fyne-io/fyne · error

unknown GOARCH: %q

Error message

unknown GOARCH: %q

What it means

While preparing the clang environment for iOS/iosimulator targets, the vendored mobile tool iterates every architecture in the target list and maps it to an Xcode SDK. Only arm (GOARM=7), arm64, 386 and amd64 (both simulator) are handled; any other GOARCH reaches the default branch and panics.

Source

Thrown at cmd/fyne/internal/mobile/env.go:201

		var err error
		var clang, cflags string
		switch arch {
		case "arm":
			env = append(env, "GOARM=7")
			fallthrough
		case "arm64":
			if buildTarget == "ios" {
				clang, cflags, err = envClang("iphoneos")
				cflags += " -miphoneos-version-min=" + buildIOSVersion
			} else { // iossimulator
				clang, cflags, err = envClang("iphonesimulator")
				cflags += " -mios-simulator-version-min=" + buildIOSVersion
			}
		case "386", "amd64":
			clang, cflags, err = envClang("iphonesimulator")
			cflags += " -mios-simulator-version-min=" + buildIOSVersion
		default:
			panic(fmt.Errorf("unknown GOARCH: %q", arch))
		}
		if err != nil {
			return err
		}

		if bitcodeEnabled {
			cflags += " -fembed-bitcode"
		}

		os := "ios"
		if before116 {
			os = "darwin"
		}
		env = append(
			env,
			"GOOS="+os,
			"GOARCH="+arch,
			"CC="+clang,

View on GitHub (pinned to 8860ee95c3)

Solutions

1. Use supported targets: plain ios (arm64+arm) or iossimulator (amd64/386); drop the unsupported arch from -target
2. Run 'unset GOARCH GOARM GOOS' before 'fyne package' so a leaked environment variable cannot poison the target
3. Update fyne - architectures are added to the supported set as Xcode gains them

Example fix

# before
fyne package -os ios -target ios/riscv64

# after
fyne package -os ios

// Pre-flight: validate the -target architecture list before invoking the packaging tool.
var supportedIOSArchs = map[string]bool{"arm": true, "arm64": true, "386": true, "amd64": true}
func validTarget(archs []string) error {
    for _, a := range archs {
        if !supportedIOSArchs[a] { return fmt.Errorf("unsupported target arch %q; use ios or iossimulator defaults", a) }
    }
    return nil
}

When it happens

Trigger: Packaging for an Apple target with an architecture outside {arm, arm64, 386, amd64} in the list, e.g. 'fyne package -os ios -target ios/riscv64', or a GOARCH value leaked into the environment when custom tooling reuses this code path.

Common situations: A stale exported GOARCH in the shell/CI session; typo'd -target values; building for a new architecture before the vendored tool supports it.

Related errors

• unhandled token type: %T %+v
• unsupported GOARCH:
• out of touchIDs
• encountered empty values slice
• TODO only know how to handle DataIntDec type here

AI-assisted analysis of fyne-io/fyne@8860ee95c3 (2026-08-15). Data as JSON: /api/errors/d9def59ca144cb7d. Report an issue: GitHub.