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golang闭包中变量获取

news 来源：原创 2024/9/20 15:30:46

闭包的本质是一个语法糖，其本质是获取外部变量在其内部使用。文中case2和case3并未涉及闭包，只是作为对比案例。case4这个案例有点不能理解，汇编看着太吃力了。case4和case5留待后续再研究。

案例1：

package main// 探究go语言中闭包如何捕获变量
func main() {i := 10closureByValue := func() int {return i}closureByValue()
}

我们直接利用go的compile工具看一下汇编的情况。我用的是windows电脑，在命令行终端敲上这个命令：

go tool compile -l -S main.go | findstr "main.go"

 0x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:4)        TEXT    main.main(SB), ABIInternal, $24-00x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:4)        CMPQ    SP, 16(R14)0x0004 00004 (E:/Go/src/tool/closure/closure1/main.go:4)        PCDATA  $0, $-20x0004 00004 (E:/Go/src/tool/closure/closure1/main.go:4)        JLS     550x0006 00006 (E:/Go/src/tool/closure/closure1/main.go:4)        PCDATA  $0, $-10x0006 00006 (E:/Go/src/tool/closure/closure1/main.go:4)        PUSHQ   BP0x0007 00007 (E:/Go/src/tool/closure/closure1/main.go:4)        MOVQ    SP, BP0x000a 00010 (E:/Go/src/tool/closure/closure1/main.go:4)        SUBQ    $16, SP0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:4)        FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:4)        FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVUPS  X15, main..autotmp_3(SP)0x0013 00019 (E:/Go/src/tool/closure/closure1/main.go:6)        LEAQ    main.main.func1(SB), AX0x001a 00026 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVQ    AX, main..autotmp_3(SP)0x001e 00030 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVQ    $10, main..autotmp_3+8(SP)0x0027 00039 (E:/Go/src/tool/closure/closure1/main.go:9)        MOVQ    main..autotmp_3(SP), AX0x002b 00043 (E:/Go/src/tool/closure/closure1/main.go:9)        LEAQ    main..autotmp_3(SP), DX0x002f 00047 (E:/Go/src/tool/closure/closure1/main.go:9)        PCDATA  $1, $00x002f 00047 (E:/Go/src/tool/closure/closure1/main.go:9)        CALL    AX0x0031 00049 (E:/Go/src/tool/closure/closure1/main.go:10)       ADDQ    $16, SP0x0035 00053 (E:/Go/src/tool/closure/closure1/main.go:10)       POPQ    BP0x0036 00054 (E:/Go/src/tool/closure/closure1/main.go:10)       RET0x0037 00055 (E:/Go/src/tool/closure/closure1/main.go:10)       NOP0x0037 00055 (E:/Go/src/tool/closure/closure1/main.go:4)        PCDATA  $1, $-10x0037 00055 (E:/Go/src/tool/closure/closure1/main.go:4)        PCDATA  $0, $-20x0037 00055 (E:/Go/src/tool/closure/closure1/main.go:4)        CALL    runtime.morestack_noctxt(SB)0x003c 00060 (E:/Go/src/tool/closure/closure1/main.go:4)        PCDATA  $0, $-10x003c 00060 (E:/Go/src/tool/closure/closure1/main.go:4)        JMP     00x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:6)        TEXT    main.main.func1(SB), NOSPLIT|NEEDCTXT|NOFRAME|ABIInternal, $0-00x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:6)        FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:6)        FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVQ    8(DX), AX0x0004 00004 (E:/Go/src/tool/closure/closure1/main.go:7)        RET

我们重点关注闭包函数及变量。

函数数据与局部变量的初始化

0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:4)        FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)  
0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:4)        FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)  
0x000e 00014 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVUPS  X15, main..autotmp_3(SP)  
0x0013 00019 (E:/Go/src/tool/closure/closure1/main.go:6)        LEAQ    main.main.func1(SB), AX  
0x001a 00026 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVQ    AX, main..autotmp_3(SP)  
0x001e 00030 (E:/Go/src/tool/closure/closure1/main.go:6)        MOVQ    $10, main..autotmp_3+8(SP)

