Re: ac macros and ac releases

[Ralf Wildenhues]

* Thomas Porschberg wrote on Fri, Feb 03, 2006 at 09:40:04AM CET:
> > * Thomas Porschberg wrote on Fri, Feb 03, 2006 at 08:35:13AM CET:
> > > 
> > > how can I find out when a certain autoconf macro was
> > > introduced by autoconf ?

> Just a thought:
> How about collect this information in a separate file
> and extend autoconf with an option --min-required-version
> which outputs the minimal required version for putting
> in AC_PREREQ ?

A couple of thoughts in return:
First, if you're currently writing configure.ac, then I suggest just
using AC_PREREQ(2.59) and be done with it: you definitely want other
developers (or advanced users) of your code to use the stuff with the
least known bugs, so you get as few bug reports about solved issues as
possible.

If OTOH you're writing a macro file *.m4 for installation and use in
third-party packages, your request makes much more sense: you may want
your macro to be as widely usable as possible.

Now, while I think it is error-prone to keep this information in
Autoconf in a separate file and maintain it by hand, it may be possible
to create this information automatically.  Hmm.
- extracting from `NEWS' may be too error-prone (or limit the author of
  the news entry),
- it may actually be useful to record this in the lib/*/*.m4 files
  itself, in the form of a traceable macro call.  That would require
  authors to add such an entry in the macro, though.
- Probably easiest would be for you to grab a bunch of Autoconf release
  tarballs, extract them all, and let grep hunt for the oldest mention.

The last method seems the easiest to me; and while it won't track macros
that have undergone incompatible changes, it would also be the least
amount of work.

Still, I'd suggest always using the latest version anyway.  Autoconf
release don't happen so often that users cannot be expected to keep up.
:->

Cheers,
Ralf