Re: have a look at this proggie, please.
H. Peter Anvin (hpa@transmeta.com)
20 Nov 1998 01:32:54 GMT
Followup to: <Pine.GSO.4.05.9811191517550.4315-100000@montezuma.acc.umu.se>
By author: David Weinehall <tao@acc.umu.se>
In newsgroup: linux.dev.kernel
> >
> > Why the surprise? You've generated an exception #0, which Intel
> > called "divide by zero" in early IA processor manuals, but now call
> > "divide error". It is raised by any divide where the result overflows.
>
> That's NOT an divide by zero...
>
> Output:
>
> -2147483648 * -1 = -2147483648
> Floating exception
> ^^^^^^^^^^^^^^^^^^
>
> Quite obviously, -MAXINT-1 * -1 is too large for an integer to hold (by
> one), but it should *NOT* report a floating exception... Right?!
>
No. SIGFPE is the reported exception for integer division overflow or
division by zero. Illogical, perhaps, but that's the way it is.
-hpa
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