FUNCDATA 包含一些垃圾收集器使用的元数据。
MOVUPS 将X15寄存器的内容复制到栈上的局部变量main..autotmp_3。
LEAQ 加载main.main.func1的地址到AX寄存器。
MOVQ AX, main..autotmp_3(SP) 将AX的值（即main.main.func1的地址）存储到栈上。
MOVQ $10, main..autotmp_3+8(SP) 将常数10存储到栈上的另一个位置。

调用闭包函数

0x0027 00039 (E:/Go/src/tool/closure/closure1/main.go:9)        MOVQ    main..autotmp_3(SP), AX  
0x002b 00043 (E:/Go/src/tool/closure/closure1/main.go:9)        LEAQ    main..autotmp_3(SP), DX  
0x002f 00047 (E:/Go/src/tool/closure/closure1/main.go:9)        PCDATA  $1, $0  
0x002f 00047 (E:/Go/src/tool/closure/closure1/main.go:9)        CALL    AX

MOVQ main..autotmp_3(SP), AX 将闭包函数的地址从栈加载到AX寄存器。
LEAQ main..autotmp_3(SP), DX 将闭包数据的地址加载到DX寄存器。
CALL AX 调用AX寄存器中地址指向的函数，即main.main.func1。

所以，闭包实际上，是把函数外的变量复制到了函数内，供函数内部使用。

案例2：

package mainimport ("fmt""time"
)func passByValue(value int) {fmt.Println(value)
}func main() {for i := 0; i < 10; i++ {go passByValue(i)}time.Sleep(time.Second * 100)
}

这种情况下输出的结果是符合我们的预期的。因为，虽然起了协程，在这个循环中，每次迭代，i 的值会被传递到 passByValue 中。

案例3：

package mainimport ("fmt""time"
)
func passByRef(value *int) int {fmt.Println(*value)return *value
}func main() {for i := 0; i < 10; i++ {go passByRef(&i)}time.Sleep(time.Second * 100)
}

大家猜一下，这种情况下，这种情况下输出的是什么？

这种情况似乎是可以理解的，所有的 goroutine 都在并发执行，并且它们都共享同一个 i 变量的地址。由于 for 循环在 goroutine 启动后继续执行，并且 i 的值会在每次迭代中增加，最终所有 goroutine 都会打印出 i 的最终值。

因此，输出的结果将是 10，因为当所有 goroutine 开始执行时，i 的值已经增加到 10。具体来说，可能会打印出多次 10，具体数量取决于 goroutine 的调度。我的版本是go1.21.5

这里我的函数名是passByRef,似乎有点让人误解，让人误以为是传引用的传参方式，go里面其实没有这种用法，本质上只是拷贝指针的地址传递到函数内。关于这个问题的探究，我在另一篇文章中《golang函数传参——值传递理解》有写过，有兴趣的可以移步过去看看。

但是在go的在线工具中执行，却是这种结果，有点不能理解啊。这个是go1.22的版本，执行的结果。难道新版本有什么改动么？这个遗留问题，后续有时间再研究研究。

case4:

package mainimport ("fmt""time"
)func passByVal(value int) int {fmt.Println(value)return value
}func main() {for i := 0; i < 10; i++ {go func() {passByVal(i)}()}time.Sleep(time.Second * 100)
}

