cmd/compile: -trimpath and -json=0,file flags may lead to invalid "file://" URLs

[seankhliao]

gopls version

Build info
----------
golang.org/x/tools/gopls v0.23.0
    golang.org/x/tools/gopls@v0.23.0 h1:Dn6mf9WXu9iLnTftDDMb9wV0c6Se7PjzEMqP0LEe08Y=
    github.com/BurntSushi/toml@v1.6.0 h1:dRaEfpa2VI55EwlIW72hMRHdWouJeRF7TPYhI+AUQjk=
    github.com/fatih/camelcase@v1.0.0 h1:hxNvNX/xYBp0ovncs8WyWZrOrpBNub/JfaMvbURyft8=
    github.com/fatih/gomodifytags@v1.17.1-0.20250423142747-f3939df9aa3c h1:dDSgAjoOMp8da3egfz0t2S+t8RGOpEmEXZubcGuc0Bg=
    github.com/fatih/structtag@v1.2.0 h1:/OdNE99OxoI/PqaW/SuSK9uxxT3f/tcSZgon/ssNSx4=
    github.com/fsnotify/fsnotify@v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
    github.com/google/jsonschema-go@v0.4.3 h1:/DBOLZTfDow7pe2GmaJNhltueGTtDKICi8V8p+DQPd0=
    github.com/modelcontextprotocol/go-sdk@v1.6.0 h1:PPLS3kn7WtOEnR+Af4X5H96SG0qSab8R/ZQT/HkhPkY=
    github.com/segmentio/asm@v1.2.1 h1:DTNbBqs57ioxAD4PrArqftgypG4/qNpXoJx8TVXxPR0=
    github.com/segmentio/encoding@v0.5.4 h1:OW1VRern8Nw6ITAtwSZ7Idrl3MXCFwXHPgqESYfvNt0=
    github.com/yosida95/uritemplate/v3@v3.0.2 h1:Ed3Oyj9yrmi9087+NczuL5BwkIc4wvTb5zIM+UJPGz4=
    golang.org/x/exp/typeparams@v0.0.0-20260611194520-c48552f49976 h1:GTD/WuaexTazIG/SxLOz4rEKZPDVilmVVC2nz4xhwfE=
    golang.org/x/mod@v0.37.0 h1:vF1DjpVEshcIqoEaauuHebaLk1O1forxjxBaVn884JQ=
    golang.org/x/oauth2@v0.36.0 h1:peZ/1z27fi9hUOFCAZaHyrpWG5lwe0RJEEEeH0ThlIs=
    golang.org/x/sync@v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
    golang.org/x/sys@v0.46.0 h1:noSf2Fq6F8DBgS+LysIkx7rIExoNHJsxOAtPp4rthXw=
    golang.org/x/telemetry@v0.0.0-20260625142307-59b4966ccb57 h1:nwGZBCt+FnXUrGsj5vjzAsEmkcaFvd82BbOjECiFYZc=
    golang.org/x/text@v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE=
    golang.org/x/tools@v0.47.1-0.20260707181000-a299dadba899 h1:5O28oLQxJ1jif5UNdi9OULXCd4g3rsy3xkECh96fnf8=
    golang.org/x/vuln@v1.4.0 h1:FpmTZiV4PyqY3lFfuCkz1JftEXb/+8M2NEkjJM5TF4g=
    honnef.co/go/tools@v0.8.0-rc.1 h1:wqMm2kjcEXMOr+6yau+pdKqJKe6l2N1aKPkpini+Kzk=
    mvdan.cc/gofumpt@v0.10.0 h1:yGGpRS2pBN2OQIi7b21IXknJna7faPkFaVfHLrN6Euo=
    mvdan.cc/xurls/v2@v2.6.0 h1:3NTZpeTxYVWNSokW3MKeyVkz/j7uYXYiMtXRUfmjbgI=
go: go1.28-devel_f0c78119ea 2026-07-15 14:04:28 -0700

go env

AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='0'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE=''
GOAMD64='v3'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN='/home/user/.data/go/bin'
GOCACHE='/home/user/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/home/user/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS='-trimpath "-ldflags=-s -w" -vet=all'
GOGCCFLAGS='-fPIC -m64 -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3531964740=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/home/user/sdk/go/src/go.mod'
GOMODCACHE='/home/user/.data/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPACKAGESDRIVER=''
GOPATH='/home/user/.data/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/home/user/sdk/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='on'
GOTELEMETRYDIR='/home/user/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='path'
GOTOOLDIR='/home/user/sdk/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.28-devel_f0c78119ea 2026-07-15 14:04:28 -0700'
GOWORK=''
PKG_CONFIG='pkg-config'

