[kbuild-all] drivers/platform/surface/surface_dtx.c:530:24: sparse: sparse: incorrect type in return expression (different base types)

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: c06a2ba62fc401b7aaefd23f5d0bc06d2457ccc1 commit: 1d609992832e900378b305f9f8dcf0ce8473049e platform/surface: Add DTX driver date: 8 weeks ago config: i386-randconfig-s032-20210513 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-341-g8af24329-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 1d609992832e900378b305f9f8dcf0ce8473049e # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' 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; iwyu warnings: (new ones prefixed by >>) vim +530 drivers/platform/surface/surface_dtx.c 523 524 static __poll_t surface_dtx_poll(struct file *file, struct poll_table_struct *pt) 525 { 526 struct sdtx_client *client = file->private_data; 527 __poll_t events = 0; 528 529 if (down_read_killable(&client->ddev->lock)) 531 532 if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &client->ddev->flags)) { 533 up_read(&client->ddev->lock); 534 return EPOLLHUP | EPOLLERR; 535 } 536 537 poll_wait(file, &client->ddev->waitq, pt); 538 539 if (!kfifo_is_empty(&client->buffer)) 540 events |= EPOLLIN | EPOLLRDNORM; 541 542 up_read(&client->ddev->lock); 543 return events; 544 } 545 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org