From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-prs-return-33142-listarch-gcc-prs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 14900 invoked by alias); 15 Apr 2003 20:16:01 -0000
Mailing-List: contact gcc-prs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Archive: <http://gcc.gnu.org/ml/gcc-prs/>
List-Post: <mailto:gcc-prs@gcc.gnu.org>
List-Help: <mailto:gcc-prs-help@gcc.gnu.org>
Sender: gcc-prs-owner@gcc.gnu.org
Received: (qmail 14858 invoked by uid 71); 15 Apr 2003 20:16:01 -0000
Date: Tue, 15 Apr 2003 20:16:00 -0000
Message-ID: <20030415201601.14857.qmail@sources.redhat.com>
To: nobody@gcc.gnu.org
Cc: gcc-prs@gcc.gnu.org,
From: Wolfgang Bangerth <bangerth@ices.utexas.edu>
Subject: Re: middle-end/10415: allocated stack space non optimimal
Reply-To: Wolfgang Bangerth <bangerth@ices.utexas.edu>
X-SW-Source: 2003-04/txt/msg00712.txt.bz2
List-Id: <gcc-prs.sourceware.org>

The following reply was made to PR middle-end/10415; it has been noted by GNATS.

From: Wolfgang Bangerth <bangerth@ices.utexas.edu>
To: GrzegorzB <b.grzes@interia.pl>
Cc: gcc-gnats@gcc.gnu.org, <gcc-bugs@gcc.gnu.org>
Subject: Re: middle-end/10415: allocated stack space non optimimal
Date: Tue, 15 Apr 2003 15:15:25 -0500 (CDT)

 > Program test.c:
 > 
 > void f() {
 > 	char buf[3];
 > }
 > 
 > main() {
 > 	f();
 > }
 > 
 > I compile this:
 > gcc -S -o test test.c
 
 What happens if you switch on optimization? Is stack allocation better 
 then?
 
 [I think that the compiler will just optimize away everything in that 
 case, but you might prevent this by doing something like
 
 void p(char *x);
 void f() {
   char buf[3];
   p(buf);
 }
 
 and simply not defining f().]
 
 W.
 
 -------------------------------------------------------------------------
 Wolfgang Bangerth              email:            bangerth@ices.utexas.edu
                                www: http://www.ices.utexas.edu/~bangerth/