[thomas-weissschuh:b4/must_check-devm_mutex_init 2/2] include/linux/mutex.h:152:37: warning: ignoring return value of '__devm_mutex_init' declared with attribute 'warn_unused_result'

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/thomas.weissschuh/linux.git b4/must_check-devm_mutex_init
head:   1806244ad4c894932db80d79aceae7a9fb262153
commit: 1806244ad4c894932db80d79aceae7a9fb262153 [2/2] locking/mutex: Mark devm_mutex_init() as __must_check
config: i386-buildonly-randconfig-002-20241101 (https://download.01.org/0day-ci/archive/20241101/202411012055.cxXPYag2-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241101/202411012055.cxXPYag2-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411012055.cxXPYag2-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/seqlock.h:19,
                    from include/linux/mmzone.h:17,
                    from include/linux/gfp.h:7,
                    from include/linux/slab.h:16,
                    from include/linux/resource_ext.h:11,
                    from include/linux/acpi.h:13,
                    from include/linux/i2c.h:13,
                    from drivers/iio/adc/pac1921.c:10:
   drivers/iio/adc/pac1921.c: In function 'pac1921_probe':
>> include/linux/mutex.h:152:37: warning: ignoring return value of '__devm_mutex_init' declared with attribute 'warn_unused_result' [-Wunused-result]
     152 | #define devm_mutex_init(dev, mutex) __devm_mutex_init(dev, ___devm_mutex_init(mutex))
         |                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/iio/adc/pac1921.c:1174:9: note: in expansion of macro 'devm_mutex_init'
    1174 |         devm_mutex_init(dev, &priv->lock);
         |         ^~~~~~~~~~~~~~~
--
   In file included from include/linux/kernfs.h:11,
                    from include/linux/sysfs.h:16,
                    from include/linux/kobject.h:20,
                    from include/linux/energy_model.h:7,
                    from include/linux/device.h:16,
                    from drivers/iio/adc/ad4000.c:11:
   drivers/iio/adc/ad4000.c: In function 'ad4000_probe':
>> include/linux/mutex.h:152:37: warning: ignoring return value of '__devm_mutex_init' declared with attribute 'warn_unused_result' [-Wunused-result]
     152 | #define devm_mutex_init(dev, mutex) __devm_mutex_init(dev, ___devm_mutex_init(mutex))
         |                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/iio/adc/ad4000.c:640:9: note: in expansion of macro 'devm_mutex_init'
     640 |         devm_mutex_init(dev, &st->lock);
         |         ^~~~~~~~~~~~~~~


vim +152 include/linux/mutex.h

   151	
 > 152	#define devm_mutex_init(dev, mutex) __devm_mutex_init(dev, ___devm_mutex_init(mutex))
   153	

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