Re: [AD] gfxtest locks up with 4.0.0 + watcom

["Henrik Stokseth" <hstokset@xxxxxxxxxx>]

Sven Sandberg <svsa1977@xxxxxxxxxx> wrote:

> Something very strange must be going on: I can't reproduce it any more
> with gfxinfo, but I can with gfx_mode_select(). I get it with both vbeaf
> 1.1 and with 1.2, and in the latter case I'm sure I'm using S3. I now
> get a nice error message with gfxinfo:
>
>    Failed to retreive mode list. This might be because the driver
>    doesn't support mode fetching.
>
> Meaning that the `gfx_mode_list' retreived on line 105 of gfxinfo.c is
> NULL, which it can't have been when it crashed for me because it started
> printing graphics modes. (It probably was corrupted, or
> `gfx_mode_list->mode' was corrupted, or something very essential had
> been horribly overwritten before that.)

This is very useful to know, because it implies the problem lies within
FreeBe/AF not Allegro.  The VBE/AF driver does indeed support mode fetching,
but the actual list generation went very wrong, in such a way that
get_gfx_mode_list() wasn't able to return the error but rather crashed.
(endless loop, segmentation fault or whatever)

I am aware of problems with the stub driver, not reporting all modes in some
cases. It could be as simple as you run the program from a windowed dos
prompt instead of fullscreen. :o) So I will not be surprised if there are
problems with the S3 driver as well.

To assist in debugging can you send a compressed file containing the verbose
output from vesainfo, afinfo and gfxinfo? and if you can, a memory dump of
the mode list. (use can use gdb for it if you can return to text mode before
crash)

Sincerely Henrik Stokseth.
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