[PATCH] block: Silence spurious compiler warnings

[Kent Overstreet <kmo@daterainc.com>]

>From 46e7081430f5f483906f496733a23f8e9d898879 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kmo@daterainc.com>
Date: Tue, 26 Nov 2013 16:36:49 -0800
Subject: [PATCH] block: Silence spurious compiler warnings

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
---

On Tue, Nov 26, 2013 at 12:02:08PM -0700, Jens Axboe wrote:
> On 11/26/2013 12:01 PM, Olof Johansson wrote:
> > I just noticed that i see this with gcc 4.7.0, but 4.8.1 does not warn.
> 
> That's good, because it's not a bug. But arguably we should shut up 4.7
> as well, however...

Here you go:

 block/blk-merge.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 05c17be..0b097f6 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -89,6 +89,8 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
 	struct bio_vec end_bv, nxt_bv;
 	struct bvec_iter iter;
 
+	uninitialized_var(end_bv);
+
 	if (!blk_queue_cluster(q))
 		return 0;
 
@@ -173,6 +175,8 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
 	struct scatterlist *sg;
 	int nsegs, cluster;
 
+	uninitialized_var(bvprv);
+
 	nsegs = 0;
 	cluster = blk_queue_cluster(q);
 
@@ -235,6 +239,8 @@ int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
 	int nsegs, cluster;
 	struct bvec_iter iter;
 
+	uninitialized_var(bvprv);
+
 	nsegs = 0;
 	cluster = blk_queue_cluster(q);
 
-- 
1.8.4.4