Re: distinguish automake 1.11 from 1.12+ at autoconf time

[Peter Johansson]

Hi Eric,

On 08/07/2012 09:36 AM, Eric Blake wrote:
> On 08/06/2012 05:29 PM, Peter Johansson wrote:
> > Hi,
> >
> > I'd like to distinguish automake 1.11 from 1.12 (or later) at autoconf
> > time. I wonder is there's any documented macro that was introduced in
> > 1.12 that I could use to m4_ifdef?
> If nothing else, the autoconf philosophy of feature checks being better
> than version checks should guide your decision here.
>
> What _specific_ feature are you using from 1.12 that wasn't present in
> 1.11?
Not really a feature but more of a bug that was fixed in 1.11.3 and 
described as follow in the 'NEWS':

The "deleted header file problem" for *.am files is avoided by stub
rules.  This allows `make' to trigger a rerun of `automake' also if
some previously needed `.am' file has been removed.
>   Or put another way, either your configure.ac works equally well
> with both versions (so you don't care which version), or there's
> something you do with 1.12 that doesn't work with 1.11 and therefore you
> are trying to make it conditional so that 1.11 can still process the
> rest of the file.  Determine that feature, and we are that much closer
> to helping you conditionalize your configure.ac to work with both versions.
I have a macro that generates .am snippets that are then included in 
Makefile.am. Currently the macro includes this in the output:

# stub rule to work around bug in Automake 1.11
\$(top_srcdir)/]$1[:

I was hoping to clean up this and only include it conditionally, but 
writing a feature test that runs at autoconf time seems more error 
prone. It's just a cosmetic fix anyway... and I should perhaps find 
better things to do;)

Cheers,
Peter