xcodebuild hangs with multiple concurrent invocations

Originator:ali.rantakari
Number:rdar://25449580 Date Originated:31-Mar-2016
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 7.3 (7D175)
Classification:Bug Reproducible:Sometimes
 
Summary:
Xcodebuild often hangs when multiple instances of the xcodebuild process are running concurrently with the following arguments:

xcodebuild -project PROJECT -alltargets -showBuildSettings

Steps to Reproduce:
1. Install Xcode 7.3
2. Extract the attached archive into a temporary folder
3. Open Terminal.app
4. CD into the folder where you extracted the archive
5. Execute `test.py` (it will try to reproduce the bug by running multiple instances of xcodebuild with the above mentioned arguments concurrently)
6. If `test.py` exists successfully and does not hang, try executing it again many times — at some point it should hang (this is a concurrency bug, after all)

Expected Results:
None of the xcodebuild processes should not hang

Actual Results:
Often some of the xcodebuild processes will hang

Version:
Xcode 7.3 (7D175)
OS X 10.11.1 (15B42)

Notes:
Adding the arguments CODE_SIGNING_ALLOWED=NO and CODE_SIGNING_REQUIRED=NO seem to work around this issue, which indicates that the hang is due to some feature in xcodebuild related to code signing.

Configuration:
Occurs with Xcode 7.3, for Xcode projects that contain more than one target.

Attachments:
'XcodebuildConcurrentHangRepro.zip' was successfully uploaded.

Comments


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