[masahiroy-kbuild:modpost-wip 26/40] kernel/foo.c:13:6: warning: no previous prototype for 'foo_register'

[masahiroy-kbuild:modpost-wip 26/40] kernel/foo.c:13:6: warning: no previous prototype for 'foo_register'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git modpost-wip
head:   d37b0bfa125f03dbeb16ee01480bd6d8a69e7ac0
commit: 70ec473283598a6d32c3a36014bae676a5feb39b [26/40] [please ignore] kbuild local test (please ignore 0-day bot report)
config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20220807/202208072106.I92R3WA8-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/commit/?id=70ec473283598a6d32c3a36014bae676a5feb39b
        git remote add masahiroy-kbuild https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git
        git fetch --no-tags masahiroy-kbuild modpost-wip
        git checkout 70ec473283598a6d32c3a36014bae676a5feb39b
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> kernel/foo.c:13:6: warning: no previous prototype for 'foo_register' [-Wmissing-prototypes]
      13 | void foo_register(void)
         |      ^~~~~~~~~~~~
>> kernel/foo.c:22:13: warning: no previous prototype for 'hoge' [-Wmissing-prototypes]
      22 | void __init hoge(void)
         |             ^~~~
--
>> kernel/bar.c:10:5: warning: no previous prototype for 'bar' [-Wmissing-prototypes]
      10 | int bar(int *x)
         |     ^~~


vim +/foo_register +13 kernel/foo.c

    12	
  > 13	void foo_register(void)
    14	{
    15		bar(&foo.y);
    16	}
    17	
    18	struct table {
    19		void (*callback)(void);
    20	};
    21	
  > 22	void __init hoge(void)
    23	{}
    24	EXPORT_SYMBOL(hoge);
    25	

-- 
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https://01.org/lkp