From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24080 invoked by alias); 25 Mar 2003 22:23:37 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 24046 invoked from network); 25 Mar 2003 22:23:36 -0000 Received: from unknown (HELO mail.cs.umn.edu) (128.101.33.102) by sources.redhat.com with SMTP; 25 Mar 2003 22:23:36 -0000 Received: from bose.cs.umn.edu (bose.cs.umn.edu [128.101.35.195]) by mail.cs.umn.edu (Postfix) with ESMTP id 1CE321155F; Tue, 25 Mar 2003 16:23:36 -0600 (CST) Received: by bose.cs.umn.edu (Postfix, from userid 818) id BFE59326F; Tue, 25 Mar 2003 16:23:35 -0600 (CST) To: Cc: Zack Weinberg , "Kaveh R. Ghazi" , mark@codesourcery.com, gcc@gcc.gnu.org, gdr@integrable-solutions.net Subject: Re: Converting to ISO C89 References: From: Raja R Harinath Date: Tue, 25 Mar 2003 22:40:00 -0000 In-Reply-To: ('s message of "Tue, 25 Mar 2003 15:03:39 -0800 (PST)") Message-ID: User-Agent: Gnus/5.090017 (Oort Gnus v0.17) Emacs/21.3.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2003-03/txt/msg01583.txt.bz2 writes: > On Tue, 25 Mar 2003, Raja R Harinath wrote: [snip stage2 bootstrap with C++ compiler] >> I was thinking more about optimization: ensure that there's no >> abstraction penalty for using a C++ compiler on C code, and that both >> the C and C++ compilers exploit the same optimization opportunities. >> >> - Hari > > IIRC, C code compiled as C++ needs to carry around stack unwinding > information whereas C code compiled as C does not. > > Therefore, the abstraction penalty cannot be zero in terms of code size. Since we know it is C code, we can compile with -fno-exceptions. The size of the CFG should not be significantly larger since there should be no additional flows of control (hidden or otherwise). - Hari -- Raja R Harinath ------------------------------ harinath@cs.umn.edu