PANIC-crashes with INFORMIX-ONLINE

I'm posting this in behalf of one of our partners. Please reply to me (matthias.apitz@softcon.de) and Schneider@HRZ.Uni-Dortmund.De. Thx in advance. matthias -- We observed several PANIC-crashes with INFORMIX-ONLINE Version 7.12C1X2 on SNI's Reliant UNIX 5.43. The error messages and the restart protocol (in online.log) were like this: 21:32:42 Checkpoint Completed: duration was 0 seconds. 21:38:51 Pool = 0x2267e010, Pool name = 12, Blkhdr = 0x22682bdc 21:38:51 Block magic is 24, expecting 24 21:38:51 Possible memory block trailer corruption 21:38:51 mtshpool.c, line 2549, thread 36, proc id 16201, Condition Failed (CHECK_ALLOC_BLOCK), In (mt_shm_free) Thread(36, sqlexec, 0, 3). 21:38:51 PANIC: Attempting to bring system down Thu Feb 6 21:39:23 1997 21:39:23 DR: DRAUTO is 0 (Off) 21:39:24 INFORMIX-OnLine Initialized -- Shared Memory Initialized. 21:39:24 Physical Recovery Started. 21:39:24 Physical Recovery Complete: 0 Pages Restored. 21:39:24 Logical Recovery Started. 21:39:27 Logical Recovery Complete. 0 Committed, 0 Rolled Back, 0 Open, 0 Bad Locks 21:39:27 Dataskip is now OFF for all dbspaces 21:39:27 On-Line Mode 21:39:27 Checkpoint Completed: duration was 0 seconds. Up to now in all cases the both values "Black magic" and "expecting" were absolutely identical (here = 24). The following script served as a "reliable crash-trigger": select d02bnr, d02bg from d02ben where d02bnr < 19960000 ; I started the script in the dbaccess-dialog-environment and the command "isql - crashtest" in a ksh, both with the same result. To produce a crash, I had to start this select-command twice. The first run is ok. But starting it again immediately after finishing the first run - to display the first hits again - results in a crash. The script behaved this way on two different databases (in different dbspaces) with absolutely different data (but the same table-structure). I varied the script and the data and found, that with a reduced comparing limit (199600) the very same script runs absolutely save. But increasing to 1996000 results in a crash as well. The variable d02bnr is defined as varchar(12,0), but it is filled only with pure numbers (fixed-length strings with leading zeros). SQL does an "implicit type conversion" to compare the string with the integer. When I used a string instead, INFORMIX didn't crash. This was save: select d02bnr, d02bg from d02ben where d02bnr < "19960000" ; I created a new table - a twin in the same dbspace with identical structure but slightly different names for key-variables and indexes. The table was filled with the same data, but INFORMIX didn't crash - under no circumstances. I played the game with INFORMIX-ONLINE V7.12.UC1X2, Reliant UNIX 5.43 B0045, RM600 3/640 R4000 (SNI-mips-machine). Any ideas? Feb 7 1997 Schneider@HRZ.Uni-Dortmund.De