diff --git a/src/x11/mutter-Xatomtype.h b/src/x11/mutter-Xatomtype.h
index 793a3aef3..ed3e1f781 100644
--- a/src/x11/mutter-Xatomtype.h
+++ b/src/x11/mutter-Xatomtype.h
@@ -60,10 +60,10 @@ SOFTWARE.
 #ifndef _XATOMTYPE_H_
 #define _XATOMTYPE_H_
 
-#define BOOL long
-#define SIGNEDINT long
-#define UNSIGNEDINT unsigned long
-#define RESOURCEID unsigned long
+#define BOOL int32_t
+#define SIGNEDINT int32_t
+#define UNSIGNEDINT uint32_t
+#define RESOURCEID uint32_t
 
 
 /* this structure may be extended, but do not change the order */