Re: [RFC v1 2/3] stacktrace, stackdepot: Add seprintf()-like variants of functions

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

Hi Alejandro,

[This is a private test report for your RFC patch.]
kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on akpm-mm/mm-nonmm-unstable linus/master v6.16-rc4 next-20250704]
[cannot apply to vbabka-slab/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Alejandro-Colomar/vsprintf-Add-v-seprintf-v-stprintf/20250706-043535
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/ec2e375c2d1ed006f23e31d2f6ec7b46a97ad71e.1751747518.git.alx%40kernel.org
patch subject: [RFC v1 2/3] stacktrace, stackdepot: Add seprintf()-like variants of functions
config: arm-randconfig-004-20250706 (https://download.01.org/0day-ci/archive/20250706/202507060829.EfvBsc49-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 14.3.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250706/202507060829.EfvBsc49-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/202507060829.EfvBsc49-lkp@intel.com/

All errors (new ones prefixed by >>):

   kernel/stacktrace.c: In function 'stack_trace_seprint':
   kernel/stacktrace.c:93:21: error: implicit declaration of function 'seprintf'; did you mean 'snprintf'? [-Wimplicit-function-declaration]
      93 |                 p = seprintf(p, end, "%*c%pS\n", 1 + spaces, ' ',
         |                     ^~~~~~~~
         |                     snprintf
>> kernel/stacktrace.c:93:19: error: assignment to 'char *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
      93 |                 p = seprintf(p, end, "%*c%pS\n", 1 + spaces, ' ',
         |                   ^


vim +93 kernel/stacktrace.c

    72	
    73	/**
    74	 * stack_trace_seprint - Print the entries in the stack trace into a buffer
    75	 * @p:		Pointer to the print buffer
    76	 * @end:	Pointer to one past the last element in the buffer
    77	 * @entries:	Pointer to storage array
    78	 * @nr_entries:	Number of entries in the storage array
    79	 * @spaces:	Number of leading spaces to print
    80	 *
    81	 * Return: Pointer to the trailing '\0'; or NULL on truncation.
    82	 */
    83	char *stack_trace_seprint(char *p, const char end[0],
    84				  const unsigned long *entries, unsigned int nr_entries,
    85				  int spaces)
    86	{
    87		unsigned int i;
    88	
    89		if (WARN_ON(!entries))
    90			return 0;
    91	
    92		for (i = 0; i < nr_entries; i++) {
  > 93			p = seprintf(p, end, "%*c%pS\n", 1 + spaces, ' ',
    94				     (void *)entries[i]);
    95		}
    96	
    97		return p;
    98	}
    99	EXPORT_SYMBOL_GPL(stack_trace_seprint);
   100	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki