diff --git a/include/cxxopts.hpp b/include/cxxopts.hpp
index 088c7a5..3dd5f52 100644
--- a/include/cxxopts.hpp
+++ b/include/cxxopts.hpp
@@ -25,8 +25,8 @@ THE SOFTWARE.
 #ifndef CXXOPTS_HPP_INCLUDED
 #define CXXOPTS_HPP_INCLUDED
 
-#include <cstring>
 #include <cctype>
+#include <cstring>
 #include <exception>
 #include <iostream>
 #include <limits>