System information (version)

• OpenCV => master
• Operating System / Platform => iOS
• Compiler => XCode 12.2

Detailed description

Trying to build with:
./opencv/platforms/ios/build_framework.py --iphoneos_archs=arm64 --iphonesimulator_archs=x86_64 iostest

Fails at the start of the simulator build with:
Executing: cmake -GXcode -DAPPLE_FRAMEWORK=ON -DCMAKE_INSTALL_PREFIX=install -DCMAKE_BUILD_TYPE=Release -DOPENCV_INCLUDE_INSTALL_PATH=include -DOPENCV_3P_LIB_INSTALL_PATH=lib/3rdparty -DFRAMEWORK_NAME=opencv2 -DIOS_ARCH=x86_64 -DCMAKE_TOOLCHAIN_FILE=/Users/gilespayne/ContribNew/opencv/platforms/ios/cmake/Toolchains/Toolchain-iPhoneSimulator_Xcode.cmake /Users/gilespayne/ContribNew/opencv
-- Setting up iPhoneSimulator toolchain for IOS_ARCH='x86_64'
-- iPhoneSimulator toolchain loaded
-- Setting up iPhoneSimulator toolchain for IOS_ARCH='x86_64'
-- iPhoneSimulator toolchain loaded
-- The CXX compiler identification is AppleClang 12.0.0.12000032
-- The C compiler identification is AppleClang 12.0.0.12000032
CMake Error at CMakeLists.txt:109 (enable_language):
No CMAKE_CXX_COMPILER could be found.
CMake Error at CMakeLists.txt:109 (enable_language):
No CMAKE_C_COMPILER could be found.

If I run the cmake command that failed I get:
cmake -GXcode -DAPPLE_FRAMEWORK=ON -DCMAKE_INSTALL_PREFIX=install -DCMAKE_BUILD_TYPE=Release -DOPENCV_INCLUDE_INSTALL_PATH=include -DOPENCV_3P_LIB_INSTALL_PATH=lib/3rdparty -DFRAMEWORK_NAME=opencv2 -DIOS_ARCH=x86_64 -DCMAKE_TOOLCHAIN_FILE=/Users/gilespayne/ContribNew/opencv/platforms/ios/cmake/Toolchains/Toolchain-iPhoneSimulator_Xcode.cmake /Users/gilespayne/ContribNew/opencv
-- Setting up iPhoneSimulator toolchain for IOS_ARCH='x86_64'
CMake Error at platforms/ios/cmake/Toolchains/common-ios-toolchain.cmake:98 (message):
IPHONEOS_DEPLOYMENT_TARGET is not specified
Call Stack (most recent call first):
platforms/ios/cmake/Toolchains/Toolchain-iPhoneSimulator_Xcode.cmake:3 (include)
/usr/local/Cellar/cmake/3.18.4/share/cmake/Modules/CMakeDetermineSystem.cmake:93 (include)
CMakeLists.txt:109 (enable_language)

Steps to reproduce

Run the above build command

Issue submission checklist

• I report the issue, it's not a question
• I updated to latest OpenCV version and the issue is still there