An Xcode beginner's question:
It is my first experience with Xcode 4.6.3.
I am trying to write a very simple console program, that searches for paired BT devices and prints them to an NSLog.
It builds with the following error:
Undefined symbols for architecture x86_64:
"_OBJC_CLASS_$_IOBluetoothDevice", referenced from:
objc-class-ref in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
I searched like crazy. The common problem should be a reference to a file, of which only the header files are imported and no implementation (*.m-file) is found by the linker. The IOBluetooth library is however, a standard Framework like the Foundation Framework.
What am I missing in my above statement?
I also have tried building it for a 32-bit machine (build fails again). It is clearly a linker error, however I have no idea, to what it relates, except that there is an issue with finding the implementation for IOBluetoothDevice, on both x86 and x64 architecture, while the header files are from a standard included Framework, called IOBluetooth?
For your information my main code "main.m" being:
#import <Foundation/Foundation.h>
#import <IOBluetooth/objc/IOBluetoothDevice.h> // Note the import for bluetooth
#import <IOBluetooth/objc/IOBluetoothDeviceInquiry.h> // Note the import for bluetooth
int main(int argc, const char * argv[])
{
#autoreleasepool {
IOBluetoothDevice *currentDevice;
NSArray *devices = [ IOBluetoothDevice pairedDevices];
for (id currentDevice in devices){
NSLog(#"%i : %#",[ currentDevice classOfDevice ], [ currentDevice name ]);
}
}
return 0;
}
Thanks for any help or pointers to the right direction.
It looks like you are missing including the IOBluetooth.framework in your project. You can add it by:
Clicking on your project in the upper left of the left pane (the blue icon).
In the middle pane, click on the Build Phases tab.
Under "Link Binary With Libraries", click on the plus button.
Find the IOBluetooth.framework from the list and hit Add.
This will make sure that the IOBluetooth.framework definitions are found by the linker. You can see that the framework is a member of your target by clicking on the framework in the left pane and seeing the framework's target membership in the right pane (note I've moved the framework under the Frameworks group for organization purposes):
UPD
Apple requires to use arm64 architecture. Do not use x32 libraries in your project
So the answer below is not correct anymore!
Old answer
The new Xcode 5.1 sets the architecture armv7,armv7s,and arm64 as default.
And sometimes the error "build failure “Undefined symbols for architecture x86_64”" may be caused by this. Because, some libs (not Apple's) were compiled for x32 originally and doesn't support x64.
So what you need, is to change the "Architectures" for your project target like this
NB. If you're using Cocoapods - you should do the same for "Pods" target.
Undefined symbols for architecture x86_64: "_OBJC_CLASS_$_xxx",
referenced from:
objc-class-ref in yyy.o
This generally means, you are calling "xxx" (it may be a framework or class) from the class "yyy". The compiler can not locate the "xxx" so this error occurs.
You need to add the missing files(in this case "xxx") by right click on your project folder in navigator window and tap on "Add files to "YourProjectName"" option.
A popup window will open your project files in Finder. There, you can see the missing files and just add them to your project. Don't forget to check the "Copy items if needed" box. Good luck!!
I have also seen this error on Xcode 7.2 when the derived data becomes corrupted (in my case I interrupted a build and suspect that was the root cause).
So if the other solutions (notably Chris's and BraveS's which I suspect are more likely) do not fit your problem try deleting derived data (Select: Window / Projects / Derived Data -> Delete) and re-building.
(Added for reference by others - I know the original question has been answered correctly).
Under Xcode 9.0b5 you may encounter this because Xcode 9.0b5 has a bug in it where when you add source code, it does not honor the target settings. You must go in and set each file's target manually afterwords:
In my Case , it was not a library, it was some classes ..
Undefined symbols for architecture x86_64:
"_OBJC_CLASS_$_ClassNmae", referenced from: objc-class-ref in
SomeClassName" . . .
d: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see
invocation)
Solution
I had several targets in Xcode with several schemas ( Production , Dev etc ) .. some of my newly added implementation ( Class.m ) were missing in
Xcode->Targets->Build Phases->Compile Sources
So I had to add them manually.
then I could compile & build successfully.
