Re: [PATCH v2 34/59] checkpatch: dont warn about unused macro arg on empty body

[Louis Chauvet]

Le 20/03/2025 à 19:52, Jim Cromie a écrit :
> we currently get:
>    WARNING: Argument 'name' is not used in function-like macro
> on:
>    #define DRM_CLASSMAP_USE(name)  /* nothing here */
>
> Following this advice is wrong here, and shouldn't be fixed by
> ignoring args altogether; the macro should properly fail if invoked
> with 0 or 2+ args.
>
> cc: Andy Whitcroft <apw@xxxxxxxxxxxxx>
> cc: Joe Perches <joe@xxxxxxxxxxx>
> cc: Dwaipayan Ray <dwaipayanray1@xxxxxxxxx>
> cc: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>
> Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>

Reviewed-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>

> ---
>   scripts/checkpatch.pl | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 7b28ad331742..0c4f578ea6e7 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -6037,7 +6037,7 @@ sub process {
>   				}
>   
>   # check if this is an unused argument
> -				if ($define_stmt !~ /\b$arg\b/) {
> +				if ($define_stmt !~ /\b$arg\b/ && $define_stmt) {
>   					WARN("MACRO_ARG_UNUSED",
>   					     "Argument '$arg' is not used in function-like macro\n" . "$herectx");
>   				}

--
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com