[Bug c++/83921] [7/8 Regression] GCC rejects constexpr initialization of empty aggregate.

[eric at efcs dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83921

--- Comment #3 from Eric Fiselier <eric at efcs dot ca> ---
The problem also reproduces when the empty type has an explicitly defaulted
default constructor. Example:

struct Foo { Foo() = default; };
constexpr void test() { Foo f; };