From: Arnd Bergmann <arnd@xxxxxxxx> The sysfs_create_link() return code is marked as __must_check, but the module_add_driver() function tries hard to not care, by assigning the return code to a variable. When building with 'make W=1', gcc still warns because this variable is only assigned but not used: drivers/base/module.c: In function 'module_add_driver': drivers/base/module.c:36:6: warning: variable 'no_warn' set but not used [-Wunused-but-set-variable] Add an explicit cast to void to prevent this check as well. Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: linux-modules@xxxxxxxxxxxxxxx Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Fixes: e17e0f51aeea ("Driver core: show drivers in /sys/module/") See-also: 4a7fb6363f2d ("add __must_check to device management code") Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- I'm not entirely sure what bug the __must_check on sysfs_create_link() is trying to prevent, or why the module loader code is allowed to ignore this. It would be nice to have an Ack from the sysfs maintainers on this. --- drivers/base/module.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/base/module.c b/drivers/base/module.c index 46ad4d636731..0180dbcf2240 100644 --- a/drivers/base/module.c +++ b/drivers/base/module.c @@ -67,6 +67,8 @@ void module_add_driver(struct module *mod, struct device_driver *drv) driver_name); kfree(driver_name); } + + (void)no_warn; } void module_remove_driver(struct device_driver *drv) -- 2.39.2