Re: [cocci] __free() attribute inhibits matching?

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

> It seems that the mere presence of the "__free" attribute breaks matching:
>
> $ cat test.c
> static void why(void)
> {
>         u64 *rates_64 __free(kfree) = NULL;
>         rates_64 = kcalloc(count, sizeof(*rates_64), GFP_KERNEL);
> }


Questionable test result (with the software combination “Coccinelle 1.3-00083-g4093aad2d”):
Markus_Elfring@Sonne:…/Projekte/Coccinelle/Probe> spatch --parse-c example_by_Kees_Cook-20250317.c
…
BAD:!!!!!         u64 *rates_64 __free(kfree) = NULL;
…
maybe 10 most problematic tokens
…
NB total files = 1; perfect = 0; pbs = 1; timeout = 0; =========> 0%
nb good = 0,  nb passed = 1 =========> 12.50% passed
nb good = 0,  nb bad = 7 =========> 12.50% good or passed



> $ cat match.cocci
> @replace@
> expression THING, COUNT;
> expression GFP;
> @@
>
> -       kcalloc(COUNT, sizeof(*THING), GFP)
> +       kzalloc_objs(*THING, COUNT, GFP)

Would another SmPL code variant be occasionally helpful?

@replacement@
expression THING, COUNT, GFP;
@@
-kcalloc
+kzalloc_objs
 (
-COUNT,
-sizeof(
        *THING
-      )
+, COUNT
 , GFP
 )


Regards,
Markus