Re: [boost] utility/value_init.hpp: VC 7.1 ICE & workaround

From: Niels Dekker - mail address until 2008-12-31 (nd_mail_address_valid_until_2008-12-31_at_[hidden])
Date: 2007-09-15 17:22:11

Ralf W. Grosse-Kunstleve wrote:
> The SVN head of boost/utility/value_init.hpp produces a
> Visual C++ 7.1 ICE (see below) when compiling some of
> our Boost.Python extensions.

Thanks again!  I finally got a minimal example of how to reproduce the 
"INTERNAL COMPILER ERROR":

  ////////////////////////////////////////////////////////////
  #include <boost/utility/value_init.hpp>

  class Foo { };

  int main() {
    boost::value_initialized<Foo *> i;  // VC 7.1 ICE!!!
    return 0;
  }
  ////////////////////////////////////////////////////////////

MSVC 7.1 just doesn't seem to like "get().T::~T()" when T is a pointer 
to an instance of a class.  Apparently the bug was fixed with MSVC 8.0. 
BTW, MSVC 7.1 *does* accept "(&get())->T::~T()".  But anyway, the patch 
you suggested is fine to me as well.

> The simple patch below works around the problem.
> I've also tested with with VC 8.0. Is this OK to commit?

Please do!  :-)

BTW, Fernando Cacciola and I do have some ideas on how to further 
improve value_initialized, so I expect that your patch won't be needed 
anymore in the future.  But at the moment, your patch is still 
definitely necessary!

Kind regards, Niels