I also encountered the same problem , the above methods will not work . I accidentally deleted the files in the following directory on it .
Or
~/Library/Developer/Xcode/DerivedData/
I tried just about everything here but my problem turned out to be the remnants of a previous cocoapods build. What worked for me was:
rm -Rf Pods; pod install
Delete Derived Data (Window/Projects... select your target. click Delete Button)
Rebuild
I have faced this issue many times. This usually comes when you delete your build folder.
The easy solution is to de-integrate and install the pod files again.
pod deintegrate
pod install
When updating to Xcode 7.1, you might see this type of error, and it can't be resolved by any of the above answers. One of the symptoms in my case was that the app runs on the device not in the simulator. You'll probably see a huge number of errors related to pretty much all of the frameworks you're using.
The fix is actually quite simple. You just need to delete an entry from the "Framework Search Paths" setting, found in your TARGETS > Build Settings > Search Paths section (make sure the "All" tab is selected)
If you see another entry here (besides $(inherited)) for your main target(s) or your test target, just delete the faulty path from all targets and rebuild.
I have found this can also occur if you drag a folder with Objective-C files into your project. If that folder appears blue I think it indicates its not properly linked. You can verify this (if you use version control) because whenever you add new files the pbxproj file should update with links to those new files. However you may find that after you added a folder that the pbxproj file did not change (and hence there is a linking error). So you will get auto-complete working and it will find the classes you imported, but when it goes to actually build the image it fails with this error code.
The solution is to not add the folder but rather add the files. Do this and you should see the pbxproj file update and it should fix this error.
This also assumes you've done what was suggested above and have properly linked all the right frameworks.
I know it's an old question but today got the same error and non of the above solutions worked.
Have fixed it however by setting option:
Project -> Architecture -> Build Active Architecture Only
to Yes
and project compiles and builds properly
I had the same error, because instead of deleting a file I simply removed references to it. Locating the file in Finder and removing it helped.
In my case, I built a custom framework with Deployment target set to 9.1, but the Deployment target of my app was lower, which supports 8.1. Minimize the custom framework Deployment target solved my problem.
If you're getting this error when trying to link to a C file, first double check the function names for typos. Next double check that you are not trying to call a C function from a C++ / Objective-C++ environment without using the extern C {} construct. I was tearing my hair out because I had a class that was in a .mm file which was trying to call C functions. It doesn't work because in C++, the symbols are mangled. You can actually see the concrete symbols generated using the nm tool. Terminal to the path of the .o files, and run nm -g on the file that is calling the symbol and the one that should have the symbol, and you should see if they match up or not, which can provide clues for the error.
nm -g file.o
You can inspect the C++ symbols demangled with this:
nm -gC file.o
I got it solved by adding "-lc++" in Other Linker Flags in Build Settings.
In my case problem was compiled framework architecture.
I'm running Xcode 11 and using Swift 5.1
I had 3 target like:
MyApp
MyAppTests
MyAppFrameWork
I was tried to run tests but MyAppFrameWork product was compiled for Generic iOS Devices and the Test target needed an arm x86-64, So I rebuilt Framework for iOS Simulators and test cases successfuly start running.
This is also happend with apple M1 chip.
Here is my solution just check Open using Rosetta
Steps:
Go to application > right click xcode > get info > check Open using Rosetta
Restart the system.
I am late to the party but thought of sharing one more scenario where this could happen.
I was working on a framework and was distributing it over cocoapods.
The framework had both objective c and swift classes and protocols and it was building successfully.
While using pod in another framework or project it was giving this error as I forgot to include .m files in podspec.
Please include .swtift,.h and .m files in your podspec sources as below:
s.source_files = "Projectname/Projectname/**/*.{swift,h,m}"
I hope it saves someone else's time.
in my case I had to add
target 'SomeTargetTests' do
inherit! :search_paths
end
to my podfile and then delete the /Pods directory and run `pod install`
(Xcode 10.1)
This might help somebody. It took me days to finally figure it out. I am working in OBJ-C and I went to:
Project -> Build Phases -> Compile sources and added the new VC.m file I had just added.
