Re: gnat and heap size

[Erik Johannessen <erik.johannessen@kongsberg.com>]

Erik Johannessen <erik.johannessen@kongsberg.com> writes:

> The fun part here is that you can stay within the bounds you've
> declared for the array, but access memory outside of the area
> allocated for the array.  If you've got other data on the heap after
> the array you'll get some interesting bugs. :)
> 
> The following code demonstrates the problem

[...]

> Compiled with gnat-3.14a1 on sparc-solaris2.6 I get:
> > ./matrix
> Found 42 at index  42 in b

And in this example the array bounds for b can be overwritten as well
(since they are stored right before the first array element).

-Erik
-- 
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sub d/z y 300 div 2 m 1 sub d/r 0 d/i 0 d/t 0 d{t 1 le{/n r r m i i m sub c a
d/b 2 r m i m z a d/r n d/i b d r r m i i m a 16 gt{exit}if} {exit}ifelse/t t 
.01 a d}loop t setgray x y moveto 1 1 rlineto stroke/x x 1 a d}q /y y 1 a d}q