Unknown command line argument '-aarch64-use-tbi'

[paveloom]

Description

I'm hitting the following error while trying to run xtool dev build or xtool dev run:

$ ~/Playground/xtool/Linux/packages/xtool-x86_64.AppImage dev build
Planning...
[1/1] Planning build
Building for debugging...
error: emit-module command failed with exit code 1 (use -v to see invocation)
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?

Error: exit(1)

Same for the AppImage built from main and for the AppImage from the latest release (v1.16.1).

Environment

Host OS (macOS/Linux/WSL): Linux

Host OS version:

Gentoo Base System release 2.18
DISTRIB_ID="Gentoo"
NAME='Gentoo'
ID='gentoo'
PRETTY_NAME='Gentoo Linux'
VERSION='2.18'
VERSION_ID='2.18'
HOME_URL='https://www.gentoo.org/'
SUPPORT_URL='https://www.gentoo.org/support/'
BUG_REPORT_URL='https://bugs.gentoo.org/'
ANSI_COLOR='1;32'

iOS device version:
15.8.7

Swift version:
Swift version 6.2.4 (swift-6.2.4-RELEASE)

SDK version:
iPhoneOS26.0.sdk

[kabiroberai]

can you try updating to Swift 6.3 + the iOS 26.4 SDK?

[paveloom]

Same. That's what I started with, actually.

Details

$ swift --version
Swift version 6.3 (swift-6.3-RELEASE)
Target: x86_64-unknown-linux-gnu
$ mkdir temp
$ TMPDIR=temp ~/Playground/xtool/Linux/packages/xtool-x86_64.AppImage sdk Xcode_26.4.1_Universal.xip
[Downloading toolset] 100%
[Extracting XIP] 100%
[Installing SDKs] 100%
[Cleaning up]
[Finalizing SDKs]
- iPhoneOS26.4.sdk
- iPhoneSimulator26.4.sdk
- MacOSX26.4.sdk
[Writing metadata]
Swift SDK bundle at `/home/paveloom/Playground/xtool-test/temp/sh.xtool/tmp-DarwinSDKBuild-2CBCDD6D-B50E-440D-98A6-B1E8FA74A342/DarwinSDKBuild/darwin.artifactbundle` successfully installed as darwin.artifactbundle.
$ swift sdk configure darwin arm64-apple-ios --show-configuration | grep -o 'iPhoneOS[0-9.]*\.sdk$'
iPhoneOS26.4.sdk
$ ~/Playground/xtool/Linux/packages/xtool-x86_64.AppImage new HelloWorld
Creating package: HelloWorld
Creating Package.swift
Creating xtool.yml
Creating .gitignore
Creating .sourcekit-lsp/config.json
Creating Sources/HelloWorld/HelloWorldApp.swift
Creating Sources/HelloWorld/ContentView.swift

Finished generating project HelloWorld. Next steps:
- Enter the directory with `cd HelloWorld`
- Build and run with `xtool dev`
$ cd HelloWorld
$ ~/Playground/xtool/Linux/packages/xtool-x86_64.AppImage dev
Planning...
Building for debugging...
error: emit-module command failed with exit code 1 (use -v to see invocation)
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?
swift (LLVM option parsing): Unknown command line argument '-aarch64-use-tbi'.  Try: 'swift (LLVM option parsing) --help'
swift (LLVM option parsing): Did you mean '--target-abi'?

Error: exit(1)

There is an old snippet of hidden options of swiftc that includes aarch64-use-tbi, however my swiftc doesn't have that option. In fact, I didn't even find where it comes from during xtool dev's execution. It's neither in the xtool's code nor in the files of the generated project.

swiftc-options.txt