I am working with legacy code and I am usually a swifty, new to OBJ-C so I didn't even think to import my .m files into a sources library.
EDIT:
Ran into this problem a second time and it was something else. This answer saved me after 5 hours of debugging. Tried all of the options on this thread and more. https://stackoverflow.com/a/13625967/7842175 Please give him credit if this helps you, but basically you might need to set your file to its target in file inspector.
All in all, this is a very vague Error code that could be caused for a lot of reasons, so keep on trying different options.
What helped me was adding s.static_framework = true to my /podspec in the project that was throwing the error.
For me, this started to happen after merge conflict.
I tried to clean and remove build folder, but none of it helped. This issue kept happening regardless. Then I relinked the reference by deleting the groups that was problematic and re-added to the project and it worked.
Could also be an #include <windows.h> in the .c file that you're trying to compile.
Sometime, I forget to copy library from Release-universal and mistakenly copy from Release-iphoneos. Usually Release-iphoneos contains .a file which has been pruned for X86. and so it gives the error.
in my case, removing selection of target membership and then select again fix the issue.
Check William Cerniuk answer with the attachment photo.
Undefined symbols for architecture x86_64
I have run on this issue when used CocoaPods with some dependency which did not have specific version, that is why after pod update it downloaded the latest version which included some breaking changes
Upgrade dependencies and code for using them
Set specific version of pod
Remove Derived Data[About] folder
In my case I was getting this error: Undefined symbols for architecture x86_64: "_OBJC_CLASS _ $ _ RCTImageLoader"
And I was able to fix it by adding the following line in my Podfile file:
pod 'React-RCTImage', :path => '../node_modules/react-native/Libraries/Image'
Reference
It happens when you are using architecture arm6, arm7 in your current project but any 3rd party framework which you are trying to consume in your project is built over x86_64.
For e.g If you are using Cocoa Pods in your project, then you need to add following script to make sure all 3rd party frameworks ensure arm6, arm7. i.e
Sample podfile with script to be add at end
target 'XYZ_ProjectTarget' do
# Comment the next line if you don't want to use dynamic frameworks
use_frameworks!
# Pods for XYZ_ProjectTarget
pod 'pod_name'
target 'XYZ_TargetTests' do
inherit! :search_paths
# Pods for testing
end
target 'XYZ_TargetUITests' do
# Pods for testing
end
end
post_install do |installer_representation|
installer_representation.project.targets.each do |target|
target.build_configurations.each do |config|
config.build_settings['ARCHS'] = 'armv7 armv7s'
end
end
end
Working on my iPhone app and trying to build for debug and I get "106 duplicate symbols for architecture armv7"?
I am using the .workspace file because I am trying to use CocoaPods. If I don't use the .workspace and instead use the .xcodeproj I don't get the error, but then I get missing -lPods .
In my project I have the following targets in the Project Navigator.
Pods (blue icon)
MyProject (blue icon)
Restkit.xcodeproj (blue icon)
... all my files
The issue is that Restkit is making reference to "AFHTTPClient.h" and all the other AF code, but I included it via CocoaPods. I tried deleting the AFNetworking folder from the RestKit library, but apparently the Restkit library can't find the Pods version of AFNetworking?
Is there a way to get RestKit to use the Pods version? If not how do I go about removing Pods from my project?
There is a line in one of your .h files where your wrote
#include "___.m"
instead of
#include "___.h"
So I fixed it. After removing the RestKit version of AFNetworking, from the vendor folder, I added it back by dragging into Xcode. It asks which project I want it used/copied to and this time I selected RestKitTest (or whatever the RestKitTesting is named). It works now. Maybe I selected both RestKit and RestKitTest before, which was wrong?
I also came up with same error. Generally this kind of error occurs due to duplicate classes and xibs in project folder. For Example in my project I had these classes twice ServiceRequest.h/.m. Get rid of duplicate ones and you are good to go.
In Build Phases -> Compile Sources, make sure you don't have the same file added twice.
