mm/z3fold.c:280:37: warning: unused function 'handle_to_z3fold_header'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   1e2a199f6ccdc15cf111d68d212e2fd4ce65682e
commit: fc5488651c7d840c9cad9b0f273f2f31bd03413a z3fold: simplify freeing slots
date:   5 weeks ago
config: mips-randconfig-r033-20210119 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 22b68440e1647e16b5ee24b924986207173c02d1)
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=fc5488651c7d840c9cad9b0f273f2f31bd03413a
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout fc5488651c7d840c9cad9b0f273f2f31bd03413a
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 

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

All warnings (new ones prefixed by >>):

>> mm/z3fold.c:280:37: warning: unused function 'handle_to_z3fold_header'
   static inline struct z3fold_header long h)
   ^
   fatal error: error in backend: Nested variants found in inline asm string: ' .set push
   .set mips64r2
   .if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/atomic.h", .line = 154, $); 0x00 ) != -1)) : $))) ) && ( 0 ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif
   1: ll $1, $2 # atomic_fetch_sub
   subu $0, $1, $3
   sc $0, $2
   beqz $0, 1b
   .set pop
   move $0, $1
   '
   clang-12: error: clang frontend command failed with exit code 70 (use -v to see invocation)
   clang version 12.0.0 (git://gitmirror/llvm_project 22b68440e1647e16b5ee24b924986207173c02d1)
   Target: mipsel-unknown-linux-gnu
   Thread model: posix
   InstalledDir: /opt/cross/clang-22b68440e1/bin
   clang-12: note: diagnostic msg:
   Makefile arch block certs crypto drivers fs include init ipc kernel lib mm net scripts security sound source usr virt


vim +/handle_to_z3fold_header +280 mm/z3fold.c

4a3ac9311dac3850 Vitaly Wool 2019-11-30  278  
4a3ac9311dac3850 Vitaly Wool 2019-11-30  279  /* Returns the z3fold page where a given handle is stored */
4a3ac9311dac3850 Vitaly Wool 2019-11-30 @280  static inline struct z3fold_header *handle_to_z3fold_header(unsigned long h)
4a3ac9311dac3850 Vitaly Wool 2019-11-30  281  {
4a3ac9311dac3850 Vitaly Wool 2019-11-30  282  	return __get_z3fold_header(h, false);
4a3ac9311dac3850 Vitaly Wool 2019-11-30  283  }
4a3ac9311dac3850 Vitaly Wool 2019-11-30  284  

:::::: The code at line 280 was first introduced by commit
:::::: 4a3ac9311dac3850d1fbaa8bcad4cf10c4fc6296 mm/z3fold.c: add inter-page compaction

:::::: TO: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>
:::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
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