Technical Q&A QA1321
How to solve '_objc_exception_set_functions' ZeroLink errors in Xcode


Q: I am getting an undefined symbol error for _objc_exception_set_functions when I try to launch my application in Xcode. How do I fix this?

A: You may get the following errror when you try to run/debug your application in Xcode:



Listing 1. Typical ZeroLink error.


dyld:  

/Users/vincent/development/Cocoa/BuckStat/build/BuckStat.app/Contents/

MacOS/BuckStat Undefined symbols:

Foundation undefined reference to _objc_exception_set_functions

expected to be defined in

/System/Library/PrivateFrameworks/ZeroLink.framework/Versions/A/

Resources/libobjc.A.dylib




This error is caused by having installed the Xcode Developer Preview and then having done an upgrade install to a GM release of Xcode without first uninstalling the preview release. Pre-release software should always be uninstalled (by using the /Developer/Tools/uninstall-devtools.pl script) before installing GM releases of that software. In this case, the error can be easily fixed by removing a file left over from the preview release, like so in the Terminal:



Listing 2. Type this from the command line.


sudo rm

/System/Library/PrivateFrameworks/ZeroLink.framework/Versions/A/

Resources/libobjc.A.dylib





[Oct 29, 2003]


Developer Documentation | Technical Notes | Development Kits | Sample Code