From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264450AbTLQQGd (ORCPT ); Wed, 17 Dec 2003 11:06:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264451AbTLQQGd (ORCPT ); Wed, 17 Dec 2003 11:06:33 -0500 Received: from roc-24-93-20-125.rochester.rr.com ([24.93.20.125]:34553 "EHLO mail.kroptech.com") by vger.kernel.org with ESMTP id S264450AbTLQQGb (ORCPT ); Wed, 17 Dec 2003 11:06:31 -0500 Date: Wed, 17 Dec 2003 11:11:14 -0500 From: Adam Kropelin To: Greg KH Cc: linux-hotplug-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH] udev-009: Allow build with empty EXTRAS Message-ID: <20031217111114.A3931@mail.kroptech.com> References: <20031216220406.A23608@mail.kroptech.com> <20031217083100.GA2126@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20031217083100.GA2126@kroah.com>; from greg@kroah.com on Wed, Dec 17, 2003 at 12:31:00AM -0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 17, 2003 at 12:31:00AM -0800, Greg KH wrote: > On Tue, Dec 16, 2003 at 10:04:06PM -0500, Adam Kropelin wrote: > > Need to let the shell expand $EXTRAS so it can properly detect an empty > > list. Without this patch, the build fails whenever $EXTRAS is empty. > > $ export EXTRAS= > $ make > $ set | grep EXTRA > EXTRAS= > $ > > I can't duplicate this problem at all. Someone else once reported it on > the linux-hotplug-devel list, with much the same fix up patch, but later > said they couldn't reproduce it either. > > What version of make are you using? It's actually the version of bash that's important. Prior to 2.05a, bash was unable to handle for loops with empty words lists. From the bash-2.05a changelog: p. `for' loops now allow empty word lists after `in', like the latest POSIX drafts require. So bash-2.05 dies on... for test in ; do echo $test ; done ...while bash-2.05a accepts it just fine. Both versions can handle this case if the shell itself does the expansion that results in the empty list. So that's where my workaround came from. --Adam