On Thu, 05 Nov 2020, Dmitry Torokhov wrote:

Hi Lee,

On Wed, Nov 04, 2020 at 04:24:17PM +0000, Lee Jones wrote:

quoted

Fixes the following W=1 kernel build warning(s):

 drivers/input/mouse/synaptics.c: In function ‘synaptics_process_packet’:
 drivers/input/mouse/synaptics.c:1110:6: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Henrik Rydberg <rydberg@bitmath.org>
Cc: Peter Osterlund <redacted>
Cc: Stefan Gmeiner <redacted>
Cc: "C. Scott Ananian" <redacted>
Cc: Bruce Kalk <redacted>
Cc: this to <redacted>
Cc: linux-input@vger.kernel.org
Signed-off-by: Lee Jones <redacted>
---
 drivers/input/mouse/synaptics.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index 82577095e175e..07835939d83b9 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c

@@ -1106,8 +1106,9 @@ static void synaptics_process_packet(struct psmouse *psmouse)
 					num_fingers = hw.w + 2;
 				break;
 			case 2:
-				if (SYN_MODEL_PEN(info->model_id))
+				if (SYN_MODEL_PEN(info->model_id)) {
 					;   /* Nothing, treat a pen as a single finger */
+				}

This gives me:

WARNING: braces {} are not necessary for single statement blocks

from checkpatch.

Yes, because checkpatch just sees it as a normal single statement,
rather than an empty one.  It complains about macros that can be
compiled out too, which is even more dangerous.

GCC wins this one though, as it *knows* it's an empty statement.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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