Apply a fix from DoDoEnt for 64 bit linux systems where var args would crash
diff --git a/tinyxml2.cpp b/tinyxml2.cpp
index ff974ec..68b8fa8 100644
--- a/tinyxml2.cpp
+++ b/tinyxml2.cpp
@@ -1523,6 +1523,9 @@
 			memcpy( p, accumulator.Mem(), len+1 );

 		#else

 			int len = vsnprintf( 0, 0, format, va );

+			// Close out and re-start the va-args

+			va_end( va );

+			va_start( va, format );		

 			char* p = buffer.PushArr( len ) - 1;

 			vsnprintf( p, len+1, format, va );

 		#endif