[Cocci] Matching variable declarations

[Valentin Schneider <valentin.schneider@arm.com>]

Hi,

I'm trying to change the type of variables that match a certain rule.
Abstracting away this specific rule and only looking at coming up with a
rule to match variable declarations, I have a few newbie questions.

Say I want to replace all long declarations into ints, this simple rule
seems to be working fine:

---
@@
identifier var;
type T = long;
expression E;
@@

(
- T var;
+ int var;
|
- T var = E;
+ int var = E;
)
---

I tried to write it as
---
- T
+ int
var
? = E
;
---
but that doesn't seem to be a valid syntax.


Now, I'd like to match declarations of several variables in a single
statement as well.

Say I want to get something like

- long a, b = 2, c, d = 42, e;
+ long a, b = 2, c, e;
+ int d = 42;

 (match on longs initialized to 42)

My current attempt is
---
@@
identifier var;
type T = long;
expression L, R;
@@

T L,
- var = 42
R;
+ int var;
---
But that isn't valid either. How should I go about writing this sort of
rule?

If you're curious, there's more context about what I'm trying to achieve
at:

https://lore.kernel.org/lkml/20190902210558.GA23013@avx2/

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