diff --git a/native/jni/src/binary_format.h b/native/jni/src/binary_format.h
index 86410fb..d1e8316 100644
--- a/native/jni/src/binary_format.h
+++ b/native/jni/src/binary_format.h
@@ -17,7 +17,7 @@
 #ifndef LATINIME_BINARY_FORMAT_H
 #define LATINIME_BINARY_FORMAT_H
 
-#include <cctype>
+#include <cstdlib>
 #include <limits>
 #include <map>
 #include "bloom_filter.h"