Convert constants between 0 and INT_MAX to 'int' prior to comparisons
so that min(signed_var, 20u) and, more commonly, min(signed_var, sizeof())
are both valid.
Signed-off-by: David Laight <david.laight@aculab.com>
---
v2: Add cast to fix min/max with pointer types.
include/linux/minmax.h | 34 ++++++++++++++++++++++------------
1 file changed, 22 insertions(+), 12 deletions(-)
diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 7d3ad9cbbff6..28edafb3dcca 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -8,20 +8,30 @@
/*
* min()/max()/clamp() macros must accomplish three things:
*
- * - avoid multiple evaluations of the arguments (so side-effects like
+ * - Avoid multiple evaluations of the arguments (so side-effects like
* "x++" happen only once) when non-constant.
- * - perform signed v unsigned type-checking (to generate compile
+ * - Perform signed v unsigned type-checking (to generate compile
* errors instead of nasty runtime surprises).
- * - retain result as a constant expressions when called with only
+ * Constants from 0 to INT_MAX are cast to (int) so can be used
+ * in comparisons with signed types.
+ * - Retain result as a constant expressions when called with only
* constant expressions (to avoid tripping VLA warnings in stack
* allocation usage).
*/
#define __typecheck(x, y) \
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
-#define __types_ok(x, y) \
- (is_signed_type(typeof(x)) == is_signed_type(typeof(y)) || \
- is_signed_type(typeof((x) + 0)) == is_signed_type(typeof((y) + 0)))
+#define __is_noneg_int(x) \
+ __builtin_choose_expr(!__is_constexpr(x), false, \
+ ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
+
+#define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
+
+#define __is_signed(x) is_signed_type(typeof(x))
+#define __types_ok(x, y) \
+ (__is_signed(x) == __is_signed(y) || \
+ __is_signed((x) + 0) == __is_signed((y) + 0) || \
+ __is_noneg_int(x) || __is_noneg_int(y))
#define __cmp_op_min <
#define __cmp_op_max >
@@ -29,24 +39,24 @@
#define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
#define __cmp_once(op, x, y, unique_x, unique_y) ({ \
- typeof(x) unique_x = (x); \
- typeof(y) unique_y = (y); \
+ typeof(__int_const(x)) unique_x = (x); \
+ typeof(__int_const(y)) unique_y = (y); \
static_assert(__types_ok(x, y), \
#op "(" #x ", " #y ") signedness error, fix types or consider " #op "_unsigned() before " #op "_t()"); \
__cmp(op, unique_x, unique_y); })
#define __careful_cmp(op, x, y) \
__builtin_choose_expr(__is_constexpr((x) - (y)), \
- __cmp(op, x, y), \
+ __cmp(op, __int_const(x), __int_const(y)), \
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
#define __clamp(val, lo, hi) \
((val) >= (hi) ? (hi) : ((val) <= (lo) ? (lo) : (val)))
#define __clamp_once(val, lo, hi, unique_val, unique_lo, unique_hi) ({ \
- typeof(val) unique_val = (val); \
- typeof(lo) unique_lo = (lo); \
- typeof(hi) unique_hi = (hi); \
+ typeof(__int_const(val)) unique_val = (val); \
+ typeof(__int_const(lo)) unique_lo = (lo); \
+ typeof(__int_const(hi)) unique_hi = (hi); \
static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)), \
(lo) <= (hi), true), \
"clamp() low limit " #lo " greater than high limit " #hi); \
--
2.17.1
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)By the time I've done:
#define __is_noneg_int(x) \
__builtin_choose_expr(!__is_constexpr(x), false, \
((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
#define __is_signed(x) \
__builtin_choose_expr(__is_constexpr(is_signed_type(typeof(x))), \
is_signed_type(typeof(x)), 0)
#define __types_ok(x, y) \
(__is_signed(x) == __is_signed(y) || \
__is_signed((x) + 0) == __is_signed((y) + 0) || \
__is_noneg_int(x) || __is_noneg_int(y))
the error message for
> static_assert(__types_ok(x, y), \
> #op "(" #x ", " #y ") signedness error, fix types or consider " #op "_unsigned() before " #op "_t()"); \
generated by clang 8.0.0 and later is similar to (see https://godbolt.org/z/jq613Gnsa):
<source>:49:12: error: static assertion failed due to requirement '__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0) == __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0) || __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0) == __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0) || (__builtin_choose_expr(!(sizeof(int) == sizeof (*(8 ? ((void *)((long)(a) * 0L)) : (int *)8))), 0, __builtin_choose_expr(__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0), a, 0) >= 0 && (a) <= (int)(long)2147483647)) || (__builtin_choose_expr(!(sizeof(int) == sizeof (*(8 ? ((void *)((long)(2147483648U - 0) * 0L)) : (int *)8))), 0, __builtin_choose_expr(__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0), 2147483648U - 0, 0) >= 0 && (2147483648U - 0) <= (unsigned int)(long)2147483647))': min(a, 0x80000000u - 0) signedness error, fix types or consider min_unsigned() before min_t()
Repeating the expression seems somewhat sub-optimal!
