options/posix: Add PTHREAD_RWLOCK_INITIALIZER
@@ -39,6 +39,7 @@ extern "C" {
#define PTHREAD_ONCE_INIT {0}
#define PTHREAD_COND_INITIALIZER {0}
#define PTHREAD_MUTEX_INITIALIZER {0, 0, 0}
+#define PTHREAD_RWLOCK_INITIALIZER {0, 0, 0}
// TODO: move to own file and include in sys/types.h
struct __mlibc_threadattr {
