Re: [PATCH] err.h: allow IS_ERR_VALUE to handle properly more types

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

[-- Attachment #1: Type: text/plain, Size: 5166 bytes --]

Hi Andrzej,

[auto build test WARNING on v4.4-rc8]
[also build test WARNING on next-20160107]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url:    https://github.com/0day-ci/linux/commits/Andrzej-Hajda/err-h-allow-IS_ERR_VALUE-to-handle-properly-more-types/20160107-230216
config: i386-allmodconfig (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All warnings (new ones prefixed by >>):

   In file included from arch/x86/include/asm/processor.h:31:0,
                    from arch/x86/include/asm/thread_info.h:52,
                    from include/linux/thread_info.h:54,
                    from arch/x86/include/asm/preempt.h:6,
                    from include/linux/preempt.h:59,
                    from include/linux/spinlock.h:50,
                    from drivers/staging/rtl8723au/include/osdep_service.h:22,
                    from drivers/staging/rtl8723au/include/rtl8723a_sreset.h:18,
                    from drivers/staging/rtl8723au/hal/rtl8723a_sreset.c:17:
   include/linux/err.h: In function 'IS_ERR':
>> include/linux/err.h:21:42: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
    #define IS_ERR_VALUE(x) ((typeof(x))(-1) < 0 \
                                             ^
>> include/linux/err.h:37:9: note: in expansion of macro 'IS_ERR_VALUE'
     return IS_ERR_VALUE((unsigned long)ptr);
            ^
   In file included from include/linux/linkage.h:4:0,
                    from include/linux/preempt.h:9,
                    from include/linux/spinlock.h:50,
                    from drivers/staging/rtl8723au/include/osdep_service.h:22,
                    from drivers/staging/rtl8723au/include/rtl8723a_sreset.h:18,
                    from drivers/staging/rtl8723au/hal/rtl8723a_sreset.c:17:
   include/linux/err.h:22:20: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
        ? unlikely((x) < 0) \
                       ^
   include/linux/compiler.h:166:42: note: in definition of macro 'unlikely'
    # define unlikely(x) __builtin_expect(!!(x), 0)
                                             ^
>> include/linux/err.h:37:9: note: in expansion of macro 'IS_ERR_VALUE'
     return IS_ERR_VALUE((unsigned long)ptr);
            ^
   In file included from arch/x86/include/asm/processor.h:31:0,
                    from arch/x86/include/asm/thread_info.h:52,
                    from include/linux/thread_info.h:54,
                    from arch/x86/include/asm/preempt.h:6,
                    from include/linux/preempt.h:59,
                    from include/linux/spinlock.h:50,
                    from drivers/staging/rtl8723au/include/osdep_service.h:22,
                    from drivers/staging/rtl8723au/include/rtl8723a_sreset.h:18,
                    from drivers/staging/rtl8723au/hal/rtl8723a_sreset.c:17:
   include/linux/err.h: In function 'IS_ERR_OR_NULL':
>> include/linux/err.h:21:42: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
    #define IS_ERR_VALUE(x) ((typeof(x))(-1) < 0 \
                                             ^
   include/linux/err.h:42:17: note: in expansion of macro 'IS_ERR_VALUE'
     return !ptr || IS_ERR_VALUE((unsigned long)ptr);
                    ^
   In file included from include/linux/linkage.h:4:0,
                    from include/linux/preempt.h:9,
                    from include/linux/spinlock.h:50,
                    from drivers/staging/rtl8723au/include/osdep_service.h:22,
                    from drivers/staging/rtl8723au/include/rtl8723a_sreset.h:18,
                    from drivers/staging/rtl8723au/hal/rtl8723a_sreset.c:17:
   include/linux/err.h:22:20: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
        ? unlikely((x) < 0) \
                       ^
   include/linux/compiler.h:166:42: note: in definition of macro 'unlikely'
    # define unlikely(x) __builtin_expect(!!(x), 0)
                                             ^
   include/linux/err.h:42:17: note: in expansion of macro 'IS_ERR_VALUE'
     return !ptr || IS_ERR_VALUE((unsigned long)ptr);
                    ^

vim +21 include/linux/err.h

    15	 * error and pointer decisions.
    16	 */
    17	#define MAX_ERRNO	4095
    18	
    19	#ifndef __ASSEMBLY__
    20	
  > 21	#define IS_ERR_VALUE(x) ((typeof(x))(-1) < 0 \
    22					? unlikely((x) < 0) \
    23					: unlikely((x) >= (typeof(x))-MAX_ERRNO))
    24	
    25	static inline void * __must_check ERR_PTR(long error)
    26	{
    27		return (void *) error;
    28	}
    29	
    30	static inline long __must_check PTR_ERR(__force const void *ptr)
    31	{
    32		return (long) ptr;
    33	}
    34	
    35	static inline bool __must_check IS_ERR(__force const void *ptr)
    36	{
  > 37		return IS_ERR_VALUE((unsigned long)ptr);
    38	}
    39	
    40	static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 52542 bytes --]