GNU bug report logs - #63084
30.0.50; gud: set breakpoint while program is running

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: tatrics <at> gmail.com
To: bug-gnu-emacs <at> gnu.org
Subject: 30.0.50; gud: set breakpoint while program is running
Date: Tue, 25 Apr 2023 21:18:52 +0200

Hi!

When I try to set a breakpoint with
    "C-x C-a C-b" or (gud-break 1)
it doesn't seem to work.

But if I do
    (gud-call (format "break %s:%d" (buffer-file-name) (line-number-at-pos)))
it does work.



In GNU Emacs 30.0.50 (build 3, x86_64-pc-linux-gnu, GTK+ Version
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Repository revision: d664969544b13fe93a548c9908ce566f9b5cde9c
Repository branch: master
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Message #8 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: tatrics <at> gmail.com
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Wed, 26 Apr 2023 09:10:55 +0300

> From: tatrics <at> gmail.com
> Date: Tue, 25 Apr 2023 21:18:52 +0200
> 
> When I try to set a breakpoint with
>     "C-x C-a C-b" or (gud-break 1)
> it doesn't seem to work.

I cannot reproduce this: "C-x C-a C-b" does work for me.  Please
describe the recipe for reproducing the problem completely, starting
from "emacs -Q" and including all the commands you need to type/invoke
to reproduce the issue.

Thanks.

Message #11 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Wed, 26 Apr 2023 10:48:53 +0200

[Message part 1 (text/plain, inline)]

Oh, sorry. I tried on a different machine, and realized one have to use
"run&".

So, here's what I did:

$ cat main.c
    #include <stdio.h>
    #include <unistd.h>

    int main(void) {
        for (int i = 0; ; i++) {
            printf("%d\n", i);
            sleep(1);
        }
    }

$ gcc -g -o break main.c
$ emacs -Q main.c
M-x gdb RET
# in *gud-break*, NOTE it's "run&"
(gdb) run&
# in main.c
(goto-line 6)
(gud-break 1) ; or C-x C-a C-b
# nothing happens
M-: (gud-call "break 6") RET
# breakpoint is set and process execution is paused on hitting that
breakpoint

Hope that's more clear now!

On Wed, Apr 26, 2023 at 8:10 AM Eli Zaretskii <eliz <at> gnu.org> wrote:

> > From: tatrics <at> gmail.com
> > Date: Tue, 25 Apr 2023 21:18:52 +0200
> >
> > When I try to set a breakpoint with
> >     "C-x C-a C-b" or (gud-break 1)
> > it doesn't seem to work.
>
> I cannot reproduce this: "C-x C-a C-b" does work for me.  Please
> describe the recipe for reproducing the problem completely, starting
> from "emacs -Q" and including all the commands you need to type/invoke
> to reproduce the issue.
>
> Thanks.
>

[Message part 2 (text/html, inline)]

Message #14 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Wed, 26 Apr 2023 12:44:29 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Wed, 26 Apr 2023 10:48:53 +0200
> Cc: 63084 <at> debbugs.gnu.org
> 
> Oh, sorry. I tried on a different machine, and realized one have to use "run&".
> 
> So, here's what I did:
> 
> $ cat main.c
>     #include <stdio.h>
>     #include <unistd.h>
> 
>     int main(void) {
>         for (int i = 0; ; i++) {
>             printf("%d\n", i);
>             sleep(1);
>         }
>     }
> 
> $ gcc -g -o break main.c
> $ emacs -Q main.c
> M-x gdb RET
> # in *gud-break*, NOTE it's "run&"
> (gdb) run&
> # in main.c
> (goto-line 6)
> (gud-break 1) ; or C-x C-a C-b
> # nothing happens
> M-: (gud-call "break 6") RET
> # breakpoint is set and process execution is paused on hitting that breakpoint

What is the value of gdb-running and of gdb-non-stop after you "run&"
the program?

