// #23 builtin carve-out — a user redecl of a pre-seeded builtin name is
// NOT a duplicate (cstage keeps no builtins in scope: lookup_builtin wins
// first at check.c:69, so the user version installs dead). wwstage seeds
// builtins into c.top, so installtop must DROP this redecl rather than
// erroring. Both stages accept; the builtin `nomem` (= !void) wins, so
// g()'s i32 arm returns 7. Pins the 771/774/926 shape.
type nomem = !void;
fn g() (i32 | nomem) = { return 7; };
export fn main() i32 = {
	match (g()) {
	case let v: i32 => return v;
	case nomem => return 99;
	};
};