Fixing MacOS build breakage introduced in #1191.
@ -87,7 +87,7 @@ gpr_thd_id gpr_thd_currentid(void) {
}
void gpr_thd_join(gpr_thd_id t) {
pthread_join(t, NULL);
pthread_join((pthread_t)t, NULL);
#endif /* GPR_POSIX_SYNC */