cmd/link: can't dynamically import static CFString constants using the internal linker
- Dominant language
- Go
- Stars
- 139k
- Forks
- 19.4k
- PR merge metrics
- PR metrics pending
Description
### Go version
go version devel go1.24-2b3b5305c6 Fri Jan 24 12:35:21 2025 +0100 darwin/arm64
### Output of `go env` in your module/workspace:
```shell
AR='ar'
CC='clang'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='clang++'
GCCGO='gccgo'
GO111MODULE=''
GOARCH='arm64'
GOARM64='v8.0'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/Users/qmuntaldiaz/Library/Caches/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/Users/qmuntaldiaz/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/6_/bk27w0c510ld88800_hfj6j00000gn/T/go-build3109590806=/tmp/go-build -gno-record-gcc-switches -fno-common'
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMOD='/Users/qmuntaldiaz/code/golang-go/src/go.mod'
GOMODCACHE='/Users/qmuntaldiaz/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/qmuntaldiaz/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/Users/qmuntaldiaz/code/golang-go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='on'
GOTELEMETRYDIR='/Users/qmuntaldiaz/Library/Application Support/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/Users/qmuntaldiaz/code/golang-go/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='devel go1.24-2b3b5305c6 Fri Jan 24 12:35:21 2025 +0100'
GOWORK=''
PKG_CONFIG='pkg-config'
```
### What did you do?
Execute the following code with `go run -ldflags=-linkmode=internal .`.
```go
package main
// #cgo LDFLAGS: -framework CoreFoundation
// #include
import "C"
import "unsafe"
//go:cgo_import_dynamic main._kCFErrorUnderlyingErrorKey kCFErrorUnderlyingErrorKey "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
var _kCFErrorUnderlyingErrorKey byte
var kCFErrorUnderlyingErrorKey = C.CFStringRef(unsafe.Pointer(*(*uintptr)(unsafe.Pointer(&__kCFErrorUnderlyingErrorKey))))
func main() {
out := make([]byte, C.CFStringGetLength(kCFErrorUnderlyingErrorKey))
var used C.CFIndex
C.CFStringGetBytes(kCFErrorUnderlyingErrorKey, C.CFRange{0, C.CFIndex(len(out))},
C.kCFStringEncodingUTF8, 0, 0,
(*C.UInt8)(&out[0]), C.CFIndex(len(out)), &used)
want := "NSUnderlyingError"
got := string(out[:used])
if got != want {
println("got", got, "want", want)
panic("FAIL")
}
}
```
Note that I'm using some C functions (`C.CFStringGetLength` and `C.CFStringGetBytes `) to make the reproducer self-contained. What I really do is define all external functions using `cgo_import_dynamic`, which doesn't modify the failure described here.
@golang/compiler
### What did you see happen?
```
main.init: program too large, address relocation distance = -4295397376
```
### What did you expect to see?
The execution succeeds.
Contributor guide
Research direction
Reproduce the failure on darwin/arm64 with the provided program and -ldflags=-linkmode=internal. Start at the internal linker handling of cgo_import_dynamic references to static CFString constants; done means the program links and executes successfully with the expected NSUnderlyingError output.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- go
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 42/100