From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22337 invoked by alias); 4 Aug 2002 19:43:11 -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 22329 invoked from network); 4 Aug 2002 19:43:06 -0000 Received: from unknown (HELO localhost.redhat.com) (24.112.240.27) by sources.redhat.com with SMTP; 4 Aug 2002 19:43:06 -0000 Received: from ges.redhat.com (localhost [127.0.0.1]) by localhost.redhat.com (Postfix) with ESMTP id 8D0B93DD7; Sun, 4 Aug 2002 15:42:55 -0400 (EDT) Message-ID: <3D4D83BF.1080504@ges.redhat.com> Date: Sun, 04 Aug 2002 12:43:00 -0000 From: Andrew Cagney User-Agent: Mozilla/5.0 (X11; U; NetBSD macppc; en-US; rv:1.0.0) Gecko/20020802 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Theodore Roth Cc: gdb-patches@sources.redhat.com Subject: Re: [RFC] fix for avr_skip_prologue() References: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2002-08/txt/msg00086.txt.bz2 > Hi, > > Before I commit this, I wanted to know if this is the correct fix or just > an evil hack side-stepping the some other problem. > > The problem shows up when I set a break point on a simple function as > such: > > (gdb) b foo_simple > > If foo_simple() has no prologue, the break point is set at the _end_ of > the function (effectively the return insn). > > If this fix is acceptable, is it too late to make it into the 5.2 branch? I don't think your change is any worse than many other *_skip_prologue() tweaks. A typical skip_prologue() function is an accumulation of heuristics and a lot of comments. > 2002-07-19 Theodore A. Roth > > * gdb/avr-tdep.c(avr_skip_prologue): Fix to return the correct pc. > > Index: gdb/avr-tdep.c > =================================================================== > RCS file: /cvs/src/src/gdb/avr-tdep.c,v > retrieving revision 1.4 > diff -u -p -r1.4 avr-tdep.c > --- gdb/avr-tdep.c 17 Jun 2002 23:32:27 -0000 1.4 > +++ gdb/avr-tdep.c 19 Jul 2002 18:33:30 -0000 > @@ -995,7 +995,12 @@ avr_skip_prologue (CORE_ADDR pc) > { > sal = find_pc_line (func_addr, 0); > > - if (sal.line != 0 && sal.end < func_end) > + /* troth/2002-70-19: For some very simple functions, gcc doesn't > + generate a prologue and the sal.end ends up being the insn (2 bytes) > + before func_end (the address of the next func). By adjusting > + func_end, we can catch these functions and return the correct pc. */ I'd just also mention that the instruction in question is ``return'' and is two bytes long. > + if (sal.line != 0 && sal.end < (func_end-2)) > return sal.end; > } enjoy, Andrew >