diff --git a/server/thread.c b/server/thread.c
index a43db32..47208f3 100644
--- a/server/thread.c
+++ b/server/thread.c
@@ -19,6 +19,7 @@
  */
 
 #include "config.h"
+#include "wine/port.h"
 
 #include <assert.h>
 #include <errno.h>