Apple Mach-O Linker (Id) error

Question

Got this error for the first time, I have looked around and cannot find a solution to help me, I have cleaned my build and also checked to make sure I am compiling for the latest firmware.

This happened after I tired implementing a reachability solution I found over here I imported the two reachability files (.m/.h) then added this code into the .m file and delared t in the . h of the reachability files

-(BOOL)reachable {
    Reachability*r =[Reachability reachabilityWithHostName:@"enbr.co.cc"];
    NetworkStatus internetStatus =[r currentReachabilityStatus];
    if(internetStatus ==NotReachable){
        return NO;
    }
    return YES;}

After that I called the function from both of my viwcontrollers viewwillappear methods like so..

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];


    //-- Check Reachability START ---->
    Reachability *reach = [[Reachability alloc] init];

    if ([reach reachable]) {
            NSLog(@"Reachable");
    }
    else {
        NSLog(@"Not Reachable");
    }
     //-- Check Reachability END ---->
}

No errors were produced untill I tried to build and run in the simulator. This is the error I received :(

Ld /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Products/Debug-iphonesimulator/wizcode.app/wizcode normal i386 cd "/Users/imac/Documents/Iphone applications/wizsanCode/wizsanCode.5/wizcode" setenv MACOSX_DEPLOYMENT_TARGET 10.6 setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"

/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/llvm-gcc-4.2 -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk -L/Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Products/Debug-iphonesimulator -F/Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Products/Debug-iphonesimulator -filelist /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Intermediates/wizcode.build/Debug-iphonesimulator/wizcode.build/Objects-normal/i386/wizcode.LinkFileList -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -lz -framework CoreGraphics -framework MobileCoreServices -framework SystemConfiguration -framework CFNetwork -framework UIKit -framework Foundation -o /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Products/Debug-iphonesimulator/wizcode.app/wizcode

ld: duplicate symbol _OBJC_IVAR_$_Reachability.reachabilityRef in /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Intermediates/wizcode.build/Debug-iphonesimulator/wizcode.build/Objects-normal/i386/Reachability-183E2D17A6B26176.o and /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Intermediates/wizcode.build/Debug-iphonesimulator/wizcode.build/Objects-normal/i386/Reachability-183E2D17A6B26176.o for architecture i386 collect2: ld returned 1 exit status Command /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/llvm-gcc-4.2 failed with exit code 1 ld: duplicate symbol _OBJC_IVAR_$_Reachability.reachabilityRef in /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Intermediates/wizcode.build/Debug-iphonesimulator/wizcode.build/Objects-normal/i386/Reachability-183E2D17A6B26176.o and /Users/imac/Library/Developer/Xcode/DerivedData/wizcode-ccyrqptvfsabmbahgxartbvxwurq/Build/Intermediates/wizcode.build/Debug-iphonesimulator/wizcode.build/Objects-normal/i386/Reachability-183E2D17A6B26176.o for architecture i386

Command /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/llvm-gcc-4.2 failed with exit code 1

Answer 1

So, the problem has been resolved.

What happened was when I imported the reachability files over into my build something funny was happening and somehow I deleted the reachability files that were already in my build being used by the "all seeing I" ASIHTTPRequest methods I was using for transporting my data... which messed everything up.

So long story short I replaced the files and everything is working fine and I also found out that ASIHTTPTequest is taking care of the reachability for me :) how cool is that.

Answer 2

Check if SystemConfiguration is linked properly. Anyway, clean up your code:

+ (BOOL)reachable {
    Reachability *r = [Reachability reachabilityWithHostName:@"enbr.co.cc"];
    NetworkStatus internetStatus = [r currentReachabilityStatus];
    return internetStatus != NotReachable;
}

And then just call [Reachability reachable] wherever you need. This also fixes a memory leak you have.

Answer 3

Just to add to this, it happened me after I regenerated managed subclasses and it didn't actually overwrite the existing ones but just made new duplicates. I just deleted both and regenerated and it was all good.