Compiling drivers/staging

make mrproper
make allmodconfig
make -j3 all
make C=1 M=drivers/staging

You need to interrupt make all with a sigint once it starts compiling init

Also, make allmodconfig enables all modules. A lot of drivers are built as modules whereas make allyesconfig will just enable all config options.

Also, I've used make -j3 all because I use a 4 core processor. You can do make -j$(nproc) all

I terminate the process with a SIGINT or a Ctrl+C once I started observing CC flags continuously.

Also, make mrproper instead of make clean because make clean only cleans object files and make mrproper cleans everything.

This worked for me, let me know if I am wrong. :)