* [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min'
[not found] <53a3c359.yUYVC7fzjYpZLyLq%fengguang.wu@intel.com>
@ 2014-06-20 5:52 ` Fengguang Wu
2014-06-20 15:19 ` Michal Nazarewicz
0 siblings, 1 reply; 4+ messages in thread
From: Fengguang Wu @ 2014-06-20 5:52 UTC (permalink / raw)
To: Michal Nazarewicz
Cc: kbuild-all, Johannes Weiner, Hagen Paul Pfeifer, Andrew Morton,
Linux Memory Management List
tree: git://git.cmpxchg.org/linux-mmotm.git master
head: df25ba7db0775d87018e2cd92f26b9b087093840
commit: 99c369839f847d2cc4b8e759a9c57c925592efa2 [141/230] include/linux/kernel.h: rewrite min3, max3 and clamp using min and max
config: make ARCH=x86_64 allmodconfig
All warnings:
drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:25: sparse: incompatible types in comparison expression (different type sizes)
In file included from arch/x86/include/asm/percpu.h:44:0,
from arch/x86/include/asm/preempt.h:5,
from include/linux/preempt.h:18,
from include/linux/spinlock.h:50,
from include/linux/wait.h:8,
from include/linux/fs.h:6,
from drivers/net/ethernet/intel/i40e/i40e_debugfs.c:29:
drivers/net/ethernet/intel/i40e/i40e_debugfs.c: In function 'i40e_dbg_command_write':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
>> drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:11: note: in expansion of macro 'clamp'
bytes = clamp(bytes, (u16)1024, (u16)I40E_MAX_AQ_BUF_SIZE);
^
--
drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:269:21: sparse: incompatible types in comparison expression (different type sizes)
In file included from include/linux/sched.h:17:0,
from drivers/net/wireless/rtlwifi/rtl8723ae/../wifi.h:35,
from drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:31:
drivers/net/wireless/rtlwifi/rtl8723ae/dm.c: In function 'rtl92c_dm_ctrl_initgain_by_fa':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
>> drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:269:14: note: in expansion of macro 'clamp'
value_igi = clamp(value_igi, (u8)DM_DIG_FA_LOWER, (u8)DM_DIG_FA_UPPER);
^
--
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: expected unsigned int [unsigned] [usertype] d32
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: got restricted __be32 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: expected unsigned short [unsigned] dat
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: got restricted __be16 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: expected unsigned short [unsigned] [addressable] dat
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: got restricted __be16 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:437:23: sparse: incompatible types in comparison expression (different type sizes)
drivers/staging/iio/impedance-analyzer/ad5933.c:451:23: sparse: incompatible types in comparison expression (different type sizes)
In file included from include/linux/interrupt.h:5:0,
from drivers/staging/iio/impedance-analyzer/ad5933.c:9:
drivers/staging/iio/impedance-analyzer/ad5933.c: In function 'ad5933_store':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
>> drivers/staging/iio/impedance-analyzer/ad5933.c:437:9: note: in expansion of macro 'clamp'
val = clamp(val, (u16)0, (u16)0x7FF);
^
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
>> drivers/staging/iio/impedance-analyzer/ad5933.c:451:9: note: in expansion of macro 'clamp'
