blob: d6f07b30e2ffdb6eee2b83f44b100d3016fe39be [file] [log] [blame]
// run
// Copyright 2017 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.
// This test makes sure that itabs are unique.
// More explicitly, we require that only one itab structure exists for the pair of
// a given compile-time interface type and underlying concrete type.
// Ensuring this invariant enables fixes for 18492 (improve type switch code).
package main
type I interface {
M()
}
type J interface {
M()
}
type T struct{}
func (*T) M() {}
func main() {
test1()
test2()
}
func test1() {
t := new(T)
var i1, i2 I
var j interface {
M()
}
i1 = t
j = t
i2 = j
if i1 != i2 {
panic("interfaces not equal")
}
}
func test2() {
t := new(T)
i1 := (I)(t)
i2 := (I)((interface {
M()
})((J)(t)))
if i1 != i2 {
panic("interfaces not equal")
}
}