[go-nuts] A value copy will occur when executing for range xxx？

[mountainfpf]

package main

func main() {
b := []int{1}

bb := make([]*int, 0, 1)
for k, v := range b {
_ = &v  //8 line
_ = &b[k] //9 line
// bb = append(bb, &v)
bb = append(bb, &b[k])
}

// for _, v := range bb {
// fmt.Println(*v)
// }
}

1、When i use `go too compile -N -l -S main.go |grep "main.go:8" ` print asm 
on line 8, it print nothing.
2、When i use `go too compile -N -l -S main.go |grep "main.go:9" ` print asm 
on line 8, it print some asm code:

        0x0136 00310 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     MOVQ    
"".b+168(SP), CX
        0x013e 00318 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     CMPQ    
"".k+72(SP), CX
        0x0143 00323 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     JCS    
 330
        0x0145 00325 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     JMP    
 583
        0x0247 00583 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     CALL    
runtime.panicindex(SB)
        0x024c 00588 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     UNDEF
        0x024e 00590 
(/data/app/go/src/gosrc/demo/base_learn/slice/range/main.go:9)     NOP

so it because a copy of the array/slice variable ?

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