drivers/usb/gadget/udc/s3c2410_udc.c:255:11: warning: comparison of address of 'ep->queue' equal to a null pointer is always false

From: kbuild test robot
Date: Thu Apr 23 2020 - 03:03:34 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: c578ddb39e565139897124e74e5a43e56538cb33
commit: afe956c577b2d5a3d9834e4424587c1ebcf90c4c kbuild: Enable -Wtautological-compare
date: 2 weeks ago
config: arm-tct_hammer_defconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 2de52422acf04662b45599f77c14ce1b2cec2b81)
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm cross compiling tool for clang build
# apt-get install binutils-arm-linux-gnueabi
git checkout afe956c577b2d5a3d9834e4424587c1ebcf90c4c
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> drivers/usb/gadget/udc/s3c2410_udc.c:255:11: warning: comparison of address of 'ep->queue' equal to a null pointer is always false [-Wtautological-pointer-compare]
if (&ep->queue == NULL)
~~~~^~~~~ ~~~~
1 warning generated.

vim +255 drivers/usb/gadget/udc/s3c2410_udc.c

3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 250
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 251 static void s3c2410_udc_nuke(struct s3c2410_udc *udc,
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 252 struct s3c2410_ep *ep, int status)
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 253 {
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 254 /* Sanity check */
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 @255 if (&ep->queue == NULL)
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 256 return;
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 257
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 258 while (!list_empty(&ep->queue)) {
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 259 struct s3c2410_request *req;
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 260 req = list_entry(ep->queue.next, struct s3c2410_request,
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 261 queue);
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 262 s3c2410_udc_done(ep, req, status);
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 263 }
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 264 }
3fc154b6b8134b drivers/usb/gadget/s3c2410_udc.c Arnaud Patard 2007-06-06 265

:::::: The code at line 255 was first introduced by commit
:::::: 3fc154b6b8134b98bb94d60cad9a46ec1ffbe372 USB Gadget driver for Samsung s3c2410 ARM SoC

:::::: TO: Arnaud Patard <arnaud.patard@xxxxxxxxxxx>
:::::: CC: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip