Re: [PATCH 19/36] tty: serial: lpc32xx_hs: Remove unused variable 'tmp'

From: Vladimir Zapolskiy
Date: Wed Nov 04 2020 - 15:04:51 EST


Hi Lee,

On 11/4/20 9:35 PM, Lee Jones wrote:
Fixes the following W=1 kernel build warning(s):

drivers/tty/serial/lpc32xx_hs.c: In function ‘__serial_uart_flush’:
drivers/tty/serial/lpc32xx_hs.c:244:6: warning: variable ‘tmp’ set but not used [-Wunused-but-set-variable]

Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Jiri Slaby <jirislaby@xxxxxxxxxx>
Cc: Vladimir Zapolskiy <vz@xxxxxxxxx>
Cc: Sylvain Lemieux <slemieux.tyco@xxxxxxxxx>
Cc: Kevin Wells <kevin.wells@xxxxxxx>
Cc: Roland Stigge <stigge@xxxxxxxxx>
Cc: linux-serial@xxxxxxxxxxxxxxx
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
---
drivers/tty/serial/lpc32xx_hs.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index b5898c9320361..1fa098d7aec4b 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -241,12 +241,11 @@ static unsigned int __serial_get_clock_div(unsigned long uartclk,
static void __serial_uart_flush(struct uart_port *port)
{
- u32 tmp;
int cnt = 0;
while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
(cnt++ < FIFO_READ_LIMIT))
- tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
+ readl(LPC32XX_HSUART_FIFO(port->membase));
}
static void __serial_lpc32xx_rx(struct uart_port *port)


Thank you for the change.

Acked-by: Vladimir Zapolskiy <vz@xxxxxxxxx>

I'm sure the change is correct, likely the local variable was introduced
to prevent an unwanted probable optimization by some odd/ancient compiler.

--
Best wishes,
Vladimir