x/build/cmd/gorebuild: uses wrong path separator for running make.bat on Windows

[qiulaidongfeng]

What version of Go are you using (go version)?

$ go version
go version devel go1.22-3393155 Mon Aug 7 23:13:36 2023 +0000 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
set GO111MODULE=auto
set GOARCH=amd64
set GOBIN=
set GOCACHE=E:\TEMP\go-build
set GOENV=C:\Users\Administrator\AppData\Roaming\go\env
set GOEXE=.exe
set GOEXPERIMENT=
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GOMODCACHE=E:\gofile\pkg\mod
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=E:\gofile
set GOPRIVATE=
set GOPROXY=https://goproxy.cn,https://proxy.golang.org,direct
set GOROOT=C:\Users\Administrator\.go\current
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLCHAIN=local
set GOTOOLDIR=C:\Users\Administrator\.go\current\pkg\tool\windows_amd64
set GOVCS=
set GOVERSION=devel go1.22-3393155 Mon Aug 7 23:13:36 2023 +0000
set GCCGO=gccgo
set GOAMD64=v2
set AR=ar
set CC=clang
set CXX=clang++
set CGO_ENABLED=0
set GOMOD=E:\TEMP\gorebuild-1498172390\repro-go1.21.0-windows-amd64\src\go.mod
set GOWORK=
set CGO_CFLAGS=-O2 -g
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-O2 -g
set CGO_FFLAGS=-O2 -g
set CGO_LDFLAGS=-O2 -g
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -fno-caret-diagnostics -Qunused-arguments -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=E:\TEMP\go-build4003734977=/tmp/go-build -gno-record-gcc-switches
GOROOT/bin/go version: go version devel go1.22-3393155 Mon Aug 7 23:13:36 2023 +0000 windows/amd64
GOROOT/bin/go tool compile -V: compile version devel go1.22-3393155 Mon Aug 7 23:13:36 2023 +0000
lldb --version: lldb version 16.0.5
gdb --version: GNU gdb (GDB for MinGW-W64 x86_64, built by Brecht Sanders) 13.2

What did you do?

On the Winwods computer.

go install golang.org/x/build/cmd/gorebuild@latest

gorebuild windows-amd64

What did you expect to see?

Program runs normally.

What did you see instead?

12:58:06.689 downloaded https://go.dev/dl/?mode=json&include=all
12:58:07.058 [bootstrap go1.17] using go1.17.13 binary distribution for go1.17
12:59:16.161 [bootstrap go1.17] downloaded https://go.dev/dl/go1.17.13.windows-amd64.zip
12:59:44.885 [go1.21.0] downloaded https://go.googlesource.com/go/+archive/refs/tags/go1.21.0.tar.gz
12:59:44.885 [go1.21.0.windows-amd64.zip] start go1.21.0.windows-amd64.zip
12:59:58.284 [go1.21.0.windows-amd64.zip] running ./make.bat env=[GOOS=windows GOARCH=amd64] args=[-distpack]
GOROOT=E:\TEMP\gorebuild-4074831885\repro-go1.21.0-windows-amd64
GOROOT_BOOTSTRAP=E:\TEMP\gorebuild-4074831885\bootstrap-go1.17\go
12:59:58.357 [go1.21.0.windows-amd64.zip] ./make.bat: exit status 1
'.' is not recognized as an internal or external command,
operable program or batch file.
13:00:07.187 [go1.21.0.windows-amd64.zip] FAIL: ./make.bat in E:\TEMP\gorebuild-4074831885\repro-go1.21.0-windows-amd64 failed
13:00:07.189 [go1.21.0.src.tar.gz] FAIL: file not checked
13:00:07.189 [go1.21.0] FAIL: go1.21.0.src.tar.gz did not verify
13:00:07.190 [go1.21.0.windows-amd64.msi] FAIL: file not checked
13:00:07.190 [go1.21.0] FAIL: go1.21.0.windows-amd64.msi did not verify
13:00:07.190 [go1.21.0] FAIL: go1.21.0.windows-amd64.zip did not verify
13:00:07.190 [v0.0.1-go1.21.0.windows-amd64.info] FAIL: file not checked
13:00:07.190 [go1.21.0] FAIL: v0.0.1-go1.21.0.windows-amd64.info did not verify
13:00:07.191 [v0.0.1-go1.21.0.windows-amd64.mod] FAIL: file not checked
13:00:07.191 [go1.21.0] FAIL: v0.0.1-go1.21.0.windows-amd64.mod did not verify
13:00:07.191 [v0.0.1-go1.21.0.windows-amd64.zip] FAIL: file not checked
13:00:07.192 [go1.21.0] FAIL: v0.0.1-go1.21.0.windows-amd64.zip did not verify
13:00:07.193 FAIL: go1.21.0 did not verify

[qiulaidongfeng]

seem to be https://github.com/golang/go/blob/master/src/os/exec/lp_windows.go#L101 Causing this issue.
If it is changed to return lp+ext, nil, the correct absolute path will be returned, but go test os/exec will fail.
output：

--- FAIL: TestCommand (3.59s)
--- FAIL: TestCommand/15 (0.41s)
lp_windows_test.go:396: test={PATH:p2 files:[p\a.exe p2\a.exe] dir:p arg0:.\a want:p\a.exe fails:false}: exec: exit status 1 Child: fork/exec p\a.exe.exe: The system cannot find the path specified.
FAIL
exit status 1

[qmuntal]

Does this issue reproduces with go1.21? Else, can it be a regression from CL 512155?

[qiulaidongfeng]

Both go1.21.0 and tip will reproduce on my computer.

[bcmills]

@gopherbot, please backport to Go 1.21. This is a regression from previous Go releases.

[gopherbot]

Backport issue(s) opened: #61957 (for 1.21).

Remember to create the cherry-pick CL(s) as soon as the patch is submitted to master, according to https://go.dev/wiki/MinorReleases.

[qmuntal]

@bcmills I don't think this is a regression. I can reproduce the same issue with all previous versions till at least go 1.12 using this self-contained reproducer:

package main

import (
	"fmt"
	"io/ioutil" // for compatibility with old Go versions
	"os"
	"os/exec"
)

func main() {
	const make = "./make.bat"
	err := ioutil.WriteFile(make, []byte("echo \"Hello\""), 0666)
	if err != nil {
		fmt.Printf("error writing make.bat: %s", err)
		os.Exit(1)
	}
	out, err := exec.Command(make).CombinedOutput()
	if err != nil {
		fmt.Printf("%s: %s\n%s", make, err, out)
		os.Exit(1)
	}
	fmt.Printf("%s completed:\n%s", make, out)
}

C:\Users\qmuntaldiaz\code\gotest>go1.12.1 run main.go 
./make.bat: exit status 1
'.' is not recognized as an internal or external command,
operable program or batch file.
exit status 1

The issue is fixed if replacing ./make.bat to .\\make.bat.

Same behavior if using just cmd:

C:\Users\qmuntaldiaz\code\gotest>./make.bat
'.' is not recognized as an internal or external command,
operable program or batch file.

[gopherbot]

Change https://go.dev/cl/518735 mentions this issue: cmd/gorebuild: fix running gorebuild on Windows