go/test/blank1.go
Rémy Oudompheng 428ea6865c cmd/gc: fix computation of equality class of types.
A struct with a single field was considered as equivalent to the
field type, which is incorrect is the field is blank.

Fields with padding could make the compiler think some
types are comparable when they are not.

Fixes #5698.

R=rsc, golang-dev, daniel.morsing, bradfitz, gri, r
CC=golang-dev
https://golang.org/cl/10271046
2013-07-02 09:08:43 +02:00

29 lines
599 B
Go

// errorcheck
// 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 incorrect uses of the blank identifer are caught.
// Does not compile.
package _ // ERROR "invalid package name _"
var t struct {
_ int
}
type T struct {
_ []int
}
func main() {
_() // ERROR "cannot use _ as value"
x := _+1 // ERROR "cannot use _ as value"
_ = x
_ = t._ // ERROR "cannot refer to blank field"
var v1, v2 T
_ = v1 == v2 // ERROR "cannot be compared|non-comparable"
}