I know similar questions has been posted but the solutions I found haven't worked at all for me.
I'm using XCode 4.5 and openCV 2.4.3. I built the library from source, I have the compiler set to LLVM GCC 4.2 and whenever I try to use cvCvtColor(), I get the following error message:
Undefined symbols for architecture x86_64:
"_cvCvtColor referenced from:
_main in main.o
Any insight would be greatly appreciated!
I found the problem and I'm kicking myself. It turns out I didn't import a particular library (libopencv_imgproc to be specific) that cvCvtColor() was on.
In Terminal, "cd" to the directory that contains your OpenCV library (or actually libraries, as I see a few of them are built when I look at this "how to build OpenCV tutorial") and then type in this command:
"nm -arch x86_64 _________.a" (fill in the name of the library where the underscores are)
This dumps out all the symbols of the library. You can egrep or search for "cvCvtColor".
My guess is that you've built OpenCV for 32-bit only (and this will be easy to see if you get absolutely no symbols when specifying "-arch x86_64" in the "nm" command) and that you need to also build your OpenCV libraries for 64-bit (x86_64).
Related
Recently I started working with Boost on Windows for a project. It needs to be cross-platform so I also installed it on Mac. Unfortunately; whenever I add it to the Xcode project it gives me a big slew of linker-errors and conversion-warnings.
Example of one of the linker-errors:
Undefined symbols for architecture x86_64:
"boost::system::system_category()", referenced from:
___cxx_global_var_init2 in main.o
boost::asio::error::get_system_category() in main.o
boost::system::error_code::error_code() in main.o "boost::system::generic_category()", referenced from:
___cxx_global_var_init in main.o
___cxx_global_var_init1 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)
Example of one of the conversion-warnings:
In file included from
/usr/local/Cellar/boost/1.57.0/include/boost/date_time/posix_time/posix_time_types.hpp:16:
/usr/local/Cellar/boost/1.57.0/include/boost/date_time/posix_time/posix_time_duration.hpp:24:21: warning: implicit conversion loses integer precision: 'long' to
'hour_type' (aka 'int') [-Wshorten-64-to-32]
time_duration(h,0,0)
I tried several installation methods and configuration methods but it still won't work.
These are my steps:
Compile Boost or get a compiled version of Boost.
Create an XCode project.
Enter this sample code in the main class.
Add the header and library paths to the Xcode project file.
Build.
Compile options I have tried:
Compiling from source using the official guide.
Compiling from source using a few scripts I found here on Stackoverflow.
Installing the brew package manager and downloading a package with binaries.
Configuration options I have tried:
Setting the header search path to /usr/local/Cellar/boost/1.57.0/include or equivalents and
setting the library search path to /usr/local/Cellar/boost/1.57.0/lib or the equivalents.
Setting just the header search path but not the library path.
Option 1 but recursive (causes more errors).
I would appreciate it a lot if someone could point me in the right direction. I think it's something Xcode related since all of the compiled versions give me the same errors.
I found the answer. After the header- and library paths are added to the projects search paths you need to go to "Build Phases". There you need to add the individual libraries you need to the "link libraries to binary" subsection. You can find the necessary files in the lib folder (in the boost folder).
You can choose for either the library files with .a extension or with the .mt.dylib extension. If you choose the .a extension files the library will be added to the compiled version of your program. If you choose the .mt.dylib files then the libraries will not be added to your compiled program. In this case you are assuming the dynamic library files are already present on the computer running the program.
I've built a 32 bit library that is a requirement to my project. Here's its lipo info:
LP:lib hcabral$ lipo -info Release-iphoneos/librmservices_iphone.a
input file Release-iphoneos/librmservices_iphone.a is not a fat file
Non-fat file: Release-iphoneos/librmservices_iphone.a is architecture: armv7
I link the library in my project, it shows up in "Link Binary with binaries", etc., and yet I get this error:
Undefined symbols for architecture armv7:
"std::_List_node_base::hook(std::_List_node_base*)", referenced from:
xpath::YaccParser::getObjectPointer(uft::Value*&, bool) in librmservices_iphone.a(xpath_yacc.o)
xpath::YaccParser::performLexicalAnalysis(uft::Value*&) in librmservices_iphone.a(xpath_yacc.o)
"std::_Rb_tree_rebalance_for_erase(std::_Rb_tree_node_base*, std::_Rb_tree_node_base&)", referenced from:
xpath::Context::removeDynamicContext(uft::Value const&) in librmservices_iphone.a(xpath_context.o)
"_kCFProxyPasswordKey", referenced from:
DLProxySettingsController::getSystemProxySettings() in librmservices_iphone.a(DLProxySettingsController.o)
"_kCFNetworkProxiesHTTPProxy", referenced from:
(...)
