On 13.11.20 23:52, Randy Dunlap wrote: > Building on arch/s390/ flags this as an error, so add the > __noreturn attribute modifier to prevent the build error. > > cc1: some warnings being treated as errors > ../drivers/md/dm-writecache.c: In function 'persistent_memory_claim': > ../drivers/md/dm-writecache.c:323:1: error: no return statement in function returning non-void [-Werror=return-type] ok with me, but I am asking why the unreachable macro is not good enough. For x86 it obviously is. form arch/s390/include/asm/bug.h #define BUG() do { \ __EMIT_BUG(0); \ unreachable(); \ } while (0) > > Fixes: 48debafe4f2f ("dm: add writecache target") > Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > Cc: Mikulas Patocka <mpatocka@xxxxxxxxxx> > Cc: Alasdair Kergon <agk@xxxxxxxxxx> > Cc: Mike Snitzer <snitzer@xxxxxxxxxx> > Cc: dm-devel@xxxxxxxxxx > Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> > Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> > Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx> > Cc: linux-s390@xxxxxxxxxxxxxxx > --- > drivers/md/dm-writecache.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- linux-next-20201113.orig/drivers/md/dm-writecache.c > +++ linux-next-20201113/drivers/md/dm-writecache.c > @@ -317,7 +317,7 @@ err1: > return r; > } > #else > -static int persistent_memory_claim(struct dm_writecache *wc) > +static int __noreturn persistent_memory_claim(struct dm_writecache *wc) > { > BUG(); > } >