title: Getting OpenCV to work on the Iphone
body: <p>I tried to follow <a href="https://github.com/niw/iphone_opencv_test" rel="nofollow">these instructions</a> get OpenCV to compile on my MAC MINI, but failed at step 6: </p>
  
  <p><strong>../opencv_cmake.sh Simulator ../OpenCV-2.1.0</strong></p>
  
  <p>I got these errors, and I can't make sense of it. Any clues? </p>
  
  <pre><code>Starting cmake...
  Target SDK            = iPhoneSimulator
  iOS SDK Version       = 4.1
  iOS Deployment Target = 3.0
  OpenCV Root           = ../OpenCV-2.1.0
  OpenCV Install Prefix = /Users/haoest/Development/iphone_opencv_test/build_simulator/../opencv_simulator
  
  -- The C compiler identification is GNU
  -- The CXX compiler identification is GNU
  -- Checking whether C compiler has -isysroot
  -- Checking whether C compiler has -isysroot - yes
  -- Checking whether C compiler supports OSX deployment target flag
  -- Checking whether C compiler supports OSX deployment target flag - yes
  -- Check for working C compiler: /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc
  -- Check for working C compiler: /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc -- broken
  CMake Error at /Applications/CMake 2.8-4.app/Contents/share/cmake-2.8/Modules/CMakeTestCCompiler.cmake:52 (MESSAGE):
    The C compiler
    "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc" is
    not able to compile a simple test program.
  
    It fails with the following output:
  
     Change Dir: /Users/haoest/Development/iphone_opencv_test/build_simulator/CMakeFiles/CMakeTmp
  
  
  
    Run Build Command:/usr/bin/make "cmTryCompileExec/fast"
  
    /usr/bin/make -f CMakeFiles/cmTryCompileExec.dir/build.make
    CMakeFiles/cmTryCompileExec.dir/build
  
    "/Applications/CMake 2.8-4.app/Contents/bin/cmake" -E cmake_progress_report
    /Users/haoest/Development/iphone_opencv_test/build_simulator/CMakeFiles/CMakeTmp/CMakeFiles
    1
  
    Building C object CMakeFiles/cmTryCompileExec.dir/testCCompiler.c.o
  
    /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc
    -isysroot
    /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.1.sdk
    -mmacosx-version-min="10.6" -o
    CMakeFiles/cmTryCompileExec.dir/testCCompiler.c.o -c
    /Users/haoest/Development/iphone_opencv_test/build_simulator/CMakeFiles/CMakeTmp/testCCompiler.c
  
  
    Linking C executable cmTryCompileExec
  
    "/Applications/CMake 2.8-4.app/Contents/bin/cmake" -E cmake_link_script
    CMakeFiles/cmTryCompileExec.dir/link.txt --verbose=1
  
    /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc
    -isysroot
    /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.1.sdk
    -mmacosx-version-min="10.6" -Wl,-search_paths_first
    -Wl,-headerpad_max_install_names
    CMakeFiles/cmTryCompileExec.dir/testCCompiler.c.o -o cmTryCompileExec
  
    ld: warning: in
    /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.1.sdk/usr/lib/libSystem.dylib,
    file was built for i386 which is not the architecture being linked (x86_64)
  
    Undefined symbols:
  
      "_exit", referenced from:
          start in crt1.10.6.o
  
    ld: symbol(s) not found
  
    collect2: ld returned 1 exit status
  
    make[1]: *** [cmTryCompileExec] Error 1
  
    make: *** [cmTryCompileExec/fast] Error 2
  
  
  
  
  
    CMake will not be able to correctly generate this project.
  Call Stack (most recent call first):
    CMakeLists.txt:39 (project)
  </code></pre>
  
  <p>-- Configuring incomplete, errors occurred!</p>