(freebsd) compilation fix microsoft#1

AnyCPU · AnyCPU · commit e4de34515642 · 2015-12-22T22:10:08.000Z
diff --git a/Release/include/pplx/pplxcancellation_token.h b/Release/include/pplx/pplxcancellation_token.h
@@ -34,6 +34,7 @@
 #error This file must not be included for Visual Studio 12 or later
 #endif
 
+#include <cstdlib>
 #include <string>
 #include "pplx/pplxinterface.h"
 
