[kbuild-all] [pinctrl:for-next 3/47] drivers/pinctrl/bcm/pinctrl-bcm2835.c:412:14: warning: variable 'group' is used uninitialized whenever 'for' loop exits because its condition is false

tree: https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git for-next head: 04853352952b7dd17f355ed54bd81305b341af55 commit: 29d45a642d4ea8de7e89b57f856046df7c3b219f [3/47] pinctrl: bcm2835: Replace BUG with BUG_ON config: mips-randconfig-c004-20210816 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 2c6448cdc2f68f8c28fd0bd9404182b81306e6e6) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install mips cross compiling tool for clang build # apt-get install binutils-mips-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git/... git remote add pinctrl https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git git fetch --no-tags pinctrl for-next git checkout 29d45a642d4ea8de7e89b57f856046df7c3b219f # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 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 >>): for (i = 0; i < BCM2835_NUM_IRQS; i++) { ^~~~~~~~~~~~~~~~~~~~ drivers/pinctrl/bcm/pinctrl-bcm2835.c:423:10: note: uninitialized use occurs here switch (group) { ^~~~~ drivers/pinctrl/bcm/pinctrl-bcm2835.c:412:14: note: remove the condition if it is always true for (i = 0; i < BCM2835_NUM_IRQS; i++) { ^~~~~~~~~~~~~~~~~~~~ drivers/pinctrl/bcm/pinctrl-bcm2835.c:409:11: note: initialize the variable 'group' to silence this warning int group; ^ = 0 1 warning generated. vim +412 drivers/pinctrl/bcm/pinctrl-bcm2835.c 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 402 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 403 static void bcm2835_gpio_irq_handler(struct irq_desc *desc) 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 404 { 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 405 struct gpio_chip *chip = irq_desc_get_handler_data(desc); 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 406 struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 407 struct irq_chip *host_chip = irq_desc_get_chip(desc); 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 408 int irq = irq_desc_get_irq(desc); 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 409 int group; 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 410 int i; 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 411 73345a18d464b1b drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2019-08-12 @412 for (i = 0; i < BCM2835_NUM_IRQS; i++) { 73345a18d464b1b drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2019-08-12 413 if (chip->irq.parents[i] == irq) { 0d885e9da176ad3 drivers/pinctrl/bcm/pinctrl-bcm2835.c Thierry Reding 2017-07-20 414 group = i; 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 415 break; 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 416 } 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 417 } 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 418 /* This should not happen, every IRQ has a bank */ 29d45a642d4ea8d drivers/pinctrl/bcm/pinctrl-bcm2835.c Jason Wang 2021-06-24 419 BUG_ON(i == BCM2835_NUM_IRQS); 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 420 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 421 chained_irq_enter(host_chip, desc); 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 422 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 423 switch (group) { 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 424 case 0: /* IRQ0 covers GPIOs 0-27 */ 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 425 bcm2835_gpio_irq_handle_bank(pc, 0, 0x0fffffff); 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 426 break; 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 427 case 1: /* IRQ1 covers GPIOs 28-45 */ 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 428 bcm2835_gpio_irq_handle_bank(pc, 0, 0xf0000000); 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 429 bcm2835_gpio_irq_handle_bank(pc, 1, 0x00003fff); 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 430 break; b1d84a3d0a26c58 drivers/pinctrl/bcm/pinctrl-bcm2835.c Stefan Wahren 2020-02-08 431 case 2: /* IRQ2 covers GPIOs 46-57 */ 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 432 bcm2835_gpio_irq_handle_bank(pc, 1, 0x003fc000); 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 433 break; 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 434 } 00445b5d5866c7b drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 435 85ae9e512f437cd drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 436 chained_irq_exit(host_chip, desc); e1b2dc70cd5b00e drivers/pinctrl/pinctrl-bcm2835.c Simon Arlott 2012-09-27 437 } e1b2dc70cd5b00e drivers/pinctrl/pinctrl-bcm2835.c Simon Arlott 2012-09-27 438 :::::: The code at line 412 was first introduced by commit :::::: 73345a18d464b1b945b29f54f630ace6873344e2 pinctrl: bcm2835: Pass irqchip when adding gpiochip :::::: TO: Linus Walleij <linus.walleij(a)linaro.org&gt; :::::: CC: Linus Walleij <linus.walleij(a)linaro.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org