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

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

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Testcase without headers:
struct A {
  decltype (^^::) a, b;
};

template <A>
consteval void foo () {}

int
main ()
{
  foo <A { .b = {}}> ();
}

We ICE in
3890                                    if (abi_check (21))
3891                                      write_expression (build_zero_cst
3892                                                        (TREE_TYPE
(field)));
because build_zero_cst, which is defined in generic part of the compiler,
doesn't properly handle META_TYPE (which is FE specific).
Now, we could call instead of build_zero_cst (type) build_zero_init (type,
NULL_TREE, false), or do so only for scalar types and keep using build_zero_cst
otherwise, ...