[Bug c++/79369] New: namespace definition with qualified id

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79369

            Bug ID: 79369
           Summary: namespace definition with qualified id
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nathan at gcc dot gnu.org
  Target Milestone: ---

namespaces are magically conjured up if you use a qualified name:

namespace X::Y::Z 
{
}

X::Y must already be a namespace, but we don't complain.

Also, we do the strong using dance on reopenings of a inline namespace.  We
only need to do it on creation.