<asm-generic/barrier.h> uses barrier() but needs to #include <linux/compiler.h> to get a generic definition of it to fix build errors in arch/alpha/ builds when CONFIG_SMP is not enabled.
Fixes build errors like this (there are several like this): [49 in the kernel config that was supplied by the 0day bot] In file included from ../arch/alpha/include/asm/barrier.h:21, from ../arch/alpha/include/asm/atomic.h:6, from ../include/linux/atomic.h:7, from ../include/linux/dcache.h:5, from ../fs/proc/util.c:1: ../arch/alpha/include/asm/atomic.h: In function 'atomic_add_return_relaxed': ../include/asm-generic/barrier.h:78:18: error: implicit declaration of function 'barrier' [-Werror=implicit-function-declaration] 78 | #define smp_mb() barrier() | ^~~~~~~ Fixes: 885df91ca357 ("Create asm-generic/barrier.h") Signed-off-by: Randy Dunlap <rdun...@infradead.org> Reported-by: kernel test robot <l...@intel.com> Cc: David Howells <dhowe...@redhat.com> Cc: Arnd Bergmann <a...@arndb.de> Cc: Richard Henderson <r...@twiddle.net> Cc: Ivan Kokshaysky <i...@jurassic.park.msu.ru> Cc: Matt Turner <matts...@gmail.com> Cc: linux-al...@vger.kernel.org --- include/asm-generic/barrier.h | 1 + 1 file changed, 1 insertion(+) --- linux-next-20201030.orig/include/asm-generic/barrier.h +++ linux-next-20201030/include/asm-generic/barrier.h @@ -13,6 +13,7 @@ #ifndef __ASSEMBLY__ +#include <linux/compiler.h> #include <asm/rwonce.h> #ifndef nop