tree:   https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git pending
head:   fa809cc6feedcd2575b63def7135dfaf066266bb
commit: ed37942d3f53ae55c077704f6a8e6306d96169f6 [20/38] libnvdimm/labels: Add address-abstraction uuid definitions
config: parisc-randconfig-r016-20210814 (attached as .config)
compiler: hppa64-linux-gcc (GCC) 11.2.0
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/cxl/cxl.git/commit/?id=ed37942d3f53ae55c077704f6a8e6306d96169f6
        git remote add cxl-cxl https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git
        git fetch --no-tags cxl-cxl pending
        git checkout ed37942d3f53ae55c077704f6a8e6306d96169f6
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=parisc 

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 >>):

>> drivers/nvdimm/label.c:749:25: warning: no previous prototype for 'uuid_to_nvdimm_cclass' [-Wmissing-prototypes]
     749 | enum nvdimm_claim_class uuid_to_nvdimm_cclass(uuid_t *uuid)
         |                         ^~~~~~~~~~~~~~~~~~~~~


vim +/uuid_to_nvdimm_cclass +749 drivers/nvdimm/label.c

   747	
   748	/* CXL labels store UUIDs instead of GUIDs for the same data */
 > 749	enum nvdimm_claim_class uuid_to_nvdimm_cclass(uuid_t *uuid)
   750	{
   751		if (uuid_equal(uuid, &nvdimm_btt_uuid))
   752			return NVDIMM_CCLASS_BTT;
   753		else if (uuid_equal(uuid, &nvdimm_btt2_uuid))
   754			return NVDIMM_CCLASS_BTT2;
   755		else if (uuid_equal(uuid, &nvdimm_pfn_uuid))
   756			return NVDIMM_CCLASS_PFN;
   757		else if (uuid_equal(uuid, &nvdimm_dax_uuid))
   758			return NVDIMM_CCLASS_DAX;
   759		else if (uuid_equal(uuid, &uuid_null))
   760			return NVDIMM_CCLASS_NONE;
   761	
   762		return NVDIMM_CCLASS_UNKNOWN;
   763	}
   764	

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