[I] function StringToBytesWithNoCopy(s string) in pkg/util/util.go have some problems in GC scenarios [servicecomb-service-center]

["colin-si (via GitHub)" <gi...@apache.org>]

colin-si opened a new issue, #1432:
URL: https://github.com/apache/servicecomb-service-center/issues/1432

   **Describe the bug**
   The return result of the StringToBytesWithNoCopy function will be recycled by GC when a large number of objects are created.
   
   **To Reproduce**
   The following demo can reproduce this problem
   ```
   var ResultKey []byte
   
   func main() {
   	key:=[]byte("123456789")
   	ResultKey = StringToBytesWithNoCopy(string(key))
   	// Result is normal before gc
   	log.Printf("before runtime.gc and makeEscape: %v\n", string(ResultKey))
   	runtime.GC()
   	for i:=1;i<5000;i++{
   		makeEscape(time.Now().String())
   	}
   	// Result has been recycled after gc
   	log.Printf("after runtime.gc and makeEscape: %v\n",string(ResultKey))
   }
   
   func makeEscape(input string)string  {
   	return  input
   }
   
   // method copy from servicecomb-service-center/pkg/util/util.go
   func StringToBytesWithNoCopy(s string) []byte {
   	x := (*[2]uintptr)(unsafe.Pointer(&s))
   	h := [3]uintptr{x[0], x[1], x[1]}
   	return *(*[]byte)(unsafe.Pointer(&h))
   }
   
   // use this method can solve the problem
   func StringToBytesWithNoCopyNew(str string) []byte {
   	return *(*[]byte)(unsafe.Pointer(
   		&struct {
   			string
   			Cap int
   		}{str, len(str)},
   	))
   }
   ```
   
   
   
   **Expected behavior**
   When we executed the above demo, we found that the returned results were recycled after GC. This was unexpected. The memory where ResultKey is located is recycled and reallocated for use elsewhere.
   ```
   2023/12/13 10:57:20 before runtime.gc and makeEscape: 123456789
   2023/12/13 10:57:20 after runtime.gc and makeEscape:  m=+0.017
   ```
   
   **Platform And Runtime (please complete the following information):**
   
   Platform
    - OS: [e.g. iOS]
    - Browser [e.g. chrome, safari]
    - Version [e.g. 22]
   
   Runtime
    - Version [e.g. Go 1.11]
   
   **Additional context**
   Add any other context about the problem here.
   


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