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[Frama-c-discuss] Loop invariants



Hollas Boris (CR/AEY1) wrote:
> Hello,
> 
> consider the following while loop:
> 
> 
> // loop invariant i <= n;
> while(some condition) {
>   P
>   i++;
> }
> 
> 
> Assume that
> - the loop invariant holds and
> - P is a block of code that does not modify i.
> Hence, i < n holds in P. 
 >
 >Does Jessie know that when analysing this kind of loop? Ie, is Jessie 
able to conclude  i <= n \land (some condition) ==> i < n ?

Sure if condition is (i < n) or anything that implies (i < n), but 
otherwise no. But if you are able to prove that the invariant holds, 
then certainly you should be able to prove //@ assert i<n; either before 
or after P, no ?

What is your condition exactly ?

> - Boris
> 
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