OpenCV编译iOS Framework问题解决

编译版本

• Opencv 3.4.1
• xCode 10.2.1
• cMake 3.11

错误一

编译报错：
CalledProcessError: Command '['cmake', '-GXcode', '-DAPPLE_FRAMEWORK=ON', '-DCMAKE_INSTALL_PREFIX=install', '-DCMAKE_BUILD_TYPE=Release', '-DIOS_ARCH=armv7', '-DCMAKE_TOOLCHAIN_FILE=/Users/zhangfan/Documents/opencv-3.4.1/platforms/ios/cmake/Toolchains/Toolchain-iPhoneOS_Xcode.cmake', '-DENABLE_NEON=ON', '/Users/zhangfan/Documents/opencv-3.4.1']' returned non-zero exit status 1

日志错误:
error: An empty identity is not valid when signing a binary for the product type 'Application'

通过将cmake从3.11升级到最新开始出现问题二。

错误二

ld: library not found for -lstdc++
clang: error: linker command failed with exit code 1 (use -v to see invocation)

解决：
将/platforms/ios/cmake/Toolchains/common-ios-toolchain.cmake中的6.0全部改为8.0，开始出现错误三

错误三

error "C++11 is not supported"

说实话这个我没解决，真的不知道怎么办，最后我把最新的opencv-4.1.0里的opencv-4.1.0/platforms/ios拷贝到了3.4.1替换了对应文件夹里面文件解决了

错误四

3rdparty/libpng/CMakeLists.txt:7
修改3rdparty/libpng/CMakeLists.txt：7，

# if(ENABLE_NEON)
#   project(${PNG_LIBRARY} C ASM)
# else()
#   project(${PNG_LIBRARY} C)
# endif()

project(${PNG_LIBRARY} C)

然后再编译就没在发生问题，如果还有什么问题，请诸位不吝赐教