[Bug c++/59937] [constexpr] bogus diagnostic "used in its own initializer"

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59937

--- Comment #5 from Paolo Carlini <paolo.carlini at oracle dot com> ---
This is fixed for 5.0. I'm adding the testcases and closing the bug.