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From:   David Laight <David.Laight@ACULAB.COM>
To:     "'linux-kernel@vger.kernel.org'" <linux-kernel@vger.kernel.org>,
        "'Andy Shevchenko'" <andriy.shevchenko@linux.intel.com>,
        'Andrew Morton' <akpm@linux-foundation.org>,
        "'Matthew Wilcox (Oracle)'" <willy@infradead.org>,
        'Christoph Hellwig' <hch@infradead.org>,
        "'Jason A. Donenfeld'" <Jason@zx2c4.com>,
        'Linus Torvalds' <torvalds@linux-foundation.org>
Subject: [PATCH v3 4/5] minmax: Allow comparisons of 'int' against 'unsigned
 char/short'.
Thread-Topic: [PATCH v3 4/5] minmax: Allow comparisons of 'int' against
 'unsigned char/short'.
Thread-Index: AdnGwjJw1R+iwy+yQTyatTq077Viag==
Date:   Fri, 4 Aug 2023 10:55:39 +0000
Message-ID: <423c552b375c46ddab16488d33dee528@AcuMS.aculab.com>
References: <01e3e09005e9434b8f558a893a47c053@AcuMS.aculab.com>
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Since 'unsigned char/short' get promoted to 'signed int' it is
safe to compare them against an 'int' value.

Signed-off-by: David Laight <david.laight@aculab.com>
---
v3; No change
v2: No change
 include/linux/minmax.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index ccfbe003a643..f56611ab486a 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -24,8 +24,9 @@
 	__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))
+#define __types_ok(x, y) 			\
+	(__is_signed(x) == __is_signed(y) ||	\
+		__is_signed((x) + 0) == __is_signed((y) + 0))
 
 #define __cmp_op_min <
 #define __cmp_op_max >
-- 
2.17.1

-
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