diff --git a/libc/include/pthread.h b/libc/include/pthread.h
index 3f59b91..7b8de81 100644
--- a/libc/include/pthread.h
+++ b/libc/include/pthread.h
@@ -91,7 +91,7 @@
 typedef long pthread_mutexattr_t;
 typedef long pthread_condattr_t;
 
-typedef int pthread_rwlockattr_t;
+typedef long pthread_rwlockattr_t;
 
 typedef struct {
   pthread_mutex_t lock;