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Subject: Re: gnat and heap size
References: <1001442590.557811@news.drenet.dnd.ca>
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Date: 27 Sep 2001 19:48:18 +0200
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Gerald Kasner <Gerald.Kasner@Physik.Uni-Magdeburg.DE> writes:

> > 
> > > 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).
> > 
> 
> RedHat Linux 6.2 on a sparc sun 4 ultra, gnat 3.12p :
> 
> No output. 

The output of this program will depend on the heap layout of the
particular os you are running on.  By increasing the size of b (to a
few thousand) and adding a few thousand to the index in a I write to I
was able to reproduce the output in linux-x86 with gnat 3.13p as well.

-Erik
-- 
/d{def}def/m{mul}d/a{add}d/q{repeat}d/y 1 d 300{/x 1 d 600{/c x 600 div 4 m 2
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