On Sat, Mar 23, 2024 at 7:16 PM Joe Perches <joe@xxxxxxxxxxx> wrote:
>
> On Sat, 2024-03-23 at 17:14 +1300, Barry Song wrote:
> > > > The patch titled
> > > > Subject: scripts: checkpatch: check unused parameters for function-like macro
> > > > has been added to the -mm mm-nonmm-unstable branch. Its filename is
> > > > scripts-checkpatch-check-unused-parameters-for-function-like-macro.patch
> > >
> > > Conceptually I don't disagree but I wonder what the false
> > > positive rate is.
> >
> > Hi Joe,
> >
> > If your concern is whether this script might produce inaccurate reports, I'm confident that
> > the false positive rate is 0%. Xining, please correct me if I'm mistaken.
>
> I presume it's low but non-zero.
>
> I think the false positives are going to be
> in some cases where a type is used as a macro
> argument in #ifdef/#else blocks
>
> #ifdef CONFIG_<FOO>
>
> #define foo(bar, baz, ...) \
> static inline func##bar(baz, ...) \
> { \
> bar baz = ... \
> ... \
> }
>
> #else
>
> #define foo(bar, baz, ...)
>
> #endif
>
> where it's not reasonably possible to use a
> static inline.
I do find some exceptions such as include/uapi/linux/const.h
#ifdef __ASSEMBLY__
#define _AC(X,Y) X
#define _AT(T,X) X
#else
#define __AC(X,Y) (X##Y)
#define _AC(X,Y) __AC(X,Y)
#define _AT(T,X) ((T)(X))
#endif
And include/video/trident.h
#if TRIDENTFB_DEBUG
#define debug(f, a...) printk("%s:" f, __func__ , ## a);
#else
#define debug(f, a...)
#endif
I'll check if Xining has some approach to detect this kind of ifdef/else/endif,
and remove those false positives.
