Troubleshooting iOS and OSX builds

There are common problems you might run into during the initial setup of your CI/CD setup with CircleCI or even issues that only occur when your project has grown to a certain size.

Xcode Toolchain errors

xcodebuild exit code 65

There are plenty of reasons why exit code 65 could be thrown, as it is a general error returned for bad user input. Sometimes that is not the case though, since all your builds run in a container your builds also have to share system resources with other builds. Exit code 65 is mostly the issue of a lack of enough CPU power to launch the iOS simulator in time for the test to run once xcodebuild’S test action is called, and the tests simply time out. A way to mitigate this is to launch the iOS simulator as a part of your dependencies block in your CircleCI configuration file.

    - xcrun instruments -w 'E8DD285C-51EE-4DB5-B326-7E927686EC36' || true 

This will launch the simulator just like it would if you’d hit CMD + R on your machine in Xcode, and once your tests are supposed to start the iOS simulator is immediately available.

A full list of UUIDs for iOS simulators is available here.