[Cocci] for sequence

[Julia Lawall]

On Sat, 13 Nov 2010, Vasiliy Kulikov wrote:

> Hi,
> 
> I cannot understand why it happens:
> 
> @@
> expression x;
> expression E;
> identifier free ~= "^kfree$\|^kput$\|^put_device$\|^input_unregister_device$";
> @@
> 
> *free(x);
>  ... when != x
> (
>   x = E
> |
> * x
> )
> 
> --- main.c  2010-11-13 14:16:31.000000000 +0300
> +++ /tmp/cocci-output-18580-98aa90-main.c   2010-11-13
> 14:18:27.000000000 +0300
> @@ -16,8 +16,6 @@ main(int argc, char **argv)
>      void *x;
>      void *y;
>  
> -    for (x = &y; x == &y; x = &y)
> -        kfree(x);

Spatch doesn't know about the order of evaluation between the subterms of 
a for loop header.  You can avoid the problem by making your disjunction:

(
  for(...;...;x = E) S
|
  x = E
|
* x
)

where S is a statement metavariable.

julia