[PATCH] libstdc++: testsuite: skip fs space tests if not available

[Jonathan Wakely]

On Wed, 22 Jun 2022 at 07:28, Alexandre Oliva via Libstdc++
<libstdc++@gcc.gnu.org> wrote:
>
>
> The do_space function is defined in ways that are useful, or that fail
> immediately, depending on various macros.  When it fails immediately,
> the filesystem space.cc tests fail noisily, but the fail is entirely
> expected.
>
> Define HAVE_SPACE in the space.cc tests, according to the macros that
> select implementations of do_space, and use it to skip tests that are
> expected to fail.
>
> Regstrapped on x86_64-linux-gnu, also tested with a cross to
> aarch64-rtems6.  Ok to install?

OK.

This could be done once in testsuite_fs.h as well.