[Xcode 7.3/7D175] libobjc crashes trying to run all tests

Number:rdar://25330746 Date Originated:24-Mar-2016 11:28 AM (GMT+9)
Status:Open Resolved:
Product:Development Tools Product Version:Xcode 7.3/7D175 OS X 10.11.4/15E65
Classification:Crash Reproducible:Always
Summary: When attempting to execute all tests, XCTest internally obtains all XCTestCase subclasses using the Objective-C runtime. It crashes here, inside the objc_copyClassList call.

I found a problematic Swift class in a mixed codebase with OBJC_PRINT_CLASS_SETUP but have yet to narrow it down to a definitive cause with that file.

Steps to Reproduce: 0. Create new iOS app project.
1. Add Swift class with unknown problem to main app target.
2. Run unit test target.

Expected Results: Tests start running.

Actual Results: Test process crashes before running any tests.

Version: Xcode 7.3/7D175
OS X 10.11.4/15E65


This doesn't occur when running individual tests, since it doesn't trigger the problematic code that finds all the tests at runtime.


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at bugreport.apple.com before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!