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

$ go version
go version devel go1.21-b9baf4452f Thu Jun 8 01:52:35 2023 +0000 windows/amd64

Does this issue reproduce with the latest release?

Only with tip.

What operating system and processor architecture are you using (go env)?

$ go env
set GO111MODULE=

set GOARCH=amd64

set GOBIN=

set GOCACHE=C:\Users*\AppData\Local\go-build

set GOENV=C:\Users*\AppData\Roaming\go\env

set GOEXE=.exe

set GOEXPERIMENT=

set GOFLAGS=

set GOHOSTARCH=amd64

set GOHOSTOS=windows

set GOINSECURE=

set GOMODCACHE=C:\Users*\go\pkg\mod

set GONOPROXY=

set GONOSUMDB=

set GOOS=windows

set GOPATH=C:\Users*\go

set GOPRIVATE=

set GOPROXY=https://proxy.golang.org,direct

set GOROOT=C:\Users*\code\golang-go

set GOSUMDB=sum.golang.org

set GOTMPDIR=

set GOTOOLCHAIN=local

set GOTOOLDIR=C:\Users*\code\golang-go\pkg\tool\windows_amd64

set GOVCS=

set GOVERSION=devel go1.21-b9baf4452f Thu Jun 8 01:52:35 2023 +0000

set GCCGO=gccgo

set GOAMD64=v1

set AR=ar

set CC=gcc

set CXX=g++

set CGO_ENABLED=1

set GOMOD=NUL

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 -mthreads -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=C:\Users***\AppData\Local\Temp\go-build4262901046=/tmp/go-build -gno-record-gcc-switches

What did you do?

1. Update GOROOT/go.env, replacing GOTOOLCHAIN=auto with GOTOOLCHAIN=local.
2. Run go tool dist test -run cmd/go

What did you expect to see?

All tests passed.

What did you see instead?

Some tests failed.

=== Failed
=== FAIL: cmd/go TestScript/work_goline_order (0.15s)
=== FAIL: cmd/go TestScript/mod_go_version (0.04s)
=== FAIL: cmd/go TestScript/mod_get_future (0.08s)
=== FAIL: cmd/go TestScript/gotoolchain_modcmds (0.13s)
=== FAIL: cmd/go TestScript/gotoolchain_local (0.05s)
=== FAIL: cmd/go TestScript/goline_order (0.10s)
=== FAIL: cmd/go TestScript (0.33s)

As per CL 462198, the original intent of having go.env was this:

Various Linux distributions edit cmd/go/internal/cfg/cfg.go to change
the default settings of GOPROXY and GOSUMDB. Make it possible for
them to do this without editing the go command source code by
introducing GOROOT/go.env and moving those defaults there.

I'm trying to exercise this use case, changing the GOTOOLCHAIN default value instead (see #57001), and I can't get all tests to pass without patching a bunch of script tests.

@rsc I might be missing something, as this feature is quite new, but I'll tentatively label this as release-blocker because it is a potential blocker for Linux distros, at least it is for the one I support at Microsoft.