From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23465 invoked by alias); 12 Dec 2002 01:26:02 -0000 Mailing-List: contact gcc-prs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-prs-owner@gcc.gnu.org Received: (qmail 23448 invoked by uid 71); 12 Dec 2002 01:26:02 -0000 Date: Wed, 11 Dec 2002 17:26:00 -0000 Message-ID: <20021212012602.23447.qmail@sources.redhat.com> To: nobody@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: Daniel Jacobowitz Subject: Re: debug/1621: Debugging with complex numbers Reply-To: Daniel Jacobowitz X-SW-Source: 2002-12/txt/msg00691.txt.bz2 List-Id: The following reply was made to PR debug/1621; it has been noted by GNATS. From: Daniel Jacobowitz To: Jim Wilson Cc: Wolfgang Bangerth , "Joseph S. Myers" , bangerth@dealii.org, gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org Subject: Re: debug/1621: Debugging with complex numbers Date: Wed, 11 Dec 2002 20:22:45 -0500 On Wed, Dec 11, 2002 at 07:05:47PM -0500, Jim Wilson wrote: > About the $imag, $real stuff in the gcc/doc/extend.texi file... > The part about "None of the supported debug info formats..." is obsolete. > DWARF2 location descriptions can handle this easily, and this is already > supported in dwarf2out.c. Perhaps also DWARF, but I don't care enough to look > it up. The stabs hack of emitting two foo$imag and foo$real symbols is ugly > and should be discouraged. I don't think it makes any sense to teach gdb > about this hack. We should instead encourage use of DWARF2, which we are > already doing. I agree. > I tried writing a patch to make gcc use the Solaris 'R' stab letter extension. > > This brings up a number of questions. Sun only defined 3 float and 3 complex > float types. However, we have 7 float types and 6 complex float types. (They > should be the same, but that is a different problem.) Do we extend the > Solaris extension to meet our needs? Or fall back on the problematic 'r' > letter when we can't use 'R'? Extending 'R' might make us incompatible with > Sun if in the future Sun extends it too, so trying to discuss it with Sun is > a good idea. Or perhaps invent our own similar extension that won't conflict > with Sun? First of all, for floating point types we could just continue to use 'r'. It's not problematic in that case. On the other hand consistency is nice. I recommend emitting just the generic NF_COMPLEX and NF_FLOATING (?) for any of the unknown types. GDB only uses the type to determine if it is a floating or complex type, so that will suffice. -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer