From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: wierd problem in Allegro 3.0
Date: Tue, 14 Apr 1998 18:19:06 -0400
Organization: Two pounds of chaos and a pinch of salt.
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Count Razumovsky wrote:
> 
> I'm experiencing a very strange problem in Allegro that I hope someone
> can shed some light on.  I'm using Allegro 3.0 with the newest versions
> of djgpp and rhide.  All my programs compile and link fine but when I
> try to run the executable the program dies and I get this message:
> 
> Shutting down Allegro
> Exiting due to signal SIGSEGV
> Page fault at eip=000028b8, error=0004
> .
> .       (* very cryptic letters and numbers in here *)
> .
> call frame traceback EIPS:
> 0x000028b8
> 0x0002d20a
> 
> What does that mean?? Only some of the program's which use allegro give
> me this error, not all of them.  Has anyone seen this error before and
> if so how do you fix it???      Thanks.

Chapter 9.2 of the DJGPP Frequently Asked Questions list discusses the
crash traceback and how to use it in detail, so I suggest you read it. 
Basically, all those numbers and letters represent the state of your
program at the point where it crashed.  You can use the information to
figure out where and why the crash occurred, so you can fix it.

Steps:

1) compile your program with the '-g' flag to add full debugging
information.
2) When the crash traceback is on the screen, type "symify myprog.exe",
or whatever the name of your program's executable is.  You'll see the
function names, source files, and line numbers where the crash occurred.
3) Go to that location in your source code and look for things like
uninitialized or NULL pointer dereferences, stack overflows, array
bounds overflows, and the like.

If you're still confused, look in chapter 12 of the FAQ for information
about debugging programs, and/or post a sample of your code here so we
can look at it ourselves.

-- 
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|      John M. Aldrich       | "A woman is not property, and hus-   |
|       aka Fighteer I       | bands who think otherwise are living |
|   mailto:fighteer AT cs DOT com   | in a dreamworld."                    |
| http://www.cs.com/fighteer |                - Lazarus Long        |
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