tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   30185b69a2d533c4ba6ca926b8390ce7de495e29
commit: 295bcca84916cb5079140a89fccb472bb8d1f6e2 linux/bits.h: add compile time sanity check of GENMASK inputs
date:   4 months ago
config: s390-randconfig-r001-20200808 (attached as .config)
compiler: s390-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
        git checkout 295bcca84916cb5079140a89fccb472bb8d1f6e2
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390 

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 >>):

   drivers/mux/mmio.c: In function 'mux_mmio_probe':
   drivers/mux/mmio.c:76:20: error: storage size of 'field' isn't known
      76 |   struct reg_field field;
         |                    ^~~~~
   In file included from include/linux/bits.h:23,
                    from include/linux/bitops.h:5,
                    from drivers/mux/mmio.c:8:
>> include/linux/bits.h:25:21: error: first argument to '__builtin_choose_expr' not a constant
      25 |  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
         |                     ^~~~~~~~~~~~~~~~~~~~~
   include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
      16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
         |                                                              ^
   include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
      39 |  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
         |   ^~~~~~~~~~~~~~~~~~~
   drivers/mux/mmio.c:96:15: note: in expansion of macro 'GENMASK'
      96 |   if (mask != GENMASK(field.msb, field.lsb)) {
         |               ^~~~~~~
   include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant
      16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
         |                                                   ^
   include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
      25 |  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
         |   ^~~~~~~~~~~~~~~~~
   include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
      39 |  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
         |   ^~~~~~~~~~~~~~~~~~~
   drivers/mux/mmio.c:96:15: note: in expansion of macro 'GENMASK'
      96 |   if (mask != GENMASK(field.msb, field.lsb)) {
         |               ^~~~~~~
   drivers/mux/mmio.c:102:15: error: implicit declaration of function 'devm_regmap_field_alloc' [-Werror=implicit-function-declaration]
     102 |   fields[i] = devm_regmap_field_alloc(dev, regmap, field);
         |               ^~~~~~~~~~~~~~~~~~~~~~~
   drivers/mux/mmio.c:76:20: warning: unused variable 'field' [-Wunused-variable]
      76 |   struct reg_field field;
         |                    ^~~~~
   cc1: some warnings being treated as errors

vim +/__builtin_choose_expr +25 include/linux/bits.h

    15	
    16	/*
    17	 * Create a contiguous bitmask starting at bit position @l and ending at
    18	 * position @h. For example
    19	 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
    20	 */
    21	#if !defined(__ASSEMBLY__) && \
    22		(!defined(CONFIG_CC_IS_GCC) || CONFIG_GCC_VERSION >= 49000)
  > 23	#include <linux/build_bug.h>
    24	#define GENMASK_INPUT_CHECK(h, l) \
  > 25		(BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
    26			__builtin_constant_p((l) > (h)), (l) > (h), 0)))
    27	#else
    28	/*
    29	 * BUILD_BUG_ON_ZERO is not available in h files included from asm files,
    30	 * disable the input check if that is the case.
    31	 */
    32	#define GENMASK_INPUT_CHECK(h, l) 0
    33	#endif
    34	

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