深入go 源码学习

使用GODEV 跑标准库的test

1、设置GODEV 为自己的源码目录

$ GODEV= go 的绝对路径 eg: /data/app/go/src/gosrc/go

2、进入源码目录

$ cd $GODEV/src

3、设置引导安装到当前安装目录

use /

编译所有，包括单元测试

$ GOROOT_BOOTSTRAP=./ GO_GCFLAGS="-N -l" ./all.bash

编译

$ GOROOT_BOOTSTRAP=./ GO_GCFLAGS="-N -l" ./make.bash

不能 -+ compile: cannot disable optimizations while compiling runtime

use GOROOT

$ GOROOT_BOOTSTRAP=$(go env GOROOT) ./make.bash

$ GOOS=darwin GOARCH=amd64 ./bootstrap.bash

4、解决use of internal package cmd/internal/obj not allowed

GOROOT=/data/app/go/src/gosrc/go && export PATH=$GOROOT/bin:$PATH

4.1 default goroot

GOROOT=/usr/local/go && export PATH=$GOROOT/bin:$PATH

go test -v -run=Dynlink

5、go build go
$GODEV/bin/go run main.go build -debug-actiongraph="json"

展示整个编译链接的运行过程

go build -v -x -work -o main main.go

-v 会打印所编译过的包名字
-x 打印编译期间所执行的命令
-work 打印编译期间生成的临时文件路径，并且编译完成之后不会被删除

调试 cmd/go 进程启动

$GODEV/bin/go run /data/app/go/src/gosrc/go/src/cmd/go/main.go run /data/app/go/src/gosrc/demo/runtime/gc/gctodo/main.go

调试 cmd/compile 编译器

$GODEV/bin/go run /data/app/go/src/gosrc/go/src/cmd/compile/main.go -o main.o /data/app/go/src/gosrc/demo/type/type_definitions/method_set/main.go

$GODEV/bin/go run /data/app/go/src/gosrc/go/src/cmd/compile/main.go -o main.o /data/app/go/src/gosrc/demo/base_learn/slice/perform/main.go

调试 cmd/link 链接器

GOROOT=/data/app/go/src/gosrc/go && export PATH=$GOROOT/bin:$PATH
go run /data/app/go/src/gosrc/go/src/cmd/link/main.go -o main main.o

Building Go cmd/dist using /usr/local/go.
Building Go toolchain1 using /usr/local/go.
Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
Building Go toolchain2 using go_bootstrap and Go toolchain1.
Building Go toolchain3 using go_bootstrap and Go toolchain2.
Building packages and commands for darwin/amd64.
---
##### API check
Go version is "go", ignoring -next /data/app/go/src/go/api/next.txt
ALL TESTS PASSED
---
Installed Go for darwin/amd64 in /data/app/go/src/go
Installed commands in /data/app/go/src/go/bin
*** You need to add /data/app/go/src/go/bin to your PATH.

4、使用新编译的工具链运行所有测试

4.1 使用mod作为包管理工具
export GO111MODULE=on

4.2 默认使用当前目录名作为当前包名的mod，如果需要重命名则删除存在的mod，重新生成
$GODEV/bin/go mod init runtime

4.3、进入某个标准包下面运行单个测试

$GODEV/bin/go test -v -run=TestYieldLocked

=== RUN   TestYieldLockedProgress
--- PASS: TestYieldLockedProgress (0.01s)
=== RUN   TestYieldLocked
--- PASS: TestYieldLocked (0.01s)
PASS
ok      runtime    0.031s

$GODEV/bin/go test -run=NONE -v -bench=ChanProdCons0

goos: darwin
goarch: amd64
pkg: runtime
BenchmarkChanProdCons0-4         3000000               471 ns/op
PASS
ok      runtime 1.919s
`$GODEV/bin/go test -v -bench=. -run=Benchmark`
    ```
    goos: darwin
    goarch: amd64
    pkg: runtime
    BenchmarkMakeChan/Byte-4                        30000000                47.3 ns/op
    BenchmarkMakeChan/Int-4                         20000000                54.2 ns/op
    BenchmarkMakeChan/Ptr-4                         10000000               130 ns/op
    BenchmarkMakeChan/Struct/0-4                    30000000                41.3 ns/op
 ```

package main
import (
    "fmt"
)
func main() {
    fmt.Println("read go")
}