Re: [PATCH v3 09/12] um: use nolibc for the --showconfig implementation

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

Hi Benjamin,

kernel test robot noticed the following build warnings:

[auto build test WARNING on uml/next]
[also build test WARNING on uml/fixes shuah-kselftest/next shuah-kselftest/fixes linus/master v6.17-rc7 next-20250925]
[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/Benjamin-Berg/tools-compiler-h-fix-__used-definition/20250924-222547
base:   https://git.kernel.org/pub/scm/linux/kernel/git/uml/linux next
patch link:    https://lore.kernel.org/r/20250924142059.527768-10-benjamin%40sipsolutions.net
patch subject: [PATCH v3 09/12] um: use nolibc for the --showconfig implementation
:::::: branch date: 2 days ago
:::::: commit date: 2 days ago
config: um-randconfig-r111-20250926 (https://download.01.org/0day-ci/archive/20250926/202509261452.g5peaXCc-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/20250926/202509261452.g5peaXCc-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/r/202509261452.g5peaXCc-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   command-line: note: in included file (through tools/include/nolibc/nolibc.h, tools/include/nolibc/stddef.h, arch/um/include/shared/user.h, builtin):
>> tools/include/nolibc/sys.h:109:29: sparse: sparse: Using plain integer as NULL pointer
   command-line: note: in included file (through tools/include/nolibc/nolibc.h, tools/include/nolibc/stddef.h, arch/um/include/shared/user.h, builtin):
>> tools/include/nolibc/sys/reboot.h:31:16: sparse: sparse: Using plain integer as NULL pointer
>> tools/include/nolibc/sys/reboot.h:31:16: sparse: sparse: Using plain integer as NULL pointer
   command-line: note: in included file (through tools/include/nolibc/nolibc.h, tools/include/nolibc/stddef.h, arch/um/include/shared/user.h, builtin):
>> tools/include/nolibc/unistd.h:57:27: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:57:30: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:57:33: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:70:27: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:70:30: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:70:33: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:81:30: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:81:33: sparse: sparse: Using plain integer as NULL pointer
   tools/include/nolibc/unistd.h:81:36: sparse: sparse: Using plain integer as NULL pointer
   command-line: note: in included file (through tools/include/nolibc/stdio.h, tools/include/nolibc/nolibc.h, tools/include/nolibc/stddef.h, ...):
   tools/include/nolibc/stdlib.h:56:6: sparse: sparse: symbol 'abort' redeclared with different type (different modifiers):
   tools/include/nolibc/stdlib.h:56:6: sparse:    void extern [addressable] [noreturn] [toplevel] [unused] abort( ... )
   tools/include/nolibc/stdlib.h:54:6: sparse: note: previously declared as:
   tools/include/nolibc/stdlib.h:54:6: sparse:    void extern [addressable] [toplevel] abort( ... )
   command-line: note: in included file (through tools/include/nolibc/nolibc.h, tools/include/nolibc/stddef.h, arch/um/include/shared/user.h, builtin):
   tools/include/nolibc/getopt.h:19:6: sparse: sparse: symbol 'optarg' was not declared. Should it be static?
   tools/include/nolibc/getopt.h:22:5: sparse: sparse: symbol 'optind' was not declared. Should it be static?
   tools/include/nolibc/getopt.h:22:17: sparse: sparse: symbol 'opterr' was not declared. Should it be static?
   tools/include/nolibc/getopt.h:22:29: sparse: sparse: symbol 'optopt' was not declared. Should it be static?
>> tools/include/nolibc/getopt.h:81:26: sparse: sparse: Using plain integer as NULL pointer

vim +109 tools/include/nolibc/sys.h

bd8c8fbb866fe5 Willy Tarreau 2022-02-07  104  
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  105  static __attribute__((unused))
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  106  void *sbrk(intptr_t inc)
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  107  {
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  108  	/* first call to find current end */
4201cfce15fe35 Zhangjin Wu   2023-07-07 @109  	void *ret = sys_brk(0);
4201cfce15fe35 Zhangjin Wu   2023-07-07  110  
4201cfce15fe35 Zhangjin Wu   2023-07-07  111  	if (ret && sys_brk(ret + inc) == ret + inc)
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  112  		return ret + inc;
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  113  
fb01ff635efd0a Willy Tarreau 2023-08-15  114  	SET_ERRNO(ENOMEM);
fb01ff635efd0a Willy Tarreau 2023-08-15  115  	return (void *)-1;
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  116  }
bd8c8fbb866fe5 Willy Tarreau 2022-02-07  117  

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