mirror of
https://github.com/golang/go
synced 2024-10-06 08:00:07 +00:00
91b1f7cb15
Any initialization of a variable by a block copy or block zeroing or by multiple assignments (componentwise copying or zeroing of a multiword variable) needs to emit a VARDEF. These cases were not. Fixes #7205. TBR=iant CC=golang-codereviews https://golang.org/cl/63650044
116 lines
2.3 KiB
Go
116 lines
2.3 KiB
Go
// errorcheck -0 -l -live
|
|
|
|
// 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.
|
|
|
|
package main
|
|
|
|
func f1() {
|
|
var x *int
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
}
|
|
|
|
func f2(b bool) {
|
|
if b {
|
|
print(0) // nothing live here
|
|
return
|
|
}
|
|
var x *int
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
}
|
|
|
|
func f3(b bool) {
|
|
print(0)
|
|
if b == false {
|
|
print(0) // nothing live here
|
|
return
|
|
}
|
|
|
|
if b {
|
|
var x *int
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
print(&x) // ERROR "live at call to printpointer: x$"
|
|
} else {
|
|
var y *int
|
|
print(&y) // ERROR "live at call to printpointer: y$"
|
|
print(&y) // ERROR "live at call to printpointer: y$"
|
|
}
|
|
print(0) // ERROR "live at call to printint: x y$"
|
|
}
|
|
|
|
// The old algorithm treated x as live on all code that
|
|
// could flow to a return statement, so it included the
|
|
// function entry and code above the declaration of x
|
|
// but would not include an indirect use of x in an infinite loop.
|
|
// Check that these cases are handled correctly.
|
|
|
|
func f4(b1, b2 bool) { // x not live here
|
|
if b2 {
|
|
print(0) // x not live here
|
|
return
|
|
}
|
|
var z **int
|
|
x := new(int)
|
|
*x = 42
|
|
z = &x
|
|
print(**z) // ERROR "live at call to printint: x z$"
|
|
if b2 {
|
|
print(1) // ERROR "live at call to printint: x$"
|
|
return
|
|
}
|
|
for {
|
|
print(**z) // ERROR "live at call to printint: x z$"
|
|
}
|
|
}
|
|
|
|
func f5(b1 bool) {
|
|
var z **int
|
|
if b1 {
|
|
x := new(int)
|
|
*x = 42
|
|
z = &x
|
|
} else {
|
|
y := new(int)
|
|
*y = 54
|
|
z = &y
|
|
}
|
|
print(**z) // ERROR "live at call to printint: x y$"
|
|
}
|
|
|
|
// confusion about the _ result used to cause spurious "live at entry to f6: _".
|
|
|
|
func f6() (_, y string) {
|
|
y = "hello"
|
|
return
|
|
}
|
|
|
|
// confusion about addressed results used to cause "live at entry to f7: x".
|
|
|
|
func f7() (x string) {
|
|
_ = &x
|
|
x = "hello"
|
|
return
|
|
}
|
|
|
|
// ignoring block returns used to cause "live at entry to f8: x, y".
|
|
|
|
func f8() (x, y string) {
|
|
return g8()
|
|
}
|
|
|
|
func g8() (string, string)
|
|
|
|
// ignoring block assignments used to cause "live at entry to f9: x"
|
|
// issue 7205
|
|
|
|
var i9 interface{}
|
|
|
|
func f9() bool {
|
|
g8()
|
|
x := i9
|
|
return x != 99
|
|
}
|