I updated my computer to the latest beta that was released to developers last night and the same project that was compiling fine yesterday night now fails due to a supposed .xib/.storyboard error.
I have tried cleaning the project, downloading a previous version off of github, etc.. and yet the project still gives me the following error. "Failed to communicate with Interface Builder" as well as Command /Applications/Xcode.app/Contents/Developer/usr/bin/ibtool failed with exit code 255. Literally nothing was changed with the .storyboard file or anything remotely related to it.
What's more is that trying to open any .xib/.storyboard file (even the launch screen xib which I haven't touched leads to Xcode crashing which leads me to think this has nothing to do with me.)
Anyone else experiencing this? Any advice or temporary fixes?
Update: Trying to run anything on the simulator causes it to crash continuously or hang with the following error message: "Springboard quit unexpectedly"
Update 2: Playgrounds are unusable but do not crash. Also, these lads seem to be in the same boat as we are. https://forums.developer.apple.com/thread/13170
This is why we can't have nice things, Apple.
A workaround was found thanks to "lembacon" on the Apple Developer Forums.
In Terminal:
cd /Applications/Xcode-beta.app (or wherever your Xcode 7 beta 4 is located)
cd Contents/Developer/Platforms/iPhoneSimulator.platform
cd Developer/SDKs/iPhoneSimulator.sdk/usr/lib
sudo mv dyld_sim dyld_sim.orig
Seems to work for iOS projects but watchOS is iffy.
EDIT: watchOS solution:
cd /Applications/Xcode-beta.app (or wherever your Xcode 7 beta 4 is located)
cd Contents/Developer/Platforms/WatchSimulator.platform
cd Developer/SDKs/WatchSimulator.sdk/usr/lib
sudo mv dyld_sim dyld_sim.orig
Another Edit: As mentioned by sciasxp, this also works for 6.4. Hopefully we'll get new iOS and Xcode betas soon that permanently fix this.
Another Another Edit: A new iOS beta is out today, as well as a new Xcode beta. This issue should be resolved.
There is one weird fix :
Reinstall Beta 5 by downloading and running the following directly from Apple's CDN. This will restore Xcode but you will loose sound :)
Xcode 7.0 beta 5 is out with support for El Capitan beta 6.
Xcode 7 beta 5 resolves issues with building iOS projects and running the iOS simulator on OS X El Capitan beta 6. (22089926)
Running xcode 7.0.1 on ElCapitan with all updates installed and xcode is quitting often as above but not quire often enough that I cant develop for it. Seems to occur when setting constraints and positions in storyboard. iMac is latest and restarted at least once a week as off on weekends so stable as I can make it.
As with every release of Apple we just need to wait for the updates for xcode and or ElCapitan to fix it.
So rule is to save/build often to save code before playing around with constraints as its liable to just quit on you.
It's documented in the El Capitan Beta 6 Release Notes, so you cannot blame Apple if you didn't read them.
Known Issues
- Xcode 6.x has known compatibility issues when run on OS X El Capitan. It is strongly encouraged that you use Xcode 7 when running on OS X El Capitan.
EDIT Mostly the tone of this answer was brought about by the "This is why we can't have nice things, Apple." statement in question, implying the OP thinks he has a god-given right to use beta operating systems without impunity.
来源：https://stackoverflow.com/questions/31803585/xcode-6-4-7-crashing-after-el-capitan-beta