diff --git a/src/config.h b/src/config.h
index b7e0a4f1e..addb9c3f4 100644
--- a/src/config.h
+++ b/src/config.h
@@ -256,7 +256,7 @@ void setproctitle(const char *fmt, ...);
 #define redis_set_thread_title(name) rename_thread(find_thread(0), name)
 #else
 #if (defined __APPLE__ && defined(MAC_OS_X_VERSION_10_7))
-int pthread_setname_np(const char *name);
+extern "C" int pthread_setname_np(const char *name);
 #include <pthread.h>
 #define redis_set_thread_title(name) pthread_setname_np(name)
 #else