Re: [Cocci] xusb-tegra186: Adding a function call behind a label with SmPL?

[Markus Elfring <Markus.Elfring@web.de>]

>> @addition@
>> expression object;
>> @@
>>  object = kzalloc(...)
>>  ... when any
>>  device_unregister(...);
>>  out:
>> +kfree(object);
>>  return ERR_PTR(...);
>
> There is no reason why a patch should be generated in this case.

We come along different software development views also for this use case.
I tend still to interpret some of my source code search patterns in other directions.


> As you should know well, A ... B only matches in a transformation case
> if every path from A leads to code matching B.

Now I imagine that an explanation of such information can become more interesting
also based on the applied technologies as a knowledge background.
https://github.com/coccinelle/coccinelle/blob/ed1eb8e06f800739d3992158d36945c0c4c6f0c7/docs/manual/cocci_syntax.tex#L860

https://en.wikipedia.org/wiki/Computation_tree_logic#Relations_with_other_logics


> That is not the case in your example.

The shown SmPL script can probably indicate that a return statement should occasionally
be executed if a jump to it (according to the label “out” for example) was performed before
(in one if branch).

The following simple transformation approach seems to work also in the way
which I expected somehow initially.

@addition@
expression object;
@@
 object = kzalloc(...)
 ... when exists
 device_unregister(...);
 out:
+kfree(object);
 return ERR_PTR(...);


Can any extensions for the software documentation help to make the application
of the semantic patch language easier and safer finally?

Regards,
Markus
_______________________________________________
Cocci mailing list
Cocci@systeme.lip6.fr
https://systeme.lip6.fr/mailman/listinfo/cocci