================== WARNING: ThreadSanitizer: data race (pid=) Write of size 8 at by thread T1 (mutexes: write M): #0 camlArray_elt$writer_ () #1 camlStdlib__Domain$body_ () Previous read of size 8 at by main thread (mutexes: write M): #0 camlArray_elt$reader_ () #1 camlArray_elt$entry () #2 caml_program () As if synchronized via sleep: #0 nanosleep () #1 wg_wait () #2 camlArray_elt$writer_ () #3 camlStdlib__Domain$body_ () Mutex M () created at: #0 pthread_mutex_init () #1 caml_plat_mutex_init () #2 caml_init_domains () #3 caml_init_gc () Mutex M () created at: #0 pthread_mutex_init () #1 caml_plat_mutex_init () #2 caml_init_domains () #3 caml_init_gc () Thread T1 (tid=, running) created by main thread at: #0 pthread_create () #1 caml_domain_spawn () #2 caml_c_call () #3 camlStdlib__Domain$spawn_ () #4 camlArray_elt$entry () #5 caml_program () SUMMARY: ThreadSanitizer: data race (:) in camlArray_elt$writer_ ================== ThreadSanitizer: reported 1 warnings