Re: pure virttual function

From:

"Alf P. Steinbach" <alfps@start.no>

Newsgroups:

comp.lang.c++

Date:

Wed, 05 Jul 2006 22:19:13 +0200

Message-ID:

<4h2l66F1p83rlU1@individual.net>

* Alf P. Steinbach:

  struct Oops
  {
      Oops() { g(); } // <-- Call of pure virtual function
      virtual void g() = 0;
  };

  void Oops::g() {}

For any quality compiler you're guaranteed that the code fails to
compile or else that the call g() is implemented as a virtual call (then
resulting in a call of a function that issues a run-time diagnostic), in
spite of the dynamic type of the object being known.

Except MSVC 7.1... :-(

g++ refuses to compile the code, Comeau warns, MSVC 7.1 happily compiles
it with no diagnostic (!) and calls the Oops::g() implementation.

Did I just say that MSVC 7.1 is not a quality compiler? Seems so.
Since I've maintained the opposite on numerous occasions I have hereby
contradicted myself -- what would life be without contradictions?

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