I am building ipad application in XCode 4. For that, i added some outside frameworks in my project. The code work fine in simulator but showing 24 Mach-O Linker error.
I searched for this topic and get various different reasons for this error but not getting the right one.
Any suggestion will be of great help.
Most likely the library you are using has not been built for arm. For a library to work in the simulator, it must be compiled for i386 architecture. To work on the device, it must be compiled for armv architecture.
To work for both, you need what is called a "fat" binary that contains versions compiled for each of the above. If you don't have that, you will receive the linker errors.
To find out what architectures the library is compiled for, use the following command:
lipo -info mylibrary
Related
I have upgraded to XCode 8.0 and it is giving me grief. The first issue was to do with code signing. Which I fixed by selecting a provisioning profile for debug and release from the General project settings. Weird not sure why it couldn't just work as it was compiling perfectly with the previous XCode. Previously XCode would say there is not provisional profile and prompt to fix it and would fix it. Seems a step back here. Anyways, went passed that issue.
The issue I have been facing all day is this error when I compile
Undefined symbols for architecture arm64:
"_write_ret", referenced from:
_dwsl in libtestlib.a(testlib.o)
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
I searched for write_ret and it is only a prototype in a header file, this function isn't called anywhere at all!! (Background the static library is part of a bigger project I brought only the files/code I needed to compile the static library for iOS). This was compiling perfectly before for years. I went back to the static libary source code and to humour myself I deleted the write_ret prototype and compiled it and updated the library in the my project and rebuilt. Same error again!. What is going on here?? I confirmed it was definitely using the correct built library.
I then decided I'll just built for armv7 only as this is an enterprise app. I went back to the static library project file and got rid of armv7s and arm64 from "valid architectures". I change "architectures" to armv7. I rebuilt the library and updated the project with the new library.
I also went into the main project and change the valid architectures to build for only armv7.
This time when I built my project I get this error
ld: warning: ignoring file /Users/rrr/Library/Developer/Xcode/DerivedData/P-eaxegvaceikvgqgllfiardmoorbv/Build/Products/Debug-iphoneos/libtestlib.a,
file was built for archive which is not the architecture being linked (armv7):
/Users/rrr/Library/Developer/Xcode/DerivedData/P-eaxegvaceikvgqgllfiardmoorbv/Build/Products/Debug-iphoneos/libtestlib.a
In the terminal I ran lipo libtestlib.a -info I get this:
input file libtestlib.a is not a fat file
Non-fat file: libtestlib.a is architecture: armv7
So it is built for armv7, so what is XCode complaining about really?
I am out of ideas now. Can anyone shed some light here?
I would like to get it to work with all the architectures as it was doing before the XCode upgrade I did on Friday. But worst case atleast compile to work only for armv7. My understanding is that it will still run on anything iPhone 5s and newer anyway.
At first, As you already know, you should support arm64 in order to support 64 bit architecture following Apple's rule.
At second, let's talk about undefined symbol issue, your first question.
I am not sure exactly from your situation description but, one thing to my mind reading the question is that your static library may depend on some dylib(dynamic or shared library) which is deprecated from Xcode 7.The possible scenario is your dylib library was red-marked in the project from Xcode 8 update version because this was replaced with tbd instead of dylib. So, this library is now missing status, and you did remove it in the library list and you forgot it. That's why your _write_ret symbol in libtestlib.a cannot be linked for architecture arm64 anymore.(dylib is missing status.)
if this scenario is true, import tbd instead of dylib.(text-based stub libraries).
let's talk about your second question related to error log.
ld: warning: ignoring file /Users/rrr/Library/Developer/Xcode/DerivedData/P- eaxegvaceikvgqgllfiardmoorbv/Build/Products/Debug-iphoneos/libtestlib.a,
file was built for archive which is not the architecture being linked (armv7):
/Users/rrr/Library/Developer/Xcode/DerivedData/P- eaxegvaceikvgqgllfiardmoorbv/Build/Products/Debug-iphoneos/libtestlib.a
This log can be about Build Active Architecture Only in Xcode build setting.
check 'Build Active Architecture Only' from Yes to No.
It error log could be generated when Build Active Architecture Only is set to YES in your build setting situation.
and, if it does not work, Have you ever clean your DerivedData directory and project?
If you already tried, it could be possible that your static library is actually not in the /Users/rrr/Library/Developer/Xcode/DerivedData/P-eaxegvaceikvgqgllfiardmoorbv/Build/Products/Debug-iphoneos/libtestlib.a.
so, you can move your static library output into this project and try it again.
These are just scenario for your situation as I got your question.
I wish it became a little help.
Thanks.
I'm trying to unzip .zip files on iOS.
I tried ZipArchive but got lots of linking warnings about undefined architectures for arm64.
I suppose I could remove the arm64 architecture from XCode, but Apple must have started including it in iOS Xcode project templates by default for a reason, and I don't know enough about the ins and outs of that so don't particularly want to remove it in case it causes headaches in the future.
So I tried ZZipArchive which builds and runs but was failing to open the file, which when I traced through the code I found the failing function was called ZOPEN64(). Surprise surprise it has 64 in its name, can't be a coincidence.
I don't see the point in trying another iOS unzip library as they all seem to be wrappers around minizip etc. and thus will have the same fundamental issues.
Is anybody using an unzip library with iOS 7 AND the latest XCode beta?
