mirror of
https://github.com/golang/go
synced 2024-11-05 17:36:15 -07:00
a069cf048d
Before, an unnamed return value turned into an ONAME node n with n->sym named ~anon%d, and n->orig == n. A blank-named return value turned into an ONAME node n with n->sym named ~anon%d but n->orig == the original blank n. Code generation and printing uses n->orig, so that this node formatted as _. But some code does not use n->orig. In particular the liveness code does not know about the n->orig convention and so mishandles blank identifiers. It is possible to fix but seemed better to avoid the confusion entirely. Now the first kind of node is named ~r%d and the second ~b%d; both have n->orig == n, so that it doesn't matter whether code uses n or n->orig. After this change the ->orig field is only used for other kinds of expressions, not for ONAME nodes. This requires distinguishing ~b from ~r names in a few places that care. It fixes a liveness analysis bug without actually changing the liveness code. TBR=ken2 CC=golang-codereviews https://golang.org/cl/63630043
152 lines
3.4 KiB
Go
152 lines
3.4 KiB
Go
// errorcheck -0 -m -l
|
|
|
|
// Copyright 2012 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, using compiler diagnostic flags, that the escape analysis is working.
|
|
// Compiles but does not run. Inlining is disabled.
|
|
|
|
package foo
|
|
|
|
func noleak(p *int) int { // ERROR "p does not escape"
|
|
return *p
|
|
}
|
|
|
|
func leaktoret(p *int) *int { // ERROR "leaking param: p to result"
|
|
return p
|
|
}
|
|
|
|
func leaktoret2(p *int) (*int, *int) { // ERROR "leaking param: p to result ~r1" "leaking param: p to result ~r2"
|
|
return p, p
|
|
}
|
|
|
|
func leaktoret22(p, q *int) (*int, *int) { // ERROR "leaking param: p to result ~r2" "leaking param: q to result ~r3"
|
|
return p, q
|
|
}
|
|
|
|
func leaktoret22b(p, q *int) (*int, *int) { // ERROR "leaking param: p to result ~r3" "leaking param: q to result ~r2"
|
|
return leaktoret22(q, p)
|
|
}
|
|
|
|
func leaktoret22c(p, q *int) (*int, *int) { // ERROR "leaking param: p to result ~r3" "leaking param: q to result ~r2"
|
|
r, s := leaktoret22(q, p)
|
|
return r, s
|
|
}
|
|
|
|
func leaktoret22d(p, q *int) (r, s *int) { // ERROR "leaking param: p to result s" "leaking param: q to result r"
|
|
r, s = leaktoret22(q, p)
|
|
return
|
|
}
|
|
|
|
func leaktoret22e(p, q *int) (r, s *int) { // ERROR "leaking param: p to result s" "leaking param: q to result r"
|
|
r, s = leaktoret22(q, p)
|
|
return r, s
|
|
}
|
|
|
|
func leaktoret22f(p, q *int) (r, s *int) { // ERROR "leaking param: p to result s" "leaking param: q to result r"
|
|
rr, ss := leaktoret22(q, p)
|
|
return rr, ss
|
|
}
|
|
|
|
var gp *int
|
|
|
|
func leaktosink(p *int) *int { // ERROR "leaking param: p"
|
|
gp = p
|
|
return p
|
|
}
|
|
|
|
func f1() {
|
|
var x int
|
|
p := noleak(&x) // ERROR "&x does not escape"
|
|
_ = p
|
|
}
|
|
|
|
func f2() {
|
|
var x int
|
|
p := leaktoret(&x) // ERROR "&x does not escape"
|
|
_ = p
|
|
}
|
|
|
|
func f3() {
|
|
var x int // ERROR "moved to heap: x"
|
|
p := leaktoret(&x) // ERROR "&x escapes to heap"
|
|
gp = p
|
|
}
|
|
|
|
func f4() {
|
|
var x int // ERROR "moved to heap: x"
|
|
p, q := leaktoret2(&x) // ERROR "&x escapes to heap"
|
|
gp = p
|
|
gp = q
|
|
}
|
|
|
|
func f5() {
|
|
var x int
|
|
leaktoret22(leaktoret2(&x)) // ERROR "&x does not escape"
|
|
}
|
|
|
|
func f6() {
|
|
var x int // ERROR "moved to heap: x"
|
|
px1, px2 := leaktoret22(leaktoret2(&x)) // ERROR "&x escapes to heap"
|
|
gp = px1
|
|
_ = px2
|
|
}
|
|
|
|
type T struct{ x int }
|
|
|
|
func (t *T) Foo(u int) (*T, bool) { // ERROR "leaking param: t to result"
|
|
t.x += u
|
|
return t, true
|
|
}
|
|
|
|
func f7() *T {
|
|
r, _ := new(T).Foo(42) // ERROR "new.T. escapes to heap"
|
|
return r
|
|
}
|
|
|
|
func leakrecursive1(p, q *int) (*int, *int) { // ERROR "leaking param: p" "leaking param: q"
|
|
return leakrecursive2(q, p)
|
|
}
|
|
|
|
func leakrecursive2(p, q *int) (*int, *int) { // ERROR "leaking param: p" "leaking param: q"
|
|
if *p > *q {
|
|
return leakrecursive1(q, p)
|
|
}
|
|
// without this, leakrecursive? are safe for p and q, b/c in fact their graph does not have leaking edges.
|
|
return p, q
|
|
}
|
|
|
|
|
|
var global interface{}
|
|
|
|
type T1 struct {
|
|
X *int
|
|
}
|
|
|
|
type T2 struct {
|
|
Y *T1
|
|
}
|
|
|
|
func f8(p *T1) (k T2) { // ERROR "leaking param: p to result k" "leaking param: p"
|
|
if p == nil {
|
|
k = T2{}
|
|
return
|
|
}
|
|
|
|
global = p // should make p leak always
|
|
return T2{p}
|
|
}
|
|
|
|
func f9() {
|
|
var j T1 // ERROR "moved to heap: j"
|
|
f8(&j) // ERROR "&j escapes to heap"
|
|
}
|
|
|
|
func f10() {
|
|
// These don't escape but are too big for the stack
|
|
var x [1<<30]byte // ERROR "moved to heap: x"
|
|
var y = make([]byte, 1<<30) // ERROR "does not escape"
|
|
_ = x[0] + y[0]
|
|
}
|