mirror of
https://github.com/golang/go
synced 2024-11-24 18:20:02 -07:00
e24977d231
The next CL will remove the -G flag, effectively hard-coding it to its current default (-G=3). Change-Id: Ib4743b529206928f9f1cca9fdb19989728327831 Reviewed-on: https://go-review.googlesource.com/c/go/+/388534 Reviewed-by: Keith Randall <khr@golang.org> Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gopher Robot <gobot@golang.org>
48 lines
687 B
Go
48 lines
687 B
Go
// run
|
|
|
|
// Copyright 2021 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[T any] interface {
|
|
foo()
|
|
}
|
|
|
|
type J[T any] interface {
|
|
foo()
|
|
bar()
|
|
}
|
|
|
|
//go:noinline
|
|
func f[T J[T]](x T, g func(T) T) I[T] {
|
|
// contains a cast between two nonempty interfaces
|
|
// Also make sure we don't evaluate g(x) twice.
|
|
return I[T](J[T](g(x)))
|
|
}
|
|
|
|
type S struct {
|
|
x int
|
|
}
|
|
|
|
func (s *S) foo() {}
|
|
func (s *S) bar() {}
|
|
|
|
var cnt int
|
|
|
|
func inc(s *S) *S {
|
|
cnt++
|
|
return s
|
|
}
|
|
|
|
func main() {
|
|
i := f(&S{x: 7}, inc)
|
|
if i.(*S).x != 7 {
|
|
panic("bad")
|
|
}
|
|
if cnt != 1 {
|
|
panic("multiple calls")
|
|
}
|
|
}
|