[Bug c++/40942] New: GCC accepts code that Comeau and MSVC deems invalid.

["v dot haisman at sh dot cvut dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

The following test case compiles with GCC, it chooses the second ctor. Both
MSVC8 and Comeau reject it complaining about overload ambiguity.


#include <cstdlib>

template <bool B, class T = void>
struct enable_if_c {
  typedef T type;
};

template <class T>
struct enable_if_c<false, T> {};

template <class Cond, class T = void>
struct enable_if : public enable_if_c<Cond::value, T> {};


struct true_type
{
  enum { value = 1 };
};


struct false_type
{
  enum { value = 0 };
};


template <typename T, typename U>
struct is_same
  : public false_type
{ };


template <typename T>
struct is_same<T, T>
  : public true_type
{ };


struct S
{
  template <typename T>
  S (T const *,
     typename enable_if<is_same<char, T>, T *>::type = 0)
  { }

  template <size_t N>
  S (char const (&)[N])
  { }
};

int
main()
{
  char array[] = "test";

  S s1 ("test");
  S s2 (array);
}


-- 
           Summary: GCC accepts code that Comeau and MSVC deems invalid.
           Product: gcc
           Version: 4.4.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: v dot haisman at sh dot cvut dot cz
 GCC build triplet: x86_64-portbld-freebsd7.1
  GCC host triplet: x86_64-portbld-freebsd7.1
GCC target triplet: x86_64-portbld-freebsd7.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40942