Message #17 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Ken Brown <kbrown <at> cornell.edu>
Cc: tatrics <at> gmail.com, 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Wed, 26 Apr 2023 14:19:31 +0300

> Cc: 63084 <at> debbugs.gnu.org
> Date: Wed, 26 Apr 2023 12:44:29 +0300
> From: Eli Zaretskii <eliz <at> gnu.org>
> 
> > From: TatriX <tatrics <at> gmail.com>
> > Date: Wed, 26 Apr 2023 10:48:53 +0200
> > Cc: 63084 <at> debbugs.gnu.org
> > 
> > Oh, sorry. I tried on a different machine, and realized one have to use "run&".
> > 
> > So, here's what I did:
> > 
> > $ cat main.c
> >     #include <stdio.h>
> >     #include <unistd.h>
> > 
> >     int main(void) {
> >         for (int i = 0; ; i++) {
> >             printf("%d\n", i);
> >             sleep(1);
> >         }
> >     }
> > 
> > $ gcc -g -o break main.c
> > $ emacs -Q main.c
> > M-x gdb RET
> > # in *gud-break*, NOTE it's "run&"
> > (gdb) run&
> > # in main.c
> > (goto-line 6)
> > (gud-break 1) ; or C-x C-a C-b
> > # nothing happens
> > M-: (gud-call "break 6") RET
> > # breakpoint is set and process execution is paused on hitting that breakpoint
> 
> What is the value of gdb-running and of gdb-non-stop after you "run&"
> the program?

Ken, could you please take a look at this bug report?  AFAICT, it has
something to do with the code you changed some 11 years ago (see
bug#9878).

Basically, what "M-x gdb" now does is send the "-gdb-set non-stop 1"
command, then, when we get a valid response for it, it sends the
"-gdb-set target-async 1" command.  So far so good, but when we get
the response for the latter, we send the "-list-target-features"
command and expect it to report "async" as one of the features, and if
not, we decide that non-stop mode is not supported.

My testing indicates that -list-target-features will only report
"async" after we run the program or attach to a process.  So we are
(almost) always disabling the non-stop mode, which doesn't seem right
to me.

So I'm interested to know how you tested this particular addition of
the -list-target-features command back then (if you remember).  Also,
what happens today when you start "M-x gdb" with a modern version of
GDB that does support target-async and non-stop mode.

The root cause that "C-x C-a C-b" doesn't work in the OP is that
gud-break (and any other command defined via gud-def) does nothing
when gud-running is non-nil.  This needs to be changed if we are
running the program in the background, but the question is how to know
that reliably, and that is related -list-target-features, among other
things.

TIA

Message #20 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org, Ken Brown <kbrown <at> cornell.edu>
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Wed, 26 Apr 2023 13:49:11 +0200

[Message part 1 (text/plain, inline)]

> What is the value of gdb-running and of gdb-non-stop after you "run&"
> the program?

ELISP> gdb-running
*** Eval error ***  Symbol’s value as variable is void: gdb-running
ELISP> gud-running
t
ELISP> gdb-non-stop
nil

On Wed, Apr 26, 2023 at 1:19 PM Eli Zaretskii <eliz <at> gnu.org> wrote:

