Qt5.1/Qt5.2 + Mac OS 10.9 (Mavericks) + XCode 5.0.2, Undefined symbols for architecture x86_64

Question

Environment : Mac OS 10.9 + Qt5.1/Qt5.2 + OpenCV2.4.7 + XCode(5.0.2)

I can compile the following program via terminal

g++ -L/usr/local/lib -lopencv_         


        

Answer 1

The problem is not with the system. On Mac you just have to include imgcodecs header and include the respective lib files also. This will solve all the trouble you had.

-lopencv_imgcodecs

Answer 2

This issue is answered in this post

http://qt-project.org/forums/viewthread/35646/

and explained by sandy.martel

I quoted here

Qt binary distribution compile with -stdlib=libstdc++ to be compatible with 10.6, Xcode 5 on 10.9 will select -stdlib=libc++ by default (for OS X 10.7 and better only). So symbol using classes from the standard library (like std::string in this case) will not resolve correctly at link time. This is why you’re seeing this error (Undefined symbols for architecture x86_64) . Look with which standard library opencv is built: otool -L libopencv_XXX.dylib. You’ll have to rebuild it with the right one or change Qt’s mkspec to use the newer one.

I solve this by changing ../Qt5.2.0/5.2.0-rc1/clang_64/mkspecs/macx-clang/qmake.conf

from

QMAKE_MACOSX_DEPLOYMENT_TARGET = 10.6

to

QMAKE_MACOSX_DEPLOYMENT_TARGET = 10.9

And remember clean your project before rebuild.

Answer 3

In case you came here, because you changed config+=11 and nothing happend, try to clean your project before rebuild.