FAILED: ninja: ‘/hello.cpp‘, needed by ‘out/target/...... missing and no known rule to make it

cpp‘, needed by ‘out/target/...... missing and no known rule to make it"/>

FAILED: ninja: ‘/hello.cpp‘, needed by ‘out/target/...... missing and no known rule to make it

报错完整信息为：FAILED: ninja: '/hello.cpp', needed by 'out/target/product/trinket/obj/EXECUTABLES/hello_intermediates/hello.o', missing and no known rule to make it
10:54:04 ninja failed with: exit status 1

问题原因：由于刚接触安卓编译，Android.mk文件里的相关代码是从网络上复制的，会在每一行后添加空格，将空格删去即可。