Hi Madhavan,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   4ef8451b332662d004df269d4cdeb7d9f31419b5
commit: 3c9450c053f88e525b2db1e6990cdf34d14e7696 powerpc/perf: Fix missing is_sier_aviable() during build
date:   4 months ago
config: powerpc64-randconfig-r023-20201104 (attached as .config)
compiler: powerpc64-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
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3c9450c053f88e525b2db1e6990cdf34d14e7696
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 3c9450c053f88e525b2db1e6990cdf34d14e7696
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross 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 >>):

>> make[2]: *** [arch/powerpc/Makefile.postlink:31: vmlinux] Error 1

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