val = clamp(val, (u16)0, (u16)511);
^
sparse warnings: (new ones prefixed by >>)
>> drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:25: sparse: incompatible types in comparison expression (different type sizes)
In file included from arch/x86/include/asm/percpu.h:44:0,
from arch/x86/include/asm/preempt.h:5,
from include/linux/preempt.h:18,
from include/linux/spinlock.h:50,
from include/linux/wait.h:8,
from include/linux/fs.h:6,
from drivers/net/ethernet/intel/i40e/i40e_debugfs.c:29:
drivers/net/ethernet/intel/i40e/i40e_debugfs.c: In function 'i40e_dbg_command_write':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:11: note: in expansion of macro 'clamp'
bytes = clamp(bytes, (u16)1024, (u16)I40E_MAX_AQ_BUF_SIZE);
^
--
>> drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:269:21: sparse: incompatible types in comparison expression (different type sizes)
In file included from include/linux/sched.h:17:0,
from drivers/net/wireless/rtlwifi/rtl8723ae/../wifi.h:35,
from drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:31:
drivers/net/wireless/rtlwifi/rtl8723ae/dm.c: In function 'rtl92c_dm_ctrl_initgain_by_fa':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
drivers/net/wireless/rtlwifi/rtl8723ae/dm.c:269:14: note: in expansion of macro 'clamp'
value_igi = clamp(value_igi, (u8)DM_DIG_FA_LOWER, (u8)DM_DIG_FA_UPPER);
^
--
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: expected unsigned int [unsigned] [usertype] d32
drivers/staging/iio/impedance-analyzer/ad5933.c:241:17: got restricted __be32 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: expected unsigned short [unsigned] dat
drivers/staging/iio/impedance-analyzer/ad5933.c:263:13: got restricted __be16 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: sparse: incorrect type in assignment (different base types)
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: expected unsigned short [unsigned] [addressable] dat
drivers/staging/iio/impedance-analyzer/ad5933.c:271:13: got restricted __be16 [usertype] <noident>
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
drivers/staging/iio/impedance-analyzer/ad5933.c:310:19: sparse: cast to restricted __be32
>> drivers/staging/iio/impedance-analyzer/ad5933.c:437:23: sparse: incompatible types in comparison expression (different type sizes)
>> drivers/staging/iio/impedance-analyzer/ad5933.c:451:23: sparse: incompatible types in comparison expression (different type sizes)
In file included from include/linux/interrupt.h:5:0,
from drivers/staging/iio/impedance-analyzer/ad5933.c:9:
drivers/staging/iio/impedance-analyzer/ad5933.c: In function 'ad5933_store':
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
drivers/staging/iio/impedance-analyzer/ad5933.c:437:9: note: in expansion of macro 'clamp'
val = clamp(val, (u16)0, (u16)0x7FF);
^
include/linux/kernel.h:713:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
^
include/linux/kernel.h:744:28: note: in expansion of macro 'min'
#define clamp(val, lo, hi) min(max(val, lo), hi)
^
drivers/staging/iio/impedance-analyzer/ad5933.c:451:9: note: in expansion of macro 'clamp'
val = clamp(val, (u16)0, (u16)511);
^
vim +/min +744 include/linux/kernel.h
^1da177e Linus Torvalds 2005-04-16 707 * strict type-checking.. See the
^1da177e Linus Torvalds 2005-04-16 708 * "unnecessary" pointer comparison.
