autoconf should print a warning notice when switching autoconf version

[dreamcat4]

Binary package hint: autoconf2.13

https://launchpad.net/ubuntu/karmic/i386/autoconf

The page says:

"This version of autoconf is not compatible with scripts meant for
 Autoconf 2.13 or earlier. If you need support for such scripts,
 you must also install the autoconf2.13 package."

If you choose install autoconf2.13 package in addition to the 2.64, then the default autoconf executable(s) are changed to the 2.13 versions. The newest autoconf2.64 becomes a secondary, and accessible as 'autoconf2.64'. When you uninstall 2.13, then the 2.64 is put back as the primary again. There are no messages printed to the user console.

The potential side effect is of course that someone unknowingly doing an "apt-get build-dep php5" might later on experience some unexpected autoconf issues.

So we'd like to change autoconf to it would do something like you might see on BSD operating systems:

During the package installation display a simple and clear notice.
 1) Explaining how the default system-wide autoconf is being changed between version y and version x
 2) The warning: possible implications / danger to leave it in this state.
 3) To give the command for the to run later on and revert the system back.

This request is related to bug #411890, however we believe that any/all package dependant on autoconf2.13 is affected.

[Scott James Remnant (Canonical) (canonical-scott)]

On Wed, 2009-08-12 at 11:06 +0000, dreamcat4 wrote:

> If you choose install autoconf2.13 package in addition to the 2.64, then
> the default autoconf executable(s) are changed to the 2.13 versions. The
> newest autoconf2.64 becomes a secondary, and accessible as
> 'autoconf2.64'. When you uninstall 2.13, then the 2.64 is put back as
> the primary again. There are no messages printed to the user console.
>
Not true.

When you install autoconf2.13, the default executable becomes a wrapper
that calls either autoconf2.13 or autoconf appropriately.

All autoconf 2.5x/2.6x versions have recommended that the input file be
called "configure.ac" (not configure.in) and required that the file
contain an appropriate AC_PREREQ() line.

This is sufficient to call the right script.

If you find a package that requires autoconf 2.5x/2.6x but uses
configure.in without AC_PREREQ, then that's a bug in that package not
autoconf.

 status invalid

Scott
--
Scott James Remnant
<email address hidden>

[dreamcat4 (dreamcat4)]

Wow - that's impressive! Very pleased to find out. Hopefully one day this information will get its way into the package description field, of the main autoconf package.

[dreamcat4 (dreamcat4)]

If it's a timestamps issue:

# When patching files like configure.in, aclocal.m4, configure can run twice. Later the compilation
# finishes with an error. If this happens use the debugging mode of the make command:
# `$(MAKE) --debug` instead of just `$(MAKE)` in the build targets below.

# Timestamps on the affected files can be fixed-up after patching (as quilt doesn't do it)
# For example to set the timestamps of (files...) equal to the "configure" timestamp.
# cd src-dir && touch -r configure files...

[dreamcat4 (dreamcat4)]

Sorry - that comment (#3) was meant for a different bug, #411890