[frank-w-bpi-r2-4.14:7.2-rc 220/220] drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:52:9: warning: incompatible implicit declaration of built-in function 'strncpy'

[frank-w-bpi-r2-4.14:7.2-rc 220/220] drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:52:9: warning: incompatible implicit declaration of built-in function 'strncpy'

[kernel test robot]

tree:   https://github.com/frank-w/BPI-R2-4.14 7.2-rc
head:   c29ccda7eca8bca9686ca69e284690c38ca9ed1c
commit: ba737cf5097bc593b8c8851be4d568aaa516bffb [220/220] net: phy: as21xxx: update driver to v1.9.2
config: i386-allmodconfig (https://download.01.org/0day-ci/archive/20260809/202608092301.Qm43JV8C-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/20260809/202608092301.Qm43JV8C-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/202608092301.Qm43JV8C-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c: In function 'parse_cmd_args':
   drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:52:9: error: implicit declaration of function 'strncpy' [-Wimplicit-function-declaration]
      52 |         strncpy(buffer, input, sizeof(buffer));
         |         ^~~~~~~
   drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:31:1: note: include '<string.h>' or provide a declaration of 'strncpy'
      30 | #include "as21xx_api.h"
     +++ |+#include <string.h>
      31 | #include <linux/timekeeping.h>
>> drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:52:9: warning: incompatible implicit declaration of built-in function 'strncpy' [-Wbuiltin-declaration-mismatch]
      52 |         strncpy(buffer, input, sizeof(buffer));
         |         ^~~~~~~
   drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c:52:9: note: include '<string.h>' or provide a declaration of 'strncpy'


vim +/strncpy +52 drivers/net/phy/as21xx_1.9.2/as21xx_bbu_api/as21xx_debugfs.c

    38	
    39	/******************************************************************************
    40	 * Static Function
    41	 *****************************************************************************/
    42	static int parse_cmd_args(const char *input, struct parsed_cmd *result, int max_args)
    43	{
    44		char buffer[MAX_BUF];
    45		char *token, *ptr;
    46		int count = 0;
    47		size_t len;
    48	
    49		if (!input || !result || max_args > MAX_ARGS)
    50			return -EINVAL;
    51	
  > 52		strncpy(buffer, input, sizeof(buffer));
    53		buffer[sizeof(buffer) - 1] = '\0';
    54	
    55		// clear '\n'
    56		len = strlen(buffer);
    57		if (len > 0 && buffer[len - 1] == '\n')
    58			buffer[len - 1] = '\0';
    59	
    60		ptr = buffer;
    61	
    62		token = strsep(&ptr, " ");
    63		while (token && *token == '\0')
    64			token = strsep(&ptr, " ");
    65	
    66		if (!token)
    67			return -EINVAL;
    68	
    69		strncpy(result->cmd, token, sizeof(result->cmd) - 1);
    70		result->cmd[sizeof(result->cmd) - 1] = '\0';
    71	
    72		while ((token = strsep(&ptr, " ")) != NULL && count < max_args) {
    73			if (*token == '\0')
    74				continue;
    75	
    76			if (kstrtol(token, 0, &result->args[count]) != 0)
    77				return -EINVAL;
    78	
    79			count++;
    80		}
    81	
    82		result->argc = count;
    83		return 0;
    84	}
    85	

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