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// errorcheck -0 -m -l
// Copyright 2015 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 escape analysis for interface conversions.
package escape
var sink interface{}
type M interface {
M()
}
func mescapes(m M) { // ERROR "leaking param: m"
sink = m
}
func mdoesnotescape(m M) { // ERROR "m does not escape"
}
// Tests for type stored directly in iface and with value receiver method.
type M0 struct {
p *int
}
func (M0) M() {
}
func efaceEscape0() {
{
i := 0
v := M0{&i}
var x M = v
_ = x
}
{
i := 0 // ERROR "moved to heap: i"
v := M0{&i}
var x M = v
sink = x
}
{
i := 0
v := M0{&i}
var x M = v
v1 := x.(M0)
_ = v1
}
{
i := 0 // ERROR "moved to heap: i"
v := M0{&i}
// BAD: v does not escape to heap here
var x M = v
v1 := x.(M0)
sink = v1
}
{
i := 0
v := M0{&i}
var x M = v
x.M() // ERROR "devirtualizing x.M"
}
{
i := 0 // ERROR "moved to heap: i"
v := M0{&i}
var x M = v
mescapes(x)
}
{
i := 0
v := M0{&i}
var x M = v
mdoesnotescape(x)
}
}
// Tests for type stored indirectly in iface and with value receiver method.
type M1 struct {
p *int
x int
}
func (M1) M() {
}
func efaceEscape1() {
{
i := 0
v := M1{&i, 0}
var x M = v // ERROR "v does not escape"
_ = x
}
{
i := 0 // ERROR "moved to heap: i"
v := M1{&i, 0}
var x M = v // ERROR "v escapes to heap"
sink = x
}
{
i := 0
v := M1{&i, 0}
var x M = v // ERROR "v does not escape"
v1 := x.(M1)
_ = v1
}
{
i := 0 // ERROR "moved to heap: i"
v := M1{&i, 0}
var x M = v // ERROR "v does not escape"
v1 := x.(M1)
sink = v1 // ERROR "v1 escapes to heap"
}
{
i := 0
v := M1{&i, 0}
var x M = v // ERROR "v does not escape"
x.M() // ERROR "devirtualizing x.M"
}
{
i := 0 // ERROR "moved to heap: i"
v := M1{&i, 0}
var x M = v // ERROR "v escapes to heap"
mescapes(x)
}
{
i := 0
v := M1{&i, 0}
var x M = v // ERROR "v does not escape"
mdoesnotescape(x)
}
}
// Tests for type stored directly in iface and with pointer receiver method.
type M2 struct {
p *int
}
func (*M2) M() {
}
func efaceEscape2() {
{
i := 0
v := &M2{&i} // ERROR "&M2{...} does not escape"
var x M = v
_ = x
}
{
i := 0 // ERROR "moved to heap: i"
v := &M2{&i} // ERROR "&M2{...} escapes to heap"
var x M = v
sink = x
}
{
i := 0
v := &M2{&i} // ERROR "&M2{...} does not escape"
var x M = v
v1 := x.(*M2)
_ = v1
}
{
i := 0 // ERROR "moved to heap: i"
v := &M2{&i} // ERROR "&M2{...} escapes to heap"
// BAD: v does not escape to heap here
var x M = v
v1 := x.(*M2)
sink = v1
}
{
i := 0 // ERROR "moved to heap: i"
v := &M2{&i} // ERROR "&M2{...} does not escape"
// BAD: v does not escape to heap here
var x M = v
v1 := x.(*M2)
sink = *v1
}
{
i := 0 // ERROR "moved to heap: i"
v := &M2{&i} // ERROR "&M2{...} does not escape"
// BAD: v does not escape to heap here
var x M = v
v1, ok := x.(*M2)
sink = *v1
_ = ok
}
{
i := 0
v := &M2{&i} // ERROR "&M2{...} does not escape"
var x M = v
x.M() // ERROR "devirtualizing x.M"
}
{
i := 0 // ERROR "moved to heap: i"
v := &M2{&i} // ERROR "&M2{...} escapes to heap"
var x M = v
mescapes(x)
}
{
i := 0
v := &M2{&i} // ERROR "&M2{...} does not escape"
var x M = v
mdoesnotescape(x)
}
}
type T1 struct {
p *int
}
type T2 struct {
T1 T1
}
func dotTypeEscape() *T2 { // #11931
var x interface{}
x = &T1{p: new(int)} // ERROR "new\(int\) escapes to heap" "&T1{...} does not escape"
return &T2{ // ERROR "&T2{...} escapes to heap"
T1: *(x.(*T1)),
}
}
func dotTypeEscape2() { // #13805, #15796
{
i := 0
j := 0
var v int
var ok bool
var x interface{} = i // ERROR "i does not escape"
var y interface{} = j // ERROR "j does not escape"
*(&v) = x.(int)
*(&v), *(&ok) = y.(int)
}
{
i := 0
j := 0
var ok bool
var x interface{} = i // ERROR "i does not escape"
var y interface{} = j // ERROR "j does not escape"
sink = x.(int) // ERROR "x.\(int\) escapes to heap"
sink, *(&ok) = y.(int)
}
{
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
var ok bool
var x interface{} = &i
var y interface{} = &j
sink = x.(*int)
sink, *(&ok) = y.(*int)
}
}
func issue42279() {
type I interface{ M() }
type T struct{ I }
var i I = T{} // ERROR "T\{\} does not escape"
i.M() // ERROR "partially devirtualizing i.M to T"
}