[Bug c++/126922] internal compiler error when initializing a struct of std::meta::info

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126922

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Now, build_zero_cst doesn't even build -1s for null pointer-to-data-member
elements, so perhaps we should just special case there reflection and nothing
else.