[Bug c++/127316] [reflection] ICE redeclaring a function whose return type involves a reflection of a parameter variable

[ensadc at mailnesia dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127316

--- Comment #6 from ensadc at mailnesia dot com ---
Fortunately, `auto f(int a) -> constant_wrapper<^^f>;` is invalid because `f`
is not visible in its own declarator.