All the projects I limited to armv7 and no solution. Any ideas?
So, I have a project A that is pure Objective-C, but it depends on a Project B that is C/C++ and Objective-C, and happens to be 32-bit code only.
Up until Mavericks and Xcode 5.1.1, I built Project B for all platforms (Release and Debug for iOS and i386) in order to debug, run tests and eventually deploy. Project B has its own set of linker flags and options that make it very special.
In project A, I would link the binaries of Project B (libProjectB.a) and it has always worked.
However, during this last iteration, Project A build process complained about missing symbols for armv7, which confused me, because project B is compiled ONLY in armv7 and i386.
The only way I manage to remove 30+ linking errors, was by linking the following frameworks:
libstdc++.6.0.9.dylib
CoreText.framework
CFNetwork.framework
Foundation.framework
I hope these don't look like random frameworks to you, but I found out by adding one by one, based on the type of linking error. For example, I added the CFNetwork only after opening the C++ code and noticing that the symbols would be part of it.
Anyway, again, I don't know why it happened yet, but it happened by using Yosemite and Xcode 6.1. Hope this can shed a light on someone.
I'm trying to receive information from an 0MQ Socket in C or C++, but therefore I have to include zmq.h. By downloading the 0MQ software from their website and including this file. Xcode gives the following error:
Undefined symbols for architecture x86_64:
"_zmq_init", referenced from:
_main 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)
When installing ZeroMQ using brew I get the same error. Is there anyone who know a workaround?
The problem here is that you aren't linking the ZMQ library correctly.
You need to build the library once you've downloaded it (they include all the make scripts you need). Once you have that, you will need to link them to the compiler. I'm not too familiar with XCode, but using gcc it would look something like this:
-L/path/to/zmq/library -lzmq
ZeroMQ is really beautiful though. I've used it on Linux/Windows. Hope you get it working!
I wish to use Tesseract with OpenCV on a C++ project (not iOS) I'm working, but I'm unable to get Tesseract to work with XCode. I've added the .dylib files for Leptonica and Tesseract and it works fine, but then I get the following error when I run the APIExample program
read_params_file: parameter not found: save_raw_choices
If I do not add the .dylib files and try adding the header files obtained through Homebrew, I get the following error
Undefined symbols for architecture x86_64:
"tesseract::TessBaseAPI::GetUTF8Text()", referenced from:
tesseractTest() in main.o
"tesseract::TessBaseAPI::End()", referenced from:
tesseractTest() in main.o
I'm a little inexperienced with development in Mac OS X.
I encountered same problem and found only this remark on google groups:
http://code.google.com/p/tesseract-ocr/issues/detail?id=990
Basically, just use different tessdata - e.g. download spanish and set it as language. It would pass that step and show some results. Though they were not splendid in my case but at least you will see it working:).
Then I would recommend asking at the project google group for help...
I had the same problem when I didn't include the tesseract c flags and libraries when compiling.
if you add this to your cflags: pkg-config --cflags tesseract
and this to your libs: pkg-config --libs tesseract
then it should compile.
I know it is an old question but I didn't found anythink online and after hours I solved this issue by adding the line (-ltesseract) to the Build Settings -> Other Linker Flags in xCode
It is well known that the current version of Qt doesn't allow to convert the project to xcode4 project http://bugreports.qt-project.org/browse/QTBUG-17247. Anyways, at least in theory, it should be possible to compile something in xcode by linking the proper Qt libraries (either dynamic or static), right?
I have taken one Qt 4.7.4 example: "Hello world" and copy/paste the source code into my main. I included the proper headers /QtSDK/Desktop/Qt/473/gcc/include/**. Then I added the three frameworks QtScript, QtCore, QtGui. The linker still gives me errors:
Undefined symbols for architecture x86_64:
"qInitResources_helloscript()", referenced from:
_main in main.o
ld: symbol(s) not found for architecture x86_64
I also tried to link with all the libraries in /QtSDK/Desktop/Qt/473/gcc/include/ but still no luck. Also tried with other Qt creator examples, but I get all other sorts of linker errors.