--- src/Savegame/CraftWeapon.cpp.orig	2014-06-13 19:14:43 UTC
+++ src/Savegame/CraftWeapon.cpp
@@ -16,6 +16,7 @@
  * You should have received a copy of the GNU General Public License
  * along with OpenXcom.  If not, see <http://www.gnu.org/licenses/>.
  */
+#include <cmath>
 #include "CraftWeapon.h"
 #include "../Ruleset/RuleCraftWeapon.h"
 #include "../Ruleset/Ruleset.h"
