Xcode 7.3: Editing Storyboard File Hangs Xcode and Crashes Interface Builder Cocoa Touch Tool

Originator:wetzeal
Number:rdar://25364237 Date Originated:25-Mar-2016 02:45 PM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 7.3 (7D175)
Classification:Crash/Hang/Data Loss Reproducible:Always
 
Summary:
Trying to edit certain view controllers in the Main storyboard file in the attached project (extracted from an active project and never modified outside Xcode) causes a lock icon to appear over the Xcode UI and prevents any editing. Meanwhile, the console is filled with “Interface Builder Cocoa Touch Tool” assertion failures.

Steps to Reproduce:
1. Open the attached Xcode project
2. Open Main.storyboard
3. Attempt to edit or delete, for instance, the rightmost “String View Controller”

Expected Results:
The edits succeed, Xcode works normally

Actual Results:
A lock icon in an overlay HUD is shown, no changes are applied to the storyboard, and the system log is flooded with the following over 100 times per second:
3/25/16 2:34:50.494 PM Interface Builder Cocoa Touch Tool[12715]: assertion failed: 15E65 13E230: libxpc.dylib + 27596 [66C28065-C9DB-3C8E-926F-5A40210A6D1B]: 0x8d

Sometimes Xcode settles down and becomes responsive again until another item in the storyboard is edited. Sometimes it remains unresponsive until force quit.

Regression:
This problem appeared concurrently with Xcode 7.3, but I am also able to reproduce it on Xcode 7.2.1. I am not sure if it is related to system tools included with Xcode 7.3 that are also used by 7.2.1 or not.

Notes:
The attached storyboard includes references to classes that are not included with the project, but the problem persists in the original project as well.

Comments

Apple Developer Relations

Engineering has provided the following information regarding this issue:

You can currently work around the issue by removing property locking. This is possible through the UI (Identity inspector > Document > Lock, change to None), but awkward because you need to select the right option. Alternatively you can remove the 'propertyAccessControl="all"' string by editing the storyboard document in text format.

By wetzeal at May 6, 2016, 2:38 p.m. (reply...)

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