[Bug c++/14821] New: [3.4/3.5 Regression] Duplicate namespace alias declaration should not conflict

["giovannibajo at libero dot it" <gcc-bugzilla at gcc dot gnu dot org>]

-----------------------------------
namespace A {
  namespace B {}
}

namespace A {
  namespace Alias = ::A::B;
}

namespace A {
  namespace Alias = ::A::B;
}
-----------------------------------
namespace.cc:10: error: declaration of `namespace Alias = A::B;'
namespace.cc:6: error: conflicts with previous declaration `namespace Alias = A:
:B;'


This is obviously bogus, and breaks a library currently under review for Boost. 
The workaround is harder than one might think because the conflicting aliases 
come from different headers.

-- 
           Summary: [3.4/3.5 Regression] Duplicate namespace alias
                    declaration should not conflict
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: giovannibajo at libero dot it
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14821