What did you do?

open $GOROOT/src/regexp/regexp.go
toggle code action to show compiler optimizations

What did you see happen?

vim.schedule callback: /usr/share/nvim/runtime/lua/vim/uri.lua:104: URI must contain a scheme:
stack traceback:
        [C]: in function 'error'
        /usr/share/nvim/runtime/lua/vim/uri.lua:104: in function 'uri_to_fname'
        /usr/share/nvim/runtime/lua/vim/lsp/diagnostic.lua:238: in function 'handle_diagnostics'
        /usr/share/nvim/runtime/lua/vim/lsp/diagnostic.lua:266: in function 'handler'
        /usr/share/nvim/runtime/lua/vim/lsp/client.lua:1323: in function '_notification'
        /usr/share/nvim/runtime/lua/vim/lsp/client.lua:470: in function 'fn'
        [string "vim/_core/editor"]:273: in function <[string "vim/_core/editor"]:272>

What did you expect to see?

compiler opts?

Editor and settings

NVIM v0.12.4
Build type: RelWithDebInfo
LuaJIT 2.1.1784360928

vim.lsp.config("gopls", {
    -- https://github.com/golang/tools/tree/master/gopls
    cmd = { "gopls" },
    -- cmd = { "gopls", "-rpc.trace", "-logfile=/home/user/gopls.log" },
    filetypes = { "go", "gomod", "gowork", "gotmpl" },
    root_markers = { "go.mod", "go.sum", "go.work", ".git" },
    settings = {
        gopls = {
            gofumpt = true,
            staticcheck = true,
            templateExtensions = { "gotmpl" },
            vulncheck = "Imports",
            analyses = {
                shadow = true,
                unusedwrite = true,
            },
        },
    },
    on_init = function(client)
        local path = client.workspace_folders[1].name
        if path:find("/sdk/") then
            -- disable gofumpt when working on Go project repos
            client.config.settings.gopls.gofumpt = false
        end
    end,
})
vim.lsp.enable("gopls")

https://git.liao.dev/dotconfig/tree/nvim/init.lua#n253

Logs

rpc trace: gopls.log

[gabyhelp]

Related Issues

• x/tools/gopls: vim-installed gopls@v0.14.2 does not work (but command-line installed gopls@v0.14.2 is OK) #64889 (closed)
• x/tools/gopls: returns invalid comment on hover #79146 (closed)
• x/tools/gopls: <DESCRIBE THE PROBLEM> #67963 (closed)
• x/tools/gopls: <DESCRIBE THE PROBLEM> #67964 (closed)
• x/tools/gopls: <DESCRIBE THE PROBLEM> #67965 (closed)
• x/tools/gopls: <DESCRIBE THE PROBLEM> #67966 (closed)
• x/tools/gopls: Disabled analyzers gets enabled by default #78600 (closed)
• x/tools/gopls: Definition: does not treat doc link followed by colon as a reference #75925 (closed)
• x/tools/gopls: gopls sends verbose error messages via $/progress instead of window/showMessage #78273
• x/tools/gopls: disabling semantic token types in ui.semanticTokenTypes can break token locations #78269 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[adonovan]

I think the problem is in the compiler.

$ cat /tmp/repro/main.go
package main

func InlineMe(a int) *int {
        return &a
}

func Caller() *int {
        return InlineMe(42)
}

$ go tool compile -p=main -trimpath "/tmp/repro=>repro" -json=0,/tmp/repro/out /tmp/repro/main.go

$ grep file://[^/]  /tmp/repro/out/main/main.json 
..."uri":"file://repro/main.go"...

Observe the "file://" prefix with two (not three) slashes; this is not a valid file URI, and it came out of the compiler.

[dominikh]

(To be incredibly pedantic, that is a valid file URI, but it refers to the file /main.go on the host repro)