Re: Using GNU Make

[Ralf Wildenhues]

Hello Reuben,

* Reuben Thomas wrote on Sat, Apr 04, 2009 at 09:15:43PM CEST:
> On Sat, 4 Apr 2009, Mike Frysinger wrote:
>
>> what would be cool is if automake processed some GNU makeisms in the .am ->
>> .in step.  personally, i use some things like $(wildcard) and $(patsubst)
>> because i hate having to hand maintain a huge list of files -- i inevitably
>> add more and forget to update the Makefile.am list.

There is a FAQ entry about wildcards in the Automake manual.

>> for projects that need to
>> be portable, i put a hack into autogen.sh which builds the list with a shell
>> script and then sed's it into Makefile.am while for projects that do not need
>> to be portable, i change the automake warning level.

Sounds ok to me.

> Given the portability of GNU Make itself and the number of systems that 
> ship it even if it's not the default make, the day cannot be too far off 
> when it makes sense to promote its use in autotools, in the sense of not 
> merely allowing it but allowing it to be required, in the sort of manner 
> I suggested.

What do you mean by "allow it to be required".  You can require it now
for your package using autotools.  Well, if your package is an official
GNU one, then I'm not so sure.

Letting Automake outright require GNU make has two major drawbacks:

1) It causes BSD make to be a second-class citizen.  There are already a
few (rather minor) things which work better with GNU make than with BSD
make, but I'd like to avoid adding any more of this than necessary, and
we try to fix those issues that can be fixed.  That's because BSD makes
are actively developed and used; and given that they have some features
which GNU make doesn't, and for political reasons, there is little
chance that both sets of systems will unify on one of the make tools.

2) If full GNU make syntax is officially deemed ok by Automake, then to
me, it would be a bug if automake doesn't understand that full syntax.
Alas, that is probably never going to happen, this would be a lot of
work, with somewhat dubious benefit, to reimplement GNU make parsing in
Automake.

Also, of course packages like GNU make itself and anything needed to
build it, should not rely on GNU make.  (This is pretty trivially
enforced, GNU make has a build script that requires the system shell
only IIRC.)

> There are a number of times where I've had to work around 
> the lack of GNU make features which are over 10 years old, which seems  
> increasingly silly. For my present project, GNU Zile, which strives to be 
> buildable on any system that conforms with 1993 POSIX, this is fair 
> enough, but increasingly new projects will quite reasonably be assuming  
> POSIX.1-2001, if nothing else because free documentation is widely 
> available for it, unlike the 1993 version.

But POSIX.1.2001 doesn't specify wildcards for `make', either.

Cheers,
Ralf