Re: [RFC] Fix source path lookup immediately after substitute-path

[Daniel Jacobowitz <drow@false.org>]

On Tue, Sep 22, 2009 at 03:03:02PM -0700, Joel Brobecker wrote:
> Before I answer your question, I just wanted to point out that I did
> review the patch, and that it seemed good to me (progress, even) :).

Yes, thank you :-)

> > last_source_visited is the direct cause of the problem I've fixed with
> > this patch.  External circumstances, like "dir" or "cd" or "set
> > substitute-path" have to be able to invalidate the cache, so it has to
> > be accessible outside the function.  Have I misunderstood?
> 
> The comments for last_source_visited are saying that this variable
> is meant to help us avoid printing the file-does-not-exist error
> message more than once if we repeateadly try to list that same file.
> However, in practice, this variable is also used to cache the result
> of the lookup.

Oh, I understand now.  In the specific case of a failed lookup, it's
used as a cache.  It's never used to cache a successful lookup - if
!last_source_error, we'll always call openp again.

I agree that this is not particularly important either way.  Thanks
for explaining!

-- 
Daniel Jacobowitz
CodeSourcery