linux-kernel - [PATCH next 10/11] block: Use a boolean expression instead of max() on booleans

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Message-ID: <b564df3f987e4371a445840df1f70561@AcuMS.aculab.com>
Date: Sun, 28 Jan 2024 19:35:38 +0000
From: David Laight <David.Laight@...LAB.COM>
To: "'linux-kernel@...r.kernel.org'" <linux-kernel@...r.kernel.org>, "'Linus
 Torvalds'" <torvalds@...ux-foundation.org>, 'Netdev'
	<netdev@...r.kernel.org>, "'dri-devel@...ts.freedesktop.org'"
	<dri-devel@...ts.freedesktop.org>
CC: 'Andy Shevchenko' <andriy.shevchenko@...ux.intel.com>, 'Andrew Morton'
	<akpm@...ux-foundation.org>, "'Matthew Wilcox (Oracle)'"
	<willy@...radead.org>, 'Christoph Hellwig' <hch@...radead.org>, "'Dan
 Carpenter'" <dan.carpenter@...aro.org>, 'Linus Walleij'
	<linus.walleij@...aro.org>, "'David S . Miller'" <davem@...emloft.net>,
	"'linux-btrfs@...r.kernel.org'" <linux-btrfs@...r.kernel.org>, 'Jens Axboe'
	<axboe@...nel.dk>
Subject: [PATCH next 10/11] block: Use a boolean expression instead of max()
 on booleans

blk_stack_limits() contains:
	t->zoned = max(t->zoned, b->zoned);
These are bool, so it is just a bitwise or.
However it generates:
error: comparison of constant â€˜0â€™ with boolean expression is always true [-Werror=bool-compare]
inside the signedness check that max() does unless a '+ 0' is added.
It is a shame the compiler generates this warning for code that will
be optimised away.

Change so that the extra '+ 0' can be removed.

Signed-off-by: David Laight <david.laight@...lab.com>
---
 block/blk-settings.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 06ea91e51b8b..9ca21fea039d 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -688,7 +688,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 						   b->max_secure_erase_sectors);
 	t->zone_write_granularity = max(t->zone_write_granularity,
 					b->zone_write_granularity);
-	t->zoned = max(t->zoned, b->zoned);
+	t->zoned = t->zoned | b->zoned;
 	return ret;
 }
 EXPORT_SYMBOL(blk_stack_limits);
-- 
2.17.1

-
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