PartDesign: fix crash when opening a file with a metric hole

Author: jffmichi

src/Mod/PartDesign/App/FeatureHole.cpp

@@ -1176,13 +1176,14 @@ std::optional<double> Hole::determineDiameter() const
             return std::nullopt;
         throw Base::IndexError("Thread size out of range");
     }
-    double diameter = threadDescription[threadType][threadSize].diameter;
-    double pitch = threadDescription[threadType][threadSize].pitch;
-    double clearance = 0.0;
 
     if (threadType == 0)
         return std::nullopt;
 
+    double diameter = threadDescription[threadType][threadSize].diameter;
+    double pitch = threadDescription[threadType][threadSize].pitch;
+    double clearance = 0.0;
+
     if (Threaded.getValue()) {
 
         if (ModelThread.getValue()) {