diff --git a/Zend/zend_types.h b/Zend/zend_types.h
index df64541749d..1b1f804a3c7 100644
--- a/Zend/zend_types.h
+++ b/Zend/zend_types.h
@@ -24,6 +24,8 @@
 
 #include "zend_portability.h"
 #include "zend_long.h"
+#include "zend_type_info.h" // for MAY_BE_*
+
 #include <stdbool.h>
 
 #ifdef __SSE2__