diff --git a/src/lisp/lexer.cpp b/src/lisp/lexer.cpp
index 0086e8523..42edc2548 100644
--- a/src/lisp/lexer.cpp
+++ b/src/lisp/lexer.cpp
@@ -19,6 +19,7 @@
 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include <sstream>
 #include <stdexcept>
+#include <cstdio>
 #include <cstring>
 
 #include "lisp/lexer.hpp"