diff --git a/src/help/help_impl.hpp b/src/help/help_impl.hpp
index a5d24910fc9..5bafadf5970 100644
--- a/src/help/help_impl.hpp
+++ b/src/help/help_impl.hpp
@@ -32,10 +32,10 @@
 #ifndef HELP_IMPL_INCLUDED
 #define HELP_IMPL_INCLUDED
 
-#include "config.hpp"
 #include "exceptions.hpp"               // for error
 #include "font.hpp"                     // for line_width, relative_size
 
+#include <cstring>
 #include <list>                         // for list
 #include <ostream>                      // for operator<<, stringstream, etc
 #include <string>                       // for string, allocator, etc
@@ -44,6 +44,7 @@
 #include <boost/shared_ptr.hpp>
 #include <SDL.h>                  // for SDL_Color, SDL_Surface
 
+class config;
 class unit_type;
 class terrain_type_data;
 typedef boost::shared_ptr<terrain_type_data> tdata_cache;