tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/core head: 9df16fbedc1deaf5b63a1b025776bd8c78a9686d commit: f9967fb3a28f87f8b8b6ae286dbb06902525717d [13/14] locking/mutex: Introduce __mutex_trylock_or_handoff() config: mips-randconfig-r015-20210702 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9eb613b2de3163686b1a4bd1160f15ac56a4b083) 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 mips cross compiling tool for clang build # apt-get install binutils-mips-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?id=f9967fb3a28f87f8b8b6ae286dbb06902525717d git remote add peterz-queue https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git git fetch --no-tags peterz-queue locking/core git checkout f9967fb3a28f87f8b8b6ae286dbb06902525717d # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=mips SHELL=/bin/bash kernel/locking/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> kernel/locking/mutex.c:143:35: warning: unused function '__mutex_trylock_or_owner' static inline struct task_struct mutex ^ fatal error: error in backend: Nested variants found in inline asm string: ' .set push .set noat .set push .set arch=r4000 .if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/cmpxchg.h", .line = 163, $); 0x00 ) != -1)) : $))) ) && ( 0 ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif 1: ll $0, $2 # __cmpxchg_asm bne $0, ${3:z}, 2f .set pop move $$1, ${4:z} .set arch=r4000 sc $$1, $1 beqz $$1, 1b .set pop 2: .if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/cmpxchg.h", .line = 163, $); 0x00 ) != -1)) : $))) ) && ( 0 ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif ' clang-13: error: clang frontend command failed with exit code 70 (use -v to see invocation) clang version 13.0.0 (git://gitmirror/llvm_project cb5de7c813f976dd458bd2a7f40702ba648bf650) Target: mips-unknown-linux-gnu Thread model: posix InstalledDir: /opt/cross/clang-cb5de7c813/bin clang-13: note: diagnostic msg: Makefile arch block certs crypto drivers fs include init ipc kernel lib mm net scripts security sound source usr virt vim +/__mutex_trylock_or_owner +143 kernel/locking/mutex.c 139 140 /* 141 * Trylock variant that returns the owning task on failure. 142 */ > 143 static inline struct task_struct *__mutex_trylock_or_owner(struct mutex *lock) 144 { 145 return __mutex_trylock_common(lock, false); 146 } 147 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org