GOEXPERIMENT breaks Go version detection

[artyom]

test1 ¶ staticcheck -debug.version
staticcheck 2024.1 (0.5.0)

Compiled with Go version: go1.23.0 X:rangefunc
Main module:
    honnef.co/go/tools@v0.5.0 (sum: h1:29uoiIormS3Z6R+t56STz/oI4v+mB51TSmEOdJPgRnE=)
Dependencies:
    github.com/BurntSushi/toml@v1.4.1-0.20240526193622-a339e1f7089c (sum: h1:pxW6RcqyfI9/kWtOwnv/G+AzdKuy2ZrqINhenH4HyNs=)
    golang.org/x/exp/typeparams@v0.0.0-20231108232855-2478ac86f678 (sum: h1:1P7xPZEwZMoBoz0Yze5Nx2/4pxj6nw9ZqHWXqP0iRgQ=)
    golang.org/x/mod@v0.17.0 (sum: h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=)
    golang.org/x/sync@v0.7.0 (sum: h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=)
    golang.org/x/tools@v0.21.1-0.20240531212143-b6235391adb3 (sum: h1:SHq4Rl+B7WvyM4XODon1LXtP7gcG49+7Jubt1gWWswY=)

test1 ¶ go version
go version go1.23.0 darwin/arm64
test1 ¶ go env
GO111MODULE=''
GOARCH='arm64'
GOBIN=''
GOCACHE='/Users/artyom/Library/Caches/go-build'
GOENV='/Users/artyom/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT='rangefunc'
GOFLAGS='-ldflags=-w -trimpath'
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMODCACHE='/Users/artyom/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/artyom/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/Users/artyom/Library/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/Users/artyom/Library/go/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.23.0'
GODEBUG=''
GOTELEMETRY='on'
GOTELEMETRYDIR='/Users/artyom/Library/Application Support/go/telemetry'
GCCGO='gccgo'
GOARM64='v8.0'
AR='ar'
CC='clang'
CXX='clang++'
CGO_ENABLED='1'
GOMOD='/tmp/test1/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/lb/3rk8rqs53czgb4v35w_342xc0000gn/T/go-build3092433690=/tmp/go-build -gno-record-gcc-switches -fno-common'

To reproduce:

$ mkdir /tmp/test1
$ cd /tmp/test1

$ go mod init foo
$ cat go.mod
module foo

go 1.23.0

$ cat >main.go <<EOF
package main
func main() {}
EOF

$ staticcheck 
-: module requires at least go1.23.0, but Staticcheck was built with go1.23 (compile)

[dominikh]

I'm failing to reproduce this. Are you sure that you're running the same staticcheck executable both times?

[artyom]

Yes, the one installed with go install honnef.co/go/tools/cmd/staticcheck@latest:

test1 ¶ go version -m $(which staticcheck)
/Users/artyom/go/bin/staticcheck: go1.23.0 X:rangefunc
    path    honnef.co/go/tools/cmd/staticcheck
    mod honnef.co/go/tools  v0.5.0  h1:29uoiIormS3Z6R+t56STz/oI4v+mB51TSmEOdJPgRnE=
    dep github.com/BurntSushi/toml  v1.4.1-0.20240526193622-a339e1f7089c    h1:pxW6RcqyfI9/kWtOwnv/G+AzdKuy2ZrqINhenH4HyNs=
    dep golang.org/x/exp/typeparams v0.0.0-20231108232855-2478ac86f678  h1:1P7xPZEwZMoBoz0Yze5Nx2/4pxj6nw9ZqHWXqP0iRgQ=
    dep golang.org/x/mod    v0.17.0 h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=
    dep golang.org/x/sync   v0.7.0  h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
    dep golang.org/x/tools  v0.21.1-0.20240531212143-b6235391adb3   h1:SHq4Rl+B7WvyM4XODon1LXtP7gcG49+7Jubt1gWWswY=
    build   -buildmode=exe
    build   -compiler=gc
    build   -trimpath=true
    build   DefaultGODEBUG=asynctimerchan=1,gotypesalias=0,httpservecontentkeepheaders=1,tls3des=1,tlskyber=0,x509keypairleaf=0,x509negativeserial=1
    build   CGO_ENABLED=1
    build   GOARCH=arm64
    build   GOEXPERIMENT=rangefunc
    build   GOOS=darwin
    build   GOARM64=v8.0

test1 ¶ /Users/artyom/go/bin/staticcheck  
-: module requires at least go1.23.0, but Staticcheck was built with go1.23 (compile)
1 test1 ¶ cat go.mod main.go 
module foo

go 1.23.0
package main
func main() {}

[artyom]

I unset GOEXPERIMENT=rangefunc like so:

test1 ¶ go env -u GOEXPERIMENT
test1 ¶ go env GOEXPERIMENT

Reinstalled:

test1 ¶ go install honnef.co/go/tools/cmd/staticcheck@latest

test1 ¶ go version -m $(which staticcheck) | grep GOEXPERIMENT
1 test1 ¶ 

And now it succeeds:

test1 ¶ staticcheck ; echo $?                                 
0

So it looks like the bug only happens with GOEXPERIMENT=rangefunc (not sure yet either env-dependent or how the binary was buit).

The bug only happens when running staticcheck built with GOEXPERIMENT=rangefunc (regardless of the env it then used in)

[dominikh]

Thank you, I can reproduce it now.

[dominikh]

Barring any other issues, I'll cut a new release later today that includes this fix.