[RFA/RFC] testsuite: gdb_run_cmd tweak

[Stan Shebs]

Michael Snyder wrote:

> This just adds a regular expression to prevent gdb_run_cmd
> from choking on the msg that gdb emits when it detects that
> the file has changed and re-reads the symbols.
>
> I honestly don't remember the circumstances that caused me
> to add this -- it's been sitting in my sandbox for a while.
> Thought it would be better to offer it up than to throw it
> away...

Wouldn't a message like this be symptomatic of failure
in GDB's executable date detection code, or in the executable
production bits? I think we'd only want this suppression
if the situation were explicitly known to be unavoidable,
like an outside compiler we couldn't control, or a known
OS bug, and even then we'd want to conditionalize on config.

Stan