Re: How to develop a random number generation device

On Sep 19, 2:03 pm, Rich Grise <r...@xxxxxxxxxxx> wrote:
Static analysis tools can only find some bugs. Some code has to be
stepped through to see if it ever gets stuck or goes into a loop. I'm
thinking of things like:

while (X > 1) do
if (X is even) X = X/2;
else X = 3 * X + 1;

It is really hard to see whether for some values of X this sticks in a
loop or not.

It didn't take me any time at all to see that this has no bounds checking;
what happens if someone passes X=1.42857 to it?

X is an integer. Most other readers understood what I meant by the
comment.


This little example-oid was clearly written by one of those lame
programmer-wannabees who keeps sniveling "All Software Has Bugs And
There's Nothing You Can Do About It!!!" as an excuse for his
incompetence/laziness.

No, it is an example of a proof that you can't check your code by
running it through a compiler, or static checker, no matter how clever
that code may be unless you are willing to have the compiler take
weeks to compile. Problems of this sort require either a new method
be found or that all cases be explored.



Cheers!
Rich


.

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