drivers/net/ethernet/mediatek/mtk_star_emac.c:1559:34: warning: unused variable 'mtk_star_of_match'

[kernel test robot <lkp@intel.com>]

Hi Lorenzo,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   0280e3c58f92b2fe0e8fbbdf8d386449168de4a8
commit: a3c62a042237d1adeb0290dcb768e17edd6dcd25 net: mtk_eth: add COMPILE_TEST support
date:   6 weeks ago
config: s390-buildonly-randconfig-r005-20220126 (https://download.01.org/0day-ci/archive/20220126/202201261608.BLH8XrDI-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 2a1b7aa016c0f4b5598806205bdfbab1ea2d92c4)
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 s390 cross compiling tool for clang build
        # apt-get install binutils-s390x-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a3c62a042237d1adeb0290dcb768e17edd6dcd25
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout a3c62a042237d1adeb0290dcb768e17edd6dcd25
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/net/ethernet/mediatek/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __raw_readb(PCI_IOBASE + addr);
                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/big_endian.h:36:59: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
                                                             ^
   include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
   #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
                                                        ^
   In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
   #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
                                                        ^
   In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writeb(value, PCI_IOBASE + addr);
                               ~~~~~~~~~~ ^
   include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsb(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsw(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsl(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesb(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
   include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesw(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
   include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesl(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
>> drivers/net/ethernet/mediatek/mtk_star_emac.c:1559:34: warning: unused variable 'mtk_star_of_match' [-Wunused-const-variable]
   static const struct of_device_id mtk_star_of_match[] = {
                                    ^
   13 warnings generated.


vim +/mtk_star_of_match +1559 drivers/net/ethernet/mediatek/mtk_star_emac.c

8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1558  
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 @1559  static const struct of_device_id mtk_star_of_match[] = {
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1560  	{ .compatible = "mediatek,mt8516-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1561  	{ .compatible = "mediatek,mt8518-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1562  	{ .compatible = "mediatek,mt8175-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1563  	{ }
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1564  };
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1565  MODULE_DEVICE_TABLE(of, mtk_star_of_match);
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22  1566  

:::::: The code at line 1559 was first introduced by commit
:::::: 8c7bd5a454ffc2b0518d1499c4af95f00291d2af net: ethernet: mtk-star-emac: new driver

:::::: TO: Bartosz Golaszewski <bgolaszewski@baylibre.com>
:::::: CC: David S. Miller <davem@davemloft.net>

---
0-DAY CI Kernel Test Service, Intel Corporation
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