[PATCH] libstdc++: Use AS_IF in configure.ac

[Jonathan Wakely]

On Wed, 7 Jun 2023 at 15:42, Hans-Peter Nilsson <hp@axis.com> wrote:

> > Date: Tue, 6 Jun 2023 16:30:12 +0100
> > From: Jonathan Wakely via Gcc-patches <gcc-patches@gcc.gnu.org>
>
> > On Thu, 1 Jun 2023 at 16:59, Jonathan Wakely via Libstdc++ <
> > libstdc++@gcc.gnu.org> wrote:
> >
> > > Tested x86_64-linux. I'd appreciate a second set of eyeballs on this
> > > before I push it.
> > >
> >
> > Pushed to trunk now.
>
> ...as r14-1581-g97a5e8a2a48d16, after which (apparently)
> *all* linking libstdc++ tests for cris-elf (a "newlib
> target") get (for example):
>
> FAIL: 17_intro/freestanding.cc (test for excess errors)
> Excess errors:
> /x/cris-elf/pre/cris-elf/bin/ld: cannot find -liconv: No such file or
> directory
>
> (deduced from libstdc++.log and the commits in the range
> ce2188e4320c..585c660f041c where 4144 regressions in
> libstdc++ were introduced for cris-elf)
>

Gah. I tested building cris-elf but didn't run any tests.

I *thought* I compared the configure results before and after the patch
too, but I guess I missed something, or it didn't show up where I looked.



> From the generated configure and a brief RTFM for AS_IF, it
> looks almost like AS_IF was "miscompiled" and behaving
> literally AS_IF (!) in that the condition TEST1 (here
> [$GLIBCXX_IS_NATIVE] seems to be emitted *after* the
> RUN-IF-TRUE1 clause (the next 31 lines).  Not obvious what
> went wrong.  I even tried regenerating configure.  HTH.
>
>
Let's just revert it then. The manual says we should use AS_IF, but what we
had previously was working well enough. I'll figure out what happened here
later.