[robh:dt/printf-modalias 1/1] lib/vsprintf.c:2230:4: warning: label followed by a declaration is a C23 extension

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

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git dt/printf-modalias
head:   57a93c86e542d479453f704d4911118c678bf31a
commit: 57a93c86e542d479453f704d4911118c678bf31a [1/1] of: Add printf '%pOFm' for generating modalias
config: arm64-randconfig-001-20241217 (https://download.01.org/0day-ci/archive/20241217/202412172352.WPdTcXgW-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 2dc22615fd46ab2566d0f26d5ba234ab12dc4bf8)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241217/202412172352.WPdTcXgW-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/202412172352.WPdTcXgW-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from lib/vsprintf.c:30:
   In file included from include/linux/kallsyms.h:13:
   In file included from include/linux/mm.h:2223:
   include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
     518 |         return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
         |                               ~~~~~~~~~~~ ^ ~~~
   In file included from lib/vsprintf.c:50:
   In file included from lib/../mm/internal.h:13:
   include/linux/mm_inline.h:47:41: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
      47 |         __mod_lruvec_state(lruvec, NR_LRU_BASE + lru, nr_pages);
         |                                    ~~~~~~~~~~~ ^ ~~~
   include/linux/mm_inline.h:49:22: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
      49 |                                 NR_ZONE_LRU_BASE + lru, nr_pages);
         |                                 ~~~~~~~~~~~~~~~~ ^ ~~~
>> lib/vsprintf.c:2230:4: warning: label followed by a declaration is a C23 extension [-Wc23-extensions]
    2230 |                         ssize_t len = of_modalias(dn, buf, end - buf);
         |                         ^
   4 warnings generated.


vim +2230 lib/vsprintf.c

  2146	
  2147	static noinline_for_stack
  2148	char *device_node_string(char *buf, char *end, struct device_node *dn,
  2149				 struct printf_spec spec, const char *fmt)
  2150	{
  2151		char tbuf[sizeof("xxxx") + 1];
  2152		const char *p;
  2153		int ret;
  2154		char *buf_start = buf;
  2155		struct property *prop;
  2156		bool has_mult, pass;
  2157	
  2158		struct printf_spec str_spec = spec;
  2159		str_spec.field_width = -1;
  2160	
  2161		if (fmt[0] != 'F')
  2162			return error_string(buf, end, "(%pO?)", spec);
  2163	
  2164		if (!IS_ENABLED(CONFIG_OF))
  2165			return error_string(buf, end, "(%pOF?)", spec);
  2166	
  2167		if (check_pointer(&buf, end, dn, spec))
  2168			return buf;
  2169	
  2170		/* simple case without anything any more format specifiers */
  2171		fmt++;
  2172		if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcCm") > 0)
  2173			fmt = "f";
  2174	
  2175		for (pass = false; strspn(fmt,"fnpPFcCm"); fmt++, pass = true) {
  2176			int precision;
  2177			if (pass) {
  2178				if (buf < end)
  2179					*buf = ':';
  2180				buf++;
  2181			}
  2182	
  2183			switch (*fmt) {
  2184			case 'f':	/* full_name */
  2185				buf = fwnode_full_name_string(of_fwnode_handle(dn), buf,
  2186							      end);
  2187				break;
  2188			case 'n':	/* name */
  2189				p = fwnode_get_name(of_fwnode_handle(dn));
  2190				precision = str_spec.precision;
  2191				str_spec.precision = strchrnul(p, '@') - p;
  2192				buf = string(buf, end, p, str_spec);
  2193				str_spec.precision = precision;
  2194				break;
  2195			case 'p':	/* phandle */
  2196				buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec);
  2197				break;
  2198			case 'P':	/* path-spec */
  2199				p = fwnode_get_name(of_fwnode_handle(dn));
  2200				if (!p[1])
  2201					p = "/";
  2202				buf = string(buf, end, p, str_spec);
  2203				break;
  2204			case 'F':	/* flags */
  2205				tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
  2206				tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
  2207				tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
  2208				tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
  2209				tbuf[4] = 0;
  2210				buf = string_nocheck(buf, end, tbuf, str_spec);
  2211				break;
  2212			case 'c':	/* major compatible string */
  2213				ret = of_property_read_string(dn, "compatible", &p);
  2214				if (!ret)
  2215					buf = string(buf, end, p, str_spec);
  2216				break;
  2217			case 'C':	/* full compatible string */
  2218				has_mult = false;
  2219				of_property_for_each_string(dn, "compatible", prop, p) {
  2220					if (has_mult)
  2221						buf = string_nocheck(buf, end, ",", str_spec);
  2222					buf = string_nocheck(buf, end, "\"", str_spec);
  2223					buf = string(buf, end, p, str_spec);
  2224					buf = string_nocheck(buf, end, "\"", str_spec);
  2225	
  2226					has_mult = true;
  2227				}
  2228				break;
  2229			case 'm':
> 2230				ssize_t len = of_modalias(dn, buf, end - buf);
  2231				if (len > 0)
  2232					buf += len;
  2233				break;
  2234			default:
  2235				break;
  2236			}
  2237		}
  2238	
  2239		return widen_string(buf, buf - buf_start, end, spec);
  2240	}
  2241	

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