[mingo-tip:master 1844/2335] arch/x86/entry/vdso/vdso32-setup.c:55:12: warning: no previous prototype for 'sysenter_setup'

[kernel test robot]

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git master
head:   85293bf3fca6d85608cff1447ce3097583f15fab
commit: b2730b92628ba23505877fc0c22a6c794bdcbe1e [1844/2335] headers/deps: x86/elf: Optimize <asm/elf.h> dependencies, split out <asm/elf_api.h>
config: i386-randconfig-a001-20220314 (https://download.01.org/0day-ci/archive/20220317/202203172022.xT4Voz39-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Ubuntu 9.4.0-1ubuntu1~20.04) 9.4.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git/commit/?id=b2730b92628ba23505877fc0c22a6c794bdcbe1e
        git remote add mingo-tip git://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git
        git fetch --no-tags mingo-tip master
        git checkout b2730b92628ba23505877fc0c22a6c794bdcbe1e
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/entry/vdso/ arch/x86/pci/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> arch/x86/entry/vdso/vdso32-setup.c:55:12: warning: no previous prototype for 'sysenter_setup' [-Wmissing-prototypes]
      55 | int __init sysenter_setup(void)
         |            ^~~~~~~~~~~~~~


vim +/sysenter_setup +55 arch/x86/entry/vdso/vdso32-setup.c

^1da177e4c3f41 arch/i386/kernel/sysenter.c        Linus Torvalds      2005-04-16  54  
a6c4e076ee4c1e arch/i386/kernel/sysenter.c        Jeremy Fitzhardinge 2007-05-02 @55  int __init sysenter_setup(void)
^1da177e4c3f41 arch/i386/kernel/sysenter.c        Linus Torvalds      2005-04-16  56  {
0a6d1fa0d2b48f arch/x86/entry/vdso/vdso32-setup.c Andy Lutomirski     2015-10-05  57  	init_vdso_image(&vdso_image_32);
^1da177e4c3f41 arch/i386/kernel/sysenter.c        Linus Torvalds      2005-04-16  58  
^1da177e4c3f41 arch/i386/kernel/sysenter.c        Linus Torvalds      2005-04-16  59  	return 0;
^1da177e4c3f41 arch/i386/kernel/sysenter.c        Linus Torvalds      2005-04-16  60  }
e6e5494cb23d19 arch/i386/kernel/sysenter.c        Ingo Molnar         2006-06-27  61  

:::::: The code at line 55 was first introduced by commit
:::::: a6c4e076ee4c1ea670e4faa55814e63dd08e3f29 [PATCH] i386: clean up identify_cpu

:::::: TO: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
:::::: CC: Andi Kleen <andi@xxxxxxxxxxxxxxxxx>

---
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