> > Cc: 63084 <at> debbugs.gnu.org
> > Date: Wed, 26 Apr 2023 12:44:29 +0300
> > From: Eli Zaretskii <eliz <at> gnu.org>
> >
> > > From: TatriX <tatrics <at> gmail.com>
> > > Date: Wed, 26 Apr 2023 10:48:53 +0200
> > > Cc: 63084 <at> debbugs.gnu.org
> > >
> > > Oh, sorry. I tried on a different machine, and realized one have to
> use "run&".
> > >
> > > So, here's what I did:
> > >
> > > $ cat main.c
> > >     #include <stdio.h>
> > >     #include <unistd.h>
> > >
> > >     int main(void) {
> > >         for (int i = 0; ; i++) {
> > >             printf("%d\n", i);
> > >             sleep(1);
> > >         }
> > >     }
> > >
> > > $ gcc -g -o break main.c
> > > $ emacs -Q main.c
> > > M-x gdb RET
> > > # in *gud-break*, NOTE it's "run&"
> > > (gdb) run&
> > > # in main.c
> > > (goto-line 6)
> > > (gud-break 1) ; or C-x C-a C-b
> > > # nothing happens
> > > M-: (gud-call "break 6") RET
> > > # breakpoint is set and process execution is paused on hitting that
> breakpoint
> >
> > What is the value of gdb-running and of gdb-non-stop after you "run&"
> > the program?
>
> Ken, could you please take a look at this bug report?  AFAICT, it has
> something to do with the code you changed some 11 years ago (see
> bug#9878).
>
> Basically, what "M-x gdb" now does is send the "-gdb-set non-stop 1"
> command, then, when we get a valid response for it, it sends the
> "-gdb-set target-async 1" command.  So far so good, but when we get
> the response for the latter, we send the "-list-target-features"
> command and expect it to report "async" as one of the features, and if
> not, we decide that non-stop mode is not supported.
>
> My testing indicates that -list-target-features will only report
> "async" after we run the program or attach to a process.  So we are
> (almost) always disabling the non-stop mode, which doesn't seem right
> to me.
>
> So I'm interested to know how you tested this particular addition of
> the -list-target-features command back then (if you remember).  Also,
> what happens today when you start "M-x gdb" with a modern version of
> GDB that does support target-async and non-stop mode.
>
> The root cause that "C-x C-a C-b" doesn't work in the OP is that
> gud-break (and any other command defined via gud-def) does nothing
> when gud-running is non-nil.  This needs to be changed if we are
> running the program in the background, but the question is how to know
> that reliably, and that is related -list-target-features, among other
> things.
>
> TIA
>

[Message part 2 (text/html, inline)]

Message #23 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: kbrown <at> cornell.edu
Cc: tatrics <at> gmail.com, 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Fri, 05 May 2023 08:52:26 +0300

Ping!  Ken, could you please look into this, if you have time?

> Cc: tatrics <at> gmail.com, 63084 <at> debbugs.gnu.org
> Date: Wed, 26 Apr 2023 14:19:31 +0300
> From: Eli Zaretskii <eliz <at> gnu.org>
> 
> > Cc: 63084 <at> debbugs.gnu.org
> > Date: Wed, 26 Apr 2023 12:44:29 +0300
> > From: Eli Zaretskii <eliz <at> gnu.org>
> > 
> > > From: TatriX <tatrics <at> gmail.com>
> > > Date: Wed, 26 Apr 2023 10:48:53 +0200
> > > Cc: 63084 <at> debbugs.gnu.org
> > > 
> > > Oh, sorry. I tried on a different machine, and realized one have to use "run&".
> > > 
> > > So, here's what I did:
> > > 
> > > $ cat main.c
> > >     #include <stdio.h>
> > >     #include <unistd.h>
> > > 
> > >     int main(void) {
> > >         for (int i = 0; ; i++) {
> > >             printf("%d\n", i);
> > >             sleep(1);
> > >         }
> > >     }
> > > 
> > > $ gcc -g -o break main.c
> > > $ emacs -Q main.c
> > > M-x gdb RET
> > > # in *gud-break*, NOTE it's "run&"
> > > (gdb) run&
> > > # in main.c
> > > (goto-line 6)
> > > (gud-break 1) ; or C-x C-a C-b
> > > # nothing happens
> > > M-: (gud-call "break 6") RET
> > > # breakpoint is set and process execution is paused on hitting that breakpoint
> > 
> > What is the value of gdb-running and of gdb-non-stop after you "run&"
> > the program?
> 
> Ken, could you please take a look at this bug report?  AFAICT, it has
> something to do with the code you changed some 11 years ago (see
> bug#9878).
> 
> Basically, what "M-x gdb" now does is send the "-gdb-set non-stop 1"
> command, then, when we get a valid response for it, it sends the
> "-gdb-set target-async 1" command.  So far so good, but when we get
> the response for the latter, we send the "-list-target-features"
> command and expect it to report "async" as one of the features, and if
> not, we decide that non-stop mode is not supported.
> 
> My testing indicates that -list-target-features will only report
> "async" after we run the program or attach to a process.  So we are
> (almost) always disabling the non-stop mode, which doesn't seem right
> to me.
> 
> So I'm interested to know how you tested this particular addition of
> the -list-target-features command back then (if you remember).  Also,
> what happens today when you start "M-x gdb" with a modern version of
> GDB that does support target-async and non-stop mode.
> 
> The root cause that "C-x C-a C-b" doesn't work in the OP is that
> gud-break (and any other command defined via gud-def) does nothing
> when gud-running is non-nil.  This needs to be changed if we are
> running the program in the background, but the question is how to know
> that reliably, and that is related -list-target-features, among other
> things.
> 
> TIA
> 
> 
> 
> 

