[Bug c++/82947] Variadic `using` directive incorrectly compiled without base classes (with class template argument deduction)

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82947

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
In GCC 11+ we get:
<source>: In instantiation of 'struct foo<main()::<lambda()> >':
<source>:16:19:   required from here
<source>:8:29: error: type 'main()::<lambda()>' is not a base type for type
'foo<main()::<lambda()> >'
    8 |         using Ts::operator()...;
      |                             ^~~