[postgis-devel] autoconf versions

[Paul Ramsey]

> On Jan 6, 2022, at 12:57 PM, Paul Ramsey <pramsey at cleverelephant.ca> wrote:
> 
> 
>> On Jan 5, 2022, at 2:57 PM, Sandro Santilli <strk at kbt.io> wrote:
>> 
>> On Wed, Jan 05, 2022 at 03:59:34PM -0500, Greg Troxel wrote:
>> 
>>> Looking at autoconf releases, we should support 2.69, released in
>>> 2012-04 and current until 2020-12, and I see zero point in supporting
>>> anything older.  Even the CentOS people will be ok with that, I think.
>> 
>> Autoconf 2.69 works for me (that's why I have in all my dev machines)
>> 
> 
> Hadn't really gotten into this, so the reason I see issues is because after 9 years, GNU released a new autoconf last year (2.70) and then another this year (2.71) and my package manager happily moved on to the new versions.
> 
> So far it looks like 2.69 actually supports the non-obsolete stuff that the warning messages want us to use, up moving up our file won't break people with "old" (two releases but 10 years ago) version 2.69.  The major problem is that we depend on a bunch of macro files we've vendored in that use those obsolete functions, and rewriting those vendored files to use the new ones would be super hard, so I'm currently sleuthing for new vendored ones.

OK, I have a version that updates our vendored macros to more recent versions and makes a few changes to configure.ac itself to update our autoconf usage, and it generates a configuration file for me on my new install and also on an older autoconf 2.69 I have on a cloud system. 

https://github.com/pramsey/postgis/tree/master-autoconf-update

The configuration it generates seems to run and build for me here, but obviously this is our most platform-dependent piece so some extra tests before I drop it on master would be nice.

P