Re: caching variables

[Ralf Wildenhues]

* Eric Blake wrote on Sat, Sep 12, 2009 at 04:43:01AM CEST:
> According to Sam Steingold on 9/11/2009 2:54 PM:
> > however, this way I will be testing variables which have never been set.
> > is this OK?
> > (I understand that unless I set -u, shell will not barf, but I was
> > wondering if that was considered bad style in aitoconf).
> 
> Autoconf _expects_ to be run with set +u, and exploits uninitialized
> variables.

Even with set -u, the && should have short-circuit semantics, so you
shouldn't ever test any variable which hasn't been set before, if you
order the tests in the right way.

> It would be a _lot_ of work to support set -u.

Actually, I have used it from time to time for debugging purposes,
but more for the libtool script.

Cheers,
Ralf