Xcode 26 Beta 4 Build Failures

Another interesting tidbit. I remoted into a jenkins agent node, completely reinstalled Xcode 26 beta 4.

The first build with this agent succeeded from jenkins, and the actool --version reported correctly.

The next build after that failed, and actool --version reported the ibtool incorrect information, so it's like the command line tools are corrupting themselves somehow.

Found this thread after doing a Google search. Just spent my entire day on this exact same issue:

• Same error message ("Data couldn't be read...")
• Same CI setup (Jenkins)
• Same Xcode (Xcode 26 Beta 4)

You hit the nail on the head with the comment about how there's some sort of issue with actool + ibtool.

For us, the actool that ships with Beta 4 is busted in both Jenkins builds and also in Terminal.

Xcode 26 Beta 4

In Beta 4, actool --version returns as if it's ibtool (note the "com.apple.ibtool.version" in the output):

% /Applications/Xcode-26.0.0-Beta.4.app/Contents/Developer/usr/bin/actool --version

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>com.apple.ibtool.version</key>
	<dict>
		<key>bundle-version</key>
		<string>24112</string>
		<key>short-bundle-version</key>
		<string>26.0</string>
	</dict>
</dict>
</plist>

Xcode 26 Beta 3

But in Beta 3, it's normal ("com.apple.actool.version"):

% /Applications/Xcode-26.0.0-Beta.3.app/Contents/Developer/usr/bin/actool --version

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>com.apple.actool.version</key>
    <dict>
        <key>bundle-version</key>
        <string>24093.9</string>
        <key>short-bundle-version</key>
        <string>26.0</string>
    </dict>
</dict>
</plist>

Conclusion

In the end, we concluded that there's something just fundamentally busted about actool in Beta 4.

Dropped back to Beta 3 and everything works.

Really hoping to run "actool --version" in the upcoming Beta 5 and see it work correctly. :-)

I'm here to report that I'm running into exactly the same. Interesting enough: it only happens to some of my xcodebuild commands, even though they're exactly the same apart from the package they're testing.

So, I have a self-hosted GitHub Actions pipeline. The first package tested runs into this error:

/Applications/Xcode-26.0.0-Beta.4.app/Contents/Developer/usr/bin/xcodebuild -scheme SimulatorCapturing -destination platform=macOS -resultBundlePath /Users/avanderlee/Developer/actions-runner/_work/RocketSim/RocketSim/fastlane/../build/reports/SimulatorCapturing.xcresult -parallel-testing-enabled NO CI=true RECORD_SNAPSHOTS= build test

But the next steps don't. This is an example of a another step that succeeds:

[13:27:40]: ▸     /Applications/Xcode-26.0.0-Beta.4.app/Contents/Developer/usr/bin/xcodebuild -scheme ShellKit -destination platform=macOS -resultBundlePath /Users/avanderlee/Developer/actions-runner/_work/RocketSim/RocketSim/fastlane/../build/reports/ShellKit.xcresult -parallel-testing-enabled NO CI=true RECORD_SNAPSHOTS= build test

For me as well: this didn't happen with an older Xcode beta.

I've also reported this in the Feedback Assistant: FB19231144

Update: I managed to fix it by manually calling:

/Applications/Xcode-26.0.0-Beta.4.app/Contents/Developer/usr/bin/actool --version --output-format xml1

In a step before the actual xcodebuild step. It's almost like it caches some kind of state that allows future calls into it to succeed.

We're seeing this issue also, on self-hosted CircleCI runners.

We are seeing this issue also

Here as well in Jenkins

We're taking a look. @AvdLee, thank you for filing FB19231144!

— Ed Ford,  DTS Engineer

Also having this periodically since update from Beta 3.

Running this does not seem to help prior the build: xcrun actool --version --output-format xml1

CI is switching between Xcode 16.4 and Xcode 26.0 Beta 4 randomly, but using separate directed data directories.

Also experiencing this problem. Seems to be still there with Xcode 26 Beta 5.

Confirmed, still happening with beta 5. I filed a new feedback against beta 5: FB19447083

We are also seeing this in beta 5 still. Over Github actions it succeeds sometimes and fails other times, but no build ever fails when run on the runner in command line manually.

This is resolved with Xcode 26 beta 6.

— Ed Ford,  DTS Engineer