CMAKE編譯鏈配置

關於CMAKE交叉編譯時的工具鏈配置，引用官方的說明：官方傳送門

看官方的解釋需要自定義cmake文件，並且在執行cmake時傳入參數-DCMAKE_TOOLCHAIN_FILE=path/to/file來指定cmake文件路徑，CMAKE在解析自定義的CMakelists.txt前已經配置好了編譯器，無法在自定義的CMakelists.txt中重新指定編譯鏈。

自定義的編譯器配置文件官方示例：

set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR arm)

set(CMAKE_SYSROOT /home/devel/rasp-pi-rootfs)
set(CMAKE_STAGING_PREFIX /home/devel/stage)

set(tools /home/devel/gcc-4.7-linaro-rpi-gnueabihf)
set(CMAKE_C_COMPILER ${tools}/bin/arm-linux-gnueabihf-gcc)
set(CMAKE_CXX_COMPILER ${tools}/bin/arm-linux-gnueabihf-g++)

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)