| Message ID | 20240419-alsa-scarlett2-fix-wsometimes-uninitialized-v1-1-e2ace8642e08@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ALSA: scarlett2: Zero initialize ret in scarlett2_ag_target_ctl_get() | expand |
On Sat, 20 Apr 2024 02:25:59 +0200, Nathan Chancellor wrote: > > Clang warns (or errors with CONFIG_WERROR): > > sound/usb/mixer_scarlett2.c:3697:6: error: variable 'err' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] > 3697 | if (private->autogain_updated) { > | ^~~~~~~~~~~~~~~~~~~~~~~~~ > sound/usb/mixer_scarlett2.c:3707:9: note: uninitialized use occurs here > 3707 | return err; > | ^~~ > sound/usb/mixer_scarlett2.c:3697:2: note: remove the 'if' if its condition is always true > 3697 | if (private->autogain_updated) { > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > sound/usb/mixer_scarlett2.c:3688:9: note: initialize the variable 'err' to silence this warning > 3688 | int err; > | ^ > | = 0 > 1 error generated. > > Initialize ret to zero to ensure ret is initialized in all paths within > scarlett2_ag_target_ctl_get(), which matches the style of other > functions in this driver. > > Fixes: e30ea5340c25 ("ALSA: scarlett2: Add autogain target controls") > Signed-off-by: Nathan Chancellor <nathan@kernel.org> Thanks, applied now. > --- > FWIW, a lot of the functions that end in just 'mutex_unlock()' before > returning could probably benefit from the cleanup.h infrastructure, > which would help with the scope of err in this particular function, but > I decided to go with the most minimal fix here. Yeah, we can clean up lots of such code now. If it were a new code file, I'd suggest it, but since it was an extention of the existing code, I accepted as is. thanks, Takashi
diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c index a2de31a0371b..b251d25f2a85 100644 --- a/sound/usb/mixer_scarlett2.c +++ b/sound/usb/mixer_scarlett2.c @@ -3685,7 +3685,7 @@ static int scarlett2_ag_target_ctl_get( struct usb_mixer_elem_info *elem = kctl->private_data; struct usb_mixer_interface *mixer = elem->head.mixer; struct scarlett2_data *private = mixer->private_data; - int err; + int err = 0; mutex_lock(&private->data_mutex);
Clang warns (or errors with CONFIG_WERROR): sound/usb/mixer_scarlett2.c:3697:6: error: variable 'err' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] 3697 | if (private->autogain_updated) { | ^~~~~~~~~~~~~~~~~~~~~~~~~ sound/usb/mixer_scarlett2.c:3707:9: note: uninitialized use occurs here 3707 | return err; | ^~~ sound/usb/mixer_scarlett2.c:3697:2: note: remove the 'if' if its condition is always true 3697 | if (private->autogain_updated) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sound/usb/mixer_scarlett2.c:3688:9: note: initialize the variable 'err' to silence this warning 3688 | int err; | ^ | = 0 1 error generated. Initialize ret to zero to ensure ret is initialized in all paths within scarlett2_ag_target_ctl_get(), which matches the style of other functions in this driver. Fixes: e30ea5340c25 ("ALSA: scarlett2: Add autogain target controls") Signed-off-by: Nathan Chancellor <nathan@kernel.org> --- FWIW, a lot of the functions that end in just 'mutex_unlock()' before returning could probably benefit from the cleanup.h infrastructure, which would help with the scope of err in this particular function, but I decided to go with the most minimal fix here. --- sound/usb/mixer_scarlett2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: 32cb23a0f911317cdb5030035e49a204aa86fef5 change-id: 20240419-alsa-scarlett2-fix-wsometimes-uninitialized-d44f7659b52a Best regards,