Re: [PATCH] Bluetooth: Fix abuse of the preincrement operator

From: Justin P. Mattock
Date: Mon Jun 28 2010 - 14:10:52 EST

On 06/28/2010 05:57 AM, David Howells wrote:
Fix abuse of the preincrement operator as detected when building with gcc

CC [M] drivers/bluetooth/hci_bcsp.o
drivers/bluetooth/hci_bcsp.c: In function 'bcsp_prepare_pkt':
drivers/bluetooth/hci_bcsp.c:247:20: warning: operation on 'bcsp->msgq_txseq' may be undefined

Reported-by: Justin P. Mattock<justinmattock@xxxxxxxxx>
Signed-off-by: David Howells<dhowells@xxxxxxxxxx>

drivers/bluetooth/hci_bcsp.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/bluetooth/hci_bcsp.c b/drivers/bluetooth/hci_bcsp.c
index 40aec0f..42d69d4 100644
--- a/drivers/bluetooth/hci_bcsp.c
+++ b/drivers/bluetooth/hci_bcsp.c
@@ -244,7 +244,7 @@ static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
if (rel) {
hdr[0] |= 0x80 + bcsp->msgq_txseq;
BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
- bcsp->msgq_txseq = ++(bcsp->msgq_txseq)& 0x07;
+ bcsp->msgq_txseq = (bcsp->msgq_txseq + 1)& 0x07;

if (bcsp->use_crc)

ahh.. so it's o.k. to add the value after bcsp->msgq_txseq instead of before. Anyways build clean over here..


Justin P. Mattock
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