Dear Paul, Many thanks for your response.
I was not trying to debate :) It seems I used "defined" where youu use "set" but that's what I meant. Shouldn't make set this variable to theempty string rather than not setting it at all? Cheers, Sébastien. Paul Smith (2021/02/01 09:17 -0500): > On Mon, 2021-02-01 at 11:49 +0100, Sébastien Hinderer wrote: > > 'Make' will set the special variable 'MAKECMDGOALS' to the list of > > goals you specified on the command line. If no goals were given on > > the command line, this variable is empty. > > > > If I define the following Makefile: > > > > ifeq "$(MAKECMDGOALS)" "" > > > > make --warn-undefined-variables > > > > Makefile:1: warning: undefined variable 'MAKECMDGOALS' > > > > Am I correct that there is a mismatch between make's documented and > > real behaviour? > > Hm. Well, I could use a language lawyer's response and say that "this > variable is empty" is not the same thing as "this variable is set to > the empty value". > > The variable _IS_ empty, in the same way that any unset variable is > empty. > > If you want to tell the difference between a variable that is not set > at all versus set to the empty string, you have to use the > $(origin ...) function. > > Instead of your code you could use: > > MAKECMDGOALS ?= default > > which will set MAKECMDGOALS IFF it has never been set at all (not even > to the empty string). > > Probably this section of the documentation should be updated to be more > clear so that reading it doesn't require language lawyering. >
