Fixes FreeCAD#14349: GeoFeature::getElementTypes causes undefined behaviour

Author: wwmayer

src/App/GeoFeature.cpp

@@ -268,7 +268,7 @@ const std::vector<std::string>& GeoFeature::searchElementCache(const std::string
     return none;
 }
 
-const std::vector<const char*>& GeoFeature::getElementTypes(bool /*all*/) const
+std::vector<const char*> GeoFeature::getElementTypes(bool /*all*/) const
 {
     static std::vector<const char*> nil;
     auto prop = getPropertyOfGeometry();

src/App/GeoFeature.h

@@ -177,7 +177,7 @@ class AppExport GeoFeature : public App::DocumentObject
     virtual DocumentObject *getElementOwner(const Data::MappedName & /*name*/) const
     {return nullptr;}
 
-    virtual const std::vector<const char *>& getElementTypes(bool all=true) const;
+    virtual std::vector<const char *> getElementTypes(bool all=true) const;
 
     /// Return the higher level element names of the given element
     virtual std::vector<Data::IndexedName> getHigherElements(const char *name, bool silent=false) const;