先看起其执行结果。

再来思考一下，为什么会是这样的执行结果。

首先，看一下汇编的结果。

0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        TEXT    main.passByVal(SB), NOSPLIT|NOFRAME|ABIInternal, $0-80x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        FUNCDATA        $5, main.passByVal.arginfo1(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        FUNCDATA        $6, main.passByVal.argliveinfo(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:8)        PCDATA  $3, $10x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:10)       RET0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:17)       TEXT    main.main(SB), ABIInternal, $32-00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:17)       CMPQ    SP, 16(R14)0x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-20x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:17)       JLS     1170x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-10x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:17)       PUSHQ   BP0x0007 00007 (E:/Go/src/tool/closure/closure3/main.go:17)       MOVQ    SP, BP0x000a 00010 (E:/Go/src/tool/closure/closure3/main.go:17)       SUBQ    $24, SP0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:17)       FUNCDATA        $0, gclocals?J5F+7Qw7O7ve2QcWC7DpeQ==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:17)       FUNCDATA        $1, gclocals?CnDyI2HjYXFz19SsOj98tw==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:21)       LEAQ    type:int(SB), AX0x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:21)       PCDATA  $1, $00x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:21)       CALL    runtime.newobject(SB)0x001a 00026 (E:/Go/src/tool/closure/closure3/main.go:21)       MOVQ    AX, main.&i+16(SP)0x001f 00031 (E:/Go/src/tool/closure/closure3/main.go:21)       NOP0x0020 00032 (E:/Go/src/tool/closure/closure3/main.go:21)       JMP     510x0022 00034 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-20x0022 00034 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    DX, 8(AX)0x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-10x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $1, $10x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:22)       CALL    runtime.newproc(SB)0x002b 00043 (E:/Go/src/tool/closure/closure3/main.go:21)       MOVQ    main.&i+16(SP), AX0x0030 00048 (E:/Go/src/tool/closure/closure3/main.go:21)       INCQ    (AX)0x0033 00051 (E:/Go/src/tool/closure/closure3/main.go:21)       CMPQ    (AX), $100x0037 00055 (E:/Go/src/tool/closure/closure3/main.go:21)       JGE     1110x0039 00057 (E:/Go/src/tool/closure/closure3/main.go:22)       LEAQ    type:noalg.struct { F uintptr; X0 *int }(SB), AX0x0040 00064 (E:/Go/src/tool/closure/closure3/main.go:22)       CALL    runtime.newobject(SB)0x0045 00069 (E:/Go/src/tool/closure/closure3/main.go:22)       LEAQ    main.main.func1(SB), CX0x004c 00076 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    CX, (AX)0x004f 00079 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-20x004f 00079 (E:/Go/src/tool/closure/closure3/main.go:22)       CMPL    runtime.writeBarrier(SB), $00x0056 00086 (E:/Go/src/tool/closure/closure3/main.go:22)       JNE     960x0058 00088 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    main.&i+16(SP), DX0x005d 00093 (E:/Go/src/tool/closure/closure3/main.go:22)       JMP     340x005f 00095 (E:/Go/src/tool/closure/closure3/main.go:22)       NOP0x0060 00096 (E:/Go/src/tool/closure/closure3/main.go:22)       CALL    runtime.gcWriteBarrier1(SB)0x0065 00101 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    main.&i+16(SP), DX0x006a 00106 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    DX, (R11)0x006d 00109 (E:/Go/src/tool/closure/closure3/main.go:22)       JMP     340x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       PCDATA  $0, $-10x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       PCDATA  $1, $-10x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       ADDQ    $24, SP0x0073 00115 (E:/Go/src/tool/closure/closure3/main.go:32)       POPQ    BP0x0074 00116 (E:/Go/src/tool/closure/closure3/main.go:32)       RET0x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:32)       NOP0x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $1, $-10x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-20x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       CALL    runtime.morestack_noctxt(SB)0x007a 00122 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-10x007a 00122 (E:/Go/src/tool/closure/closure3/main.go:17)       JMP     00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:22)       TEXT    main.main.func1(SB), NEEDCTXT|ABIInternal, $16-00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:22)       CMPQ    SP, 16(R14)0x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-20x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:22)       JLS     330x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-10x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:22)       PUSHQ   BP0x0007 00007 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    SP, BP0x000a 00010 (E:/Go/src/tool/closure/closure3/main.go:22)       SUBQ    $8, SP0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:22)       FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:22)       FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:22)       MOVQ    8(DX), CX0x0012 00018 (E:/Go/src/tool/closure/closure3/main.go:23)       MOVQ    (CX), AX0x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:23)       PCDATA  $1, $00x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:23)       CALL    main.passByVal(SB)0x001a 00026 (E:/Go/src/tool/closure/closure3/main.go:24)       ADDQ    $8, SP0x001e 00030 (E:/Go/src/tool/closure/closure3/main.go:24)       POPQ    BP0x001f 00031 (E:/Go/src/tool/closure/closure3/main.go:24)       NOP0x0020 00032 (E:/Go/src/tool/closure/closure3/main.go:24)       RET0x0021 00033 (E:/Go/src/tool/closure/closure3/main.go:24)       NOP0x0021 00033 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $1, $-10x0021 00033 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-20x0021 00033 (E:/Go/src/tool/closure/closure3/main.go:22)       CALL    runtime.morestack(SB)0x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:22)       PCDATA  $0, $-10x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:22)       JMP     0

