code review 10255047: cmd/gc: don't attempt to generate wrappers for blank in...

test/interface/fail.go

 // run
 
 // Copyright 2009 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.
 
 // Test that interface conversion fails when method is missing.
 
 package main
 
 type I interface {
         Foo()
 }
 
 func main() {
         shouldPanic(p1)
+        shouldPanic(p2)
 }
 
 func p1() {
         var s *S
         var i I
-        var e interface {}
+        var e interface{}
         e = s
         i = e.(I)
         _ = i
 }
 
-type S struct {
+type S struct{}
+
+func (s *S) _() {}
+
+type B interface {
+        _()
+}
+
+func p2() {
+        var s *S
+        var b B
+        var e interface{}
+        e = s
+        b = e.(B)
+        _ = b
 }
 
 func shouldPanic(f func()) {
         defer func() {
                 if recover() == nil {
                         panic("function should panic")
                 }
         }()
         f()
 }