title: building opencv 2.4.6 on Mac - Mavericks
body: <p>I downloaded <a href="http://opencv.org/downloads.html" rel="nofollow">opencv 2.4.6</a> for mac OSX (Mavericks). Untared  the tar file and made the following <a href="http://tilomitra.com/opencv-on-mac-osx/" rel="nofollow">steps</a>:</p>
  
  <pre><code>cd opencv-2.4.6.1/
  mkdir build
  cd build/
  cmake -G "Unix Makefiles" ..
  make -j8
  </code></pre>
  
  <p>But I get an error on the build </p>
  
  <pre><code>/Users/bobo/dir/opencv/opencv-2.4.6.1/modules/core/perf/perf_main.cpp:3:1: error: 
        multiple unsequenced modifications to 'argc' [-Werror,-Wunsequenced]
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/imgproc/perf/perf_main.cpp:3:1: error: 
        multiple unsequenced modifications to 'argc' [-Werror,-Wunsequenced]
  CV_PERF_TEST_MAIN(core)
  ^~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:501:5: note: 
        expanded from macro 'CV_PERF_TEST_MAIN'
      CV_PERF_TEST_MAIN_INTERNALS(modulename, plain_only, __VA_ARGS__)\
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:480:12: note: 
        expanded from macro 'CV_PERF_TEST_MAIN_INTERNALS'
      while (++argc &gt;= (--argc,-1)) {__VA_ARGS__; break;} /*this ugly construct...
             ^          ~~
  CV_PERF_TEST_MAIN(imgproc)
  ^~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:501:5: note: 
        expanded from macro 'CV_PERF_TEST_MAIN'
      CV_PERF_TEST_MAIN_INTERNALS(modulename, plain_only, __VA_ARGS__)\
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:480:12: note: 
        expanded from macro 'CV_PERF_TEST_MAIN_INTERNALS'
      while (++argc &gt;= (--argc,-1)) {__VA_ARGS__; break;} /*this ugly construct...
             ^          ~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/highgui/perf/perf_main.cpp:3:1: error: 
        multiple unsequenced modifications to 'argc' [-Werror,-Wunsequenced]
  CV_PERF_TEST_MAIN(highgui)
  ^~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:501:5: note: 
        expanded from macro 'CV_PERF_TEST_MAIN'
      CV_PERF_TEST_MAIN_INTERNALS(modulename, plain_only, __VA_ARGS__)\
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:480:12: note: 
        expanded from macro 'CV_PERF_TEST_MAIN_INTERNALS'
      while (++argc &gt;= (--argc,-1)) {__VA_ARGS__; break;} /*this ugly construct...
             ^          ~~
  1 error generated.
  1 error generated.
  make[2]: *** [modules/core/CMakeFiles/opencv_perf_core.dir/perf/perf_main.cpp.o] Error 1
  make[1]: *** [modules/core/CMakeFiles/opencv_perf_core.dir/all] Error 2
  make[1]: *** Waiting for unfinished jobs....
  make[2]: *** [modules/highgui/CMakeFiles/opencv_perf_highgui.dir/perf/perf_main.cpp.o] Error 1
  make[2]: *** Waiting for unfinished jobs....
  1 error generated.
  make[2]: *** [modules/imgproc/CMakeFiles/opencv_perf_imgproc.dir/perf/perf_main.cpp.o] Error 1
  make[1]: *** [modules/imgproc/CMakeFiles/opencv_perf_imgproc.dir/all] Error 2
  [ 50%] [ 50%] [ 50%] Building CXX object modules/highgui/CMakeFiles/opencv_perf_highgui.dir/perf/perf_precomp.cpp.o
  Building CXX object modules/features2d/CMakeFiles/opencv_perf_features2d.dir/perf/perf_fast.cpp.o
  Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_descriptors_regression.cpp.o
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_detectors_regression.cpp.o
  [ 50%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_ffmpeg.cpp.o
  [ 50%] Building CXX object modules/calib3d/CMakeFiles/opencv_perf_calib3d.dir/perf/perf_main.cpp.o
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_perf_features2d.dir/perf/perf_main.cpp.o
  make[1]: *** [modules/highgui/CMakeFiles/opencv_perf_highgui.dir/all] Error 2
