Re: [gawk 3.1.5] *** glibc detected *** free(): invalid pointer:

[Aharon Robbins]

Greetings. Re this:

> Date: Thu, 19 Jan 2006 23:23:28 +0100
> From: Thomas Preissler <address@hidden>
> Subject: [gawk 3.1.5] *** glibc detected *** free(): invalid pointer:
> To: address@hidden
>
> Hello folks,
>
> I found a strange error using (g)awk 3.1.5:
>
> Any statement with gawk searching/checking a non existing file results
> in
>
> $ gawk '{ sum += $1 }; END { print sum }' file
> *** glibc detected *** free(): invalid pointer: 0x080923a0 ***
> zsh: abort      gawk '{ sum += $1 }; END { print sum }' file
>
> Dont hesitate to ask for any further questions. Thank you very much, I'll
> appreciate it very much.
>
>
> System: Debian testing, quite fresh, I update at about every 2 weeks.
> Kernel: 2.6.15 - Patches: mISDN (+zaptel... running asterisk)
>
> address@hidden:~/tmp> /lib/libc-2.3.5.so
> GNU C Library stable release version 2.3.5, by Roland McGrath et al.
> Copyright (C) 2005 Free Software Foundation, Inc.
> This is free software; see the source for copying conditions.
> There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
> PARTICULAR PURPOSE.
> Compiled by GNU CC version 4.0.3 20051201 (prerelease) (Debian 4.0.2-5).
> Compiled on a Linux 2.6.13 system on 2006-01-02.
> Available extensions:
>         GNU libio by Per Bothner
>         crypt add-on version 2.1 by Michael Glad and others
>         GNU Libidn by Simon Josefsson
>         linuxthreads-0.10 by Xavier Leroy
>         BIND-8.2.3-T5B
>         libthread_db work sponsored by Alpha Processor Inc
>         NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
> Thread-local storage support included.
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/libc/bugs.html>.
>
> Greets,
> Thomas

This is a known problem. The fix is attached. Thanks for the report!

Arnold
----------------------------
Fri Aug 12 13:10:33 2005  Arnold D. Robbins  <address@hidden>

        * io.c (iop_alloc): Only free `iop' if it was malloc'ed in
        the first place.

--- ../gawk-3.1.5/io.c  2005-07-26 21:07:43.000000000 +0300
+++ io.c        2005-08-12 13:10:28.000000000 +0300
@@ -2480,9 +2480,12 @@
 {
        struct stat sbuf;
        struct open_hook *oh;
+       int iop_malloced = FALSE;
 
-       if (iop == NULL)
+       if (iop == NULL) {
                emalloc(iop, IOBUF *, sizeof(IOBUF), "iop_alloc");
+               iop_malloced = TRUE;
+       }
        memset(iop, '\0', sizeof(IOBUF));
        iop->flag = 0;
        iop->fd = fd;
@@ -2495,7 +2498,8 @@
        }
 
        if (iop->fd == INVALID_HANDLE) {
-               free(iop);
+               if (iop_malloced)
+                       free(iop);
                return NULL;
        }
        if (isatty(iop->fd))