What are the consequences of removing the arm64 architecture out of the project if that's the only way for now to get unzip up and running?
To answer your question, the ramifications of removing arm64 from the architectures is that some classes of application will perform slower on devices with 64-bit capable processors (right now just iPhone 5s) than they would with arm64 builds enabled.
Note: at this point arm64 is required for all applications.
I am trying to integrate PSPDFKit for iOS in my project and I have not been yet able to success. After downloading the Demo version, adding the framework to my project, adding all the required libraries and placing
#import <PSPDFKit/PSPDFKit.h>
on the 'prefix' file, I get an linker error:
ld: section __objc_const (address=0x00613EA8, size=4651232504) would make the output executable exceed available address range for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)
NOTE: My project uses PSTCollectionView and I have successfully compiled PSPDFKit on a test project (created only for that effect).
I would really appreciate any help. Thanks in advance.
Apparently, you have too many included files in your PCH file.
Try removing some of them, and include those files only where you need them, not globally.
As far as I understand it, this is a bug in Apple's compiler/linker chain. Please file a radar at radar.apple.com with your failing project. A workaround is to use the source code as a subproject instead of the precompiled binary.
As soon as I can get my hands on such a project, I can experiment with the settings to see if there's any workaround. Seems to only happen under very specific combinations with other 3rd party code.
As many of you noticed; zxing does not work in latest xcode (4.5/ios 6)
Here is use case:
checkout latest version from trunk (as some fixes were already added)
create single view application in xcode 4.5 with ios 6.0
use README to add dependencies, paths etc (just follow step by step)
add zxingcontroller call to class (renamed to mm)
Compilation fails both for simulator and device
It shows 31 error like this one:
Undefined symbols for architecture i386:
"std::string::c_str() const", referenced from
all 31 errors are similar, difference is in symbols name
May be somebody knows how to solve it with this use case?
p.s. if you have app from previous Xcode, it works. Problem is only if you create new app in Xcode 4.5
The issue you have encountered seems to be C++ standard library related.
Actually, whenever you see linker failures in relationship with standard library objects (e.g. std::string), you should check the project settings on all linked libraries and the app-project itself. They usually need to match!
The original ScanTest (which builds ZXingWidget as a subproject) uses the following settings and those need to match your App build-settings if you use the library as is.
For making sure, I created a brand-new project using Xcode 4.5. That project uses ZXingWidget as a prebuilt library but not as a subproject - I dont like subprojects for stuff that is not my own - though this specialty wont influence the results.
The important setting is C++ Standard Library - make sure that is set towards Compiler Default
Little clarification
Actually, you do not need to use C++ Standard Library, you may as well use LLVM C++ standard library with C++11 support. But you will have to use that exact same library in all projects, sub-projects and libraries that link with your project. So if you insist on using the more recent version of that library (C++11 support), then you will have to build the ZXing library with those settings as well.
Last but not least, make sure your Architectures and Valid Architecture settings are matching over all projects and sub projects (fixing the common armv7s linker issue).
First, make sure your Architectures setting is set towards armv7 armv7s within all projects. Then also edit the project settings of all projects towards Valid Architecture armv7s armv7.
You might also want to switch the "Other Warning Flag" -Werror off. Seems to be necessary in Xcode versions > 4.5 (LLVM compiler > 4.1).
It works for me, have you enabled -lstdc++ in your list of Other Linker Flags in the Build Settings tab of the project target? It sounds like it is not recognizing the c++ symbols needed for zXing to build. If this is the case, the above advice should help.
I'm adding adMob provide by google to my iOS app and I'm stuck on this part of the installation:
Add -all_load under Other Linker Flags in the project build info
If I add that flag, then another third party library breaks giving me the error message:
ld: duplicate symbol _vw_chartype_table_p in /Users/josh/ Projects/app/libs/libvt_universal.a(vw_ctype-3279EF26D0C25F3A.o) and / Users/josh/Projects/app/libs/ libvt_universal.a(vw_ctype-34AB9EC0B46D954C.o) for architecture i386
Is there any way to use the adMob library without using -all_load? For example, I've tried -force_load $(SOURCE_ROOT)/adMob/libGoogleAdMobAds.a
but
ld: file not found: /Users/USERNAME/Desktop/latest/bbbb/APPNAME/adMob/libGoogleAdMobAds.a
The reason Google suggests using -all_load is that they are using categories in their code, and Objective-C libraries with categories are not properly loaded by the llvm linker (well that was the case in 4.3 xcode, not sure about 4.4 with the newer clang).
So, I guess if you are brave you can try to just remove the all_load flag. It should build fine. If the bug is NOT fixed, what will happen is when you run your code, it will crash, since none of the categories the library uses will have been loaded. This might be a good thing to do in any case, as your project should build, and if it does not you can fix those problems first.
What I do suggest you do is use -force_load, which has llvm load the categories in the adMob library (among other things). To use it you MUST have a fully qualified path (ie starts at '/') to the library. Obviously if you use Terminal and run:
ls -l /Users/USERNAME/Desktop/latest/bbbb/APPNAME/adMob/libGoogleAdMobAds.a
its going to fail. So enter the proper path - hard coded - for now to just see if you can get the project to first build, then run. If it does you can later figure out what is the appropriate $(VAR) to use to find it inside your project.