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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 through ... parameters.
package foo
func FooN(vals ...*int) (s int) { // ERROR "vals does not escape"
for _, v := range vals {
s += *v
}
return s
}
// Append forces heap allocation and copies entries in vals to heap, therefore they escape to heap.
func FooNx(x *int, vals ...*int) (s int) { // ERROR "leaking param: x" "leaking param content: vals"
vals = append(vals, x)
return FooN(vals...)
}
var sink []*int
func FooNy(x *int, vals ...*int) (s int) { // ERROR "leaking param: x" "leaking param: vals"
vals = append(vals, x)
sink = vals
return FooN(vals...)
}
func FooNz(vals ...*int) (s int) { // ERROR "leaking param: vals"
sink = vals
return FooN(vals...)
}
func TFooN() {
for i := 0; i < 1000; i++ {
var i, j int
FooN(&i, &j) // ERROR "... argument does not escape"
}
}
func TFooNx() {
for i := 0; i < 1000; i++ {
var i, j, k int // ERROR "moved to heap: i" "moved to heap: j" "moved to heap: k"
FooNx(&k, &i, &j) // ERROR "... argument does not escape"
}
}
func TFooNy() {
for i := 0; i < 1000; i++ {
var i, j, k int // ERROR "moved to heap: i" "moved to heap: j" "moved to heap: k"
FooNy(&k, &i, &j) // ERROR "... argument escapes to heap"
}
}
func TFooNz() {
for i := 0; i < 1000; i++ {
var i, j int // ERROR "moved to heap: i" "moved to heap: j"
FooNz(&i, &j) // ERROR "... argument escapes to heap"
}
}
var isink *int32
func FooI(args ...interface{}) { // ERROR "leaking param content: args"
for i := 0; i < len(args); i++ {
switch x := args[i].(type) {
case nil:
println("is nil")
case int32:
println("is int32")
case *int32:
println("is *int32")
isink = x
case string:
println("is string")
}
}
}
func TFooI() {
a := int32(1) // ERROR "moved to heap: a"
b := "cat"
c := &a
FooI(a, b, c) // ERROR "a escapes to heap" "b escapes to heap" "... argument does not escape"
}
func FooJ(args ...interface{}) *int32 { // ERROR "leaking param: args to result ~r1 level=1"
for i := 0; i < len(args); i++ {
switch x := args[i].(type) {
case nil:
println("is nil")
case int32:
println("is int32")
case *int32:
println("is *int32")
return x
case string:
println("is string")
}
}
return nil
}
func TFooJ1() {
a := int32(1)
b := "cat"
c := &a
FooJ(a, b, c) // ERROR "a does not escape" "b does not escape" "... argument does not escape"
}
func TFooJ2() {
a := int32(1) // ERROR "moved to heap: a"
b := "cat"
c := &a
isink = FooJ(a, b, c) // ERROR "a escapes to heap" "b escapes to heap" "... argument does not escape"
}
type fakeSlice struct {
l int
a *[4]interface{}
}
func FooK(args fakeSlice) *int32 { // ERROR "leaking param: args to result ~r1 level=1"
for i := 0; i < args.l; i++ {
switch x := (*args.a)[i].(type) {
case nil:
println("is nil")
case int32:
println("is int32")
case *int32:
println("is *int32")
return x
case string:
println("is string")
}
}
return nil
}
func TFooK2() {
a := int32(1) // ERROR "moved to heap: a"
b := "cat"
c := &a
fs := fakeSlice{3, &[4]interface{}{a, b, c, nil}} // ERROR "a escapes to heap" "b escapes to heap" "&\[4\]interface {}{...} does not escape"
isink = FooK(fs)
}
func FooL(args []interface{}) *int32 { // ERROR "leaking param: args to result ~r1 level=1"
for i := 0; i < len(args); i++ {
switch x := args[i].(type) {
case nil:
println("is nil")
case int32:
println("is int32")
case *int32:
println("is *int32")
return x
case string:
println("is string")
}
}
return nil
}
func TFooL2() {
a := int32(1) // ERROR "moved to heap: a"
b := "cat"
c := &a
s := []interface{}{a, b, c} // ERROR "a escapes to heap" "b escapes to heap" "\[\]interface {}{...} does not escape"
isink = FooL(s)
}
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