Re: please correct my ugly hack

[Ralf Corsepius]

On Wed, 2005-06-01 at 13:45 -0400, Dan Manthey wrote:
> On Wed, 1 Jun 2005, Ralf Corsepius wrote:
> 
> > On Wed, 2005-06-01 at 18:33 +0200, Stepan Kasal wrote:
> >
> > > I think the best solution is to drop caching from programs.m4.
> > Only over my dead body ;-)
> >
> > > Caching was invented mainly for expensive tests which involve
> > > calling a compiler, which can be really slow.
> > No, caching had been invented for faster interaction of several
> > configure scripts (CONFIG_SUBDIRS) in large source trees.
> 
> Can't you just `export PROG' in the root configure to pass the found
> value to the sub-configures. 
Well, to some extend yes, but no in general:

* We are talking about several dozens of values. This makes applying
environment variables very unhandy.

* Consider cross compilation. In this case you are building several sub-
trees of a source-tree with different settings.

* Environment variables impose side-effects. They are hard to trace and
easy to miss.

Ralf