Re: [linux-next:master 11942/12503] drivers/video/fbdev/aty/atyfb_base.c:180:6: warning: no previous prototype for function 'aty_st_lcd'

[Randy Dunlap <rdunlap@infradead.org>]

On 2/24/21 12:42 PM, Nick Desaulniers wrote:
> On Wed, Feb 24, 2021 at 12:03 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>>
>> On 2/24/21 4:46 AM, kernel test robot wrote:
>>> Hi Randy,
>>>
>>> FYI, the error/warning still remains.
>>>
>>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
>>> head:   577c283560fe8a81a23a95654c6d13e8412d22f1
>>> commit: bfa5782b9caa26f93f42ad79804e1f75a1ce9f18 [11942/12503] fbdev: atyfb: add stubs for aty_{ld,st}_lcd()
>>> config: arm64-randconfig-r004-20210223 (attached as .config)
>>> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project f14a14dd2564703db02f80c00db8ae492b594f77)
>>> reproduce (this is a W=1 build):
>>>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>>>         chmod +x ~/bin/make.cross
>>>         # install arm64 cross compiling tool for clang build
>>>         # apt-get install binutils-aarch64-linux-gnu
>>>         # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=bfa5782b9caa26f93f42ad79804e1f75a1ce9f18
>>>         git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>>>         git fetch --no-tags linux-next master
>>>         git checkout bfa5782b9caa26f93f42ad79804e1f75a1ce9f18
>>>         # save the attached .config to linux build tree
>>>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
>>>
>>> If you fix the issue, kindly add following tag as appropriate
>>> Reported-by: kernel test robot <lkp@intel.com>
>>>
>>> All warnings (new ones prefixed by >>):
>>>
>>>>> drivers/video/fbdev/aty/atyfb_base.c:180:6: warning: no previous prototype for function 'aty_st_lcd' [-Wmissing-prototypes]
>>>    void aty_st_lcd(int index, u32 val, const struct atyfb_par *par)
>>>         ^
>>>    drivers/video/fbdev/aty/atyfb_base.c:180:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>>>    void aty_st_lcd(int index, u32 val, const struct atyfb_par *par)
>>>    ^
>>>    static
>>>>> drivers/video/fbdev/aty/atyfb_base.c:183:5: warning: no previous prototype for function 'aty_ld_lcd' [-Wmissing-prototypes]
>>>    u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>>>        ^
>>>    drivers/video/fbdev/aty/atyfb_base.c:183:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>>>    u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>>>    ^
>>>    static
>>>    2 warnings generated.
>>>
>>
>> These 2 functions are also used/usable (depending on CONFIG options) in
>> mach64_ct.c so they can't be static.
>>
>> AFAIK, we don't make functions have different qualifiers depending on
>> config options.
> 
> Is there a shared header included by both mach64_ct.c and atyfb_base.c
> you could provide a declaration in, that way should the definition
> change we'd catch such a change in order to not break the callers?
> 

atyfb.h:

#if defined(CONFIG_PMAC_BACKLIGHT) || defined (CONFIG_FB_ATY_GENERIC_LCD) || \
defined (CONFIG_FB_ATY_BACKLIGHT)
extern void aty_st_lcd(int index, u32 val, const struct atyfb_par *par);
extern u32 aty_ld_lcd(int index, const struct atyfb_par *par);
#endif

so it's already there unless the .config did not include those #ifdef CONFIG_s.
I'll recheck that.


-- 
~Randy