Message #26 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: tatrics <at> gmail.com
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Fri, 05 May 2023 08:53:42 +0300

Ping!  Could you please answer my questions below?  Knowing the
answers is necessary for investigating this issue.

Thanks.

> Cc: 63084 <at> debbugs.gnu.org
> Date: Wed, 26 Apr 2023 12:44:29 +0300
> From: Eli Zaretskii <eliz <at> gnu.org>
> 
> > From: TatriX <tatrics <at> gmail.com>
> > Date: Wed, 26 Apr 2023 10:48:53 +0200
> > Cc: 63084 <at> debbugs.gnu.org
> > 
> > Oh, sorry. I tried on a different machine, and realized one have to use "run&".
> > 
> > So, here's what I did:
> > 
> > $ cat main.c
> >     #include <stdio.h>
> >     #include <unistd.h>
> > 
> >     int main(void) {
> >         for (int i = 0; ; i++) {
> >             printf("%d\n", i);
> >             sleep(1);
> >         }
> >     }
> > 
> > $ gcc -g -o break main.c
> > $ emacs -Q main.c
> > M-x gdb RET
> > # in *gud-break*, NOTE it's "run&"
> > (gdb) run&
> > # in main.c
> > (goto-line 6)
> > (gud-break 1) ; or C-x C-a C-b
> > # nothing happens
> > M-: (gud-call "break 6") RET
> > # breakpoint is set and process execution is paused on hitting that breakpoint
> 
> What is the value of gdb-running and of gdb-non-stop after you "run&"
> the program?
> 
> 
> 
> 

Message #29 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Fri, 5 May 2023 09:15:19 +0200

> Could you please answer my questions below?

Sorry, I'm not sure what questions you are referring to.

>> What is the value of gdb-running and of gdb-non-stop after you "run&"
>> the program?
> gud-running is t
> gdb-non-stop is nil

in case my last email didn't get through.

Message #32 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Sat, 06 May 2023 14:43:17 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Fri, 5 May 2023 09:15:19 +0200
> Cc: 63084 <at> debbugs.gnu.org
> 
> > Could you please answer my questions below?
> 
> Sorry, I'm not sure what questions you are referring to.
> 
> >> What is the value of gdb-running and of gdb-non-stop after you "run&"
> >> the program?
> > gud-running is t
> > gdb-non-stop is nil
> 
> in case my last email didn't get through.

Thanks.  The value of gdb-non-stop is the problem: it basically means
that gdb-mi thinks GDB doesn't support async execution, and therefore
doesn't behave accordingly, which is evidenced by gud-running being
non-nil.

I hope Ken responds soon, because I think we need to redesign the part
which asks GDB about support for target-async and non-stop mode.

Message #35 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Sat, 27 May 2023 23:22:52 +0200

While we waiting for a reply, may I ask what is the relationship
between gdb-mi.el and gud.el?

Message #38 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org, kbrown <at> cornell.edu
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Sun, 28 May 2023 08:28:28 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Sat, 27 May 2023 23:22:52 +0200
> Cc: 63084 <at> debbugs.gnu.org
> 
> While we waiting for a reply

Actually, I've given up on waiting for a reply (Ken, are you there?),
so now we basically wait for me to get enough free time to work on
this non-trivial issue.  I've meanwhile set up one of my systems to
support asynchronous and non-stop execution in GDB, so that I could
test the changes.  Stay tuned.

> may I ask what is the relationship between gdb-mi.el and gud.el?

gdb-mi.el is basically a (very significant) extension of gud.el.
gdb-mi.el builds on the basic features provided by gud.el for GDB, and
adds a lot of stuff of its own, both to support the GDB/MI protocol
and provide a GUI front-end display, similar to other debugging UIs.

