[v2,1/5] drm/imagination: Fixed warning due to implicit cast to bool

Commit Message

Donald Robson Nov. 30, 2023, 4 p.m. UTC

This line appears to confuse the compiler and had been noticed previously in
clang-tidy output. There isn't anything fundamentally wrong that I can see.
I suspect that it just looks like a mistake - hence the first note.  By making
the second operand an actual bool result, const correctness can be preserved
while silencing the warning.

>> drivers/gpu/drm/imagination/pvr_device_info.c:230:47: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand]
     230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
         |                                                      ^  ~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/imagination/pvr_device_info.c:230:47: note: use '&' for a bitwise operation
     230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
         |                                                      ^~
         |                                                      &
   drivers/gpu/drm/imagination/pvr_device_info.c:230:47: note: remove constant to silence this warning
     230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
         |                                                     ~^~~~~~~~~~~~~~~~~~~~~
   1 warning generated.

Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Fixes: 1ff76f7a5b45 ("drm/imagination: Add GPU ID parsing and firmware loading")
Signed-off-by: Donald Robson <[e-mail]>
---
 drivers/gpu/drm/imagination/pvr_device_info.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Maxime Ripard Dec. 1, 2023, 8:37 a.m. UTC | #1

On Thu, 30 Nov 2023 16:00:13 +0000, Donald Robson wrote:
> This line appears to confuse the compiler and had been noticed previously in
> clang-tidy output. There isn't anything fundamentally wrong that I can see.
> I suspect that it just looks like a mistake - hence the first note.  By making
> the second operand an actual bool result, const correctness can be preserved
> while silencing the warning.
> 
> >> drivers/gpu/drm/imagination/pvr_device_info.c:230:47: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand]
>      230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
>          |                                                      ^  ~~~~~~~~~~~~~~~~~~
>    drivers/gpu/drm/imagination/pvr_device_info.c:230:47: note: use '&' for a bitwise operation
>      230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
>          |                                                      ^~
>          |                                                      &
>    drivers/gpu/drm/imagination/pvr_device_info.c:230:47: note: remove constant to silence this warning
>      230 |         } else if (features_size == mapping_max_size && (mapping_max & 63)) {
>          |                                                     ~^~~~~~~~~~~~~~~~~~~~~
>    1 warning generated.
> 
> [...]

Applied to drm/drm-misc (drm-misc-next).

Thanks!
Maxime

Patch

diff --git a/drivers/gpu/drm/imagination/pvr_device_info.c b/drivers/gpu/drm/imagination/pvr_device_info.c
index 11e6bef52ecd..d3301cde7d11 100644
--- a/drivers/gpu/drm/imagination/pvr_device_info.c
+++ b/drivers/gpu/drm/imagination/pvr_device_info.c
@@ -227,7 +227,8 @@  int pvr_device_info_set_features(struct pvr_device *pvr_dev, const u64 *features
 	/* Verify no unsupported values in the bitmask. */
 	if (features_size > mapping_max_size) {
 		drm_warn(from_pvr_device(pvr_dev), "Unsupported features in firmware image");
-	} else if (features_size == mapping_max_size && (mapping_max & 63)) {
+	} else if (features_size == mapping_max_size &&
+		   ((mapping_max & 63) != 0)) {
 		u64 invalid_mask = ~0ull << (mapping_max & 63);
 
 		if (features[features_size - 1] & invalid_mask)