Re: [PATCH] Coccinelle: doubletest: reduce side effect false positives

From: Masahiro Yamada
Date: Mon Aug 13 2018 - 03:30:44 EST


2018-08-04 1:32 GMT+09:00 Julia Lawall <Julia.Lawall@xxxxxxx>:
> Ensure that the cited expression is not a function call or an
> assignment to reduce the chance of false positives.
>
> Slightly modify the warning message to indicate another source
> of false positves.
>
> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>
>


Applied to linux-kbuild. Thanks!


(Please send a reminder
if there are more coccinelle patches I missed.)




> ---
> scripts/coccinelle/tests/doubletest.cocci | 34 ++++++++++++++++++++++--------
> 1 file changed, 26 insertions(+), 8 deletions(-)
>
> diff --git a/scripts/coccinelle/tests/doubletest.cocci b/scripts/coccinelle/tests/doubletest.cocci
> index 78d74c2..7af2ce7 100644
> --- a/scripts/coccinelle/tests/doubletest.cocci
> +++ b/scripts/coccinelle/tests/doubletest.cocci
> @@ -1,6 +1,7 @@
> /// Find &&/|| operations that include the same argument more than once
> -//# A common source of false positives is when the argument performs a side
> -//# effect.
> +//# A common source of false positives is when the expression, or
> +//# another expresssion in the same && or || operation, performs a
> +//# side effect.
> ///
> // Confidence: Moderate
> // Copyright: (C) 2010 Nicolas Palix, DIKU. GPLv2.
> @@ -20,20 +21,37 @@ position p;
> @@
>
> (
> -* E@p
> - || ... || E
> + E@p || ... || E
> |
> -* E@p
> - && ... && E
> + E@p && ... && E
> )
>
> -@script:python depends on org@
> +@bad@
> +expression r.E,e1,e2,fn;
> +position r.p;
> +assignment operator op;
> +@@
> +
> +(
> +E@p
> +&
> + <+... \(fn(...)\|e1 op e2\|e1++\|e1--\|++e1\|--e1\) ...+>
> +)
> +
> +@depends on context && !bad@
> +expression r.E;
> +position r.p;
> +@@
> +
> +*E@p
> +
> +@script:python depends on org && !bad@
> p << r.p;
> @@
>
> cocci.print_main("duplicated argument to && or ||",p)
>
> -@script:python depends on report@
> +@script:python depends on report && !bad@
> p << r.p;
> @@
>
>



--
Best Regards
Masahiro Yamada