arch/mips/boot/compressed/../../lib/bswapsi.c:5:22: warning: no previous prototype for function '__bswapsi2'

arch/mips/boot/compressed/../../lib/bswapsi.c:5:22: warning: no previous prototype for function '__bswapsi2'

[kernel test robot]

Hi Masahiro,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   e2ae0d4a6b0ba461542f0fd0ba0b828658013e9f
commit: f78b25ee922ef6faf59a258af1b9388ca894cfd9 mips: decompressor: do not copy source files while building
date:   6 weeks ago
config: mips-buildonly-randconfig-r003-20211226 (https://download.01.org/0day-ci/archive/20211226/202112261150.2zpinfBb-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 0c553cc1af2e4c14100df6cf4a6fc91987e778e6)
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 mips cross compiling tool for clang build
        # apt-get install binutils-mips-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f78b25ee922ef6faf59a258af1b9388ca894cfd9
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout f78b25ee922ef6faf59a258af1b9388ca894cfd9
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash

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 >>):

   In file included from arch/mips/boot/compressed/bswapsi.c:2:
>> arch/mips/boot/compressed/../../lib/bswapsi.c:5:22: warning: no previous prototype for function '__bswapsi2' [-Wmissing-prototypes]
   unsigned int notrace __bswapsi2(unsigned int u)
                        ^
   arch/mips/boot/compressed/../../lib/bswapsi.c:5:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   unsigned int notrace __bswapsi2(unsigned int u)
   ^
   static 
   1 warning generated.


vim +/__bswapsi2 +5 arch/mips/boot/compressed/../../lib/bswapsi.c

1ee3630a3e57f3 Ralf Baechle 2015-09-29   4  
aedcfbe06558a9 Harvey Hunt  2016-05-25  @5  unsigned int notrace __bswapsi2(unsigned int u)
1ee3630a3e57f3 Ralf Baechle 2015-09-29   6  {
1ee3630a3e57f3 Ralf Baechle 2015-09-29   7  	return (((u) & 0xff000000) >> 24) |
1ee3630a3e57f3 Ralf Baechle 2015-09-29   8  	       (((u) & 0x00ff0000) >>  8) |
1ee3630a3e57f3 Ralf Baechle 2015-09-29   9  	       (((u) & 0x0000ff00) <<  8) |
1ee3630a3e57f3 Ralf Baechle 2015-09-29  10  	       (((u) & 0x000000ff) << 24);
1ee3630a3e57f3 Ralf Baechle 2015-09-29  11  }
1ee3630a3e57f3 Ralf Baechle 2015-09-29  12  

:::::: The code at line 5 was first introduced by commit
:::::: aedcfbe06558a9f53002e82d5be64c6c94687726 MIPS: lib: Mark intrinsics notrace

:::::: TO: Harvey Hunt <harvey.hunt@imgtec.com>
:::::: CC: Ralf Baechle <ralf@linux-mips.org>

---
0-DAY CI Kernel Test Service, Intel Corporation
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