title: Cannot build OpenCV framework for iOS
body: <p>I am having trouble building the framework.</p>
  
  <p>I have cloned a copy of OpenCV from here: <a href="https://github.com/Itseez/opencv">https://github.com/Itseez/opencv</a></p>
  
  <p>Then checked that I have the latest cmake 2.8.10.2</p>
  
  <p>Then run build_framework.py in the iOS folder.</p>
  
  <p>e.g.</p>
  
  <pre><code>./opencv/ios/build_framework.py opencv-ios-build
  </code></pre>
  
  <p>Output from this is:</p>
  
  <pre><code>-- Setting up iPhoneOS toolchain
  -- iPhoneOS toolchain loaded
  -- Setting up iPhoneOS toolchain
  -- iPhoneOS toolchain loaded
  -- The CXX compiler identification is Clang 4.2.0
  -- The C compiler identification is Clang 4.2.0
  -- Detecting CXX compiler ABI info
  -- Detecting CXX compiler ABI info - failed
  -- Detecting C compiler ABI info
  -- Detecting C compiler ABI info - failed
  -- Performing Test HAVE_CXX_W
  -- Performing Test HAVE_CXX_W - Failed
  -- Performing Test HAVE_C_W
  -- Performing Test HAVE_C_W - Failed
  -- Performing Test HAVE_CXX_WALL
  -- Performing Test HAVE_CXX_WALL - Failed
  -- Performing Test HAVE_C_WALL
  -- Performing Test HAVE_C_WALL - Failed
  -- Performing Test HAVE_CXX_WERROR_RETURN_TYPE
  -- Performing Test HAVE_CXX_WERROR_RETURN_TYPE - Failed
  -- Performing Test HAVE_C_WERROR_RETURN_TYPE
  -- Performing Test HAVE_C_WERROR_RETURN_TYPE - Failed
  -- Performing Test HAVE_CXX_WERROR_NON_VIRTUAL_DTOR
  -- Performing Test HAVE_CXX_WERROR_NON_VIRTUAL_DTOR - Failed
  ...
  
  -- Could NOT find PythonInterp (missing:  PYTHON_EXECUTABLE) (Required is at least version "2.0")
  -- Performing Test HAVE_CXX_WNO_UNDEF
  -- Performing Test HAVE_CXX_WNO_UNDEF - Failed
  -- Performing Test HAVE_CXX_WNO_SIGN_PROMO
  -- Performing Test HAVE_CXX_WNO_SIGN_PROMO - Failed
  -- Performing Test HAVE_CXX_WNO_MISSING_DECLARATIONS
  -- Performing Test HAVE_CXX_WNO_MISSING_DECLARATIONS - Failed
  -- Performing Test HAVE_CXX_WNO_MISSING_PROTOTYPES
  -- Performing Test HAVE_CXX_WNO_MISSING_PROTOTYPES - Failed
  -- Performing Test HAVE_OBJCXX_FOBJC_EXCEPTIONS
  -- Performing Test HAVE_OBJCXX_FOBJC_EXCEPTIONS - Failed
  -- Performing Test HAVE_CXX_WNO_DEPRECATED_DECLARATIONS
  -- Performing Test HAVE_CXX_WNO_DEPRECATED_DECLARATIONS - Failed
  -- 
  -- General configuration for OpenCV 2.4.9 =====================================
  --   Version control:               unknown
  -- 
  --   Platform:
  --     Host:                        Darwin 12.3.0 i386
  --     Target:                      iOS
  --     CMake:                       2.8.10.2
  --     CMake generator:             Xcode
  --     CMake build tool:            /Applications/CMake 2.8-10.app/Contents/bin/cmakexbuild
  --     Xcode:                       4.6.1
  -- 
  --   C/C++:
  --     Built as dynamic libs?:      NO
  --     C++ Compiler:                /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++  (ver 4.2.0)
  --     C++ flags (Release):         -stdlib=libc++ -headerpad_max_install_names -fvisibility=hidden -fvisibility-inlines-hidden -fPIC   -DNDEBUG -O3 -fomit-frame-pointer -ffast-math  -DNDEBUG
  --     C++ flags (Debug):           -stdlib=libc++ -headerpad_max_install_names -fvisibility=hidden -fvisibility-inlines-hidden -fPIC   -g  -O0 -DDEBUG -D_DEBUG -ggdb3
  --     C Compiler:                  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
  --     C flags (Release):           -fPIC   -O3 -DNDEBUG  -DNDEBUG
  --     C flags (Debug):             -fPIC   -g  -O0 -DDEBUG -D_DEBUG -ggdb3
  --     Linker flags (Release):      
  --     Linker flags (Debug):        
  --     Precompiled headers:         NO
  -- 
  --   OpenCV modules:
  --     To be built:                 core imgproc flann highgui features2d calib3d ml video objdetect contrib legacy nonfree photo softcascade stitching videostab world
  --     Disabled:                    -
  --     Disabled by dependency:      -
  --     Unavailable:                 androidcamera gpu java ocl python superres ts
  -- 
  --   GUI: 
  --     Cocoa:                       YES
  --     OpenGL support:              NO
  -- 
  --   Media I/O: 
  --     ZLib:                        build (ver 1.2.7)
  --     JPEG:                        build (ver 90)
  --     WEBP:                        NO
  --     PNG:                         build (ver 1.5.12)
  --     TIFF:                        NO
  --     JPEG 2000:                   NO
  --     OpenEXR:                     NO
  -- 
  --   Video I/O:
  --     AVFoundation:                YES
  --     QuickTime:                   NO
  --     QTKit:                       YES
  --     V4L/V4L2:                    NO/NO
  -- 
  --   Other third-party libraries:
  --     Use IPP:                     NO
  --     Use Eigen:                   NO
  --     Use TBB:                     NO
  --     Use OpenMP:                  NO
  --     Use GCD                      YES
  --     Use Concurrency              NO
  --     Use C=:                      NO
  --     Use Cuda:                    NO
  --     Use OpenCL:                  NO
  -- 
  --   Python:
  --     Interpreter:                 NO
  -- 
  --   Java:
  --     ant:                         NO
  --     JNI:                         NO
  --     Java tests:                  NO
  -- 
  --   Documentation:
  --     Build Documentation:         NO
  --     Sphinx:                      NO
  --     PdfLaTeX compiler:           NO
  -- 
  --   Tests and samples:
  --     Tests:                       NO
  --     Performance tests:           NO
  --     C/C++ Examples:              NO
  -- 
  --   Install path:                  /Users/Ants/Dev/iOS/opencv-ios-build/build/iPhoneOS-armv7/install
  -- 
  --   cvconfig.h is in:              /Users/Ants/Dev/iOS/opencv-ios-build/build/iPhoneOS-armv7
  -- -----------------------------------------------------------------
  -- 
  -- Configuring done
  -- Generating done
  -- Build files have been written to: /Users/Ants/Dev/iOS/opencv-ios-build/build/iPhoneOS-armv7
  </code></pre>
  