"Duplicate symbols for architecture" issue occurs in two situations:
You added a .m file twice into your project
You're using a static library (.a file) which already includes some classes that you include into the project.
For fixing any of those cases, check the linker error and look for the .o files that are duplicated (sample: Reachability.o).
Then go to the build phases -> compile sources and search the specified files, if any one appears twice delete one of them, if only appears once it means that the file is also included in one of the static libraries added to your project. Delete it from your list of sources to be compiled and try again.
I saw this error when, I did drag and drop my calabash framework onto xcode and selected add to targets option in the window thats shown. Basically there were two references to files added
I had to remove the calabash framework manually
Right way of doing it
copy to calabash framework to project directory
then go to xcode project
Choose target -> Build phases -> Link Binary With Libraries and add the frame work using + button
I have noticed that duplicate symbols are caused for Google analytics after installing cocoaPods as well. Once I removed one of archives, either libGoogleAnalytics_debug.a or libGoogleAnalytics.a duplication has gone. But obviously if I removed debug one I will not be able to run os simulator and vica versa. I know its not the solution, but at least it could give an idea what could be a solution. Will come back to this thread if I will figure out how to have both a files in this case.
Edit:
I was able to solve the issue by upgrading from G analytics version 2 to 3. It has only one library file and I guess this is the reason why we don't get duplicated symbols anymore. I hope it makes sense.
When archiving, such en error occurs:
Projects/Dossier/MultiDocument/Helpers/GAD/libGoogleAdMobAds.a(GADGestureCFiles.o)
duplicate symbol _tohex in:
/Users/shmidt/Documents/App Development/Xcode Projects/Dossier/MultiDocument/Helpers/GAD/libGoogleAdMobAds.a(rc4.o)
/Users/shmidt/Documents/App Development/Xcode Projects/Dossier/MultiDocument/Helpers/GAD/libGoogleAdMobAds.a(GADGestureCFiles.o)
ld: 64 duplicate symbols for architecture armv7s
If you're using the Admob v6.2 library make sure you're NOT using the -all_load linker flag, use the -ObjC linker flag instead.
If you can't find any "-all_load" params but also show this error.
you must goto the "project.xcodeproj" and replace "-all_load" with "-ObjC" in "project.pbxproj"
I faced this problem within a Unity game and I had added IronSource Mediation Adapters, if it's your case here's the solution I found:
You should use the pods. I guess you are aware of it, but in case you don't know it, it's something like google play services in the Apple products, designed for taking care of the external packages and libraries to include in the project.
When you manually add the frameworks into the project it conflicts with other codes of the same package that might already be in the project. In my case solution was removing the "GoogleUtilities" and "nanopb" from Google's Admob frameworks and also the "FBCoreKit" from the Facebook ads frameworks(which had conflicts) and added the following code to a dependencies file in the Unity:
<iosPods>
`enter code here`<iosPod name="FBAudienceNetwork" version="5.6.0" />
`enter code here`<iosPod name="Google-Mobile-Ads-SDK" version="7.50.0" />
</iosPods>
This code lets pods take care of the conflicting libraries and removes the duplicate symbols that didn't permit the build to succeed.
I am using SBJson classes in my library and having tried to use the library in my project I am having a duplicate symbol error because I am also using these files in the main project.
I can't add prefixes to these files so how does one usually work around this problem ?
I saw other answers that suggest renaming classes with prefixes, yet this isn't really the solution since it's correct that these files have duplicates - it's an open source code.
You could remove the SBJSON (.m) files from the library project target (using the "Build Phases" screen in Xcode) and then project should be able to compile using the SBJSON files that are part of the main project. There might be issues though, if both projects use different versions of the SBJSON library.
Personally I wish all library projects didn't include other libraries but note (in a "Read Me" file or whatever) that it's a dependency and it's up to the developer to include the dependencies in the main project. I've had a lot of issues with duplicate symbols in the past due to this stuff.
Just Go to Build Setting and
search for No Common Blocks and
set it NO.
And build again you will not get this error again.
CheersKP
You can just include the .h files in your project and remove .m for SBJson. That way you can import the .h in you code and it will compile.