Re: [PATCH] Do not write negative PID or TID in remote protocol

[Kevin Buettner <kevinb@redhat.com>]

On Wed, 11 Mar 2026 14:21:52 -0600
Tom Tromey <tromey@adacore.com> wrote:

> From: Tom Tromey <tromey@adacore.com>
> To: gdb-patches@sourceware.org
> Cc: Tom Tromey <tromey@adacore.com>
> Subject: [PATCH] Do not write negative PID or TID in remote protocol
> Date: Wed, 11 Mar 2026 14:21:52 -0600
> 
> Currently both gdb and gdbserver can write a negative number for the
> PID or TID.  However, the only negative value that really makes sense
> is the special case of "-1" -- in other cases if the PID or TID has
> the high bit set, it should still be written as a positive number.
> 
> This patch attempts to fix the bug.  I am not really sure how to test
> it.
> 
> As an aside there seems to be more low-level RSP code that could be
> shared here.
> 
> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=25111
> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33979

LGTM.

FWIW, Claude Opus 4.6 suggested that unit test might be employed for
testing these changes.  I'm not sure that's necessary, but I thought I'd
mention it.

Approved-by: Kevin Buettner <kevinb@redhat.com>