Doubt about behaviour of unsafe.Pointer when converting string to int32 #42046
Description
What version of Go are you using (go version)?
PS C:\Users\cliente\Desktop\gostudies> go version go version go1.15.3 windows/amd64
Does this issue reproduce with the latest release?
Yes.
What operating system and processor architecture are you using (go env)?
go env Output
$ go env
What did you do?
I'm studying about the unsafe.Pointer when working with pointers.
I looked that the unsafe.Pointer should return a float, or an int into another format, for example:
If I have an int64 variable pointer, I should transform into int32 by the (*int32)(unsafe.Pointer(t.value)) usage.
package main
import (
"fmt"
"unsafe"
)
type test struct {
value *int64
}
func main() {
var v int64
v = 123
t := test{&v}
var ptest = (*int32)(unsafe.Pointer(t.value))
fmt.Println(ptest)
fmt.Println(*ptest + 10)
}
This is good behavior.
So, I tried to change the int32 of the unsafe.Pointer to string like this function:
package main
import (
"fmt"
"unsafe"
)
type test struct {
value *string
}
func main() {
var v string
v = "123"
t := test{&v}
var ptest = (*int32)(unsafe.Pointer(t.value))
fmt.Println(ptest)
fmt.Println(*ptest + 10)
}
When I did it, I am getting the following response from execution:
PS C:\Users\cliente\Desktop\gostudies> go run main.go
0xc00004a1f0
17736171
What did you expect to see?
I expected to convert my "123" to 123 integer to sum with my 10 number.
What did you see instead?
This number 17736171 is a "random" number.
What does the 17736171 meaning in this case?