diff --git a/include/cutils/threads.h b/include/cutils/threads.h
index bb9fdb8..3133cdb 100644
--- a/include/cutils/threads.h
+++ b/include/cutils/threads.h
@@ -32,6 +32,7 @@
 #if !defined(_WIN32)
 
 #include  <pthread.h>
+#include  <sys/types.h>
 
 typedef struct {
     pthread_mutex_t   lock;