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Date: Fri, 22 Feb 2008 17:41:00 -0000
Subject: [Bug c++/35297]  New: Compiling error with variadic template with fixed parameter with default type.
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From: "rodolfo at rodsoft dot org" <gcc-bugzilla@gcc.gnu.org>
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Hi,
the following code fails to compile with gcc-4.3-20080215

template <class T=int, class... ARGS> 
struct test {};

int main()
{
        test<> a;
        return 0;
}

According to N2242 section 3.6, page 7:

If a template-parameter of a class template has a default template-argument,
each subsequent template-parameter shall either have a default
template-argument supplied or be a template parameter pack. If a
template-parameter of a class template is a template parameter pack, it must be
the last template-parameter. 

The compiler issues the following error: no default argument for ‘ARGS’  at
line 1 above.


-- 
           Summary: Compiling error with variadic template with fixed
                    parameter with default type.
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rodolfo at rodsoft dot org
 GCC build triplet: *-*-*-*
  GCC host triplet: *-*-*-*
GCC target triplet: *-*-*-*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35297