From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21226 invoked by alias); 24 Jul 2003 14:56:57 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 21215 invoked from network); 24 Jul 2003 14:56:54 -0000 Received: from unknown (HELO hotmail.com) (64.4.16.82) by sources.redhat.com with SMTP; 24 Jul 2003 14:56:54 -0000 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Thu, 24 Jul 2003 07:56:53 -0700 Received: from 203.200.20.226 by law11-oe25.law11.hotmail.com with DAV; Thu, 24 Jul 2003 14:56:53 +0000 X-Originating-IP: [203.200.20.226] X-Originating-Email: [mohanlaljangir@hotmail.com] From: "mohanlal jangir" To: References: <3F1FEF06.20507@drexel.edu> <20030724144832.GA326@nevyn.them.org> Subject: Re: gdb shows source line multiple times before executing !! Date: Thu, 24 Jul 2003 14:56:00 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Message-ID: X-OriginalArrivalTime: 24 Jul 2003 14:56:53.0734 (UTC) FILETIME=[D1EC6860:01C351F3] X-SW-Source: 2003-07/txt/msg00299.txt.bz2 > Because GCC splits the code for the line into multiple parts. Part of > the line has executed when you step over it, but it may not be > immediately obvious how. For instance, given: > a = b + c; > the first time you step over it may load b and c from memory; the > second time may add them; and only the third will store the result into > a. hmm... but sometimes it behaves even worse. For example there are two lines a = b + c; d = e + f; then first gdb shows line a = b + c; then d = e + f and then again a = b + c. And while showing d = e + f first time if I try to print value of a, it will be some uninitialised (that indicates that a = b + c has not been executed). Then on next "next" command I will see line a = b +c again and then valute of a will be correct one. > > mohanlal jangir wrote: > > > >While single stepping with gdb, quite frequently I see sorce lines > appearing > >multiple times i.e. gdb shows some line that will be executed on command > >"next", but that is actully not. After next "next" command, I see same > line > >appearing. This happens two or three times and then finally that line is > >executed.