partial output of parallel | major_gc_wait_backup

==================
WARNING: ThreadSanitizer: data race (pid=434994)
  Read of size 8 at 0x562618d443d8 by main thread (mutexes: write M89):
    #0 caml_compute_gc_stats runtime/gc_stats.c:177 (major_gc_wait_backup.opt+0xfd996)
    #1 caml_gc_quick_stat runtime/gc_ctrl.c:61 (major_gc_wait_backup.opt+0xfbee4)
    #2 caml_c_call <null> (major_gc_wait_backup.opt+0x1221e7)
    #3 camlMajor_gc_wait_backup.major_collections_275 <null> (major_gc_wait_backup.opt+0x63cd8)
    #4 camlMajor_gc_wait_backup.entry <null> (major_gc_wait_backup.opt+0x63f0a)
    #5 caml_program <null> (major_gc_wait_backup.opt+0x6142e)
    #6 caml_start_program <null> (major_gc_wait_backup.opt+0x122463)
    #7 caml_startup_common runtime/startup_nat.c:132 (major_gc_wait_backup.opt+0x1216bd)
    #8 caml_startup_exn runtime/startup_nat.c:139 (major_gc_wait_backup.opt+0x1216f9)
    #9 caml_startup runtime/startup_nat.c:144 (major_gc_wait_backup.opt+0x121727)
    #10 caml_main runtime/startup_nat.c:151 (major_gc_wait_backup.opt+0x121767)
    #11 main runtime/main.c:37 (major_gc_wait_backup.opt+0x107855)

  Previous write of size 8 at 0x562618d443d8 by thread T5 (mutexes: write M93):
    #0 caml_collect_heap_stats_sample runtime/shared_heap.c:652 (major_gc_wait_backup.opt+0x1160cc)
    #1 caml_collect_gc_stats_sample runtime/gc_stats.c:125 (major_gc_wait_backup.opt+0xfd7ee)
    #2 caml_stw_empty_minor_heap_no_major_slice runtime/minor_gc.c:714 (major_gc_wait_backup.opt+0x11050a)
    #3 caml_stw_empty_minor_heap runtime/minor_gc.c:756 (major_gc_wait_backup.opt+0x110656)
    #4 stw_handler runtime/domain.c:1287 (major_gc_wait_backup.opt+0xf2487)
    #5 handle_incoming runtime/domain.c:314 (major_gc_wait_backup.opt+0xf2487)
    #6 caml_handle_incoming_interrupts runtime/domain.c:327 (major_gc_wait_backup.opt+0xf24d4)
    #7 backup_thread_func runtime/domain.c:953 (major_gc_wait_backup.opt+0xf25c0)

  Location is global 'sampled_gc_stats' of size 13312 at 0x562618d44340 (major_gc_wait_backup.opt+0x1a33d8)

  Mutex M89 (0x562618d3b308) created at:
    #0 pthread_mutex_init /usr/src/debug/gcc/gcc/libsanitizer/tsan/tsan_interceptors_posix.cpp:1295 (libtsan.so.2+0x57446)
    #1 caml_plat_mutex_init runtime/platform.c:55 (major_gc_wait_backup.opt+0x1120dd)
    #2 caml_init_domains runtime/domain.c:873 (major_gc_wait_backup.opt+0xf1569)
    #3 caml_init_gc runtime/gc_ctrl.c:347 (major_gc_wait_backup.opt+0xfd1fc)
    #4 caml_startup_common runtime/startup_nat.c:111 (major_gc_wait_backup.opt+0x121595)
    #5 caml_startup_exn runtime/startup_nat.c:139 (major_gc_wait_backup.opt+0x1216f9)
    #6 caml_startup runtime/startup_nat.c:144 (major_gc_wait_backup.opt+0x121727)
    #7 caml_main runtime/startup_nat.c:151 (major_gc_wait_backup.opt+0x121767)
    #8 main runtime/main.c:37 (major_gc_wait_backup.opt+0x107855)

  Mutex M93 (0x562618d3b420) created at:
    #0 pthread_mutex_init /usr/src/debug/gcc/gcc/libsanitizer/tsan/tsan_interceptors_posix.cpp:1295 (libtsan.so.2+0x57446)
    #1 caml_plat_mutex_init runtime/platform.c:55 (major_gc_wait_backup.opt+0x1120dd)
    #2 caml_init_domains runtime/domain.c:873 (major_gc_wait_backup.opt+0xf1569)
    #3 caml_init_gc runtime/gc_ctrl.c:347 (major_gc_wait_backup.opt+0xfd1fc)
    #4 caml_startup_common runtime/startup_nat.c:111 (major_gc_wait_backup.opt+0x121595)
    #5 caml_startup_exn runtime/startup_nat.c:139 (major_gc_wait_backup.opt+0x1216f9)
    #6 caml_startup runtime/startup_nat.c:144 (major_gc_wait_backup.opt+0x121727)
    #7 caml_main runtime/startup_nat.c:151 (major_gc_wait_backup.opt+0x121767)
    #8 main runtime/main.c:37 (major_gc_wait_backup.opt+0x107855)

  Thread T5 (tid=435186, running) created by thread T4 at:
    #0 pthread_create /usr/src/debug/gcc/gcc/libsanitizer/tsan/tsan_interceptors_posix.cpp:1001 (libtsan.so.2+0x670c9)
    #1 install_backup_thread runtime/domain.c:1016 (major_gc_wait_backup.opt+0xf0286)
    #2 domain_thread_func runtime/domain.c:1089 (major_gc_wait_backup.opt+0xf1811)

SUMMARY: ThreadSanitizer: data race runtime/gc_stats.c:177 in caml_compute_gc_stats
==================