https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127395
--- Comment #4 from Iain Sandoe <iains at gcc dot gnu.org> --- so, it seems that in cxx_eval_constant_expression() we intend to handle CONSTRUCTORS that are TREE_CONSTANT [ours is], but we also require reduced_constant_expression_p () to be true and that returns false for any CONSTRUCTOR that is not an aggregate type (which ours is not [since it's a bare int]). I am not sure what the right fix here would be - to match the combined intents.
