[Bug c++/80605] [7/8 Regression] Bad is_standard_layout result with empty base classes

[ed at catmur dot co.uk]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80605

--- Comment #8 from Ed Catmur <ed at catmur dot co.uk> ---
Looks to have been fixed by r247816.