From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21972 invoked by alias); 11 Jun 2007 17:00:06 -0000 Received: (qmail 21909 invoked by uid 22791); 11 Jun 2007 17:00:04 -0000 X-Spam-Check-By: sourceware.org Received: from py-out-1112.google.com (HELO py-out-1112.google.com) (64.233.166.181) by sourceware.org (qpsmtpd/0.31) with ESMTP; Mon, 11 Jun 2007 17:00:00 +0000 Received: by py-out-1112.google.com with SMTP id a25so845627pyi for ; Mon, 11 Jun 2007 09:59:59 -0700 (PDT) Received: by 10.64.199.8 with SMTP id w8mr7551584qbf.1181581197608; Mon, 11 Jun 2007 09:59:57 -0700 (PDT) Received: by 10.64.76.7 with HTTP; Mon, 11 Jun 2007 09:59:57 -0700 (PDT) Message-ID: Date: Mon, 11 Jun 2007 17:00:00 -0000 From: kdsfinger@gmail.com To: gdb@sourceware.org Subject: gdb breakpoint problem MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2007-06/txt/msg00079.txt.bz2 hi, all I am new to gdb and have trouble in setting the breakpoint. The problem is, the program does not stop at some of the breakpoints. I am using gdb6.6 in centos4.4. Here is the detail. =================================== /* sample.c -- Sample C program to be debugged with ddd */ #include #include static void shell_sort(int a[], int size){ int i, j; int h = 1; do { h = h * 3 + 1; } while (h <= size); do { h /= 3; for (i = h; i < size; i++){ int v = a[i]; for (j = i; j >= h && a[j - h] > v; j -= h) a[j] = a[j - h]; if (i != j) a[j] = v; } } while (h != 1); } int main(int argc, char *argv[]){ int *a; //line 24 int i; //line 25 a = (int *)malloc((argc - 1) * sizeof(int)); // line 26 for (i = 0; i < argc - 1; i++) a[i] = atoi(argv[i + 1]); shell_sort(a, argc); for (i = 0; i < argc - 1; i++) printf("%d ", a[i]); printf("\n"); free(a); return 0; } ======================================== gcc -g -o sample sample.c gdb sample GNU gdb 6.6 Copyright (C) 2006 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i686-pc-linux-gnu"... Using host libthread_db library "/lib/tls/libthread_db.so.1". (gdb) break 24 Breakpoint 1 at 0x804850b: file sample.c, line 24. (gdb) info break 1 Num Type Disp Enb Address What 1 breakpoint keep y 0x0804850b in main at sample.c:24 (gdb) run 2 4 6 3 5 7 Starting program: /home/amdx2/drive2/cpp/testddd/sample 2 4 6 3 5 7 Breakpoint 1, main (argc=7, argv=0xbff515c4) at sample.c:26 26 a = (int *)malloc((argc - 1) * sizeof(int)); ------------------------- As you can see, the program did not stop at the breakpoint on line24. It stops at line26. If I add another breakpoint on line25, this 2nd breakpoint is skipped as well and the program stops at line26. Why is that? How can I correct it? On my own program which is rather big, it got the same problem. When I use info break xxx, it sometimes point to a different place in "What". For example, I placed the breakpoint in main line 100, but the "what" points to other functions in different line. As the result, these breakpoints never work. I changed my gcc flags with combinations of -glevel -olevel, the problem did not solve. Thanks for your comments. zl2k