Date: Fri, 19 Sep 2008 09:17:17 -0700 (PDT) From: Unga <unga888@yahoo.com> To: freebsd-questions@freebsd.org Subject: Segmentation fault when free Message-ID: <37804.54110.qm@web57007.mail.re3.yahoo.com>
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Hi all
I'm running FreeBSD 7 on i386. I have a C program compiled with gcc 4.2.1 20070719.
Logically my program is:
char *a;
char *b;
char *c;
while (cond)
{
a = f1(); /* malloc() and send a string */
b = f2(); /* malloc() and send a string */
c = (char *) malloc(strlen(a) + strlen(b) + 1);
c[0] = '\0';
strcat(c, a);
strcat(c, b);
free(a);
free(b);
}
When it executes free(b), my program exits with Segmentation fault: 11. The free(a) executes well.
The problem is with free(b). Even swap free(b) first and free(a) next, it still crashes at free(b).
If I comment out free() lines, further down the program, first few characters of one string get dropped when executes a completely unrelated line.
How could I bit more narrow down the problem?
Many thanks in advance.
Kind regards
Unga
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