[Bug c++/104008] [11/12 Regression] New g++ folly compile error with gcc 11.x. Bisected to PR99445 c++: Alias template in pack expansion

[ahornby at fb dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104008

--- Comment #5 from Alex Hornby <ahornby at fb dot com> ---
(In reply to Alex Hornby from comment #3)
> Created attachment 52356 [details]
> preprocessed source from gcc 10.3.0

done, also captured the source from a failing 11.2.1 build at same system state