diff --git a/src/thread/pthread/SDL_systhread.c b/src/thread/pthread/SDL_systhread.c
index aa567d4e89..cd11acc67c 100644
--- a/src/thread/pthread/SDL_systhread.c
+++ b/src/thread/pthread/SDL_systhread.c
@@ -22,7 +22,7 @@
 
 #include <pthread.h>
 
-#if HAVE_PTHREAD_NP_H
+#ifdef HAVE_PTHREAD_NP_H
 #include <pthread_np.h>
 #endif