使用官方文档编译uboot 出现如下错误

Built /home/omni/work/uboot/build/board/khadas/kvim/firmware/bl21.bin successfully

    CPP task_entry.s
    CPP user_task.lds

aarch64-linux-gnu-cpp: error: unrecognized command line option ‘-mthumb’
aarch64-linux-gnu-cpp: error: unrecognized command line option ‘-mno-sched-prolog’
Makefile:111: recipe for target ‘/home/omni/work/uboot/build/scp_task/user_task.lds’ failed
make[2]: *** [/home/omni/work/uboot/build/scp_task/user_task.lds] Error 1
/home/omni/work/uboot/Makefile:914: recipe for target ‘/home/omni/work/uboot/build/scp_task/bl301.bin’ failed
make[1]: *** [/home/omni/work/uboot/build/scp_task/bl301.bin] Error 2
Makefile:147: recipe for target ‘sub-make’ failed
make: *** [sub-make] Error 2

开发环境:ubuntu 16.04

编译Android 8.0请参考这个帖子