golang/go · error

unsupported GOOS/GOARCH pair %s/%s

Error message

unsupported GOOS/GOARCH pair %s/%s

What it means

CheckGOOSARCHPair returns this when platform.BuildModeSupported reports that the (compiler, "default", goos, goarch) tuple has no support. It gates cross-compilation targets: only GOOS/GOARCH pairs the toolchain was built to know about are allowed.

Source

Thrown at src/cmd/go/internal/work/action.go:377

func closeBuilders() {
	leakedBuilders := 0
	builderWorkDirs.Range(func(bi, _ any) bool {
		leakedBuilders++
		if err := bi.(*Builder).Close(); err != nil {
			base.Error(err)
		}
		return true
	})

	if leakedBuilders > 0 && base.GetExitStatus() == 0 {
		fmt.Fprintf(os.Stderr, "go: internal error: Builder leaked on successful exit\n")
		base.SetExitStatus(1)
	}
}

func CheckGOOSARCHPair(goos, goarch string) error {
	if !platform.BuildModeSupported(cfg.BuildContext.Compiler, "default", goos, goarch) {
		return fmt.Errorf("unsupported GOOS/GOARCH pair %s/%s", goos, goarch)
	}
	return nil
}

// NewObjdir returns the name of a fresh object directory under b.WorkDir.
// It is up to the caller to call b.Mkdir on the result at an appropriate time.
// The result ends in a slash, so that file names in that directory
// can be constructed with direct string addition.
//
// NewObjdir must be called only from a single goroutine at a time,
// so it is safe to call during action graph construction, but it must not
// be called during action graph execution.
func (b *Builder) NewObjdir() string {
	b.objdirSeq++
	return str.WithFilePathSeparator(filepath.Join(b.WorkDir, fmt.Sprintf("b%03d", b.objdirSeq)))
}

// readpkglist returns the list of packages that were built into the shared library

View on GitHub (pinned to b6b368adc5)

Solutions

1. Run 'go tool dist list' to see supported pairs and copy the exact spelling.
2. Install a Go toolchain that includes the desired port (some ports are gated by build tags or require gccgo).
3. For gccgo-only targets, build with -compiler=gccgo (CheckGOOSARCHPair queries the configured compiler).
4. Check for typos: GOARCH values are lowercase, GOOS too.

Example fix

// before
$ GOOS=linux GOARCH=x86_64 go build
// error: unsupported GOOS/GOARCH pair linux/x86_64

// after — use the correct GOARCH token
$ GOOS=linux GOARCH=amd64 go build

// Confirm a GOOS/GOARCH pair is supported before building.
func checkPair(goos, goarch string) error {
    out, err := exec.Command("go", "tool", "dist", "list").Output()
    if err != nil { return err }
    want := goos + "/" + goarch + "\n"
    if !bytes.Contains(out, []byte(want)) {
        return fmt.Errorf("%s is not a supported GOOS/GOARCH pair", want)
    }
    return nil
}

When it happens

Trigger: Calling CheckGOOSARCHPair (used by 'go build/env/list' target validation, CGO cross-compile setup, and platform checks) with a pair the installed Go toolchain doesn't ship — e.g. GOIOS=arm64 with a non-darwin GOARCH, or a misspelled GOARCH like 'amd64x'.

Common situations: Typos in GOOS/GOARCH env vars; targeting a pair that requires a separate Go installation (e.g. wasi or a custom platform); mixing GOARCH=mips with a gc toolchain that lacks that port.

Related errors

• value is neither 'auto' nor a valid bool
• build output %q already exists and is a directory
• build output %q already exists and is not an object file
• ErrHeader
• ErrWriteTooLong

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/19a8c22415af6715. Report an issue: GitHub.