Re: [PATCH 04/30] usb: misc: sisusbvga: sisusb_init: Mark all 'static const' arrays as __maybe_unused

[Lee Jones <lee.jones@linaro.org>]

On Fri, 03 Jul 2020, Joe Perches wrote:

> On Fri, 2020-07-03 at 18:41 +0100, Lee Jones wrote:
> > drivers/usb/misc/sisusbvga/sisusb_init.h is included by a few
> > source files.  Most of which do not use the majority of the
> > shared static const arrays which have been declared.  This
> > causes the build system to spew 100's of warnings.
> > 
> > Fixes the following W=1 kernel build warning(s) - and a whole lot more:
> > 
> >  In file included from drivers/usb/misc/sisusbvga/sisusb.c:54:
> >  drivers/usb/misc/sisusbvga/sisusb_init.h:695:34: warning: ‘SiSUSB_VCLKData’ defined but not used [-Wunused-const-variable=]
> >  695 | static const struct SiS_VCLKData SiSUSB_VCLKData[] = {
> >  | ^~~~~~~~~~~~~~~
> > [10's of lines snipped]
> >  drivers/usb/misc/sisusbvga/sisusb_init.h:206:28: warning: ‘SiS_VGA_DAC’ defined but not used [-Wunused-const-variable=]
> >  206 | static const unsigned char SiS_VGA_DAC[] = {
> >  | ^~~~~~~~~~~
> > [10's of lines snipped]
> >  drivers/usb/misc/sisusbvga/sisusb_init.h:171:29: warning: ‘ModeIndex_1280x1024’ defined but not used [-Wunused-const-variable=]
> >  171 | static const unsigned short ModeIndex_1280x1024[] = { 0x3a, 0x4d, 0x00, 0x65 };
> >  | ^~~~~~~~~~~~~~~~~~~
> > [10's of lines snipped]
> 
> They are not __maybe_unused, they _are_ used.

Potentially not by every consumer of this header file.

> I think these instead should be moved to where
> they are used instead of being declared in an
> #include file.

That works if they are being used by only one source file.

I'll look into it for this instance and get back to you.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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