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.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Frama-c-discuss] [wp] unproved goals for strlen() function

>   
> /*@
>   loop assigns s;
>  */
>  while (*s++ !=((signed char) '\0'))
>  {
>     ;
>  }
>     This will discharge the following proof obligation:
> [wp] [Z3] Goal typed_strlen_loop_assign_part3.  
>   
>     But the post condition is still left unproved.

You cannot expect very much without a loop invariant ---
the only thing known after the loop right now is probably

  *(s - 1) == '\0'

(I haven't done C in a long time) if I remember correctly that
the ++ increments after the use in the expression...

Your postcondition probably does not follow from that alone...


Wolfram