// errchk $G -e $D/$F.go

// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package main


type I interface {
       M()
}

func main(){
       var x I
       switch x.(type) {
       case string:	// ERROR "impossible"
               println("FAIL")
       }
}