tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git debugfs_remove_return_value head: 5187c2360ee1d023078e4302dad32fda1e895772 commit: 72f2bf74b31aae983fb200aa7e84a05943bf27fc [2/8] debugfs: remove return value of debugfs_create_bool() config: i386-allyesconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/co... git remote add driver-core https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git git fetch --no-tags driver-core debugfs_remove_return_value git checkout 72f2bf74b31aae983fb200aa7e84a05943bf27fc # save the attached .config to linux build tree make W=1 ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): drivers/net/wireless/broadcom/b43legacy/debugfs.c: In function 'b43legacy_add_dynamic_debug': 354 | e->dyn_debug_dentries[id] = \ | ^ drivers/net/wireless/broadcom/b43legacy/debugfs.c:359:2: note: in expansion of macro 'add_dyn_dbg' 359 | add_dyn_dbg("debug_xmitpower", B43legacy_DBG_XMITPOWER, false); | ^~~~~~~~~~~ 354 | e->dyn_debug_dentries[id] = \ | ^ drivers/net/wireless/broadcom/b43legacy/debugfs.c:360:2: note: in expansion of macro 'add_dyn_dbg' 360 | add_dyn_dbg("debug_dmaoverflow", B43legacy_DBG_DMAOVERFLOW, false); | ^~~~~~~~~~~ 354 | e->dyn_debug_dentries[id] = \ | ^ drivers/net/wireless/broadcom/b43legacy/debugfs.c:361:2: note: in expansion of macro 'add_dyn_dbg' 361 | add_dyn_dbg("debug_dmaverbose", B43legacy_DBG_DMAVERBOSE, false); | ^~~~~~~~~~~ 354 | e->dyn_debug_dentries[id] = \ | ^ drivers/net/wireless/broadcom/b43legacy/debugfs.c:362:2: note: in expansion of macro 'add_dyn_dbg' 362 | add_dyn_dbg("debug_pwork_fast", B43legacy_DBG_PWORK_FAST, false); | ^~~~~~~~~~~ 354 | e->dyn_debug_dentries[id] = \ | ^ drivers/net/wireless/broadcom/b43legacy/debugfs.c:363:2: note: in expansion of macro 'add_dyn_dbg' 363 | add_dyn_dbg("debug_pwork_stop", B43legacy_DBG_PWORK_STOP, false); | ^~~~~~~~~~~ vim +354 drivers/net/wireless/broadcom/b43legacy/debugfs.c 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 347 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 348 static void b43legacy_add_dynamic_debug(struct b43legacy_wldev *dev) 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 349 { 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 350 struct b43legacy_dfsentry *e = dev->dfsentry; 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 351 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 352 #define add_dyn_dbg(name, id, initstate) do { \ 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 353 e->dyn_debug[id] = (initstate); \ 32b4ebfe7f12c2 drivers/net/wireless/broadcom/b43legacy/debugfs.c Greg Kroah-Hartman 2019-01-22 @354 e->dyn_debug_dentries[id] = \ 32b4ebfe7f12c2 drivers/net/wireless/broadcom/b43legacy/debugfs.c Greg Kroah-Hartman 2019-01-22 355 debugfs_create_bool(name, 0600, e->subdir, \ 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 356 &(e->dyn_debug[id])); \ 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 357 } while (0) 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 358 621a5f7ad9cd1c drivers/net/wireless/b43legacy/debugfs.c Viresh Kumar 2015-09-26 359 add_dyn_dbg("debug_xmitpower", B43legacy_DBG_XMITPOWER, false); 621a5f7ad9cd1c drivers/net/wireless/b43legacy/debugfs.c Viresh Kumar 2015-09-26 360 add_dyn_dbg("debug_dmaoverflow", B43legacy_DBG_DMAOVERFLOW, false); 621a5f7ad9cd1c drivers/net/wireless/b43legacy/debugfs.c Viresh Kumar 2015-09-26 361 add_dyn_dbg("debug_dmaverbose", B43legacy_DBG_DMAVERBOSE, false); 621a5f7ad9cd1c drivers/net/wireless/b43legacy/debugfs.c Viresh Kumar 2015-09-26 362 add_dyn_dbg("debug_pwork_fast", B43legacy_DBG_PWORK_FAST, false); 621a5f7ad9cd1c drivers/net/wireless/b43legacy/debugfs.c Viresh Kumar 2015-09-26 363 add_dyn_dbg("debug_pwork_stop", B43legacy_DBG_PWORK_STOP, false); 75388acd0cd827 drivers/net/wireless/b43legacy/debugfs.c Larry Finger 2007-09-25 364 :::::: The code at line 354 was first introduced by commit :::::: 32b4ebfe7f12c2481a2aea8372683142d1341a4e b43legacy: no need to check return value of debugfs_create functions :::::: TO: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; :::::: CC: Kalle Valo <kvalo(a)codeaurora.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org