Xcode 6 linker error - Undefined symbols for archi

Question

After upgrading to Xcode 6 beta 7 (and now still with Xcode 6 GM) I am unable to link my Swift app. I receive errors such as:

Undefined symbols for architecture armv7: "_swift_stdlib_compareNSStringDeterministicUnicodeCollation", referenced from:

...

ld: symbol(s) not found for architecture armv7 clang: error: linker command failed with exit code 1 (use -v to see invocation)

I have seen the other SO posts that recommend deleting the Derived Data folder and/or using the Clean Build Folder option to get past this error, but that solution didn't help at all in my case. Nothing has changed about my code or the CocoaPods I'm using since Xcode 6 beta 5 which is the last time it worked.

Any ideas?

EDIT:

A full posting of the error log:

Undefined symbols for architecture arm64: "_swift_stdlib_compareNSStringDeterministicUnicodeCollation", referenced from: TFC12MyProject21BarcodeViewController13captureOutputfS0_FTGSQCSo15AVCaptureOutput_24didOutputMetadataObjectsGSQGSaPSs9AnyObject___14fromConnectionGSQCSo19AVCaptureConnection__T_ in BarcodeViewController.o "__TFSs21_arrayConditionalCastU___FGSaQ__GSqGSaQ0_", referenced from: TFC12MyProject27SessionsTableViewController17viewWillDisappearfS0_FSbT_ in SessionsTableViewController.o "__TFSs15_arrayForceCastU___FGSaQ__GSaQ0", referenced from: __TFC12MyProject7RestApi12tokenMappingfS0_FT_CSo15RKEntityMapping in RestApi.o __TFC12MyProject28AttendeesTableViewControllerg24fetchedResultsControllerCSo26NSFetchedResultsController in AttendeesTableViewController.o __TFC12MyProject27SessionsTableViewControllerg24fetchedResultsControllerCSo26NSFetchedResultsController in SessionsTableViewController.o __TFC12MyProject21BarcodeViewController13startScanningfS0_FT_Sb in BarcodeViewController.o "__TFSs26_forceBridgeFromObjectiveCU__FTPSs9AnyObject_MQ__Q_", referenced from: __TFC12MyProject7RestApi12resetRestKitfS0_FT_T_ in RestApi.o __TFC12MyProject16BluetoothManager17_startAdvertisingfS0_FT_T_ in BluetoothManager.o __TFC12MyProject19LoginViewController32registerForKeyboardNotificationsfS0_FT_T_ in LoginViewController.o __TFC12MyProject19LoginViewController35deregisterFromKeyboardNotificationsfS0_FT_T_ in LoginViewController.o __TFC12MyProject19LoginViewController16callProcessLoginfS0_FT_T_ in LoginViewController.o __TFC12MyProject21CheckinViewController16enableBeaconModefS0_FT_T_ in CheckinViewController.o __TFC12MyProject21BarcodeViewController13startScanningfS0_FT_Sb in BarcodeViewController.o ... ld: symbol(s) not found for architecture arm64 clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

This seems to be caused (for most) by linking a third-party library that does not support the requested architecture.

Answer 2

I am a filly when it comes to iOS Objective C, though I have been coding in several other languages for many years. So I am stabbing around in the dark most of the time with Objective C.

I started having this error, "Undefined symbols for architecture armv7", directly after declaring some "global" variables in my .h file like so:

extern NSString *globalNotes;
extern NSString *globalUserCountry;

I was then referring to these variables from the .m file like so:

globalNotes= @"Error (Marker 1010)";
globalUserCountry= @"No result";

THE FIX - To correct this, I changed them to object properties like so:

@property(nonatomic, strong, readwrite) NSString *globalNotes;
@property(nonatomic, strong, readwrite) NSString *globalUserCountry;

And referred to them like so:

self.globalNotes= @"Error (Marker 1010)";
self.globalUserCountry= @"No result";

That seemed to fix my problem.

Answer 3

There appears to be a bug in Xcode 6.0.1 that is causing the linker to drop dependencies in existing project files. I have had this same problem across several different projects, new and old, since the 6.0.1 update.

The easy 'fix' is to just trash your entire 'Derrived Data' and all build files (i.e. manually clean the project) and then rebuild after a fresh Xcode restart. Magically, the linker now finds all the missing architectures/symbols.

NOTE: I have had several incompatible v-table crashes caused by this same bug. The C++ linker appears to be generating incomplete linkages, causing absurd errors where there are no real errors to be found. Again, just rebuild from a clean state and .. ta da.. save yourself a LOT of headache and wasted time tracking down a non-issue.

Answer 4

I have Updated on Yosemite, Xcode 6.1. I have updated gem xcodeproj (0.19.4) and cocoapods (0.34.4).

I have resolve my conflict by :

Clearing the Library/Developer/Xcode/DerivedData folder

replace in Target -> Build Settings -> Linking -> Other Linker Flags : $(OTHER_LDFLAGS)

Check in Target -> Build Phases -> Copy Pods Resources : "${SRCROOT}/Pods/Target Support Files/Pods/Pods-resources.sh"

Answer 5

1) I face the same problem but just clear the applications from derived data from User/Library/Developer/Xcode/DerivedData and I am able to run the code.

2) In your case may be, it will run by removing armv7 architecture from build settings. And make sure your compiler is Default Compiler in Build Settings.

Thanks I hope this helpful to you and everyone.

Answer 6

I solved this issue after trying all that was suggested here with no luck. Like someone said earlier, it's a SourceControl issue.

One of my project files (the one referenced in the error message) was missing from the project browser. However, XCode still had a reference to it (I was going to the class definition when I was selecting "jump to definition" from Xcode GUI).

As a matter of fact, the project.pbxproj was not listing it. This was probably a Git Issue. In any event, I just recreated the file in the same directory it has been recreated and voila.