Xcode9b5: Interface Builder Cocoa Touch Tool nomming 130% CPU

Number:rdar://33815421 Date Originated:8/9/2017
Status:Open Resolved:
Product:Developer Tools Product Version:Version 9.0 beta 5 (9M202q)
Classification:Serious Bug Reproducible:Didn't Try

I noticed my laptops fans had revved up, and noticed two "Interface Builder Cocoa Touch Tool" processes each at 150%, and had been running for awhile.

Attached to this (hopefully) are two samples taken from Activity Monitor.  Also attached is a screenshot. And the storyboard.

What may have triggered it was this sequence of events (I haven't tried to repro yet):

* Edit a file
* Cmd-shift-O to go to the storyboard. Make an edit.
* Cmd-shift-O to go to another file.  Remembered I forgot to save. (thanks to rdar://33393295, I've lost lots of data, so I really hammer the cmd-S these days)
* Go back a history in the editor (command-control-left-arrow)
* Before the editor fully reloaded, cmd-S and then return with command-control-right arrow

I've got a sysdiagnose, but it'll take a long time to upload, so filing this now with the smaller attachments, and will add a dropbox link (because rdar://30364703)

Steps to Reproduce:
see summary

Expected Results:
see summary

Observed Results:
see summary

Version 9.0 beta 5 (9M202q)
10.12.6 (16G29)

Some ranchers have seen ibtool lockups with Cocoa desktop projects in b4. Dunno if there's any relationship.



I have got the same problem. Don't want to use. Made my mac so hot all the time. I am actually searching anyone has got the same problem.

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