tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.4.y
head:   3909e2374335335c9504467caabc906d3f7487e4
commit: defcc2b5e54a4724fb5733f802edf5dd596018b6 [7045/7049] lib/lz4: explicitly support in-place decompression
config: mips-randconfig-r036-20210706 (attached as .config)
compiler: mipsel-linux-gcc (GCC) 9.3.0
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
        # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git/commit/?id=defcc2b5e54a4724fb5733f802edf5dd596018b6
        git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
        git fetch --no-tags linux-stable-rc linux-5.4.y
        git checkout defcc2b5e54a4724fb5733f802edf5dd596018b6
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross 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 errors (new ones prefixed by >>):

   mipsel-linux-ld: arch/mips/boot/compressed/decompress.o: in function `LZ4_decompress_safe_withSmallPrefix':
   decompress.c:(.text+0x220): undefined reference to `memmove'
   mipsel-linux-ld: arch/mips/boot/compressed/decompress.o: in function `LZ4_decompress_fast_extDict':
   decompress.c:(.text+0x694): undefined reference to `memmove'
>> mipsel-linux-ld: decompress.c:(.text+0x774): undefined reference to `memmove'
   mipsel-linux-ld: arch/mips/boot/compressed/decompress.o: in function `LZ4_decompress_safe':
   decompress.c:(.text+0xb88): undefined reference to `memmove'
   mipsel-linux-ld: arch/mips/boot/compressed/decompress.o: in function `LZ4_decompress_safe_partial':
   decompress.c:(.text+0x1078): undefined reference to `memmove'
   mipsel-linux-ld: arch/mips/boot/compressed/decompress.o:decompress.c:(.text+0x12f8): more undefined references to `memmove' follow

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