How to pass macro definition from “make” command line arguments (-D) to C source code?

Question

I usually pass macro definitions from \"make command line\" to a \"makefile\" using the option : -Dname=value. The definition is accessible inside the makefile.

I al

Answer 1

Call make this way

make CFLAGS=-Dvar=42

because you do want to override your Makefile's CFLAGS, and not just the environment (which has a lower priority with regard to Makefile variables).