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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.
// Tests escape analysis for range of arrays.
// Compiles but need not run. Inlining is disabled.
package main
type A struct {
b [3]uint64
}
type B struct {
b [3]*uint64
}
func f(a A) int {
for i, x := range &a.b {
if x != 0 {
return 64*i + int(x)
}
}
return 0
}
func g(a *A) int { // ERROR "a does not escape"
for i, x := range &a.b {
if x != 0 {
return 64*i + int(x)
}
}
return 0
}
func h(a *B) *uint64 { // ERROR "leaking param: a to result ~r0 level=1"
for i, x := range &a.b {
if i == 0 {
return x
}
}
return nil
}
func h2(a *B) *uint64 { // ERROR "leaking param: a to result ~r0 level=1"
p := &a.b
for i, x := range p {
if i == 0 {
return x
}
}
return nil
}
// Seems like below should be level=1, not 0.
func k(a B) *uint64 { // ERROR "leaking param: a to result ~r0 level=0"
for i, x := range &a.b {
if i == 0 {
return x
}
}
return nil
}
var sink *uint64
func main() {
var a1, a2 A
var b1, b2, b3, b4 B
var x1, x2, x3, x4 uint64 // ERROR "moved to heap: x1" "moved to heap: x3"
b1.b[0] = &x1
b2.b[0] = &x2
b3.b[0] = &x3
b4.b[0] = &x4
f(a1)
g(&a2)
sink = h(&b1)
h(&b2)
sink = h2(&b1)
h2(&b4)
x1 = 17
println("*sink=", *sink) // Verify that sink addresses x1
x3 = 42
sink = k(b3)
println("*sink=", *sink) // Verify that sink addresses x3
}
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