block: use unitialized_var() in bio_alloc_bioset()

Better than setting idx to some random value and it silences the
same bogus gcc warning.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/fs/bio.c b/fs/bio.c
index 799f86deff243213256103ee76ff7560098fe965..2fa04ff8670337cc8818a3dcc0c30e18668fd17a 100644 (file)
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -158,7 +158,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
 
                bio_init(bio);
                if (likely(nr_iovecs)) {
-                       unsigned long idx = 0; /* shut up gcc */
+                       unsigned long uninitialized_var(idx);
 
                        bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
                        if (unlikely(!bvl)) {