Re: Possible Bug (core dump) in awk 3.0.6

[Aharon Robbins]

> From: Dan Bornstein <address@hidden>
> Date: Wed, 15 Nov 2000 15:48:00 -0800 (PST)
> To: address@hidden
> Subject: Possible Bug (core dump) in awk 3.0.6
>
> Hi. I just found this bug when running awk 3.0.6. I have verified that the
> problem does not occur with awk 3.0.4, but these were on two different
> systems with different other libraries as well. In particular, I tested awk
> 3.0.4 on a RedHat 6.2 installation and awk 3.0.6 on a RedHat 7 installation
> (both Intel x86). The core dump makes it look to me like it could be a
> problem with libc, but I don't really know how to trace it much further
> than I've already done.
>
> [....]
>
> #!/bin/sh
>
> awk 'END { for (i in goodies) delete baddies[goodies[i]]; print baddies[i] }' 
> milk

Much thanks for the bug report.  Here is an unofficial patch.

Arnold

*** ../gawk-3.0.6/awk.y Sun Jul 16 18:29:50 2000
--- awk.y       Tue Nov 21 16:20:22 2000
***************
*** 398,405 ****
                 * Check that the body is a `delete a[i]' statement,
                 * and that both the loop var and array names match.
                 */
!               if ($8->type == Node_K_delete
                    && $8->rnode != NULL
                    && strcmp($3, $8->rnode->var_value->vname) == 0
                    && strcmp($5, $8->lnode->vname) == 0) {
                        $8->type = Node_K_delete_loop;
--- 398,406 ----
                 * Check that the body is a `delete a[i]' statement,
                 * and that both the loop var and array names match.
                 */
!               if ($8 != NULL && $8->type == Node_K_delete
                    && $8->rnode != NULL
+                   && $8->rnode->type == Node_var
                    && strcmp($3, $8->rnode->var_value->vname) == 0
                    && strcmp($5, $8->lnode->vname) == 0) {
                        $8->type = Node_K_delete_loop;
--
Aharon (Arnold) Robbins --- Pioneer Consulting Ltd.     address@hidden
P.O. Box 354            Home Phone: +972  8 979-0381    Fax: +1 603 761-6761
Nof Ayalon              Cell Phone: +972 51  297-545    (See www.efax.com)
D.N. Shimshon 99785     Laundry increases exponentially in the
ISRAEL                  number of children. -- Miriam Robbins