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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>
Subject: [PATCH next 4/5] minmax: Allow comparisons of 'int' against 'unsigned
 char/short'.
Thread-Topic: [PATCH next 4/5] minmax: Allow comparisons of 'int' against
 'unsigned char/short'.
Thread-Index: Adm+2sjvX0bUWWzzTwubPg2+xZ3MuA==
Date:   Tue, 25 Jul 2023 10:00:57 +0000
Message-ID: <ad23cf377fdb44be8b5ae53b33ee95a7@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>
---
 include/linux/minmax.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 179034479d5e..baffbe5c855d 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -16,7 +16,8 @@
  *   allocation usage).
  */
 #define __types_ok(x, y) \
-	(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
+	(is_signed_type(typeof(x)) == is_signed_type(typeof(y)) ||	\
+		is_signed_type(typeof((x) + 0)) == is_signed_type(typeof((y) + 0)))
 
 #define __cmp_op_min <
 #define __cmp_op_max >
-- 
2.17.1

-
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