^1da177e Linus Torvalds 2005-04-16 709 */
bdf4bbaa Harvey Harrison 2008-04-30 710 #define min(x, y) ({ \
bdf4bbaa Harvey Harrison 2008-04-30 711 typeof(x) _min1 = (x); \
bdf4bbaa Harvey Harrison 2008-04-30 712 typeof(y) _min2 = (y); \
bdf4bbaa Harvey Harrison 2008-04-30 @713 (void) (&_min1 == &_min2); \
bdf4bbaa Harvey Harrison 2008-04-30 714 _min1 < _min2 ? _min1 : _min2; })
bdf4bbaa Harvey Harrison 2008-04-30 715
bdf4bbaa Harvey Harrison 2008-04-30 716 #define max(x, y) ({ \
bdf4bbaa Harvey Harrison 2008-04-30 717 typeof(x) _max1 = (x); \
bdf4bbaa Harvey Harrison 2008-04-30 718 typeof(y) _max2 = (y); \
bdf4bbaa Harvey Harrison 2008-04-30 719 (void) (&_max1 == &_max2); \
bdf4bbaa Harvey Harrison 2008-04-30 720 _max1 > _max2 ? _max1 : _max2; })
bdf4bbaa Harvey Harrison 2008-04-30 721
99c36983 Michal Nazarewicz 2014-06-20 722 #define min3(x, y, z) min(min(x, y), z)
99c36983 Michal Nazarewicz 2014-06-20 723 #define max3(x, y, z) max(max(x, y), z)
f27c85c5 Hagen Paul Pfeifer 2010-10-26 724
bdf4bbaa Harvey Harrison 2008-04-30 725 /**
c8bf1336 Martin K. Petersen 2010-09-10 726 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
c8bf1336 Martin K. Petersen 2010-09-10 727 * @x: value1
c8bf1336 Martin K. Petersen 2010-09-10 728 * @y: value2
c8bf1336 Martin K. Petersen 2010-09-10 729 */
c8bf1336 Martin K. Petersen 2010-09-10 730 #define min_not_zero(x, y) ({ \
c8bf1336 Martin K. Petersen 2010-09-10 731 typeof(x) __x = (x); \
c8bf1336 Martin K. Petersen 2010-09-10 732 typeof(y) __y = (y); \
c8bf1336 Martin K. Petersen 2010-09-10 733 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
c8bf1336 Martin K. Petersen 2010-09-10 734
c8bf1336 Martin K. Petersen 2010-09-10 735 /**
bdf4bbaa Harvey Harrison 2008-04-30 736 * clamp - return a value clamped to a given range with strict typechecking
bdf4bbaa Harvey Harrison 2008-04-30 737 * @val: current value
99c36983 Michal Nazarewicz 2014-06-20 738 * @lo: lowest allowable value
99c36983 Michal Nazarewicz 2014-06-20 739 * @hi: highest allowable value
bdf4bbaa Harvey Harrison 2008-04-30 740 *
bdf4bbaa Harvey Harrison 2008-04-30 741 * This macro does strict typechecking of min/max to make sure they are of the
bdf4bbaa Harvey Harrison 2008-04-30 742 * same type as val. See the unnecessary pointer comparisons.
bdf4bbaa Harvey Harrison 2008-04-30 743 */
99c36983 Michal Nazarewicz 2014-06-20 @744 #define clamp(val, lo, hi) min(max(val, lo), hi)
^1da177e Linus Torvalds 2005-04-16 745
^1da177e Linus Torvalds 2005-04-16 746 /*
^1da177e Linus Torvalds 2005-04-16 747 * ..and if you can't take the strict
---
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http://lists.01.org/mailman/listinfo/kbuild Intel Corporation
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min'
2014-06-20 5:52 ` [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min' Fengguang Wu
@ 2014-06-20 15:19 ` Michal Nazarewicz
2014-06-20 20:39 ` Andrew Morton
0 siblings, 1 reply; 4+ messages in thread
From: Michal Nazarewicz @ 2014-06-20 15:19 UTC (permalink / raw)
To: Fengguang Wu
Cc: kbuild-all, Johannes Weiner, Hagen Paul Pfeifer, Andrew Morton,
Linux Memory Management List
On Fri, Jun 20 2014, Fengguang Wu <fengguang.wu@intel.com> wrote:
>>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
> #define clamp(val, lo, hi) min(max(val, lo), hi)
> ^
>>> drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:11: note: in expansion of macro 'clamp'
> bytes = clamp(bytes, (u16)1024, (u16)I40E_MAX_AQ_BUF_SIZE);
> ^
The obvious fix:
----------- >8 --------------------------------------------------------------
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 44649e0..149864b 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -719,8 +719,8 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
(void) (&_max1 == &_max2); \
_max1 > _max2 ? _max1 : _max2; })
-#define min3(x, y, z) min(min(x, y), z)
-#define max3(x, y, z) max(max(x, y), z)
+#define min3(x, y, z) min((typeof(x))min(x, y), z)
+#define max3(x, y, z) max((typeof(x))max(x, y), z)
/**
* min_not_zero - return the minimum that is _not_ zero, unless both are zero
@@ -741,7 +741,7 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
* This macro does strict typechecking of min/max to make sure they are of the
* same type as val. See the unnecessary pointer comparisons.
