[Bug c++/106221] lamba inside a decltype in a using statement does not always work

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106221

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.5                        |---
            Summary|[10/11/12/13 Regression]    |lamba inside a decltype in
                   |cannot compile variadic     |a using statement does not
                   |arguments with a concept as |always work
                   |the variadic type in a      |
                   |namespace                   |

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Even more reduced:
namespace
{
    using T = decltype([](){});
}

template<typename Opts>
using foo = T;

using bar = foo<int>;