Automatically setting jobs (-j) flag for a multicore machine?

Question

I have a Makefile on a machine that has a ton of cores in it, but I always seem to forget to write -jX when compiling my project and it takes way longer than it

Answer 1

On Ubuntu 16.4 using all CPU cores:

export MAKEFLAGS='-j$(nproc)'

or

export MAKEFLAGS='-j 2'