[kbuild-all] [intel-lts:5.10/yocto 18526/20393] drivers/gpio/gpio-ehl-pse-plat.c:79:6: warning: no previous prototype for 'ehl_pse_gpio_free'

tree: https://github.com/intel/linux-intel-lts.git 5.10/yocto head: 2dafc777a64181d42982628c7f5907a03da5f070 commit: 0bce160955505f13b1c53ce6c48eaa49f3dd472d [18526/20393] mfd: intel-ehl-gpio: Introduce MFD framework to PSE GPIO/TGPIO config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220211/202202110420.D6I0HID3-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/intel/linux-intel-lts/commit/0bce160955505f13b1c53ce6c... git remote add intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-lts 5.10/yocto git checkout 0bce160955505f13b1c53ce6c48eaa49f3dd472d # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/crypto/ drivers/gpio/ drivers/gpu/drm/i915/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): 79 | void ehl_pse_gpio_free(struct gpio_chip *chip, unsigned int offset) | ^~~~~~~~~~~~~~~~~ drivers/gpio/gpio-ehl-pse-plat.c: In function 'ehl_pse_gpio_get_direction': drivers/gpio/gpio-ehl-pse-plat.c:175:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement] 175 | u32 reg_gpdr = intel_gpio_readl(priv->reg_base, GPDR); | ^~~ In file included from include/uapi/linux/posix_types.h:5, from include/uapi/linux/types.h:14, from include/linux/types.h:6, from include/linux/kasan-checks.h:5, from include/asm-generic/rwonce.h:26, from ./arch/x86/include/generated/asm/rwonce.h:1, from include/linux/compiler.h:246, from include/linux/ioport.h:13, from include/linux/acpi.h:12, from drivers/gpio/gpio-ehl-pse-plat.c:9: drivers/gpio/gpio-ehl-pse-plat.c: In function 'ehl_pse_gpio_probe': include/linux/stddef.h:8:14: warning: returning 'void *' from a function with return type 'int' makes integer from pointer without a cast [-Wint-conversion] 8 | #define NULL ((void *)0) | ^ drivers/gpio/gpio-ehl-pse-plat.c:378:10: note: in expansion of macro 'NULL' 378 | return NULL; | ^~~~ include/linux/stddef.h:8:14: warning: returning 'void *' from a function with return type 'int' makes integer from pointer without a cast [-Wint-conversion] 8 | #define NULL ((void *)0) | ^ drivers/gpio/gpio-ehl-pse-plat.c:382:10: note: in expansion of macro 'NULL' 382 | return NULL; | ^~~~ drivers/gpio/gpio-ehl-pse-plat.c:365:16: warning: unused variable 'base' [-Wunused-variable] 365 | void __iomem *base; | ^~~~ vim +/ehl_pse_gpio_free +79 drivers/gpio/gpio-ehl-pse-plat.c 78 80 { 81 /* decrease runtime_usage counter */ 82 pm_runtime_put_sync(chip->parent); 83 } 84 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org