[EMAIL PROTECTED] (S.D.Mechveliani) writes:
> The following pretends to reveal a bug in ghc-0.29-linux-386.
>
> The program reduces the matrix mM to the staircase form by the
> Gauss method over the coefficient domain = C = Int, Integer.
>
>
> result( mM ) =
>
> [... big matrix deleted ...]
>
>
> result( mM_without_last_row_and_last_column ) = -- the right one
>
>
> [... another big matrix deleted ...]
>
> Bug in arithmetics ??
Sadly, I've forgotten everything I every knew about Gaussian
elimination, staircases and everything else.
Can you explain in plain English what the bug is?
What calculation is being performed?
What is the correct answer?
What answer are you getting?
Why do you believe the bug is in the compiler (and not in your code)?
(It's usually easier to answer this question if you simplify your
program down to the point where the result can be calculated by
hand or, at least, apply it to a very small piece of input data.)
What assumptions are you making about the underlying machine arithmetic
(eg 32 bits 2s-complement? unbounded precision? etc)
--
Alastair Reid Yale Haskell Project Hacker
[EMAIL PROTECTED] http://WWW.CS.Yale.EDU/homes/reid-alastair.html
ps In case anyone's curious why a Yale dude is sending this message...
I like to try out ghc bug reports on Hugs as well and I had no idea
where to begin with this bug report.
