Detecting C & CXX compiler error - opencv ios

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Hi,

I am trying to compile opencv 2.4.6.0 on a machine with iOS 6.1, Xcode 4.6.3 and Mac OS X 10.7.5. I have been following installation instructions on opencv website to install opencv ios framework. However I am getting few compilation errors while running the script:

`python opencv/platforms/ios/build_framework.py ios`

I have tried to narrow down the cause of the compilation problems by running the cmake commands given in the python script separately on the terminal window. So if I run:

cmake -GXcode -DCMAKE_TOOLCHAIN_FILE=../ios/cmake/Toolchains/Toolchain-iPhoneSimulator_Xcode.cmake -DOPENCV_BUILD_3RDPARTY_LIBS=YES -DCMAKE_XCODE_ATTRIBUTE_GCC_VERSION="com.apple.compilers.llvmgcc42" ../

then system is unable to detect C and CXX compiler info and most of the tests are failed as shown below:

-- Setting up iPhoneSimulator toolchain
-- iPhoneSimulator toolchain loaded
-- Setting up iPhoneSimulator toolchain
-- iPhoneSimulator 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_FSIGNED_CHAR
-- Performing Test HAVE_CXX_FSIGNED_CHAR - Failed
-- Performing Test HAVE_C_FSIGNED_CHAR
-- Performing Test HAVE_C_FSIGNED_CHAR - Failed

However if I run same cmake command without specifying -DCMAKE_TOOLCHAIN_FILE then I dont get CXX and C compiler error as shown below:

cmake -GXcode -DOPENCV_BUILD_3RDPARTY_LIBS=YES -DCMAKE_XCODE_ATTRIBUTE_GCC_VERSION="com.apple.compilers.llvmgcc42" ../

-- The CXX compiler identification is Clang 4.2.0
-- The C compiler identification is Clang 4.2.0
-- Check for working CXX compiler using: Xcode
-- Check for working CXX compiler using: Xcode -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working C compiler using: Xcode
-- Check for working C compiler using: Xcode -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Performing Test HAVE_CXX_FSIGNED_CHAR
-- Performing Test HAVE_CXX_FSIGNED_CHAR - Success
-- Performing Test HAVE_C_FSIGNED_CHAR

I understand that this error is not due to opencv but I was wondering if someone also faced similar problem while installing opencv.

Thanks for your time. Shakir