diff --git a/src/Lib/Polygon/polygon.cxx b/src/Lib/Polygon/polygon.cxx
index edc3cd29..a65499c6 100644
--- a/src/Lib/Polygon/polygon.cxx
+++ b/src/Lib/Polygon/polygon.cxx
@@ -35,6 +35,10 @@
 
 #include "polygon.hxx"
 
+#ifdef _MSC_VER
+#   define LONG_LONG_MAX LLONG_MAX
+#endif
+
 using std::endl;
 using std::cout;