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[Frama-c-discuss] annotations and value analysis

Ok,

Good news. Thank you for improving this great tool!
I understand that it works fine with global vars and it will be working 
soon with \result. I guess it will be same with output parameters of the 
function (gest_index(int cmd, int* pindex). Can you confirm ?
And what about annotation on declaration of the function without 
definition ? Using annotation on a declaration function without 
definition could be very valuable. It could avoid us making some stubs 
for some function API that we don't have source code.
What is your opinion ?

regards,

St?phane


Pascal Cuoq a ?crit :
> Hello, St?phane,
>
>>   1/ does requires are checked by the value analysis considering the 
>> calling context ?
>>   2/ does requires are hypothesis for the body of the function ?
>>   3/ does the ensures are checked by the value analysis ?
>>   4/ does the ensures of a called function are taken into account for 
>> the analysis of the caller ?
>> Using the tool, I would answer yes for all except for 4/. 
>
> In fact, it is "yes" for all 4 in the development version
> of Frama-C. On the other hand, the value analysis
> does not yet support \result in post-conditions.
>
> Changing your example thus:
>
> int R;
>
> /*@
>   @ requires 0<=cmd<5;
>   @ ensures  0<=\result<200;
>   @ ensures  0 <= R < 200 ;
>   @*/
> int get_index(int /* in */ cmd)
> {
>   int v = cmd;
>   int ret = (unsigned int)Frama_C_interval(0,1000);
>   R = ret;
>   return ret;
> }
>
> void main(x)
> {
>   get_index(x);
>   return R;
> }
>
> you get:
>
> [value] Values for function main:
>           R ? [0..199]
>
> Part of the restructuration necessary to handle \result
> in post-conditions has already been done, but it is
> not complete at this time.
>
> Pascal
>

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