[Bug c++/11077] New: enumerator value in template not assignable from bool

[numerical.simulation@web.de]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11077

           Summary: enumerator value in template not assignable from bool
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Severity: blocker
          Priority: P2
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: numerical.simulation@web.de
                CC: gcc-bugs@gcc.gnu.org,numerical.simulation@web.de
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

The following code does not compile with gcc, though it is valid C++ (IMHO)

#include <iostream>

template<class T> 
class has_member_disambiguation // Thanks to Paul Mensonides
{
protected:
  template<class U> static char check(typename U::Disambiguation*);
  template<class U> static char (& check(...))[2];

public:
  enum { value = (sizeof(check<T>(0)) == 1) };
};

struct A 
{
  typedef double Disambiguation;
};

struct B {};


int main()
{
  std::cerr << has_member_disambiguation<A>::value << std::endl;
  std::cerr << has_member_disambiguation<B>::value << std::endl;
}


g++ ~/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C: In instantiation of
`has_member_disambiguation<A>':
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:24:   instantiated from
here
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:11: error: invalid use of 
   undefined type `class has_member_disambiguation<A>'
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:5: error: declaration of `
   class has_member_disambiguation<A>'
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:11: error: enumerator 
   value for `value' not integer constant
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C: In instantiation of
`has_member_disambiguation<B>':
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:25:   instantiated from
here
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:11: error: invalid use of 
   undefined type `class has_member_disambiguation<B>'
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:5: error: declaration of `
   class has_member_disambiguation<B>'
/home/markus/hp-home/C++/EXPERIMENTAL/GCC-3.4-Bugs.C:11: error: enumerator 
   value for `value' not integer constant



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