On 4/18/09, Johannes Berg <[email protected]> wrote:
> On Sat, 2009-04-18 at 14:29 +0100, Alan Jenkins wrote:
>
>> API nit:
>>
>> * This function tells the rfkill core that the device is capable of
>> * remembering soft blocks (which it is notified of via the set_block
>> * method) -- this means that the driver may ignore the return value
>> * from rfkill_set_hw_state().
>>
>> Doesn't this conflict with the declaration of rfkill_set_hw_state() as
>> __must_check?
>
> Yeah, in a way it does, but I figure it's rare enough that those who
> really can ignore it can write
> (void) rfkill_set_hw_state(...)
>
> Don't really have a strong opinion, it just seemed the mistake in the
> other direction would be more common.
It seems my GCC has a stronger definition of "must" than you do :-). I can't get rid of the warning by casting it to void. So I'm not sure __must_check is really appropriate here.
drivers/platform/x86/hp-wmi.c: In function ‘hp_wmi_bios_setup’:
drivers/platform/x86/hp-wmi.c:467: warning: ignoring return value of ‘rfkill_set_hw_state’, declared with attribute warn_unused_result
$ grep -n rfkill_set_hw_state drivers/platform/x86/hp-wmi.c
467: (void) rfkill_set_hw_state(wifi_rfkill,
$ gcc -v
Using built-in specs.
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr --enable-shared --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.2 --program-suffix=-4.2 --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc --enable-mpfr --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.2.4 (Ubuntu 4.2.4-1ubuntu3)
Thanks
Alan
On Sat, 2009-07-18 at 16:46 +0100, Alan Jenkins wrote:
> It seems my GCC has a stronger definition of "must" than you do :-).
> I can't get rid of the warning by casting it to void. So I'm not sure
> __must_check is really appropriate here.
Heh, my gcc agrees with you :)
I'm happy to remove it -- want to send a patch?
johannes
On Sat, 2009-07-18 at 19:20 +0100, Alan Jenkins wrote:
> Some drivers don't need the return value of rfkill_set_hw_state(),
> so it should not be marked as __must_check.
>
> Signed-off-by: Alan Jenkins <[email protected]>
Acked-by: Johannes Berg <[email protected]>
Thanks.
> ---
> include/linux/rfkill.h | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
> index f3d5812..1020290 100644
> --- a/include/linux/rfkill.h
> +++ b/include/linux/rfkill.h
> @@ -238,7 +238,7 @@ void rfkill_destroy(struct rfkill *rfkill);
> * should be blocked) so that drivers need not keep track of the soft
> * block state -- which they might not be able to.
> */
> -bool __must_check rfkill_set_hw_state(struct rfkill *rfkill, bool blocked);
> +bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked);
>
> /**
> * rfkill_set_sw_state - Set the internal rfkill software block state
Some drivers don't need the return value of rfkill_set_hw_state(),
so it should not be marked as __must_check.
Signed-off-by: Alan Jenkins <[email protected]>
---
include/linux/rfkill.h | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
index f3d5812..1020290 100644
--- a/include/linux/rfkill.h
+++ b/include/linux/rfkill.h
@@ -238,7 +238,7 @@ void rfkill_destroy(struct rfkill *rfkill);
* should be blocked) so that drivers need not keep track of the soft
* block state -- which they might not be able to.
*/
-bool __must_check rfkill_set_hw_state(struct rfkill *rfkill, bool blocked);
+bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked);
/**
* rfkill_set_sw_state - Set the internal rfkill software block state
--
1.6.3.2