Re: [RFC] Update to current automake/autoconf/libtool versions.

[Klee Dienes <klee@apple.com>]

On Thursday, December 5, 2002, at 06:19 PM, Alan Modra wrote:

> On Thu, Dec 05, 2002 at 02:55:38PM -0800, Ian Lance Taylor wrote:
>> Perhaps --enable-maintainer-mode could be extended to specify a PATH
>> to use to find the tools.
>
> It would need to be on a per-directory basis.  Something like
>
> --enable-maintainer-mode=\
> "gdb:/usr/local/000227/bin,libstdc++-v3:/usr/local/oldauto/bin,*:yes"

What if the rules generated by --enable-maintainer-mode were to pass a 
version number to each of the tools when using them to re-generate 
files?  The version number passed would be the same version number used 
to generate the existing version of the generated files.  Then the 
autotools could either dispatch to the correct version of the tool 
based on the version number, or
perhaps generate an error if the version numbers did not match.  In 
order to upgrade the generated files in a directory to a newer version, 
the user would have to explicitly run autoreconf or run he appropriate 
autotools directly.

This would make it a lot harder for a maintainer to accidentally use 
the wrong version of an autotool when regenerating files in a 
directory.  It would also make it possible to write a top-level script 
that would explicitly re-generate all of the files in a tree with 
explicitly specified versions (or at least verify that the versions 
being used were correct).

Regardless of how we choose to do it, though, I think it's important 
that maintainers be able to update individual subdirectories to newer 
versions of the autotools independently of each other (even if the way 
we choose to do that is to say "don't run global 
--enable-maintainer-mode, and be aware of the versions of the autotools 
you are using").  If we don't, the bar for updating versions of 
autotools is just too high.  Trying to coordinate a simultaneous 
upgrade of even a simple change across the combined src+gcc repository 
is a huge amount of work --- if that's the only way to do upgrades, it 
seems much more likely that the upgrades will tend to not get done.  
The thought of even *touching* sid is daunting to me, much less the 
thought of trying to claim that I've changed all of its Makefiles and 
understand the changes.