[Bug c++/99809] ICE: sorry, unimplemented: unexpected AST of kind nontype_argument_pack

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99809

--- Comment #2 from 康桓瑋 <hewillk at gmail dot com> ---
I think this is not a valid code even if clang accepts it, since the parameter
packs args are not expanded.