diff --git a/libs/fst/scanner.cc b/libs/fst/scanner.cc
index e09aecd5a0..d94703d5c5 100644
--- a/libs/fst/scanner.cc
+++ b/libs/fst/scanner.cc
@@ -19,6 +19,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <vector>
 
 #ifdef COMPILER_MSVC