed-By: Pedro Alves <pedro@palves.net>
2023-04-17 13:47:13 -04:00
Tankut Baris Aktemur
9278aa6171 gdb: boolify 'should_print_thread'
Convert the return type of 'should_print_thread' from int to bool.

Reviewed-By: Tom Tromey <tom@tromey.com>
2023-04-05 08:23:56 +02:00
Simon Marchi
9213a6d79a gdb: make find_thread_ptid a process_stratum_target method
Make find_thread_ptid (the overload that takes a process_stratum_target)
a method of process_stratum_target.

Change-Id: Ib190a925a83c6b93e9c585dc7c6ab65efbdd8629
Reviewed-By: Tom Tromey <tom@tromey.com>
2023-04-04 21:05:31 -04:00
Simon Marchi
3c8af02fa0 gdb: make find_thread_ptid an inferior method
Make find_thread_ptid (the overload that takes an inferior) a method of
struct inferior.

Change-Id: Ie5b9fa623ff35aa7ddb45e2805254fc8e83c9cd4
Reviewed-By: Tom Tromey <tom@tromey.com>
2023-04-04 21:05:30 -04:00
Ari Hannula
85413975d8 gdb: Remove extra if statement
The removed if statement is already checked in the parent if else
statement.

Co-Authored-By: Christina Schimpe <christina.schimpe@intel.com>
2023-03-31 13:49:21 +02:00
Andrew Burgess
442716d400 gdb: don't use the global thread-id in the saved breakpoints file
I noticed that breakpoint::print_recreate_thread was printing the
global thread-id.  This function is used to implement the 'save
breakpoints' command, and should be writing out suitable CLI commands
for recreating the current breakpoints.  The CLI does not use global
thread-ids, but instead uses the inferior specific thread-ids,
e.g. "2.1".

After some discussion on the mailing list it was suggested that the
most consistent solution would be for the saved breakpoints file to
always contain the inferior-qualified thread-id, so the file would
include "thread 1.1" instead of just "thread 1", even when there is
only a single inferior.

So, this commit adds print_full_thread_id, which is just like the
existing print_thread_id, only it always prints the inferior-qualified
thread-id.

I then update the existing print_thread_id to make use of this new
function, and finally, I update  breakpoint::print_recreate_thread to
also use this new function.

There's a multi-inferior test that confirms the saved breakpoints file
correctly includes the fully-qualified thread-id, and I've also
updated the single inferior test gdb.base/save-bp.exp to have it
validate that the saved breakpoints file includes the
inferior-qualified thread-id, even for this single inferior case.
2023-03-20 10:37:15 +00:00
Simon Marchi
287de65625 gdb, gdbserver, gdbsupport: fix whitespace issues
Replace spaces with tabs in a bunch of places.

Change-Id: If0f87180f1d13028dc178e5a8af7882a067868b0
2023-03-09 16:32:00 -05:00