[kbuild-all] warning: some functions compiled with BTI and some compiled without BTI

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 5e857ce6eae7ca21b2055cca4885545e29228fe2 commit: 97fed779f2a68937d9590fbbe8ed31d6ebbce5a5 arm64: bti: Provide Kconfig for kernel mode BTI date: 6 weeks ago config: arm64-randconfig-r031-20200619 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 487ca07fcc75d52755c9fe2ee05bcb3b6eeeec44) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu git checkout 97fed779f2a68937d9590fbbe8ed31d6ebbce5a5 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): lib/lzo/lzo1x_compress.c:291:5: warning: no previous prototype for function 'lzogeneric1x_1_compress' [-Wmissing-prototypes] int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len, ^ lib/lzo/lzo1x_compress.c:291:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len, ^ static 1 warning generated. -- -- lib/decompress_inflate.c:42:17: warning: no previous prototype for function '__gunzip' [-Wmissing-prototypes] STATIC int INIT __gunzip(unsigned char *buf, long len, ^ lib/decompress_inflate.c:42:8: note: declare 'static' if the function is not intended to be used outside of this translation unit STATIC int INIT __gunzip(unsigned char *buf, long len, ^ static 1 warning generated. -- lib/decompress_unxz.c:251:17: warning: no previous prototype for function 'unxz' [-Wmissing-prototypes] STATIC int INIT unxz(unsigned char *in, long in_size, ^ lib/decompress_unxz.c:251:8: note: declare 'static' if the function is not intended to be used outside of this translation unit STATIC int INIT unxz(unsigned char *in, long in_size, ^ static 1 warning generated. -- lib/radix-tree.c:291:6: warning: no previous prototype for function 'radix_tree_node_rcu_free' [-Wmissing-prototypes] void radix_tree_node_rcu_free(struct rcu_head *head) ^ lib/radix-tree.c:291:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void radix_tree_node_rcu_free(struct rcu_head *head) ^ static 1 warning generated. -- lib/compat_audit.c:31:5: warning: no previous prototype for function 'audit_classify_compat_syscall' [-Wmissing-prototypes] int audit_classify_compat_syscall(int abi, unsigned syscall) ^ lib/compat_audit.c:31:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int audit_classify_compat_syscall(int abi, unsigned syscall) ^ static 1 warning generated. -- lib/errname.c:172:2: warning: initializer overrides prior initialization of this subobject [-Winitializer-overrides] E(EDEADLK), /* EDEADLOCK */ ^~~~~~~~~~ lib/errname.c:15:67: note: expanded from macro 'E' #define E(err) [err + BUILD_BUG_ON_ZERO(err <= 0 || err > 300)] = "-" #err ^~~~~~~~ lib/errname.c:41:2: note: previous initialization is here E(EDEADLOCK), ^~~~~~~~~~~~ lib/errname.c:15:67: note: expanded from macro 'E' #define E(err) [err + BUILD_BUG_ON_ZERO(err <= 0 || err > 300)] = "-" #err ^~~~~~~~ 1 warning generated. -- lib/kunit/debugfs.c:28:6: warning: no previous prototype for function 'kunit_debugfs_cleanup' [-Wmissing-prototypes] void kunit_debugfs_cleanup(void) ^ lib/kunit/debugfs.c:28:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kunit_debugfs_cleanup(void) ^ static lib/kunit/debugfs.c:33:6: warning: no previous prototype for function 'kunit_debugfs_init' [-Wmissing-prototypes] void kunit_debugfs_init(void) ^ lib/kunit/debugfs.c:33:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kunit_debugfs_init(void) ^ static lib/kunit/debugfs.c:92:6: warning: no previous prototype for function 'kunit_debugfs_create_suite' [-Wmissing-prototypes] void kunit_debugfs_create_suite(struct kunit_suite *suite) ^ lib/kunit/debugfs.c:92:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kunit_debugfs_create_suite(struct kunit_suite *suite) ^ static lib/kunit/debugfs.c:108:6: warning: no previous prototype for function 'kunit_debugfs_destroy_suite' [-Wmissing-prototypes] void kunit_debugfs_destroy_suite(struct kunit_suite *suite) ^ lib/kunit/debugfs.c:108:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kunit_debugfs_destroy_suite(struct kunit_suite *suite) ^ static 4 warnings generated. -- lib/lz4/lz4_decompress.c:477:5: warning: no previous prototype for function 'LZ4_decompress_safe_withPrefix64k' [-Wmissing-prototypes] int LZ4_decompress_safe_withPrefix64k(const char *source, char *dest, ^ lib/lz4/lz4_decompress.c:477:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int LZ4_decompress_safe_withPrefix64k(const char *source, char *dest, ^ static lib/lz4/lz4_decompress.c:499:5: warning: no previous prototype for function 'LZ4_decompress_safe_forceExtDict' [-Wmissing-prototypes] int LZ4_decompress_safe_forceExtDict(const char *source, char *dest, ^ lib/lz4/lz4_decompress.c:499:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int LZ4_decompress_safe_forceExtDict(const char *source, char *dest, ^ static 2 warnings generated. -- lib/zlib_inflate/inffast.c:31:1: warning: unused function 'get_unaligned16' [-Wunused-function] get_unaligned16(const unsigned short *p) ^ 1 warning generated. -- lib/zstd/fse_compress.c:477:8: warning: no previous prototype for function 'FSE_sizeof_CTable' [-Wmissing-prototypes] size_t FSE_sizeof_CTable(unsigned maxSymbolValue, unsigned tableLog) ^ lib/zstd/fse_compress.c:477:1: note: declare 'static' if the function is not intended to be used outside of this translation unit size_t FSE_sizeof_CTable(unsigned maxSymbolValue, unsigned tableLog) ^ static 1 warning generated. .. --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org