Re: Weird irreproducible error

[Steve Heller <steve@...>]

On Mon, 08 Oct 2007 23:13:22 +0100, David Given <dg@cowlark.com>
wrote:

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>Steve Heller wrote:
>[...]
>> Yes, that would be a good approach if I had an indefinite amount of
>> time to find the problem, and it may in fact be the only way. Of
>> course, if it is a hardware problem, even that approch won't work.
>> However, clearly there is something seriously wrong somewhere either
>> in my code, in Lua, or in the Windows environment in which my code is
>> running.
>
>Get a copy of memtest86 (if you have an Ubuntu CD handy, just boot from that
>and there's an option to start it). That will do a thorough test of your RAM,
>if you're worried about hardware problems.

I'm doing that right now as a result of an earlier suggestion. I'm
also going to put my code on another computer and see if I can
replicate the problems there.

>Are you using any DirectX code as part of your program, by any chance? There's
>a DirectX bug (well, more of a designed in misfeature) that leaves the FPU in
>the wrong mode, which causes Lua's fast truncate-to-int code to produce
>incorrect results.

No, there is no DirectX code, or any C code at all for that matter.
There is nothing but I/O (disk and a little standard I/O to the
screen) and numeric/string calculations, all done in pure Lua.

Steve