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_fast.cpp.o
  [ 50%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_fourcc.cpp.o
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_perf_features2d.dir/perf/perf_orb.cpp.o
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/calib3d/perf/perf_main.cpp:3:1: error: 
        multiple unsequenced modifications to 'argc' [-Werror,-Wunsequenced]
  CV_PERF_TEST_MAIN(calib3d)
  ^~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:501:5: note: 
        expanded from macro 'CV_PERF_TEST_MAIN'
      CV_PERF_TEST_MAIN_INTERNALS(modulename, plain_only, __VA_ARGS__)\
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:480:12: note: 
        expanded from macro 'CV_PERF_TEST_MAIN_INTERNALS'
      while (++argc &gt;= (--argc,-1)) {__VA_ARGS__; break;} /*this ugly construct...
             ^          ~~
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_keypoints.cpp.o
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/features2d/perf/perf_main.cpp:3:1: error: 
        multiple unsequenced modifications to 'argc' [-Werror,-Wunsequenced]
  CV_PERF_TEST_MAIN(features2d)
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:501:5: note: 
        expanded from macro 'CV_PERF_TEST_MAIN'
      CV_PERF_TEST_MAIN_INTERNALS(modulename, plain_only, __VA_ARGS__)\
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /Users/bobo/dir/opencv/opencv-2.4.6.1/modules/ts/include/opencv2/ts/ts_perf.hpp:480:12: note: 
        expanded from macro 'CV_PERF_TEST_MAIN_INTERNALS'
      while (++argc &gt;= (--argc,-1)) {__VA_ARGS__; break;} /*this ugly construct...
             ^          ~~
  1 error generated.
  make[2]: *** [modules/calib3d/CMakeFiles/opencv_perf_calib3d.dir/perf/perf_main.cpp.o] Error 1
  make[1]: *** [modules/calib3d/CMakeFiles/opencv_perf_calib3d.dir/all] Error 2
  [ 50%] Building CXX object modules/features2d/CMakeFiles/opencv_perf_features2d.dir/perf/perf_precomp.cpp.o
  1 error generated.
  make[2]: *** [modules/features2d/CMakeFiles/opencv_perf_features2d.dir/perf/perf_main.cpp.o] Error 1
  make[2]: *** Waiting for unfinished jobs....
  [ 51%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_framecount.cpp.o
  [ 51%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_main.cpp.o
  [ 51%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_grfmt.cpp.o
  [ 51%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_gui.cpp.o
  [ 51%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_matchers_algorithmic.cpp.o
  [ 51%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_main.cpp.o
  [ 51%] [ 52%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_positioning.cpp.o
  Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_mser.cpp.o
  [ 52%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_precomp.cpp.o
  [ 52%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_video_io.cpp.o
  make[1]: *** [modules/features2d/CMakeFiles/opencv_perf_features2d.dir/all] Error 2
  [ 52%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_nearestneighbors.cpp.o
  [ 52%] Building CXX object modules/highgui/CMakeFiles/opencv_test_highgui.dir/test/test_video_pos.cpp.o
  [ 52%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_orb.cpp.o
  [ 52%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_precomp.cpp.o
  [ 52%] Building CXX object modules/features2d/CMakeFiles/opencv_test_features2d.dir/test/test_rotation_and_scale_invariance.cpp.o
  Linking CXX executable ../../bin/opencv_test_highgui
  [ 52%] Built target opencv_test_highgui
  Linking CXX executable ../../bin/opencv_test_features2d
  [ 52%] Built target opencv_test_features2d
  make: *** [all] Error 2
  </code></pre>