arch/sparc/include/asm/io_64.h:175:16: warning: 'reg' is used uninitialized in this function

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   4b6c093e21d36bede0fd88fd0aeb3b03647260e4
commit: 2a6c0b82e65128c73b5102e00e031c5e58bb3504 USB: PHY: JZ4770: Add support for new Ingenic SoCs.
date:   3 weeks ago
config: sparc64-randconfig-r002-20200816 (attached as .config)
compiler: sparc64-linux-gcc (GCC) 9.3.0
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
        git checkout 2a6c0b82e65128c73b5102e00e031c5e58bb3504
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sparc64 

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

All warnings (new ones prefixed by >>):

   In file included from arch/sparc/include/asm/io.h:5,
                    from include/linux/io.h:13,
                    from drivers/usb/phy/phy-jz4770.c:10:
   drivers/usb/phy/phy-jz4770.c: In function 'ingenic_usb_phy_init':
>> arch/sparc/include/asm/io_64.h:175:16: warning: 'reg' is used uninitialized in this function [-Wuninitialized]
     175 | #define writel writel
         |                ^~~~~~
   drivers/usb/phy/phy-jz4770.c:161:6: note: 'reg' was declared here
     161 |  u32 reg;
         |      ^~~

# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2a6c0b82e65128c73b5102e00e031c5e58bb3504
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 2a6c0b82e65128c73b5102e00e031c5e58bb3504
vim +/reg +175 arch/sparc/include/asm/io_64.h

f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  174  
79294d7eff89f65 arch/sparc/include/asm/io_64.h Sam Ravnborg  2014-07-20 @175  #define writel writel
7c3969c3a4f3593 arch/sparc/include/asm/io_64.h Arnd Bergmann 2014-11-19  176  #define writel_relaxed writel
79294d7eff89f65 arch/sparc/include/asm/io_64.h Sam Ravnborg  2014-07-20  177  static inline void writel(u32 l, volatile void __iomem *addr)
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  178  {
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  179  	__asm__ __volatile__("stwa\t%r0, [%1] %2\t/* pci_writel */"
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  180  			     : /* no outputs */
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  181  			     : "Jr" (l), "r" (addr), "i" (ASI_PHYS_BYPASS_EC_E_L)
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  182  			     : "memory");
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  183  }
f5e706ad886b6a5 include/asm-sparc/io_64.h      Sam Ravnborg  2008-07-17  184  

:::::: The code at line 175 was first introduced by commit
:::::: 79294d7eff89f65d2e58021bca81437e88fa61e3 sparc64: remove macro indirection in io_64.h

:::::: TO: Sam Ravnborg <sam@xxxxxxxxxxxx>
:::::: CC: David S. Miller <davem@xxxxxxxxxxxxx>

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

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