fix compilation warning.
diff --git a/tinyxml2.h b/tinyxml2.h
index 605a1ca..615afa5 100755
--- a/tinyxml2.h
+++ b/tinyxml2.h
@@ -2034,7 +2034,7 @@
     }

 

 protected:

-	virtual bool CompactMode( const XMLElement& elem )	{ return _compactMode; };

+	virtual bool CompactMode( const XMLElement& )	{ return _compactMode; };

 

 	/** Prints out the space before an element. You may override to change

 	    the space and tabs used. A PrintSpace() override should call Print().