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// run
// Copyright 2018 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.
// Make sure return values are always scanned, when
// calling methods (+functions, TODO) with reflect.
package main
import (
"reflect"
"runtime/debug"
"sync"
)
func main() {
debug.SetGCPercent(1) // run GC frequently
var wg sync.WaitGroup
for i := 0; i < 20; i++ {
wg.Add(1)
go func() {
defer wg.Done()
for i := 0; i < 2000; i++ {
_test()
}
}()
}
wg.Wait()
}
type Stt struct {
Data interface{}
}
type My struct {
b byte
}
func (this *My) Run(rawData []byte) (Stt, error) {
var data string = "hello"
stt := Stt{
Data: data,
}
return stt, nil
}
func _test() (interface{}, error) {
f := reflect.ValueOf(&My{}).MethodByName("Run")
if method, ok := f.Interface().(func([]byte) (Stt, error)); ok {
s, e := method(nil)
// The bug in issue27695 happens here, during the return
// from the above call (at the end of reflect.callMethod
// when preparing to return). The result value that
// is assigned to s was not being scanned if GC happens
// to occur there.
i := interface{}(s)
return i, e
}
return nil, nil
}
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