[Bug libgomp/105745] New: Conditional OpenMP directive fails with GCC 12

[reiter.christoph at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105745

            Bug ID: 105745
           Summary: Conditional OpenMP directive fails with GCC 12
           Product: gcc
           Version: 12.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libgomp
          Assignee: unassigned at gcc dot gnu.org
          Reporter: reiter.christoph at gmail dot com
                CC: jakub at gcc dot gnu.org
  Target Milestone: ---

Downstream issue: https://github.com/msys2/MINGW-packages/issues/11729

The following example crashes with GCC 12.1.0, but works fine with GCC 11.3.0:

// g++ -fopenmp -o broken.exe broken.c; ./broken.exe; echo $?
int main() {
    #pragma omp parallel for if (0)
    for (int idx = 0; idx < 0; ++idx) { }
    return 0;
}

* Removing the "if (0)" condition makes it work again
* Replacing libgomp-1.dll with the one from GCC 11.3 also makes things work
again.
* Another example that crashes is "#pragma omp for schedule(dynamic)"

This is on 32/64 bit Windows.