[PATCH] [libstdc++] [testsuite] avoid arbitrary errno codes

[Jonathan Wakely]

On Fri, 12 Jul 2024 at 09:27, Alexandre Oliva <oliva@adacore.com> wrote:
>
> On Jul 11, 2024, Jonathan Wakely <jwakely@redhat.com> wrote:
>
> > There's no requirement that system_error uses strerror, that's just an
> > implementation detail.
>
> *nod*.  I meant it was more of a libc test in the case that relied on
> strerror.  But I fully agree that testing the C++ standard API makes
> perfect sense.  It's just that maybe we want workarounds for cases in
> which we implement in terms of libc, but libc doesn't live up to the
> standard.  Tolerating NULL returns from strerror would be an easy one;
> do we want that?  Checking strerror acceptable ranges (that don't
> trigger runtime errors) before calling it, and taking an alternate path
> when needed, that would be harder to do, and IMHO of dubious value.

Yes, handling a null result from strerror seems sensible if that's the reality.