Fix compiler warnings on VS 2015, refs #3439, refs #5069.

Patch By: Stan
Reviewed By: Itms, vladislavbelov
Differential Revision: https://code.wildfiregames.com/D1262
This was SVN commit r21480.

source/third_party/cppformat/format.cpp

@@ -61,11 +61,6 @@ using fmt::LongLong;
 using fmt::ULongLong;
 using fmt::internal::Arg;
 
-#ifdef _MSC_VER
-# pragma warning(push)
-# pragma warning(disable: 4127) // conditional expression is constant
-#endif
-
 namespace {
 
 #ifndef _MSC_VER
@@ -94,6 +89,12 @@ inline int isinfinity(long double x) { return std::isinf(x); }
 
 #else  // _MSC_VER
 
+# pragma warning(push)
+# pragma warning(disable: 4127) // conditional expression is constant
+#if _MSC_VER > 1800
+# pragma warning(disable:4456) // hides previous local declaration
+#endif
+
 inline int getsign(double value) {
   if (value < 0) return 1;
   if (value == value) return 0;