https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93469
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |UNCONFIRMED
Ever confirmed|1 |0
--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Thanks. This seems to be an Mac OS X feature, not a bug.
Selecting a specific POSIX version overrides the __STDC_VERSION and __cplusplus
values, and so names from newer POSIX standards (like aligned_alloc) are not
available.
IMO that is wrong, but it seems to be an intentional property of the OS X
system headers. Which means that you can't combine -std=c++2a with
-D_XOPEN_SOURCE=500. It produces an impossible combination where names required
to exist by one standard are required to _not_ exist by the other standard.
You could try reporting a radar bug and see if Apple really do consider this
correct behaviour.
