[Bug c++/68821] New: g++ does not warn/error when virtual function return type is different than the one it overrides

[bobby.prani at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68821

            Bug ID: 68821
           Summary: g++ does not warn/error when virtual function return
                    type is different than the one it overrides
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bobby.prani at gmail dot com
  Target Milestone: ---

Consider:

typedef void (*obj_t)(void);

class parent {
  public:

    struct obj_base {
      virtual ~obj_base() {}
      virtual void operator()(void)=0;
    };

    template <typename T> struct obj : public obj_base {
      typedef void (T::*obj_t)(void);
      T* p; obj_t f;
      obj(T* p, obj_t f) : p(p), f(f) {}
      int *operator()(void) {
        return 0;
      }
    };
};

The overridden function has a different return type in the two cases. g++ does
not warn/error out about this.