*/
-#define clamp(val, lo, hi) min(max(val, lo), hi)
+#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
/*
* ..and if you can't take the strict
----------- >8 --------------------------------------------------------------
increases size of the kernel:
-rwx------ 1 mpn eng 437026785 Jun 20 15:45 vmlinux.before
-rwx------ 1 mpn eng 437026881 Jun 20 15:30 vmlinux.after
even though it's still slightly smaller than w/o the patch all together:
-rwx------ 1 mpn eng 437027411 Jun 20 16:04 vmlinux.before.before
--
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o
..o | Computer Science, Michał “mina86” Nazarewicz (o o)
ooo +--<mpn@google.com>--<xmpp:mina86@jabber.org>--ooO--(_)--Ooo--
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^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min'
2014-06-20 15:19 ` Michal Nazarewicz
@ 2014-06-20 20:39 ` Andrew Morton
2014-06-20 21:16 ` Michal Nazarewicz
0 siblings, 1 reply; 4+ messages in thread
From: Andrew Morton @ 2014-06-20 20:39 UTC (permalink / raw)
To: Michal Nazarewicz
Cc: Fengguang Wu, kbuild-all, Johannes Weiner, Hagen Paul Pfeifer,
Linux Memory Management List
On Fri, 20 Jun 2014 17:19:55 +0200 Michal Nazarewicz <mina86@mina86.com> wrote:
> On Fri, Jun 20 2014, Fengguang Wu <fengguang.wu@intel.com> wrote:
> >>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
> > #define clamp(val, lo, hi) min(max(val, lo), hi)
> > ^
> >>> drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:11: note: in expansion of macro 'clamp'
> > bytes = clamp(bytes, (u16)1024, (u16)I40E_MAX_AQ_BUF_SIZE);
> > ^
>
> The obvious fix:
>
> ----------- >8 --------------------------------------------------------------
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 44649e0..149864b 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -719,8 +719,8 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
> (void) (&_max1 == &_max2); \
> _max1 > _max2 ? _max1 : _max2; })
>
> -#define min3(x, y, z) min(min(x, y), z)
> -#define max3(x, y, z) max(max(x, y), z)
> +#define min3(x, y, z) min((typeof(x))min(x, y), z)
> +#define max3(x, y, z) max((typeof(x))max(x, y), z)
I don't get it. All the types are u16 so we should be good.
What is the return type of
_max1 > _max2 ? _max1 : _max2;
when both _max1 and _max2 are u16? Something other than u16 apparently
- I never knew that.
Maybe we should be fixing min() and max()?
