this file should be compilable in C

diff --git a/include/simgrid/s4u/mailbox.hpp b/include/simgrid/s4u/mailbox.hpp
index 4ee1d81..387f63b 100644 (file)
--- a/include/simgrid/s4u/mailbox.hpp
+++ b/include/simgrid/s4u/mailbox.hpp
@@ -2,15 +2,16 @@
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
-#ifdef __cplusplus
 
 #ifndef SIMGRID_S4U_MAILBOX_HPP
 #define SIMGRID_S4U_MAILBOX_HPP
 
-#include <boost/unordered_map.hpp>
-
 #include <xbt/base.h>
 #include <simgrid/s4u/forward.hpp>
+
+#ifdef __cplusplus
+
+# include <boost/unordered_map.hpp>
 #include <simgrid/s4u/actor.hpp>
 
 namespace simgrid {