# Frama-C-discuss mailing list archives

This page gathers the archives of the old Frama-C-discuss archives, that was hosted by Inria's gforge before its demise at the end of 2020. To search for mails newer than September 2020, please visit the page of the new mailing list on Renater.

# [Frama-c-discuss] Frama-c-discuss Digest, Vol 32, Issue 12

```Oups sorry, my mistake :)

I finally succeeded !! Youhou.

Thanks a lot for your help Claude and David.

Arnaud

On Jan 25, 2011, at 5:17 PM, Claude Marche wrote:

> On 01/25/2011 02:02 PM, Arnaud Dieumegard wrote:
>> This helps !
>>
>> I manage to create some lemmas that allows me to prove the program:
>>
>> //@	lemma diff_point_prop: *(vect.a) != *(vect.Sum)&&  *(vect.b) != *(vect.Sum);
>>
>> or
>>
>> //@	lemma diff_prop: \forall UINT8 m, UINT8 n; 0<= m<  3&&  0<= n<  3 ==>  vect.a[m] != vect.Sum[n]&&  vect.b[m] != vect.Sum[n];
>>
>>
>
> Ouch! You confuse t[i] and t+i, this is certainly a mistake
>
> Anyway, you should not introduce lemmas but a predicate, e.g
>
> /*@ predicate valid_struct_S(struct S *s) =
>         \valid_range(s->a,0,2) && \valid_range(s->b,0,2) &&
>         \forall integer i,j; 0 <= i < 3 && 0 <= j < 3 ==> s->a+i != s->b+j ;
> */
>
> and then use
>
> /*@ requires valid_struct(&vect)
>       ....
>
> - Claude
>
>
>> I only need one of them to prove the program.
>> But a problem still exists:
>> I cannot prove the lemmas ! (But it's normal).
>>
>> Maybe it will be better to assume this in the function contract.
>>
>> Arnaud
>>
>> On Jan 25, 2011, at 11:19 AM, Claude Marche wrote:
>>
>>
>>> Hi all,
>>>
>>> Sorry but I have currently very little time to answer on such a question on a specific program
>>>
>>> Quick guess: Jessie poorly supports arrays embedded in structs and behaves like it was
>>> a pointer to another array, e.g.
>>>
>>> struct S {
>>>  int a[3]
>>> }
>>>
>>> handle as it was
>>>
>>> struct S {
>>>  int *a;
>>> }
>>>
>>>
>>> this explains why you need to specify \valid_range(a,0,2) even if it is obvious.
>>>
>>> Similarly, for two array fields a and b you should say something like
>>>
>>>
>>> forall i ,j  0<= i<= 3&&  0<= j<= 3 ==>   a+i != b+j
>>>
>>> to tell that a and b do not point to the same array
>>>
>>> Hope this helps,
>>>
>>> - Claude
>>>
>>>
>>> On 01/25/2011 09:20 AM, Arnaud Dieumegard wrote:
>>>
>>>> Hi all,
>>>>
>>>> I tried to prove my program without the struct and it succeeded !!!
>>>>
>>>> Maybe I have to create some logic specification for the struct ?
>>>> Or something to help the solver to understand what is on the structure.
>>>>
>>>> You could find enclosed the new c-code.
>>>>
>>>> I will now try to add some "structure specification".
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Arnaud
>>>>
>>>> On Jan 24, 2011, at 9:05 PM, David MENTRE wrote:
>>>>
>>>>
>>>>
>>>>> Hello,
>>>>>
>>>>> 2011/1/24 David MENTRE<dmentre at linux-france.org>:
>>>>>
>>>>>
>>>>>> Yes. Please find attached a variation of Arnaud's program that
>>>>>> compiles and runs under Jessie.
>>>>>>
>>>>>> I really don't understand why the assert in the for() loop of function
>>>>>> f() (VC 6.) is not proved.
>>>>>>
>>>>>> I'm using Frama-C Boron with Alt-Ergo 0.91.
>>>>>>
>>>>>>
>>>>> I still cannot prove the assertion with Frama-C Carbon beta 2, Why
>>>>> 2.28 and Alt-ergo 0.91[1]. The problem is probably in the assertion
>>>>> itself, but I don't see where.
>>>>>
>>>>> Regards,
>>>>> d.
>>>>>
>>>>> [1] And a slight modification on annotations, see attached C file.
>>>>> <dieumegard-case2.c>_______________________________________________
>>>>> Frama-c-discuss mailing list
>>>>> Frama-c-discuss at lists.gforge.inria.fr
>>>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss
>>>>>
>>>>>
>>>>
>>>> Cordialement,
>>>>
>>>> Arnaud Dieumegard
>>>> Research engineer
>>>> IRIT / ACADIE
>>>> arnaud.dieumegard at enseeiht.fr
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Frama-c-discuss mailing list
>>>> Frama-c-discuss at lists.gforge.inria.fr
>>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss
>>>>
>>>
>>> --
>>> Claude March?                          | tel: +33 1 72 92 59 69
>>> INRIA Saclay - ?le-de-France           | mobile: +33 6 33 14 57 93
>>> Parc Orsay Universit?                  | fax: +33 1 74 85 42 29
>>> 4, rue Jacques Monod - B?timent N      | http://www.lri.fr/~marche/
>>> F-91893 ORSAY Cedex                    |
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Frama-c-discuss mailing list
>>> Frama-c-discuss at lists.gforge.inria.fr
>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss
>>>
>> Cordialement,
>>
>> Arnaud Dieumegard
>> Research engineer
>> IRIT / ACADIE
>> arnaud.dieumegard at enseeiht.fr
>>
>>
>>
>>
>> _______________________________________________
>> Frama-c-discuss mailing list
>> Frama-c-discuss at lists.gforge.inria.fr
>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss
>>
>
>
> --
> Claude March?                          | tel: +33 1 72 92 59 69
> INRIA Saclay - ?le-de-France           | mobile: +33 6 33 14 57 93
> Parc Orsay Universit?                  | fax: +33 1 74 85 42 29
> 4, rue Jacques Monod - B?timent N      | http://www.lri.fr/~marche/
> F-91893 ORSAY Cedex                    |
>
>
>
>
>
>
>
>
> _______________________________________________
> Frama-c-discuss mailing list
> Frama-c-discuss at lists.gforge.inria.fr
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss

```