[Bug c++/54537] New: undiagnosed using-declaration conflicting with used function

[fabien at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54537

             Bug #: 54537
           Summary: undiagnosed using-declaration conflicting with used
                    function
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: fab...@gcc.gnu.org


Noticed while working on DR39, the below is wrongly accepted. A diagnostic is
issued if the function f is not used.

namespace a
{
  void f(int);
}

namespace b
{
  void f(int);
  void g()
  {
    f (3);
  }
  using a::f; // { dg-error "already declared" }
}

I have a patch for it.