Fix for issue #3541: Normalize xDir vector for Hole feature to correct hole diameter.

src/Mod/PartDesign/App/FeatureHole.cpp

@@ -985,6 +985,9 @@ App::DocumentObjectExecReturn *Hole::execute(void)
         else
             xDir = gp_Vec(0, -zDir.Z(), zDir.Y());
 
+        // Normalize xDir; this is needed as the computation above does not necessarily give a unit-length vector.
+        xDir.Normalize();
+
         if ( method == "Dimension" )
             length = Depth.getValue();
         else if ( method == "UpToFirst" ) {