[Bug c++/78890] [5/6/7 Regression] ICE on invalid reference type in union

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78890

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Sure, I just wanted to understand why the r211318 change has been done and my
comment lists why I think that happened.