}
	return false
}

// hasNil reports whether type t includes the nil value.
func hasNil(t Type) bool {
	switch u := under(t).(type) {
	case *Basic:
		return u.kind == UnsafePointer
	case *Slice, *Pointer, *Signature, *Map, *Chan:
		return true
	case *Interface:
		return !isTypeParam(t) || u.typeSet().underIs(func(u Type) bool {
			return u != nil && hasNil(u)
		})
	}
	return false
}

	}
	return false
}

// hasNil reports whether type t includes the nil value.
func hasNil(t Type) bool {
	switch u := under(t).(type) {
	case *Basic:
		return u.kind == UnsafePointer
	case *Slice, *Pointer, *Signature, *Map, *Chan:
		return true
	case *Interface:
		return !isTypeParam(t) || u.typeSet().underIs(func(u Type) bool {
			return u != nil && hasNil(u)
		})
	}
	return false
}

			// By checking assignment of x to an invisible temporary
			// (as a compiler would), we get all the relevant checks.
			check.assignment(&x, nil, "switch expression")
			if x.mode != invalid && !Comparable(x.typ) && !hasNil(x.typ) {
				check.errorf(&x, InvalidExprSwitch, "cannot switch on %s (%s is not comparable)", &x, x.typ)
				x.mode = invalid
			}
		} else {
			// spec: "A missing switch expression is

		// By checking assignment of x to an invisible temporary
		// (as a compiler would), we get all the relevant checks.
		check.assignment(&x, nil, "switch expression")
		if x.mode != invalid && !Comparable(x.typ) && !hasNil(x.typ) {
			check.errorf(&x, InvalidExprSwitch, "cannot switch on %s (%s is not comparable)", &x, x.typ)
			x.mode = invalid
		}
	} else {
		// spec: "A missing switch expression is