Set defaults in a separate file to keep your other file lighter. Such as a some constants which may or may not need to be override by a user.

Iā€™m not sure if the curly brackets are right here. See also the other pages on conditionals and default values.

  • defaults.mk 
      FIZZ = ${FIZZ}
  BUZZ = ${BUZZ}

  export

Then import the defaults.

  • Makefile 
      include defaults.mk

  foo:
      echo $(FIZZ)