iOS Simulator 7.1 crash running on Yosemite with weak linked new frameworks (Symbol not found: _objc_isAuto)

Question

I have just updated to xCode 6.1 and had to reinstall my iOS 7 simulators.

I can run my app on all the simulators apart from the 5s iOS 7.1 sim. I get this crash

dyld: Symbol not found: _objc_isAuto
  Referenced from: /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation
  Expected in: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator7.1.sdk/usr/lib/libobjc.A.dylib
 in /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation
(lldb) 

What gives? Any ideas why this sim crashes?

Thanks

Paralogism

I've exactly the same issue. I think it's also related with Yosemite because prior to the upgrade it worked and than after upgrading also with xCode 6.0 didn't work for me – Mokpo

I've had it working fine with Yosemite until I updated to Xcode 6.1 this morning. – Paralogism

did u find any solution to this? – Bignonia

This also happened on iPad Air 7.1 – Kettledrum

@Paralogism I have the same issue while importing LocalAuthentication framework. Are you able to fix it? – Kettledrum

I haven't found a fix, no – Paralogism

The temporary fix is using iOS 8 simulator – Underplot

Answer 1

This issue can occur if you are building your project against the iOS 8.x SDKs and are weak linking a framework that is new to iOS 8.x and also present in OS X 10.10 and you run in the iOS 7.1 simulator.

The Xcode 6.1 Release Notes mention this issue:

If an app is weak linked against frameworks new in iOS 8 SDK and OS X 10.10 SDK, it may fail to run if the run destination is an iOS Simulator for older iOS runtimes and the host system is running OS X Yosemite. (17807439)

The issue is resolved in the updates iOS 7.1 simulator runtime that can be downloaded from Xcode 6.2 beta 4 an later (and I think possibly beta3 worked as well).

Favorable

Just wanted to note that in our case (we're weak linking the LocalAuthentication framework), we were able to run the iPhone 5 (7.1) simulator, but not the iPhone 5s (7.1) simulator. And thanks for your answer, I had been beating my head over this for a day or two now. – Trellis

Same here. Is there anything to be done to get it working again? – Paralogism

I have the same issue with the iPad Air 7.1 simulator. Seems it's related to 64bit platforms. – Redeemable

It has nothing to do with 64 bit. It has to do with weak linking. The fact that you may experience it with 64bit and not 32 bit would be because the framework you are weak linking is not available in 32bit on Yosemite. – Favorable

The only workaround is to use OS X Mavericks if you need this functionality. If this is severely impacting you, please file a bug report at bugreport.apple.com to be duped to the one referenced in the release note. – Favorable

This problem just for simulator only right, no problem on real device ? – Mm

yes. this only pertains to iOS 7.1 installed in Xcode 6.2 beta 2 and earlier running on Yosemite. – Favorable