Message #41 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org, kbrown <at> cornell.edu
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Sun, 28 May 2023 23:10:21 +0200

[Message part 1 (text/plain, inline)]

Nice! Thank you!

I tend to use `M-x gdb` with `gdb-many-windows` disabled but easily
reachable via a custom keybinding that toggles it.

One feature I'm really missing is a variable watcher.

There's a locals view which is useful sometimes, but gets messy when
there are handfull of variables in scope.  Then there's a speedbar,
but as far as I can tell it's impossible to make it into a regular
window, which means it and cannot participate in my regular emacs
window workflow, which is sub-optimal. But the biggest issue with it
is that it forgets what was added to it on every program restart,
making it pretty much unusable for my needs.

I've played a bit with gdb-mi and managed to make something that
somewhat works. Please check a screenshot in the attachment.

I can add variables to watch via the minibuffer. They get updated in
the *gdb-watch* window through `-data-evaluate-expression` in the
`gdb-stopped-functions` hook.

I've also started looking at "GDB/MI Variable Objects"(1) which looks
like a proper way to add that functionality. But it requires a bit
more work.

How do you feel about having something similar in gdb-mi?

1: https://sourceware.org/gdb/onlinedocs/gdb/GDB_002fMI-Variable-Objects.html#GDB_002fMI-Variable-Objects

[2023-05-28-225817_3838x2124_scrot.png (image/png, attachment)]

Message #44 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org, kbrown <at> cornell.edu
Subject: Re: bug#63084: 30.0.50; gud: set breakpoint while program is running
Date: Mon, 29 May 2023 14:45:22 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Sun, 28 May 2023 23:10:21 +0200
> Cc: 63084 <at> debbugs.gnu.org, kbrown <at> cornell.edu
> 
> One feature I'm really missing is a variable watcher.
> 
> There's a locals view which is useful sometimes, but gets messy when
> there are handfull of variables in scope.  Then there's a speedbar,
> but as far as I can tell it's impossible to make it into a regular
> window, which means it and cannot participate in my regular emacs
> window workflow, which is sub-optimal.

I'm not sure I understand: how does using Speedbar interfere with your
workflow?

> But the biggest issue with it is that it forgets what was added to
> it on every program restart, making it pretty much unusable for my
> needs.

I'm not sure how can this work otherwise: watchpoints are usually
context-dependent, and are automatically deleted when their component
variables go out of scope.  How would you know when to re-apply
watchpoint settings when you re-run the program?  You must be in the
correct call-stack frame to be able to do that, or else all you get as
an error from GDB.

The way to automate re-application of watchpoints is to create one or
more breakpoints, at suitable locations in the program, and have the
"commands" of those breakpoints insert watchpoints, then continue the
program.  This is usually done in a .gdbinit file (or some other
script file read by GDB), and I'm not sure I understand how you can do
that programmatically, since Emacs is not really aware of GDB
call-stack frames.

> I've played a bit with gdb-mi and managed to make something that
> somewhat works. Please check a screenshot in the attachment.
> 
> I can add variables to watch via the minibuffer. They get updated in
> the *gdb-watch* window through `-data-evaluate-expression` in the
> `gdb-stopped-functions` hook.
> 
> I've also started looking at "GDB/MI Variable Objects"(1) which looks
> like a proper way to add that functionality. But it requires a bit
> more work.

AFAIK, Variable Objects cannot be replacements for watchpoints, since
GDB must actively poll for updates of the values, as opposed to
watchpoints, whose changes cause the program to stop.

> How do you feel about having something similar in gdb-mi?

It would be a useful addition, but I'd expect it to be easily doable
by reusing what we currently have (I'm not sure I understand why we
currently insist on Speedbar for these displays).

Anyway, this should be discussed as a separate feature request, not as
part of this bug report.

Message #49 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Tue, 11 Jul 2023 09:31:18 +0200

Hi!
I've compiled latest master and still can't set breakpoints while the
program is running.
Am I missing anything in the config perhaps?