Surely it shouldn't be outputting the expansion of the
input when an error message is supplied?
Is there any (sane) way to stop it being that verbose?
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
On Mon, Jul 31, 2023 at 6:27 AM David Laight <David.Laight@aculab.com> wrote:
>
> By the time I've done:
>
> #define __is_noneg_int(x) \
> __builtin_choose_expr(!__is_constexpr(x), false, \
> ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
>
> #define __is_signed(x) \
> __builtin_choose_expr(__is_constexpr(is_signed_type(typeof(x))), \
> is_signed_type(typeof(x)), 0)
>
> #define __types_ok(x, y) \
> (__is_signed(x) == __is_signed(y) || \
> __is_signed((x) + 0) == __is_signed((y) + 0) || \
> __is_noneg_int(x) || __is_noneg_int(y))
>
> the error message for
>
> > static_assert(__types_ok(x, y), \
> > #op "(" #x ", " #y ") signedness error, fix types or consider " #op "_unsigned() before " #op "_t()"); \
>
> generated by clang 8.0.0 and later is similar to (see https://godbolt.org/z/jq613Gnsa):
>
> <source>:49:12: error: static assertion failed due to requirement '__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0) == __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0) || __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0) == __builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0) || (__builtin_choose_expr(!(sizeof(int) == sizeof (*(8 ? ((void *)((long)(a) * 0L)) : (int *)8))), 0, __builtin_choose_expr(__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((int)(-1)) < (int)1)) * 0L)) : (int *)8))), (((int)(-1)) < (int)1), 0), a, 0) >= 0 && (a) <= (int)(long)2147483647)) || (__builtin_choose_expr(!(sizeof(int) == sizeof (*(8 ? ((void *)((long)(2147483648U - 0) * 0L)) : (int *)8))), 0, __builtin_choose_expr(__builtin_choose_expr((sizeof(int) == sizeof (*(8 ? ((void *)((long)((((unsigned int)(-1)) < (unsigned int)1)) * 0L)) : (int *)8))), (((unsigned int)(-1)) < (unsigned int)1), 0), 2147483648U - 0, 0) >= 0 && (2147483648U - 0) <= (unsigned int)(long)2147483647))': min(a, 0x80000000u - 0) signedness error, fix types or consider min_unsigned() before min_t()
>
> Repeating the expression seems somewhat sub-optimal!
> Surely it shouldn't be outputting the expansion of the
> input when an error message is supplied?
>
> Is there any (sane) way to stop it being that verbose?
No, but we can probably change that in clang. Filed:
https://github.com/llvm/llvm-project/issues/64310
>
> David
>
> -
> Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
> Registration No: 1397386 (Wales)
--
Thanks,
~Nick Desaulniers
Hi David,
kernel test robot noticed the following build warnings:
[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master crng-random/master v6.5-rc3 next-20230728]
[cannot apply to next-20230728]
[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/David-Laight/minmax-Add-min_unsigned-a-b-and-max_unsigned-a-b/20230728-225439
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/b4ce9dad748e489f9314a2dc95615033%40AcuMS.aculab.com
patch subject: [PATCH next v2 5/5] minmax: Relax check to allow comparison between int and small unsigned constants.
