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[Bug c++/40055] New: Failing instantiation of template with enums


The  following code failed with the message (no options are given to the
compiler): 

instance.cc: In function 'int main()':
instance.cc:30: error: no matching function for call to 'c_struct<a_tags,
a_struct>::c_struct(a0_type&)'
instance.cc:14: note: candidates are: c_struct<a_tags,
a_struct>::c_struct(const c_struct<a_tags, a_struct>&)

---------------------------------------

enum a_tags { A0, A1 };
enum b_tags { B0, B1 };

template < a_tags Tag >
struct a_struct
{};

template < b_tags Tag >
struct b_struct
{};

template < typename tags, template < tags > class Element >
struct c_struct
{
  template < tags Tag >
  c_struct(Element< Tag >)
  {}
};

typedef c_struct< a_tags, a_struct > a_type;
typedef c_struct< b_tags, b_struct > b_type;
typedef a_struct< A0 > a0_type;
typedef b_struct< B0 > b0_type;

int main()
{
  a0_type a0;
  b0_type b0;
  b_type b_instance(b0);
  a_type a_instance(a0);
}

------------------------------

But if one of the line:
    b_type b_instance(b0);
    a_type a_instance(a0);
is commented out, then the compilation succeeds.

---------------------------
My g++ version, although I've been able to reproduce this bug with older
versions of gcc:
% /usr/local/env/gcc-4.4.0/bin/g++ -v 
Using built-in specs.
Target: i386-apple-darwin9.6.0
Configured with: ../gcc-4.4.0/configure --prefix=/usr/local/env/gcc-4.4.0
--disable-nls --enable-languages=c,c++
Thread model: posix
gcc version 4.4.0 (GCC)


-- 
           Summary: Failing instantiation of template with enums
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: alexandre dot hamez at gmail dot com
 GCC build triplet: i386-apple-darwin9.6.0
  GCC host triplet: i386-apple-darwin9.6.0
GCC target triplet: i386-apple-darwin9.6.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40055


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