RE: [PATCH v2 01/13] block/stream: Remove redundant statement in stream_run()

[Chenqun (kuhn)]

>-----Original Message-----
>From: Kevin Wolf [mailto:address@hidden]
>Sent: Wednesday, February 26, 2020 5:51 PM
>To: Chenqun (kuhn) <address@hidden>
>Cc: address@hidden; address@hidden;
>address@hidden; Zhanghailiang <address@hidden>;
>Euler Robot <address@hidden>; John Snow <address@hidden>;
>Max Reitz <address@hidden>
>Subject: Re: [PATCH v2 01/13] block/stream: Remove redundant statement in
>stream_run()
>
>Am 26.02.2020 um 09:46 hat address@hidden geschrieben:
>> From: Chen Qun <address@hidden>
>>
>> Clang static code analyzer show warning:
>>   block/stream.c:186:9: warning: Value stored to 'ret' is never read
>>         ret = 0;
>>         ^     ~
>> Reported-by: Euler Robot <address@hidden>
>> Signed-off-by: Chen Qun <address@hidden>
>> Reviewed-by: John Snow <address@hidden>
>
>Let's mention that this is unnecessary since commit 1d809098aa9.
>
>Since the same commit, the initialisation 'int ret = 0;' is unnecessary because
>we never read ret before overwriting the initial value. We could clean this up
>in the same patch.

Yes, we can clean it and move 'ret'  declaration to the for() statement.

Modify just Like this：
@@ -114,7 +114,6 @@ static int coroutine_fn stream_run(Job *job, Error **errp)
     int64_t offset = 0;
     uint64_t delay_ns = 0;
     int error = 0;
-    int ret = 0;
     int64_t n = 0; /* bytes */

     if (bs == s->bottom) {
@@ -139,6 +138,7 @@ static int coroutine_fn stream_run(Job *job, Error **errp)

     for ( ; offset < len; offset += n) {
         bool copy;
+        int ret;

         /* Note that even when no rate limit is applied we need to yield
          * with no pending I/O here so that bdrv_drain_all() returns.
@@ -183,7 +183,6 @@ static int coroutine_fn stream_run(Job *job, Error **errp)
                 break;
             }
         }
-        ret = 0;

         /* Publish progress */
         job_progress_update(&s->common.job, n);

>
>With or without the changes:
>
>Reviewed-by: Kevin Wolf <address@hidden>