Re: [RFC] getting rid of the config.guess/sub problem when bootstrapping new ports/systems

[Warren Young]

On 5/17/2013 13:05, Henrique de Moraes Holschuh wrote:
> It would have been really useful if autofoo used whatever is in
> /usr/share/misc, unless there is a config.sub.override or
> config.guess.override file

You're starting from an assumption that autotools are installed on all 
systems where you would want to build an autoconfiscated package.

For example, on Cygwin and FreeBSD, a C compiler is optional, and 
installing it doesn't drag in the autotools.

All you're supposed to need to build an autoconfiscated package are 
sh(1), make(1), and the compiler for whatever language the package's 
source code is in.

I think you have the seed of a good idea here, though.

What if configure behaves just like it currently does unless it sees 
that config.{guess,sub}[.override] aren't present at all?  It can then 
go looking for default versions in the usual system locations.

OS package creation tools could offer a per-package flag in the 
package's configuration (.spec, .ebuild, .cygport, debian/...) that 
tells it it is safe to remove shipped config.{guess,sub} files from the 
tarball when building the source package, and that it should autoreconf 
the package to get a configure script and Makefile.in that's aware of 
this new behavior.  The idea here is that binary package building 
workstations *can* be assumed to have autotools installed.

It would also be useful if generated configure scripts supported a 
--no-local-guess flag which forces it to look for system versions even 
if it finds them in the same directory as the configure script.  That 
way a tarball can *ship* with config.{guess,sub}, but when a package 
maintainer knows the system versions are going to work better, it can 
pass that flag without autoreconf'ing the package.

You might think that unnecessarily fiddly, but it's based on an 
experience of mine just last month.  I was trying to build something 
that shipped with outdated config.{guess,sub} files, but I couldn't 
autoreconf it because its configure.ac file was *also* written in a 
style so obsolescent that autoconf refused to cope with it.  The package 
creation tool "helpfully" tried overwriting config.{guess,sub} but it 
did so with versions that were still too old, so even if I overwrote 
them ahead of time, it clobbered my fixes.

That "--no-local-guess" flag would have saved me some aggravation.

Yes, I realize such behavior won't save me for another 3+ years, if I 
have my way.  I'd rather have these features painlessly in the future 
than break a hundred thousand tarballs so I can have these features now.