//ww:error "structural fallback cannot disambiguate nominally-distinct same-shape variants"
// 925_nested_union_widen collision_guard: two distinct names a,b both !(i32|bool)
// in one union (a | b) — without nominal layout the widen cannot pick a variant.
// BOTH stages must loud-stop (runww ERROR arm runs w6c AND w6c_ww). Migrated from
// 989-era 925_nested_union_widen_run.c (#5-C5).
package main;
type a = !(i32 | bool);
type b = !(i32 | bool);
export fn main() i32 = {
	let x: a = (1i32: a);
	let r: (a | b) = x;
	match (r) {
	case let p: a => return 1;
	case let q: b => return 2;
	};
};