toolchain.cmake:
set (CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR arm)
set(CROSS_CHAIN_PATH /usr/bin/arm-linux)
set(CMAKE_C_COMPILE "${CROSS_CHAIN_PATH}/bin/arm-linux-gcc")
set(CMAKE_CXX_COMPILE "${CROSS_CHAIN_PATH}/bin/arm-linux-g++")
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cmake .. -DCMAKE_TOOLCHAIN_FILE=/root/toolchain.cmake