From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28048 invoked by alias); 23 Jan 2019 04:00:59 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 27719 invoked by uid 89); 23 Jan 2019 04:00:44 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=1.1 required=5.0 tests=BAYES_50,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,KAM_SHORT,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=no version=3.3.2 spammy=HX-HELO:sk:mail-ed, Joshi, EXP-1, debuggable X-HELO: mail-ed1-f48.google.com Received: from mail-ed1-f48.google.com (HELO mail-ed1-f48.google.com) (209.85.208.48) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 23 Jan 2019 04:00:40 +0000 Received: by mail-ed1-f48.google.com with SMTP id y56so562857edd.11 for ; Tue, 22 Jan 2019 20:00:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=/DwUon2RhKT9n5cccBN5IGP5jlU69qIn4/wkAnbrY/U=; b=d+P4Ldcy5dtVf8/vixFbUmQzhbhJrGUywTZjvRA4rB2x8qPuH9PLXNIZdC1f4h5y/b f5h1Gj9XbVfQpJvJyhRIUyOHe/mnoI9gOgo1cc7A2BIHdaI2jutPgc3sn9+Opv3gx9r/ g9jOVn8EkLiFwT/Sg/+qfUqVgEnm728Lge86TiNzohr98DWJPhyjgnKyH4LxDgbXS2rE H+b/36uPfvlcGbNbDkSNjkuGm79XYezeutbUzWo9Bl9M1eF3Vbrky1bqZsZqVHLRBjbX x5hhauFnAZlkBOglLqh1S7wT9Z4VSLx0APxIoXsdRFtBxTUGliUcHhMOpp2aQ4W4U9Kv y8lQ== MIME-Version: 1.0 References: In-Reply-To: From: Tejas Joshi Date: Wed, 23 Jan 2019 04:00:00 -0000 Message-ID: Subject: Re: About GSOC. To: gcc@gcc.gnu.org Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2019-01/txt/msg00183.txt.bz2 I built gcc as a debuggable compiler as given using -g3. I am using gdb and loaded the cc1 using: gdb --args cc1 with output as: Successfully loaded GDB hooks for GCC But I really dont know how to inspect a file like real.h (real_value)/real.c? Thanks. -Tejas On Wed, 23 Jan 2019 at 08:28, Tejas Joshi wrote: > > > differ. (It's the unoptimized, stage1 cc1 that should be run under a > > debugger. See for more details.) > > Hello. > I normally configure GCC by (as you told) > > /configure --enable-languages=c,c++ --disable-bootstrap --disable-multilib > > And further as told in > > make STAGE1_CXXFLAGS="-g -O0" all-stage1 > > but instead of -g to use -g3 is suggested for making macros debuggable > and then use GDB. > May I proceed the same? > > On Tue, 22 Jan 2019 at 04:33, Joseph Myers wrote: > > > > On Tue, 22 Jan 2019, Tejas Joshi wrote: > > > > > the number like nan or normal in the functions. Though, attributes of > > > struct real_value are pretty unclear to me regarding to the number it > > > represents. (Am I right within this grasp?). > > > > It may be helpful to run the compiler under a debugger to examine how > > particular real numbers are represented in real_value - that should help > > answer questions such as what endianness is used for the significand, or > > whether floating point values with a given exponent are in the range > > [2^EXP, 2^(EXP+1)) or [2^(EXP-1), 2^EXP), where conventions commonly > > differ. (It's the unoptimized, stage1 cc1 that should be run under a > > debugger. See for more details.) > > > > And of course contribute comments in real.h once you've determined the > > answers - because there are such areas where conventions about > > representation of floating-point numbers commonly differ, it's > > particularly valuable to have such comments because even someone familiar > > with floating-point won't know which convention has been chosen by this > > code in GCC. > > > > -- > > Joseph S. Myers > > joseph@codesourcery.com