From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19442 invoked by alias); 2 Dec 2002 22:03:10 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 19348 invoked from network); 2 Dec 2002 22:03:09 -0000 Received: from unknown (HELO invisible-island.net) (68.49.156.7) by sources.redhat.com with SMTP; 2 Dec 2002 22:03:09 -0000 Received: (from tom@localhost) by invisible-island.net (8.10.2/8.10.2) id gB2M6b302253; Mon, 2 Dec 2002 17:06:37 -0500 Date: Mon, 02 Dec 2002 14:03:00 -0000 From: Thomas Dickey To: Alexandre Oliva Cc: Daniel Jacobowitz , Nathanael Nerode , gcc-patches@gcc.gnu.org, gdb-patches@sources.redhat.com, binutils@sources.redhat.com, dj@redhat.com, autoconf@gnu.org Subject: Re: (toplevel) introduce host subdir configuration in Makefile Message-ID: <20021202220637.GC528@bloatware.reston01.va.comcast.net> Reply-To: dickey@herndon4.his.com References: <20021128221312.GA20889@doctormoo> <20021202161822.GA11078@nevyn.them.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.3.27i X-SW-Source: 2002-12/txt/msg00042.txt.bz2 On Mon, Dec 02, 2002 at 02:39:49PM -0200, Alexandre Oliva wrote: > On Dec 2, 2002, Daniel Jacobowitz wrote: > > > You may already know this, but just to be careful I'll mention it > > anyway... it is not necessarily safe to configure more than one > > subdirectory at a time. One possibly gotcha is the updating of > > $cache_file. It isn't done atomically and so if you happen to have two > > subdirectories with the same (essentially) configure.in, and they > > happen to get started on an SMP system by make -j2 at (essentially) the > > same time, you can blow out the cache file. > > > This isn't entirely hypothetical. A similar thing happened in > > libiberty with two invocations of config.status. > > This was a bug in autoconf 2.13, that's fixed in autoconf 2.5x. arguable (as usual). 2.13 didn't pretend to support parallel make. 2.5x pretends to, but (as you note) config.cache isn't handled. So it appears more as a bug in 2.5x -- Thomas E. Dickey http://invisible-island.net ftp://invisible-island.net