Re: [PATCH] rtlwifi: rtl8192cu: Remove variable self-assignment in rf.c

From: Larry Finger
Date: Wed Feb 07 2018 - 15:36:06 EST


On 02/07/2018 02:26 PM, Matthias Kaehlcke wrote:
In _rtl92c_get_txpower_writeval_by_regulatory() the variable writeVal
is assigned to itself in an if ... else statement, apparently only to
document that the branch condition is handled and that a previously read
value should be returned unmodified. The self-assignment causes clang to
raise the following warning:

drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c:304:13:
error: explicitly assigning value of variable of type 'u32'
(aka 'unsigned int') to itself [-Werror,-Wself-assign]
writeVal = writeVal;

Replace the self-assignment with a semicolon, which still serves to
document the 'handling' of the branch condition.

Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
---
drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c
index 9cff6bc4049c..4db92496c122 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rf.c
@@ -301,7 +301,7 @@ static void _rtl92c_get_txpower_writeval_by_regulatory(struct ieee80211_hw *hw,
writeVal = writeVal - 0x06060606;
else if (rtlpriv->dm.dynamic_txhighpower_lvl ==
TXHIGHPWRLEVEL_BT2)
- writeVal = writeVal;
+ ;
*(p_outwriteval + rf) = writeVal;
}
}


As the branch condition does nothing, why not remove it and save the compiler's optimizer a bit of work? The code looks strange, but it matches the rest of Realtek's USB drivers.

Larry