https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125498
--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
And that's because we've thrown away the body of S::S(int) in
cgraph_node::release_body:
if (!keep_arguments)
DECL_ARGUMENTS (decl) = NULL;
so now we have no DECL_ARGUMENTS, and then we do write_reflection on S::S(int).
