func init() {
	ch := make(chan int)
	select {
	case n, _ := <-ch:
		_ = n
	default:
	}
	type mybool bool
	var x int
	var y mybool
	select {
	case x, y = <-ch:
	default:
	}
	_ = x
	_ = y
}
Static tests of SSA builder (via the sanity checker).
Dynamic semantics are not exercised.
package main