Re: Question regarding alias expansion..

[Rick Flower]

On Mon, August 4, 2008 9:55 am, Sam Ravnborg wrote:
> On Mon, Aug 04, 2008 at 09:39:18AM -0700, Rick Flower wrote:
>> Hi all...
>>
>> I'm trying to update a build environment that currently uses a perl
>> script
>> that expands certain keywords into specific command line args to GNU
>> Make.. I'm trying to get rid of this script while keeping the same
>> look-n-feel that people are used to.. So, below is what I'd like to be
>> able to do but can't seem to find a way to make it work w/ Make.. Keep
>> in
>> mind that the sample below is simplified in nature and that we've got a
>> handful of these sort of command aliases..
>>
>> old perl script:
>>  % pmake release target=sun
>> --> expanded to the following Make command
>>  % make debug=off asserts=off target=sun
>>
>> what I'd like to see Make handle:
>>  % make release target=sun
>>
>> Unfortunately, I can't seem to find a way to get Make to convert
>> 'release'
>> into a set of predefined (canned) variables that then control the make
>> operation.. I've tried using 'define' but everything enclosed in the
>> 'define' seems to set my variables when I don't want them set.. I also
>> toyed around with target specific variables too as that seemed close to
>> what I was looking for -- unfortunately, it didn't seem to work for my
>> sample test.. Any ideas on how to go about this?
>
> Untested but you get the idea:
>
> ifneq ($(filter release,$(MAKECMDGOALS)),)
>     MY_VAR := 1
>     MY_OTHER_VAR := 2
> endif

Ok -- this sample above seemed to fit what I was trying to do so I
started playing around with it.. While it appears to work at first, I'm
finding that code that checks if the variable was set using 'ifndef'
afterwards is not working as expected.. Below is a sample sequence :

=======================================
...
foo = foo
bar = bar
ifneq ($(filter release,$(MAKECMDGOALS)),)
  MY_VAR := foo
endif
...
ifndef MY_VAR
  MY_VAR := bar
endif
...

ifeq ($(MY_VAR), $(foo))
  include Makefile-foo.mak
endif

ifeq ($(MY_VAR), $(bar))
  include Makefile-bar.mak
endif
=======================================

What I find is that if I invoke make as "make release", it wants to
include Makefile-bar.mak which seems to imply that the 'ifndef' is not
working... Now, I should note that my Makefiles are in various pieces with
the alias code in one file and the checking code in another file that is
read in later.  I did just check one thing -- if I merge the alias code
into the same file where the 'ifndef' check is done, then everything works
-- why is that?  It seems like If it matters, this is with GNU Make 3.81.