Message #52 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Tue, 11 Jul 2023 15:24:58 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Tue, 11 Jul 2023 09:31:18 +0200
> 
> I've compiled latest master and still can't set breakpoints while the
> program is running.
> Am I missing anything in the config perhaps?

Works for me.  What exactly did you try?  Please show the exact steps.

I did the steps shown here:

  https://debbugs.gnu.org/cgi/bugreport.cgi?bug=63084#11

and after "C-x C-a C-b", the program stopped on line 6, as expected.
Then I typed "c&", and the program printed one more line, and stopped,
again as expected.  If I remove the breakpoint with "C-x C-a C-d" and
type "c&", the program starts running without stopping again.

If those steps don't work for you, please tell which GDB version are
you using (I used GDB 12.1) and on what OS.

Message #55 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Tue, 11 Jul 2023 17:30:16 +0200

I've used the same example with the same set of steps.

> If those steps don't work for you, please tell which GDB version are

GNU gdb (GDB) 13.1

Linux home 6.3.8-arch1-1 #1 SMP PREEMPT_DYNAMIC Wed, 14 Jun 2023
20:10:31 +0000 x86_64 GNU/Linux

GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.38,
cairo version 1.17.8) of 2023-07-06

Message #58 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Tue, 11 Jul 2023 18:56:10 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Tue, 11 Jul 2023 17:30:16 +0200
> Cc: 63084 <at> debbugs.gnu.org
> 
> I've used the same example with the same set of steps.
> 
> > If those steps don't work for you, please tell which GDB version are
> 
> GNU gdb (GDB) 13.1
> 
> Linux home 6.3.8-arch1-1 #1 SMP PREEMPT_DYNAMIC Wed, 14 Jun 2023
> 20:10:31 +0000 x86_64 GNU/Linux
> 
> GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.38,
> cairo version 1.17.8) of 2023-07-06

So what doesn't work, and how does it not work?  Are you saying that
you see the same behavior as before the recent changes in gdb-mi.el?
Including the fact that after "run&" the value of gud-running is t?
(It should be nil.)

If you try the same steps in "emacs -Q", does it work?  What about
"emacs -Q -nw"?

Also, do you have anything in your .gdbinit files, both system-wide
and your private ones?  If you do, maybe those settings somehow get in
the way?

Message #61 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: TatriX <tatrics <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Tue, 11 Jul 2023 19:49:15 +0200

> So what doesn't work, and how does it not work?
Did a few more tests to see what actually happens.
I'm running the same code as before in "emacs -Q"
    > run &
    C-x C-a C-b ;; sets breakpoint successfully
    C-x C-a C-d ;; removes breakpoint
    > c &
After that program continues, but 'gud-running' is now t, even if I ">
kill" the program and "> run&" it again.

Message #64 received at 63084 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: TatriX <tatrics <at> gmail.com>
Cc: 63084 <at> debbugs.gnu.org
Subject: Re: bug#63084: closed (Re: bug#64186: Patch: Suppress deprecated
 '-gdb-set target-async' warning message in gdb-mi.el)
Date: Thu, 13 Jul 2023 09:26:07 +0300

> From: TatriX <tatrics <at> gmail.com>
> Date: Tue, 11 Jul 2023 19:49:15 +0200
> Cc: 63084 <at> debbugs.gnu.org
> 
> > So what doesn't work, and how does it not work?
> Did a few more tests to see what actually happens.
> I'm running the same code as before in "emacs -Q"
>     > run &
>     C-x C-a C-b ;; sets breakpoint successfully
>     C-x C-a C-d ;; removes breakpoint
>     > c &
> After that program continues, but 'gud-running' is now t, even if I ">
> kill" the program and "> run&" it again.

So it's a separate problem: some code sets gud-running even though
this is async mode.

Can you figure which function sets gud-running when you type "c&"?  My
first suspect is gdb-starting, because it sets gud-running
unconditionally instead of doing this:

  (when (not gdb-non-stop)
    (setq gud-running t))

like gdb-running does.  The other suspect is gdb-update-gud-running.

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