diff --git a/tinyxml2.cpp b/tinyxml2.cpp
index 510de38..a6ec20a 100755
--- a/tinyxml2.cpp
+++ b/tinyxml2.cpp
@@ -1684,7 +1684,7 @@ XMLError XMLDocument::Parse( const char* p, size_t len )
         return _errorID;
     }
 
-	int delta = p - start;	// skip initial whitespace, BOM, etc.
+    ptrdiff_t delta = p - start;	// skip initial whitespace, BOM, etc.
     ParseDeep( _charBuffer+delta, 0 );
     return _errorID;
 }