[PATCH net-next 4/7] drivers: net: smc911x: Fix set but unused status because of DBG macro

From: Andrew Lunn <andrew@lunn.ch>
To: Jakub Kicinski <kuba@kernel.org>
Cc: netdev <netdev@vger.kernel.org>, Nicolas Pitre <nico@fluxnic.net>,
	Andrew Lunn <andrew@lunn.ch>
Subject: [PATCH net-next 4/7] drivers: net: smc911x: Fix set but unused status because of DBG macro
Date: Sat, 31 Oct 2020 01:49:55 +0100	[thread overview]
Message-ID: <20201031004958.1059797-5-andrew@lunn.ch> (raw)
In-Reply-To: <20201031004958.1059797-1-andrew@lunn.ch>

drivers/net/ethernet/smsc/smc911x.c: In function ‘smc911x_timeout’:
drivers/net/ethernet/smsc/smc911x.c:1251:6: warning: variable ‘status’ set but not used [-Wunused-but-set-variable]
 1251 |  int status, mask;

The status is read in order to print it via the DBG macro. However,
due to the way DBG is disabled, the compiler never sees it being used.

Change the DBG macro to actually make use of the passed parameters,
and the leave the optimiser to remove the unwanted code inside the if
(0).

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
---
 drivers/net/ethernet/smsc/smc911x.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/smsc/smc911x.c b/drivers/net/ethernet/smsc/smc911x.c
index 8f748a0c057e..33d0398c182e 100644
--- a/drivers/net/ethernet/smsc/smc911x.c
+++ b/drivers/net/ethernet/smsc/smc911x.c
@@ -102,7 +102,11 @@ MODULE_ALIAS("platform:smc911x");
 
 #define PRINTK(dev, args...)   netdev_info(dev, args)
 #else
-#define DBG(n, dev, args...)   do { } while (0)
+#define DBG(n, dev, args...)			 \
+	do {					 \
+		if (0)				 \
+			netdev_dbg(dev, args);	 \
+	} while (0)
 #define PRINTK(dev, args...)   netdev_dbg(dev, args)
 #endif
 
-- 
2.28.0

