[Bug d/104654] New: Errors in gthread.d when building against MinGW-w64 with --enable-threads=posix

[brechtsanders at users dot sourceforge.net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104654

            Bug ID: 104654
           Summary: Errors in gthread.d when building against MinGW-w64
                    with --enable-threads=posix
           Product: gcc
           Version: 11.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: d
          Assignee: ibuclaw at gdcproject dot org
          Reporter: brechtsanders at users dot sourceforge.net
  Target Milestone: ---

When building GCC (recently tried 11.2 snapshot 20220219) against MinGW-w64
with --enable-threads=posix the following D compiler errors occur:

r:\winlibs64-11.2.0ucrt\gcc-11-20220219\libphobos\libdruntime\gcc\gthread.d:46:30:
error: undefined identifier 'PTHREAD_ONCE_INIT', did you mean variable
'GTHREAD_ONCE_INIT'?
   46 |     enum GTHREAD_ONCE_INIT = PTHREAD_ONCE_INIT;
      |                              ^
r:\winlibs64-11.2.0ucrt\gcc-11-20220219\libphobos\libdruntime\gcc\gthread.d:44:29:
error: undefined identifier 'pthread_key_t'
   44 |     alias __gthread_key_t = pthread_key_t;
      |                             ^
r:\winlibs64-11.2.0ucrt\gcc-11-20220219\libphobos\libdruntime\gcc\gthread.d:45:30:
error: undefined identifier 'pthread_once_t'
   45 |     alias __gthread_once_t = pthread_once_t;
      |                              ^

>From what I gather things like pthread_key_t and pthread_once_t should probably
be defined in libphobos/libdruntime/core/sys/posix/sys/types.d and
PTHREAD_ONCE_INIT in libphobos/libdruntime/core/sys/posix/pthread.d

I noticed in libphobos/libdruntime/core/sys/posix/sys/types.d there is no
specific version() case for Windows/MinGW with POSIX threads.