mirror of
https://github.com/golang/go
synced 2024-11-27 05:41:25 -07:00
744ebfde04
This is a crude compiler pass to eliminate stores to auto variables
that are only ever written to.
Eliminates an unnecessary store to x from the following code:
func f() int {
var x := 1
return *(&x)
}
Fixes #19765.
Change-Id: If2c63a8ae67b8c590b6e0cc98a9610939a3eeffa
Reviewed-on: https://go-review.googlesource.com/38746
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
43 lines
1.1 KiB
Go
43 lines
1.1 KiB
Go
// errorcheck -0 -live -wb=0
|
|
|
|
// Copyright 2014 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.
|
|
|
|
// liveness tests with inlining ENABLED
|
|
// see also live.go.
|
|
|
|
package main
|
|
|
|
// issue 8142: lost 'addrtaken' bit on inlined variables.
|
|
// no inlining in this test, so just checking that non-inlined works.
|
|
|
|
func printnl()
|
|
|
|
//go:noescape
|
|
func useT40(*T40)
|
|
|
|
type T40 struct {
|
|
m map[int]int
|
|
}
|
|
|
|
func newT40() *T40 {
|
|
ret := T40{}
|
|
ret.m = make(map[int]int) // ERROR "live at call to makemap: &ret$"
|
|
return &ret
|
|
}
|
|
|
|
func bad40() {
|
|
t := newT40() // ERROR "live at call to makemap: .autotmp_[0-9]+ ret$"
|
|
printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+ ret$"
|
|
useT40(t) // ERROR "live at call to useT40: .autotmp_[0-9]+ ret$"
|
|
}
|
|
|
|
func good40() {
|
|
ret := T40{}
|
|
ret.m = make(map[int]int) // ERROR "live at call to makemap: .autotmp_[0-9]+ ret$"
|
|
t := &ret
|
|
printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+ ret$"
|
|
useT40(t) // ERROR "live at call to useT40: .autotmp_[0-9]+ ret$"
|
|
}
|