macos-26-arm64 image: Xcode 26.4 RC present but iOS 26.4 Simulator runtime missing

[justSmK]

Description

The macos-26-arm64 runner image includes Xcode 26.4 RC but is missing the iOS 26.4 Simulator runtime, making it impossible to run iOS Simulator tests.

Environment

• Runner image: macos-26-arm64 (20260325.0302.1)
• Xcode: 26.4.0 Release Candidate (17E192), selected via maxim-lobanov/setup-xcode@v1 with xcode-version: latest-stable
• macOS: 26.3 (build 25D125)
• Runner version: 2.333.0

Workflow snippet

build:
  runs-on: macos-26
  steps:
    - uses: actions/checkout@v6
    - uses: maxim-lobanov/setup-xcode@v1
      with:
        xcode-version: latest-stable
    - run: bundle exec fastlane unitTestLane

Workaround

None known at this time. Manually installing the simulator runtime via xcodebuild -downloadPlatform iOS could work but significantly increases job time and may require additional disk space.

Platforms affected

• Azure DevOps
• GitHub Actions - Standard Runners
• GitHub Actions - Larger Runners

Runner images affected

• Ubuntu 22.04
• Ubuntu 24.04
• Ubuntu Slim
• macOS 14
• macOS 14 Arm64
• macOS 15
• macOS 15 Arm64
• macOS 26
• macOS 26 Arm64
• Windows Server 2022
• Windows Server 2025
• Windows Server 2025 with Visual Studio 2026

Image version and build link

https://github.com/mindbox-cloud/ios-sdk/actions/runs/23591067915/job/68848067837
https://github.com/mindbox-cloud/ios-sdk/actions/runs/23590825388/job/68787827498

Is it regression?

Yes. The previous image version worked correctly. Last successful run:
https://github.com/mindbox-cloud/ios-sdk/actions/runs/23588588392/job/68687804440

Expected behavior

The iOS Simulator runtime matching the pre-installed Xcode version should be available on the runner image, so that xcodebuild ... -destination 'platform=iOS Simulator,...' test works out of the box.

Actual behavior

The macos-26-arm64 runner image (version 20260325.0302.1) ships with Xcode 26.4 Release Candidate (17E192) but does not include the corresponding iOS 26.4 Simulator runtime. This causes xcodebuild to fail when attempting to run tests on an iOS Simulator:

xcodebuild: error: Unable to find a destination matching the provided destination specifier:
    { platform:iOS Simulator, id:0E9EC7B7-BD06-4CD5-B691-AC94F525C1C0 }

Ineligible destinations for the "Mindbox" scheme:
    { platform:iOS, id:dvtdevice-DVTiPhonePlaceholder-iphoneos:placeholder,
      name:Any iOS Device,
      error:iOS 26.4 is not installed. Please download and install the platform from Xcode > Settings > Components. }

Fastlane's scan action auto-detects and boots the simulator (iPhone 17 Pro (26.0)), but the underlying xcodebuild invocation fails because the iOS simulator platform is not actually available.

Repro steps

1. Create a workflow with runs-on: macos-26 (resolves to macos-26-arm64)
2. Select Xcode via maxim-lobanov/setup-xcode@v1 with xcode-version: latest-stable (resolves to Xcode 26.4 RC)
3. Run any xcodebuild test command targeting an iOS Simulator destination
4. Build fails with iOS 26.4 is not installed

[v-SergeiRadich]

Hi!

We are looking into it.

[justSmK]

This might be related - #13815 (comment)

[dlbuckley]

@v-SergeiRadich we are seeing this issue too. Will resolving this issue be prioritised as an out of release schedule fix, or will we have to wait until sometime next week until the fix goes in as part of the normal release schedule?

[OnurVar]

We're also affected by this. Waiting for the fix.