On Mon, Apr 29, 2019 at 7:10 PM Nathan Chancellor <natechancellor@xxxxxxxxx> wrote: > > When building with -Wsometimes-uninitialized, Clang warns: > > drivers/md/dm-dust.c:216:11: warning: variable 'ret' is used > uninitialized whenever 'if' condition is false > [-Wsometimes-uninitialized] > else if (bio_data_dir(bio) == WRITE) > ^~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/bio.h:69:2: note: expanded from macro 'bio_data_dir' > (op_is_write(bio_op(bio)) ? WRITE : READ) > ^ > drivers/md/dm-dust.c:219:9: note: uninitialized use occurs here > return ret; > ^~~ > drivers/md/dm-dust.c:216:7: note: remove the 'if' if its condition is > always true > else if (bio_data_dir(bio) == WRITE) > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/md/dm-dust.c:209:9: note: initialize the variable 'ret' to > silence this warning > int ret; > ^ > = 0 > 1 warning generated. > > It isn't wrong; however, bio_data_dir will only ever return READ and > WRITE so the second 'else if' can really become an 'else' to silence > this warning and not change the final meaning of the code. > > Link: https://github.com/ClangBuiltLinux/linux/issues/462 > Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > --- > drivers/md/dm-dust.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/md/dm-dust.c b/drivers/md/dm-dust.c > index 997830984893..5baeb56679ed 100644 > --- a/drivers/md/dm-dust.c > +++ b/drivers/md/dm-dust.c > @@ -213,7 +213,7 @@ static int dust_map(struct dm_target *ti, struct bio *bio) > > if (bio_data_dir(bio) == READ) > ret = dust_map_read(dd, bio->bi_iter.bi_sector, dd->fail_read_on_bb); > - else if (bio_data_dir(bio) == WRITE) > + else > ret = dust_map_write(dd, bio->bi_iter.bi_sector, dd->fail_read_on_bb); > > return ret; > -- > 2.21.0 > Thanks for the patch. Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> -- Thanks, ~Nick Desaulniers -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