config: alpha-randconfig-r024-20230727 (https://download.01.org/0day-ci/archive/20230729/202307290538.EtRKfGgC-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230729/202307290538.EtRKfGgC-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/202307290538.EtRKfGgC-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from include/linux/kernel.h:27,
from include/linux/cpumask.h:10,
from include/linux/mm_types_task.h:14,
from include/linux/mm_types.h:5,
from include/linux/buildid.h:5,
from include/linux/module.h:14,
from net/ceph/osdmap.c:5:
net/ceph/osdmap.c: In function 'osdmap_decode':
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:27: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:45: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:51: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:57: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:42:16: note: in expansion of macro '__int_const'
42 | typeof(__int_const(x)) unique_x = (x); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:43:16: note: in expansion of macro '__int_const'
43 | typeof(__int_const(y)) unique_y = (y); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
In file included from include/linux/container_of.h:5,
from include/linux/list.h:5,
from include/linux/module.h:12:
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:17: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:38: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:1773:54: note: in expansion of macro 'min'
1773 | err = osdmap_set_crush(map, crush_decode(*p, min(*p + len, end)));
| ^~~
net/ceph/osdmap.c: In function 'osdmap_apply_incremental':
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:27: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:45: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:51: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:57: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:42:16: note: in expansion of macro '__int_const'
42 | typeof(__int_const(x)) unique_x = (x); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:43:16: note: in expansion of macro '__int_const'
43 | typeof(__int_const(y)) unique_y = (y); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:17: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:38: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2000:46: note: in expansion of macro 'min'
2000 | return ceph_osdmap_decode(p, min(*p+len, end), msgr2);
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:27: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:45: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:51: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:27: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
>> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:39:57: note: in definition of macro '__cmp'
39 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
| ^
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:50:43: note: in expansion of macro '__int_const'
50 | __cmp(op, __int_const(x), __int_const(y)), \
| ^~~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:42:16: note: in expansion of macro '__int_const'
42 | typeof(__int_const(x)) unique_x = (x); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/minmax.h:28:47: note: in expansion of macro '__is_noneg_int'
28 | #define __int_const(x) __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:43:16: note: in expansion of macro '__int_const'
43 | typeof(__int_const(y)) unique_y = (y); \
| ^~~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:17: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
| ^~~
include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra]
26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/minmax.h:44:9: note: in expansion of macro 'static_assert'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~~~~
include/linux/minmax.h:34:38: note: in expansion of macro '__is_noneg_int'
34 | __is_noneg_int(x) || __is_noneg_int(y))
| ^~~~~~~~~~~~~~
include/linux/minmax.h:44:23: note: in expansion of macro '__types_ok'
44 | static_assert(__types_ok(x, y), \
| ^~~~~~~~~~
include/linux/minmax.h:51:17: note: in expansion of macro '__cmp_once'
51 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
| ^~~~~~~~~~
include/linux/minmax.h:78:25: note: in expansion of macro '__careful_cmp'
78 | #define min(x, y) __careful_cmp(min, x, y)
| ^~~~~~~~~~~~~
net/ceph/osdmap.c:2007:57: note: in expansion of macro 'min'
2007 | crush_decode(*p, min(*p + len, end)));
..
vim +26 include/linux/minmax.h
7
8 /*
9 * min()/max()/clamp() macros must accomplish three things:
10 *
11 * - Avoid multiple evaluations of the arguments (so side-effects like
12 * "x++" happen only once) when non-constant.
13 * - Perform signed v unsigned type-checking (to generate compile
14 * errors instead of nasty runtime surprises).
15 * Constants from 0 to INT_MAX are cast to (int) so can be used
16 * in comparisons with signed types.
17 * - Retain result as a constant expressions when called with only
18 * constant expressions (to avoid tripping VLA warnings in stack
19 * allocation usage).
20 */
21 #define __typecheck(x, y) \
22 (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
23
24 #define __is_noneg_int(x) \
25 __builtin_choose_expr(!__is_constexpr(x), false, \
> 26 ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
27
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
From: kernel test robot > Sent: 28 July 2023 22:43 > > kernel test robot noticed the following build warnings: > > [auto build test WARNING on akpm-mm/mm-everything] > [also build test WARNING on linus/master crng-random/master v6.5-rc3 next-20230728] > [cannot apply to next-20230728] > [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/David-Laight/minmax-Add-min_unsigned-a-b-and- > max_unsigned-a-b/20230728-225439 > base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything > patch link: https://lore.kernel.org/r/b4ce9dad748e489f9314a2dc95615033%40AcuMS.aculab.com > patch subject: [PATCH next v2 5/5] minmax: Relax check to allow comparison between int and small > unsigned constants. > config: alpha-randconfig-r024-20230727 (https://download.01.org/0day- > ci/archive/20230729/202307290538.EtRKfGgC-lkp@intel.com/config) > compiler: alpha-linux-gcc (GCC) 12.3.0 > reproduce: (https://download.01.org/0day-ci/archive/20230729/202307290538.EtRKfGgC- > 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/202307290538.EtRKfGgC-lkp@intel.com/ > > All warnings (new ones prefixed by >>): > > In file included from include/linux/kernel.h:27, > from include/linux/cpumask.h:10, > from include/linux/mm_types_task.h:14, > from include/linux/mm_types.h:5, > from include/linux/buildid.h:5, > from include/linux/module.h:14, > from net/ceph/osdmap.c:5: > net/ceph/osdmap.c: In function 'osdmap_decode': > >> include/linux/minmax.h:26:22: warning: ordered comparison of pointer with null pointer [-Wextra] > 26 | ((x) >= (typeof(x))0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__)) I have a cunning plan to fix this (and warnings about testing 'unsigned >= 0'). Basically replace the first test with: __builtin_choose_expr(is_signed(x), x, 1) >= 0 (Also fixes the build with clang < 16.) Hopefully that v3 will keep the build robert happy :-) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
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