[davidhildenbrand:folded_pgtable 13/13] ./include/asm-generic/pgtable-nop4d.h:46:43: error: implicit declaration of function 'pgd_val'; did you mean 'pgd_bad'?

[kernel test robot <lkp@intel.com>]

tree:   https://github.com/davidhildenbrand/linux folded_pgtable
head:   898b37f4865d94ff198bb62dfe2517a6d1b7d44e
commit: 898b37f4865d94ff198bb62dfe2517a6d1b7d44e [13/13] mm/pgtable: catch abuse of folded dummy pgd_t/p4d_t/pud_t
config: i386-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260704/202607040436.rwNEeGy7-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260704/202607040436.rwNEeGy7-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202607040436.rwNEeGy7-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from <command-line>:
   ./include/asm-generic/pgtable-nop4d.h: In function 'p4d_offset':
>> ./include/asm-generic/pgtable-nop4d.h:46:43: error: implicit declaration of function 'pgd_val'; did you mean 'pgd_bad'? [-Wimplicit-function-declaration]
      46 |         BUILD_BUG_ON(__builtin_constant_p(pgd_val(*pgd)));
         |                                           ^~~~~~~
   ././include/linux/compiler_types.h:682:23: note: in definition of macro '__compiletime_assert'
     682 |                 if (!(condition))                                       \
         |                       ^~~~~~~~~
   ././include/linux/compiler_types.h:702:9: note: in expansion of macro '_compiletime_assert'
     702 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   ./include/linux/build_bug.h:40:37: note: in expansion of macro 'compiletime_assert'
      40 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
         |                                     ^~~~~~~~~~~~~~~~~~
   ./include/linux/build_bug.h:51:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
      51 |         BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
         |         ^~~~~~~~~~~~~~~~
   ./include/asm-generic/pgtable-nop4d.h:46:9: note: in expansion of macro 'BUILD_BUG_ON'
      46 |         BUILD_BUG_ON(__builtin_constant_p(pgd_val(*pgd)));
         |         ^~~~~~~~~~~~


vim +46 ./include/asm-generic/pgtable-nop4d.h

    43	
    44	static __always_inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
    45	{
  > 46		BUILD_BUG_ON(__builtin_constant_p(pgd_val(*pgd)));
    47		return (p4d_t *)pgd;
    48	}
    49	

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