Re: [PATCH v4 2/2] scripts: checkpatch: check unused parameters for function-like macro

From: Mac Xu
Date: Sun Mar 31 2024 - 19:21:57 EST



> On Sun, 2024-03-31 at 13:46 +0000, Mac Xu wrote:
> > > On Thu, 2024-03-28 at 15:21 +1300, Barry Song wrote:
> > > > From: Xining Xu <mac.xxn@xxxxxxxxxxx>
> > > >
> > > > If function-like macros do not utilize a parameter, it might result in a
> > > > build warning. In our coding style guidelines, we advocate for utilizing
> > > > static inline functions to replace such macros. This patch verifies
> > > > compliance with the new rule.
> > > []
> > > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> >
> []
> > > It seems this logic is a bit redundant to existing
> > > code and might be better added in the block that starts
> > >
> > > (line 6026)
> > > # check if any macro arguments are reused (ignore '...' and 'type')
> > >
> > > as that already does each param in a #define and
> > > ignores ... and type
> >
> > Hi Joe,
> >
> > Thank you for your comments with insights, as you said, code block of line 6026 is a better place to
> > place this new logic, as it already handles the logic I'd wanted like extracting, splitting and trimming
> > the arguments, excluding the trailing comments etc.
> >
> > By placing the logic in the new place, code duplicates are reduced.
> >
> > Here's my new code (inserted from line 6044):
> > +# check if this is an unused argument
> > + if ($define_stmt !~ /\b$arg\b/) {
> > + WARN("UNUSED_ARG_IN_MACRO",
> Perhaps
> WARN("MACRO_ARG_UNUSED",
> ...
>
> to better match the others above it in the block:
>
> CHK("MACRO_ARG_REUSE",
> and
> CHK("MACRO_ARG_PRECEDENCE",
>
> Other than that trivial bit, seems ok.

Sure, updated, thank you!

+# check if this is an unused argument
+if ($define_stmt !~ /\b$arg\b/) {
+ WARN("MACRO_ARG_UNUSED",
+ "Argument '$arg' is not used in function-like macro\n" . "$herectx");
+}

Regards,
Xining