https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87995
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Can't reproduce on x86_64-linux, tried 2048 invocations of the testcase in a row, times various OMP_NUM_THREADS settings (32, 64, 1, 2, 4, 8). All on 16c32t machine. So, can you build it with additional -g and see where it aborts or how else it fails? What OMP_NUM_THREADS do you use? If it is an abort, can you replace it with printing the corresponding value and see what value isn't correctly reduced and what value do you get?
