Herbert Euler wrote:

>> > I tried M-x gdb to run emacs under gdb.  The command line was
>> >
>> >   gdb -i=mi ~/src/emacs/src/emacs
>> >
>> > and I got the error '(json-object-format ":" 44).  Here is the backtrace:
>>
>> I could reproduce your problem and I wrote a workaround which fixes the
>> bug for me. Could you please try the attached patch for gdb-mi.el?
>
> That patch works for me, too.  Thanks.

It's in the trunk now.

> 2. The command "shell" is broken: In M-x gdb,
>
>      shell ps aux | grep emacs
>
> results in no output; but in a "real" gdb, the output looks like this:
>
>      shell ps aux | grep emacs
>      &"shell ps aux | grep emacs\n"
>      xgp   4886  1.3  0.1 80796 25900 pts/1   T    09:38   0:08 emacs
>      xgp   4936  0.3  0.1 77688 22568 pts/10  T+   09:39   0:02 ./emacs
>      xgp   5209  0.0  0.1 28128 16548 pts/6   Ss+  09:46   0:00 /usr/local/bin/gdb -i=mi emacs
>      xgp   5353  0.4  0.1 28184 16584 pts/1   S+   09:49   0:00 gdb -i=mi emacs
>      xgp   5354  0.0  0.0 52800  976 pts/1    S+   09:49   0:00 bash -c ps aux | grep emacs
>      xgp   5356  0.0  0.0 51124  688 pts/1    S+   09:49   0:00 grep emacs
>      ^done

Output of GDB's shell command goes as is straight to the terminal
without being prefixed by stream identifier (~, @, & etc.) Thus it's
harder to distinguish where this output should go (to GUD buffer, to MI
parser etc.) I managed to produce a small patch which does the trick for
simple shell commands like yours, but don't expect it to work with
`top(1)` for example. I've attached the patch. Let me know if you notice
that it breaks something.