[Bug c++/86094] [8/9 Regression] Call ABI changed for small objects with defaulted ctor

[amonakov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86094

--- Comment #3 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
-fabi-version=12 is not documented, not mentioned in release notes, and not
wired up in -Wabi.