diff --git a/src/api/z3.h b/src/api/z3.h
index 99929f33b..b29f1d6ba 100644
--- a/src/api/z3.h
+++ b/src/api/z3.h
@@ -21,7 +21,8 @@ Notes:
 #ifndef Z3_H_
 #define Z3_H_
 
-#include<stdio.h>
+#include <stdio.h>
+#include <stdbool.h>
 #include "z3_macros.h"
 #include "z3_api.h"
 #include "z3_ast_containers.h"