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Message-ID: <202512201303.je0bERQn-lkp@intel.com>
Date: Sat, 20 Dec 2025 13:03:31 +0100
From: kernel test robot <lkp@...el.com>
To: Vincent Mailhol <mailhol@...nel.org>,
Nathan Chancellor <nathan@...nel.org>,
Nicolas Schier <nsc@...nel.org>,
Nick Desaulniers <nick.desaulniers+lkml@...il.com>,
Bill Wendling <morbo@...gle.com>,
Justin Stitt <justinstitt@...gle.com>,
Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
Maxime Ripard <mripard@...nel.org>,
Thomas Zimmermann <tzimmermann@...e.de>,
David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
Chris Mason <chris.mason@...ionio.com>,
David Sterba <dsterba@...e.com>, Kees Cook <kees@...nel.org>,
"Gustavo A. R. Silva" <gustavoars@...nel.org>
Cc: oe-kbuild-all@...ts.linux.dev, linux-kbuild@...r.kernel.org,
linux-sparse@...r.kernel.org, linux-kernel@...r.kernel.org,
llvm@...ts.linux.dev, dri-devel@...ts.freedesktop.org,
linux-btrfs@...r.kernel.org, linux-hardening@...r.kernel.org,
Vincent Mailhol <mailhol@...nel.org>
Subject: Re: [PATCH v2 4/4] minmax: remove useless cast in __is_nonneg()
Hi Vincent,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 3e7f562e20ee87a25e104ef4fce557d39d62fa85]
url: https://github.com/intel-lab-lkp/linux/commits/Vincent-Mailhol/kbuild-remove-gcc-s-Wtype-limits/20251220-064204
base: 3e7f562e20ee87a25e104ef4fce557d39d62fa85
patch link: https://lore.kernel.org/r/20251219-remove_wtype-limits-v2-4-2e92b3f566c5%40kernel.org
patch subject: [PATCH v2 4/4] minmax: remove useless cast in __is_nonneg()
config: x86_64-rhel-9.4-ltp (https://download.01.org/0day-ci/archive/20251220/202512201303.je0bERQn-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/20251220/202512201303.je0bERQn-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@...el.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512201303.je0bERQn-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from <command-line>:
lib/lzo/lzo1x_compress.c: In function 'lzo1x_1_do_compress':
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:10: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:10: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:27: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:27: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
--
In file included from <command-line>:
lib/lzo/lzo1x_compress.c: In function 'lzo1x_1_do_compress_safe':
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:10: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:10: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:27: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
>> include/linux/minmax.h:65:46: warning: ordered comparison of pointer with integer zero [-Wextra]
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~
include/linux/compiler_types.h:610:23: note: in definition of macro '__compiletime_assert'
610 | if (!(condition)) \
| ^~~~~~~~~
include/linux/compiler_types.h:630:9: note: in expansion of macro '_compiletime_assert'
630 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:90:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:65:25: note: in expansion of macro 'statically_true'
65 | #define __is_nonneg(ux) statically_true((ux) >= 0)
| ^~~~~~~~~~~~~~~
include/linux/minmax.h:50:14: note: in expansion of macro '__is_nonneg'
50 | (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
| ^~~~~~~~~~~
include/linux/minmax.h:72:27: note: in expansion of macro '__sign_use'
72 | (__sign_use(ux) & __sign_use(uy))
| ^~~~~~~~~~
include/linux/minmax.h:90:27: note: in expansion of macro '__types_ok'
90 | BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
| ^~~~~~~~~~
include/linux/minmax.h:95:9: note: in expansion of macro '__careful_cmp_once'
95 | __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:102:25: note: in expansion of macro '__careful_cmp'
102 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
lib/lzo/lzo1x_compress.c:65:54: note: in expansion of macro 'min'
65 | const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
| ^~~
vim +65 include/linux/minmax.h
9
10 /*
11 * min()/max()/clamp() macros must accomplish several things:
12 *
13 * - Avoid multiple evaluations of the arguments (so side-effects like
14 * "x++" happen only once) when non-constant.
15 * - Perform signed v unsigned type-checking (to generate compile
16 * errors instead of nasty runtime surprises).
17 * - Unsigned char/short are always promoted to signed int and can be
18 * compared against signed or unsigned arguments.
19 * - Unsigned arguments can be compared against non-negative signed constants.
20 * - Comparison of a signed argument against an unsigned constant fails
21 * even if the constant is below __INT_MAX__ and could be cast to int.
22 */
23 #define __typecheck(x, y) \
24 (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
25
26 /*
27 * __sign_use for integer expressions:
28 * bit #0 set if ok for unsigned comparisons
29 * bit #1 set if ok for signed comparisons
30 *
31 * In particular, statically non-negative signed integer expressions
32 * are ok for both.
33 *
34 * NOTE! Unsigned types smaller than 'int' are implicitly converted to 'int'
35 * in expressions, and are accepted for signed conversions for now.
36 * This is debatable.
37 *
38 * Note that 'x' is the original expression, and 'ux' is the unique variable
39 * that contains the value.
40 *
41 * We use 'ux' for pure type checking, and 'x' for when we need to look at the
42 * value (but without evaluating it for side effects!
43 * Careful to only ever evaluate it with sizeof() or __builtin_constant_p() etc).
44 *
45 * Pointers end up being checked by the normal C type rules at the actual
46 * comparison, and these expressions only need to be careful to not cause
47 * warnings for pointer use.
48 */
49 #define __sign_use(ux) (is_signed_type(typeof(ux)) ? \
50 (2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
51
52 /*
53 * Check whether a signed value is always non-negative.
54 *
55 * On 64-bit any integer or pointer type can safely be cast to 'long long'.
56 * But on 32-bit we need to avoid warnings about casting pointers to integers
57 * of different sizes without truncating 64-bit values so 'long' or 'long long'
58 * must be used depending on the size of the value.
59 *
60 * This does not work for 128-bit signed integers since the cast would truncate
61 * them, but we do not use s128 types in the kernel (we do use 'u128',
62 * but they are handled by the !is_signed_type() case).
63 */
64 #if __SIZEOF_POINTER__ == __SIZEOF_LONG_LONG__
> 65 #define __is_nonneg(ux) statically_true((ux) >= 0)
66 #else
67 #define __is_nonneg(ux) statically_true( \
68 (typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, 1L)))(ux) >= 0)
69 #endif
70
--
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