[Bug c++/54055] spurious(?) "invalid use of incomplete type" warning in template definition

["daniel.kruegler at googlemail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54055

Daniel KrÃgler <daniel.kruegler at googlemail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |daniel.kruegler at
                   |                            |googlemail dot com

--- Comment #1 from Daniel KrÃgler <daniel.kruegler at googlemail dot com> 2012-07-20 19:18:03 UTC ---
Your example can be reduced to the following model code:

template<typename T>
struct A
{
  struct B : A { };
};

I can assure you that you cannot rely on that. This example has recently been
raised to the committee and it was not 100% clear what the result should be. A
new core language issue will be opened for this. The problem is that some
arguments were brought pointing to the equivalent example

struct A
{
  struct B : A { };
};

being invalid since ages. There is no tendency to make the latter valid, but is
has to be clarified what the state of the first (your) example will be.