[Bug c++/95305] Same code takes ~1/4 to 1/7th the time to compile under clang++.

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95305

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Created attachment 48621
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48621&action=edit
preprocessed source

Compile with -std=gnu++17