SourceKittenFramework Fatal error only with Xcode 26

[renaudjennymonese]

Troubleshooting

• I've searched discuss.bitrise.io for possible solutions.
• Which version of the step is effected? 6.2.2
• Is the issue reproducible with the latest version? YES
• Does the issue happen sporadically, or every time? EVERY TIME
• Is the issue reproducible locally by following our local debug guide? NO

Useful information

• FAQ
• devcenter.bitrise.io

Issue description

I'm trying to use Xcode 26 machines with my project. Locally, no problems to build and run the tests with Xcode 26.x (currently using 26.1.1 and no issues locally).
The same exact code works totally fine on Bitrise with Xcode 16.4 (cf this build).
But this one for instance gives me the error:

Failed to execute Step: command failed with exit status 65 (xcodebuild "-workspace" "/Users/vagrant/git/Monese.xcworkspace" "-scheme" "dev" "test" "-destination" "id=9E440ECB-9E89-4846-83E4-EE6317112761" "-resultBundlePath" "/var/folders/f6/wf2hj3cj75qdwmt5rn814r_00000gn/T/XCUITestOutput3336297154/Test-dev.xcresult" "-retry-tests-on-failure" "-test-iterations" "3" "-xcconfig" "/var/folders/f6/wf2hj3cj75qdwmt5rn814r_00000gn/T/1742082581/temp.xcconfig"): SourceKittenFramework/library_wrapper.swift:39: Fatal error: Loading sourcekitd.framework/Versions/A/sourcekitd failed (exit code: 1)

I've tried many things, including this via a script before the Xcode step: realm/SwiftLint#1466 (comment) This seems to be the magic thing that fixes the issue. But unfortunately it doesn't work for me...

Bitrise info

• Build URL: https://app.bitrise.io/build/f8fdbe63-f338-4aa3-a073-75271b1c941b
• Bitrise Support enabled: YES
• Log:

Details

Failed to execute Step: command failed with exit status 65 (xcodebuild "-workspace" "/Users/vagrant/git/Monese.xcworkspace" "-scheme" "dev" "test" "-destination" "id=9E440ECB-9E89-4846-83E4-EE6317112761" "-resultBundlePath" "/var/folders/f6/wf2hj3cj75qdwmt5rn814r_00000gn/T/XCUITestOutput3336297154/Test-dev.xcresult" "-retry-tests-on-failure" "-test-iterations" "3" "-xcconfig" "/var/folders/f6/wf2hj3cj75qdwmt5rn814r_00000gn/T/1742082581/temp.xcconfig"): SourceKittenFramework/library_wrapper.swift:39: Fatal error: Loading sourcekitd.framework/Versions/A/sourcekitd failed (exit code: 1)
  

Steps to reproduce

1. Select the default Machine on Bitrise to use Xcode 26 or greater
2. Observe new builds to fail for the reason mentioned above in the Xcode test step
3. Go back to Xcode 16.4 Machine and same build will be successful without changing anything else