Re: calling autoreconf and minimizing rebuilds

[Stepan Kasal]

Hello,

On Thu, Sep 07, 2006 at 10:18:56AM -0700, David Byron wrote:
> Seems like my helper Makefile would be more helpful if I ran autoreconf -vi 
> just
> before executing make even if the Makefile has already been generated.

Well, I would do the minimal:
run autoreconf -vi is configure does not exist
run configure is Makefile does not exist
make

I think one can depend on the makefiles to refresh the generated files
as soon as a source is modified.

About the question of upgrading autotools:
the project contains all generated files; so if you upgrade autoconf,
but you don't touch your sutoconfigury sources, then the generated
files are not refreshed, they still use the previous version, and
there is no problem with it.

But if you upgrade some of the autotools, and make decides to upgrade
some of the generated files, but not all, you may get into troubles.
Most people do not investigate it and run `autoreconf -fvi' to fix
it; after all, this does not happen every year.  ;-)

But some people do investigate these problems, so I guess we proceed
towards fixing the problem.  At least, Automake does some check, so
even though you still have to fix the situation manually, the error
messages should be descriptive.

* David Byron wrote on Thu, Sep 07, 2006 at 07:03:20PM CEST:
>
> What's involved in making autoreconf smart enough to deal with autotools
> upgrades without using -f?

Well, these days, it's up to the individual tools to verifi that the
output is up-to-date.

It seems that aclocal always computes a new aclocal.m4, but writes it
only if it differs from aclocal.m4.  But aclocal.m4 contains the
version of Automake, so this is sufficient to handle Automake
updates.

As soon as aclocal.m4 is refreshed, autoconf and automake will notice
it, and refresh their output files, too.

If some of the *.m4 files brought by gettext or libtool are updated,
then aclocal notices that, refreshes aclocal.m4, and all is well.

And the latest development relase of aclocal (1.9b, a beta for 1.10)
also engraves the Autoconf version to aclocal.m4, so it will handle
Autoconf upgrades, too.

Then there is GNU gettext: I believe the whole point of `autopoint'
is to update the copied files, so that should be OK, too.
And it the gettext's

Finally, there is libtool: I guess that libtoolize should refresh the
generated files if libtool was updated.  Ralf, is that true?

To sum up, install Automake 1.9b and rest assured that all is handled.
Then just watch for bugs and report them.  ;-)

Have a nice day,
        Stepan Kasal