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Message-ID: <5774DC40.8090806@cn.fujitsu.com>
Date: Thu, 30 Jun 2016 16:45:52 +0800
From: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH] dirty-bitmap: remove unnecessary return
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To: Fam Zheng <famz@redhat.com>
Cc: qemu devel <qemu-devel@nongnu.org>, Kevin Wolf <kwolf@redhat.com>, Jeff Cody <jcody@redhat.com>, Max Reitz <mreitz@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>

On 06/30/2016 04:25 PM, Fam Zheng wrote:
> On Thu, 06/30 16:01, Changlong Xie wrote:
>> Otherwise, we could never trigger assert(!bitmap->successor)
>>
>> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
>> ---
>>   block/dirty-bitmap.c | 1 -
>>   1 file changed, 1 deletion(-)
>>
>> diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
>> index 4902ca5..e9df5ac 100644
>> --- a/block/dirty-bitmap.c
>> +++ b/block/dirty-bitmap.c
>> @@ -131,7 +131,6 @@ int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
>>       if (bdrv_dirty_bitmap_frozen(bitmap)) {
>>           error_setg(errp, "Cannot create a successor for a bitmap that is "
>>                      "currently frozen");
>> -        return -1;
>>       }
>>       assert(!bitmap->successor);
>
> This is wrong. Then we will always trigger assert for a frozen bitmap.
>

IMO, when it's a frozen bitmap, we will always return -1. So 
"assert(!bitmap->successor)" is useless here, am i right?

> Fam
>
>
>