case5:

package mainimport ("fmt""time"
)func passByRef(value *int) int {fmt.Println(*value)return *value
}func main() {for i := 0; i < 10; i++ {go func() {passByRef(&i)}()}time.Sleep(time.Second * 100)
}

同样的先看一下其执行结果：

再结合其汇编代码看一下为什么会是这样的结果。

 0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       TEXT    main.passByRef(SB), NOSPLIT|NOFRAME|ABIInternal, $0-80x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       FUNCDATA        $0, gclocals?wgcWObbY2HYnK2SU/U22lA==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       FUNCDATA        $1, gclocals?J5F+7Qw7O7ve2QcWC7DpeQ==(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       FUNCDATA        $5, main.passByRef.arginfo1(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       FUNCDATA        $6, main.passByRef.argliveinfo(SB)0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:12)       PCDATA  $3, $10x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:14)       MOVQ    (AX), AX0x0003 00003 (E:/Go/src/tool/closure/closure3/main.go:14)       RET0x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:17)       TEXT    main.main(SB), ABIInternal, $32-00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:17)       CMPQ    SP, 16(R14)0x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-20x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:17)       JLS     1170x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-10x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:17)       PUSHQ   BP0x0007 00007 (E:/Go/src/tool/closure/closure3/main.go:17)       MOVQ    SP, BP0x000a 00010 (E:/Go/src/tool/closure/closure3/main.go:17)       SUBQ    $24, SP0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:17)       FUNCDATA        $0, gclocals?J5F+7Qw7O7ve2QcWC7DpeQ==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:17)       FUNCDATA        $1, gclocals?CnDyI2HjYXFz19SsOj98tw==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:26)       LEAQ    type:int(SB), AX0x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:26)       PCDATA  $1, $00x0015 00021 (E:/Go/src/tool/closure/closure3/main.go:26)       CALL    runtime.newobject(SB)0x001a 00026 (E:/Go/src/tool/closure/closure3/main.go:26)       MOVQ    AX, main.&i+16(SP)0x001f 00031 (E:/Go/src/tool/closure/closure3/main.go:26)       NOP0x0020 00032 (E:/Go/src/tool/closure/closure3/main.go:26)       JMP     510x0022 00034 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-20x0022 00034 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    DX, 8(AX)0x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-10x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $1, $10x0026 00038 (E:/Go/src/tool/closure/closure3/main.go:27)       CALL    runtime.newproc(SB)0x002b 00043 (E:/Go/src/tool/closure/closure3/main.go:26)       MOVQ    main.&i+16(SP), AX0x0030 00048 (E:/Go/src/tool/closure/closure3/main.go:26)       INCQ    (AX)0x0033 00051 (E:/Go/src/tool/closure/closure3/main.go:26)       CMPQ    (AX), $100x0037 00055 (E:/Go/src/tool/closure/closure3/main.go:26)       JGE     1110x0039 00057 (E:/Go/src/tool/closure/closure3/main.go:27)       LEAQ    type:noalg.struct { F uintptr; X0 *int }(SB), AX0x0040 00064 (E:/Go/src/tool/closure/closure3/main.go:27)       CALL    runtime.newobject(SB)0x0045 00069 (E:/Go/src/tool/closure/closure3/main.go:27)       LEAQ    main.main.func1(SB), CX0x004c 00076 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    CX, (AX)0x004f 00079 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-20x004f 00079 (E:/Go/src/tool/closure/closure3/main.go:27)       CMPL    runtime.writeBarrier(SB), $00x0056 00086 (E:/Go/src/tool/closure/closure3/main.go:27)       JNE     960x0058 00088 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    main.