Subject: Re: bug#32269: Expanding variables

From: Philip Prindeville <[email-masked]>
Date: Wed, 25 Jul 2018 17:00:25 -0600

> On Jul 25, 2018, at 4:15 PM, Eric Blake <[email-masked]> wrote:
> 
> On 07/25/2018 05:06 PM, Philip Prindeville wrote:
> 
>> Well, the above assumes Gnu Make, yes.
>> How many other flavors of Make does automake/autoconf work with?
> 
> At the moment, all of them.
> 
> Automake 2.0 (currently a work in progress if you check out the right branches in git) requires GNU make, for more compact makefiles at the expense of ditching portability to other arcane makes, now that GNU make is more likely to be easily obtained on modern systems.  But automake 1.x still tries as hard as possible to produce Makefiles portable to all common make implementations, as long as your Makefile.am doesn't add non-portable code to be passed through to Makefile.
> 

In the absence of Gnu make, the other choice would be to emit:

cat <<_EOF_ > /tmp/extvar$$.mk
include $(pwd)/Makefile

xyzzy:
	@echo ‘\$(variable)’
_EOF_

then we could run “variable=$(make -f /tmp/extvar$$.mk xyzzy)” from inside configure… a little uglier than using val.% as a target, but…