Cannot build and install go from source code from another tag

Question

I am trying to build and install go from source code using this documentation. This works fine when I do like the following:

 $ git clone https://go.googlesource.com/go goroot
 $ cd goroot
 $ git checkout master
 $ cd src
 $ ./all.bash`

Here I installed go from master branch. But when I checkout to another tag and try to execcute ./all.bash like following:

 $ git clone https://go.googlesource.com/go goroot
 $ cd goroot
 $ git checkout go1.12
 $ cd src
 $ ./all.bash`

this gives me the folowing error:

    go: cannot find main module, but found .git/config in /home/usr/goroot
    to create a module there, run:
    cd .. && go mod init`

I tried to do as the error message instructed i.e. go mod init , it gives me another error like the followig:

go: cannot determine module path for source directory /home/usr/goroot (outside GOPATH, module path must be specified)

Answer 1

The documentation is out of date.

---

Installing Go from source for Go 1.4 through Go 1.20 and devel go1.21.

# Go1.4 make.bash uses C - gcc and libc6-dev
$ git clone https://github.com/golang/go -b release-branch.go1.4 --depth 1 ~/go1.4
$ cd ~/go1.4/src && ./make.bash 2>/dev/null

$ git clone https://github.com/golang/go -b release-branch.go1.17 --depth 1 ~/go1.17.13
$ cd ~/go1.17.13/src && ./make.bash
Building Go toolchain1 using /home/rocka2q/go1.4.
Installed Go for linux/amd64 in /home/rocka2q/go1.17.13
Installed commands in /home/rocka2q/go1.17.13/bin

$ git clone https://github.com/golang/go ~/goroot
$ cd ~/goroot/src && git checkout master
Already on 'master'
Your branch is up to date with 'origin/master'.
$ cd ~/goroot/src && ./make.bash
Building Go toolchain1 using /home/rocka2q/go1.17.13.
Installed Go for linux/amd64 in /home/rocka2q/goroot
Installed commands in /home/rocka2q/goroot/bin
$ ~/goroot/bin/go version 
go version devel go1.21-0853f8caec Fri Apr 14 20:24:18 2023 +0000 linux/amd64

Checkout another tag.

$ cd ~/goroot/src && git checkout go1.12
HEAD is now at 05e77d4191 [release-branch.go1.12] go1.12
$ cd ~/goroot/src && ./make.bash
Building Go toolchain1 using /home/rocka2q/go1.4.
Installed Go for linux/amd64 in /home/rocka2q/goroot
Installed commands in /home/rocka2q/goroot/bin
$ ~/goroot/bin/go version 
go version go1.12 linux/amd64