[Bug testsuite/112529] New: ACATS test c250002 uses illegal filename on APFS filesystem

["simon at pushface dot org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112529

            Bug ID: 112529
           Summary: ACATS test c250002 uses illegal filename on APFS
                    filesystem
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: testsuite
          Assignee: unassigned at gcc dot gnu.org
          Reporter: simon at pushface dot org
  Target Milestone: ---

This test checks that characters in Latin-1 above ASCII.Del can be used 
in identifiers, character literals and strings. Some of the identifiers 
are package names, so when the source is "gnatchopped' they become 
filenames.

In Apple's HFS+, although filesystem naming is UTF-8 (well, Apple's 
version), attempts to create files with Latin-1 names are allowed by 
silent name conversion: for example, given the filename c250002_á.ads, 
what is stored is c250002_%E1.ads.

In Apple's current APFS, however, this attempt results in failure:
   $ gnatchop c250002.aw 
   splitting c250002.aw into:
      c250002_0.ads
   cannot create c250002_?.ads
   cannot create c250002_?.adb
      c250002.adb

It would perhaps be ideal to report this test as 'unsupported' if run
on macOS, but this could be challenging given the rather ad-hoc nature 
of the scripts involved. Just not running the test at all wouldn't be 
right, since it runs OK on other operating systems.