&i+16(SP), DX0x005d 00093 (E:/Go/src/tool/closure/closure3/main.go:27)       JMP     340x005f 00095 (E:/Go/src/tool/closure/closure3/main.go:27)       NOP0x0060 00096 (E:/Go/src/tool/closure/closure3/main.go:27)       CALL    runtime.gcWriteBarrier1(SB)0x0065 00101 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    main.&i+16(SP), DX0x006a 00106 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    DX, (R11)0x006d 00109 (E:/Go/src/tool/closure/closure3/main.go:27)       JMP     340x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       PCDATA  $0, $-10x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       PCDATA  $1, $-10x006f 00111 (E:/Go/src/tool/closure/closure3/main.go:32)       ADDQ    $24, SP0x0073 00115 (E:/Go/src/tool/closure/closure3/main.go:32)       POPQ    BP0x0074 00116 (E:/Go/src/tool/closure/closure3/main.go:32)       RET0x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:32)       NOP0x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $1, $-10x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-20x0075 00117 (E:/Go/src/tool/closure/closure3/main.go:17)       CALL    runtime.morestack_noctxt(SB)0x007a 00122 (E:/Go/src/tool/closure/closure3/main.go:17)       PCDATA  $0, $-10x007a 00122 (E:/Go/src/tool/closure/closure3/main.go:17)       JMP     00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:27)       TEXT    main.main.func1(SB), NEEDCTXT|ABIInternal, $16-00x0000 00000 (E:/Go/src/tool/closure/closure3/main.go:27)       CMPQ    SP, 16(R14)0x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-20x0004 00004 (E:/Go/src/tool/closure/closure3/main.go:27)       JLS     290x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-10x0006 00006 (E:/Go/src/tool/closure/closure3/main.go:27)       PUSHQ   BP0x0007 00007 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    SP, BP0x000a 00010 (E:/Go/src/tool/closure/closure3/main.go:27)       SUBQ    $8, SP0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:27)       FUNCDATA        $0, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:27)       FUNCDATA        $1, gclocals?g2BeySu+wFnoycgXfElmcg==(SB)0x000e 00014 (E:/Go/src/tool/closure/closure3/main.go:27)       MOVQ    8(DX), AX0x0012 00018 (E:/Go/src/tool/closure/closure3/main.go:28)       PCDATA  $1, $00x0012 00018 (E:/Go/src/tool/closure/closure3/main.go:28)       CALL    main.passByRef(SB)0x0017 00023 (E:/Go/src/tool/closure/closure3/main.go:29)       ADDQ    $8, SP0x001b 00027 (E:/Go/src/tool/closure/closure3/main.go:29)       POPQ    BP0x001c 00028 (E:/Go/src/tool/closure/closure3/main.go:29)       RET0x001d 00029 (E:/Go/src/tool/closure/closure3/main.go:29)       NOP0x001d 00029 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $1, $-10x001d 00029 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-20x001d 00029 (E:/Go/src/tool/closure/closure3/main.go:27)       NOP0x0020 00032 (E:/Go/src/tool/closure/closure3/main.go:27)       CALL    runtime.morestack(SB)0x0025 00037 (E:/Go/src/tool/closure/closure3/main.go:27)       PCDATA  $0, $-10x0025 00037 (E:/Go/src/tool/closure/closure3/main.go:27)       JMP     0