  <p>But it does build Xcode projects.</p>
  
  <p>The process continues to run the compiles but this fails on rand.cpp in the opencv core</p>
  
  <pre><code>    /Users/Ants/Dev/iOS/opencv/modules/core/src/rand.cpp:758:8: error: unknown type name 'pthread_key_t'; did you mean 'pthread_attr_t'?
  static pthread_key_t tlsRNGKey = 0;
         ^~~~~~~~~~~~~
         pthread_attr_t
  /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include/sys/signal.h:157:34: note: 'pthread_attr_t' declared here
  typedef __darwin_pthread_attr_t         pthread_attr_t;
                                          ^
  /Users/Ants/Dev/iOS/opencv/modules/core/src/rand.cpp:758:22: error: no viable conversion from 'int' to 'pthread_attr_t' (aka '_opaque_pthread_attr_t')
  static pthread_key_t tlsRNGKey = 0;
                       ^           ~
  /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include/sys/_types.h:64:8: note: candidate constructor (the implicit copy constructor) not viable: no known conversion from 'int' to 'const _opaque_pthread_attr_t &amp;' for 1st argument
  struct _opaque_pthread_attr_t { long __sig; char __opaque[__PTHREAD_ATTR_SIZE__]; };
         ^
  /Users/Ants/Dev/iOS/opencv/modules/core/src/rand.cpp:759:8: error: unknown type name 'pthread_once_t'; did you mean 'pthread_attr_t'?
  static pthread_once_t tlsRNGKeyOnce = PTHREAD_ONCE_INIT;
         ^~~~~~~~~~~~~~
         pthread_attr_t
  /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include/sys/signal.h:157:34: note: 'pthread_attr_t' declared here
  typedef __darwin_pthread_attr_t         pthread_attr_t;
                                          ^
  /Users/Ants/Dev/iOS/opencv/modules/core/src/rand.cpp:759:39: error: use of undeclared identifier 'PTHREAD_ONCE_INIT'
  static pthread_once_t tlsRNGKeyOnce = PTHREAD_ONCE_INIT;
                                        ^
  /Users/Ants/Dev/iOS/opencv/modules/core/src/rand.cpp:774:5: error: use of undeclared identifier 'pthread_once'
      pthread_once(&amp;tlsRNGKeyOnce, makeRNGKey);
      ^
  5 errors generated.
  </code></pre>
  
  <p>Any ideas?</p>