--- a/include/linux/kernel.h~a
+++ a/include/linux/kernel.h
@@ -711,13 +711,13 @@ static inline void ftrace_dump(enum ftra
typeof(x) _min1 = (x); \
typeof(y) _min2 = (y); \
(void) (&_min1 == &_min2); \
- _min1 < _min2 ? _min1 : _min2; })
+ (typeof(x))(_min1 < _min2 ? _min1 : _min2); })
#define max(x, y) ({ \
typeof(x) _max1 = (x); \
typeof(y) _max2 = (y); \
(void) (&_max1 == &_max2); \
- _max1 > _max2 ? _max1 : _max2; })
+ (typeof(x))(_max1 > _max2 ? _max1 : _max2); })
#define min3(x, y, z) min(min(x, y), z)
#define max3(x, y, z) max(max(x, y), z)
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min'
2014-06-20 20:39 ` Andrew Morton
@ 2014-06-20 21:16 ` Michal Nazarewicz
0 siblings, 0 replies; 4+ messages in thread
From: Michal Nazarewicz @ 2014-06-20 21:16 UTC (permalink / raw)
To: Andrew Morton
Cc: Fengguang Wu, kbuild-all, Johannes Weiner, Hagen Paul Pfeifer,
Linux Memory Management List
On Fri, Jun 20 2014, Andrew Morton <akpm@linux-foundation.org> wrote:
> On Fri, 20 Jun 2014 17:19:55 +0200 Michal Nazarewicz <mina86@mina86.com> wrote:
>
>> On Fri, Jun 20 2014, Fengguang Wu <fengguang.wu@intel.com> wrote:
>> >>> include/linux/kernel.h:744:28: note: in expansion of macro 'min'
>> > #define clamp(val, lo, hi) min(max(val, lo), hi)
>> > ^
>> >>> drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1901:11: note: in expansion of macro 'clamp'
>> > bytes = clamp(bytes, (u16)1024, (u16)I40E_MAX_AQ_BUF_SIZE);
>> > ^
>>
>> The obvious fix:
>>
>> ----------- >8 --------------------------------------------------------------
>> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
>> index 44649e0..149864b 100644
>> --- a/include/linux/kernel.h
>> +++ b/include/linux/kernel.h
>> @@ -719,8 +719,8 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
>> (void) (&_max1 == &_max2); \
>> _max1 > _max2 ? _max1 : _max2; })
>>
>> -#define min3(x, y, z) min(min(x, y), z)
>> -#define max3(x, y, z) max(max(x, y), z)
>> +#define min3(x, y, z) min((typeof(x))min(x, y), z)
>> +#define max3(x, y, z) max((typeof(x))max(x, y), z)
>
> I don't get it. All the types are u16 so we should be good.
>
> What is the return type of
>
> _max1 > _max2 ? _max1 : _max2;
int… Since C promotes it. (Or unsigned, I never remember, but I think
int if the possible values fit in signed int).
> when both _max1 and _max2 are u16? Something other than u16 apparently
> - I never knew that.
>
> Maybe we should be fixing min() and max()?
This is also an option. It would make min() and max() behave more like
a function which takes arguments of type T and returns value of type T.
Currently it behaves as a C operation which undergoes all the promotion
rules other arithmetic operations undergo (i.e. all types smaller than
int get promoted to int). I don't have opinion either way.
> --- a/include/linux/kernel.h~a
> +++ a/include/linux/kernel.h
> @@ -711,13 +711,13 @@ static inline void ftrace_dump(enum ftra
> typeof(x) _min1 = (x); \
> typeof(y) _min2 = (y); \
> (void) (&_min1 == &_min2); \
> - _min1 < _min2 ? _min1 : _min2; })
> + (typeof(x))(_min1 < _min2 ? _min1 : _min2); })
>
> #define max(x, y) ({ \
> typeof(x) _max1 = (x); \
> typeof(y) _max2 = (y); \
> (void) (&_max1 == &_max2); \
> - _max1 > _max2 ? _max1 : _max2; })
> + (typeof(x))(_max1 > _max2 ? _max1 : _max2); })
>
> #define min3(x, y, z) min(min(x, y), z)
> #define max3(x, y, z) max(max(x, y), z)
>
--
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o
..o | Computer Science, Michał “mina86” Nazarewicz (o o)
ooo +--<mpn@google.com>--<xmpp:mina86@jabber.org>--ooO--(_)--Ooo--
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[not found] <53a3c359.yUYVC7fzjYpZLyLq%fengguang.wu@intel.com>
2014-06-20 5:52 ` [mmotm:master 141/230] include/linux/kernel.h:744:28: note: in expansion of macro 'min' Fengguang Wu
2014-06-20 15:19 ` Michal Nazarewicz
2014-06-20 20:39 ` Andrew Morton
2014-06-20 21:16 ` Michal Nazarewicz
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