Hi Andy,

I love your patch! Yet something to improve:

[auto build test ERROR on linux/master]
[also build test ERROR on linus/master nfsd/nfsd-next v5.12 next-20210504]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Andy-Shevchenko/lib-string_helpers-get-rid-of-ugly-_escape_mem_ascii/20210504-182828
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 1fe5501ba1abf2b7e78295df73675423bd6899a0
config: powerpc64-randconfig-r035-20210504 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 8f5a2a5836cc8e4c1def2bdeb022e7b496623439)
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 powerpc64 cross compiling tool for clang build
        # apt-get install binutils-powerpc64-linux-gnu
        # https://github.com/0day-ci/linux/commit/047508aa8c09cb58cf304e9025283021731b3921
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Andy-Shevchenko/lib-string_helpers-get-rid-of-ugly-_escape_mem_ascii/20210504-182828
        git checkout 047508aa8c09cb58cf304e9025283021731b3921
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=powerpc64 

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

All errors (new ones prefixed by >>):

   In file included from arch/powerpc/kernel/prom_init.c:24:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:10:
   In file included from arch/powerpc/include/asm/hardirq.h:6:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/powerpc/include/asm/io.h:619:
   arch/powerpc/include/asm/io-defs.h:45:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
   DEF_PCI_AC_NORET(insw, (unsigned long p, void *b, unsigned long c),
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
                   __do_##name al;                                 \
                   ^~~~~~~~~~~~~~
   <scratch space>:79:1: note: expanded from here
   __do_insw
   ^
   arch/powerpc/include/asm/io.h:557:56: note: expanded from macro '__do_insw'
   #define __do_insw(p, b, n)      readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n))
                                          ~~~~~~~~~~~~~~~~~~~~~^
   In file included from arch/powerpc/kernel/prom_init.c:24:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:10:
   In file included from arch/powerpc/include/asm/hardirq.h:6:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/powerpc/include/asm/io.h:619:
   arch/powerpc/include/asm/io-defs.h:47:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
   DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c),
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
                   __do_##name al;                                 \
                   ^~~~~~~~~~~~~~
   <scratch space>:81:1: note: expanded from here
   __do_insl
   ^
   arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl'
   #define __do_insl(p, b, n)      readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n))
                                          ~~~~~~~~~~~~~~~~~~~~~^
   In file included from arch/powerpc/kernel/prom_init.c:24:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:10:
   In file included from arch/powerpc/include/asm/hardirq.h:6:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/powerpc/include/asm/io.h:619:
   arch/powerpc/include/asm/io-defs.h:49:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
   DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c),
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
                   __do_##name al;                                 \
                   ^~~~~~~~~~~~~~
   <scratch space>:83:1: note: expanded from here
   __do_outsb
   ^
   arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb'
   #define __do_outsb(p, b, n)     writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
                                           ~~~~~~~~~~~~~~~~~~~~~^
   In file included from arch/powerpc/kernel/prom_init.c:24:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:10:
   In file included from arch/powerpc/include/asm/hardirq.h:6:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/powerpc/include/asm/io.h:619:
   arch/powerpc/include/asm/io-defs.h:51:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
   DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c),
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
                   __do_##name al;                                 \
                   ^~~~~~~~~~~~~~
   <scratch space>:85:1: note: expanded from here
   __do_outsw
   ^
   arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw'
   #define __do_outsw(p, b, n)     writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
                                           ~~~~~~~~~~~~~~~~~~~~~^
   In file included from arch/powerpc/kernel/prom_init.c:24:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:10:
   In file included from arch/powerpc/include/asm/hardirq.h:6:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/powerpc/include/asm/io.h:619:
   arch/powerpc/include/asm/io-defs.h:53:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
   DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c),
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
                   __do_##name al;                                 \
                   ^~~~~~~~~~~~~~
   <scratch space>:87:1: note: expanded from here
   __do_outsl
   ^
   arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl'
   #define __do_outsl(p, b, n)     writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
                                           ~~~~~~~~~~~~~~~~~~~~~^
>> arch/powerpc/kernel/prom_init.c:704:9: error: 'isxdigit' macro redefined [-Werror,-Wmacro-redefined]
   #define isxdigit(c)     (('0' <= (c) && (c) <= '9') \
           ^
   include/linux/ctype.h:35:9: note: previous definition is here
   #define isxdigit(c)     ((__ismask(c)&(_D|_X)) != 0)
           ^
>> arch/powerpc/kernel/prom_init.c:709:9: error: 'islower' macro redefined [-Werror,-Wmacro-redefined]
   #define islower(c)      ('a' <= (c) && (c) <= 'z')
           ^
   include/linux/ctype.h:29:9: note: previous definition is here
   #define islower(c)      ((__ismask(c)&(_L)) != 0)
           ^
>> arch/powerpc/kernel/prom_init.c:710:9: error: 'toupper' macro redefined [-Werror,-Wmacro-redefined]
   #define toupper(c)      (islower(c) ? ((c) - 'a' + 'A') : (c))
           ^
   include/linux/ctype.h:64:9: note: previous definition is here
   #define toupper(c) __toupper(c)
           ^
   9 errors generated.


vim +/isxdigit +704 arch/powerpc/kernel/prom_init.c

9b6b563c0d2d25 Paul Mackerras  2005-10-06  702  
5827d4165ac608 Anton Blanchard 2012-11-26  703  /* We can't use the standard versions because of relocation headaches. */
cf68787b68a201 Benjamin Krill  2009-07-27 @704  #define isxdigit(c)	(('0' <= (c) && (c) <= '9') \
cf68787b68a201 Benjamin Krill  2009-07-27  705  			 || ('a' <= (c) && (c) <= 'f') \
cf68787b68a201 Benjamin Krill  2009-07-27  706  			 || ('A' <= (c) && (c) <= 'F'))
cf68787b68a201 Benjamin Krill  2009-07-27  707  
cf68787b68a201 Benjamin Krill  2009-07-27  708  #define isdigit(c)	('0' <= (c) && (c) <= '9')
cf68787b68a201 Benjamin Krill  2009-07-27 @709  #define islower(c)	('a' <= (c) && (c) <= 'z')
cf68787b68a201 Benjamin Krill  2009-07-27 @710  #define toupper(c)	(islower(c) ? ((c) - 'a' + 'A') : (c))
cf68787b68a201 Benjamin Krill  2009-07-27  711  

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