[Bug c++/50108] New: [C++0x] Variadic templates with both type and non-type parameters

[Bug c++/50108] New: [C++0x] Variadic templates with both type and non-type parameters

[edward.schere@trash-mail.com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50108

             Bug #: 50108
           Summary: [C++0x] Variadic templates with both type and non-type
                    parameters
    Classification: Unclassified
           Product: gcc
           Version: 4.6.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: edward.schere@trash-mail.com


I'm not quite sure if this is a GCC bug, because the current C++ draft version
is unclear about this. I found neither an example that this code is ill-formed,
nor did I found an example that it's ok:


template<int... Ints, typename... Types>
class test_template
{
};

int main()
{
    test_template<1,2,3,int,double> tt;
    return 0;
}


GCC 4.6.1 rejects this code with the error "parameter pack 'Ints' must be at
the end of the template parameter list".

I guess the code is well-formed, because it is unambiguous and (semantically)
identical with the following code (that works fine in GCC):


template<int Int0, typename... Types>
class test_template
{
};

template<int Int0, int Int1, typename... Types>
class test_template
{
};

template<int Int0, int Int1, int Int2, typename... Types>
class test_template
{
};

[Bug c++/50108] [C++0x] Variadic templates with both type and non-type parameters

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50108

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-08-17 14:58:18 UTC ---
14.1 [temp.param] paragraph 11:
"If a template-parameter of a primary class template or alias template is a
template parameter pack, it shall be the last template-parameter."

[Bug c++/50108] [C++0x] Variadic templates with both type and non-type parameters

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50108

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID

--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-09-23 11:03:05 UTC ---
Invalid then.