[Qemu-devel] [PATCH 0/6] Remove some dead assignments from clang analyzer report

[Qemu-devel] [PATCH 0/6] Remove some dead assignments from clang analyzer report

[Amit Shah]

Running the static checker clang-analyzer on the qemu sources, I found
a few dead assignments.

This patchset removes a few of those.

Amit Shah (6):
  vl.c: Remove dead assignment
  virtio: net: remove dead assignment
  x86: translate.c: remove dead assignment
  hw/vga.c: remove dead assignment
  qcow2-refcount: remove dead assignment
  json-parser: remove dead increment

 block/qcow2-refcount.c  |    1 -
 hw/vga.c                |    1 -
 hw/virtio-net.c         |    2 +-
 json-parser.c           |    2 --
 target-i386/translate.c |    2 --
 vl.c                    |    6 +-----
 6 files changed, 2 insertions(+), 12 deletions(-)

[Qemu-devel] [PATCH 1/6] vl.c: Remove dead assignment

[Amit Shah]

clang-analyzer pointed out the value of 'sockets' is never reused.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
CC: Andre Przywara <andre.przywara@amd.com>
---
 vl.c |    6 +-----
 1 files changed, 1 insertions(+), 5 deletions(-)

diff --git a/vl.c b/vl.c
index b048e89..e49e7bd 100644
--- a/vl.c
+++ b/vl.c
@@ -2613,17 +2613,13 @@ static void smp_parse(const char *optarg)
         threads = threads > 0 ? threads : 1;
         if (smp == 0) {
             smp = cores * threads * sockets;
-        } else {
-            sockets = smp / (cores * threads);
         }
     } else {
         if (cores == 0) {
             threads = threads > 0 ? threads : 1;
             cores = smp / (sockets * threads);
         } else {
-            if (sockets == 0) {
-                sockets = smp / (cores * threads);
-            } else {
+            if (sockets) {
                 threads = smp / (cores * sockets);
             }
         }
-- 
1.6.2.5

[Qemu-devel] [PATCH 2/6] virtio: net: remove dead assignment

[Amit Shah]

clang-analyzer points out value assigned to 'len' is not used.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 hw/virtio-net.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index 02d9180..6e48997 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -532,7 +532,7 @@ static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_
         int len, total;
         struct iovec sg[VIRTQUEUE_MAX_SIZE];
 
-        len = total = 0;
+        total = 0;
 
         if ((i != 0 && !n->mergeable_rx_bufs) ||
             virtqueue_pop(n->rx_vq, &elem) == 0) {
-- 
1.6.2.5

[Qemu-devel] [PATCH 3/6] x86: translate.c: remove dead assignment

[Amit Shah]

clang-analyzer points out a redundant assignment.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 target-i386/translate.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/target-i386/translate.c b/target-i386/translate.c
index 511a4ea..8078112 100644
--- a/target-i386/translate.c
+++ b/target-i386/translate.c
@@ -2207,8 +2207,6 @@ static void gen_add_A0_ds_seg(DisasContext *s)
     if (s->override >= 0) {
         override = s->override;
         must_add_seg = 1;
-    } else {
-        override = R_DS;
     }
     if (must_add_seg) {
 #ifdef TARGET_X86_64
-- 
1.6.2.5

[Qemu-devel] [PATCH 4/6] hw/vga.c: remove dead assignment

[Amit Shah]

clang-analyzer points out a redundant assignment.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 hw/vga.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/hw/vga.c b/hw/vga.c
index d05f1f9..6a1a059 100644
--- a/hw/vga.c
+++ b/hw/vga.c
@@ -1303,7 +1303,6 @@ static void vga_draw_text(VGACommonState *s, int full_update)
     line_offset = s->line_offset;
 
     vga_get_text_resolution(s, &width, &height, &cw, &cheight);
-    x_incr = cw * ((ds_get_bits_per_pixel(s->ds) + 7) >> 3);
     if ((height * width) > CH_ATTR_SIZE) {
         /* better than nothing: exit if transient size is too big */
         return;
-- 
1.6.2.5

[Qemu-devel] [PATCH 5/6] qcow2-refcount: remove dead assignment

[Amit Shah]

clang-analyzer points out a redundant assignment.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 block/qcow2-refcount.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 54b19f8..3a2d44a 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -511,7 +511,6 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
     l2_table = NULL;
     l1_table = NULL;
     l1_size2 = l1_size * sizeof(uint64_t);
-    l1_allocated = 0;
     if (l1_table_offset != s->l1_table_offset) {
         if (l1_size2 != 0) {
             l1_table = qemu_mallocz(align_offset(l1_size2, 512));
-- 
1.6.2.5

[Qemu-devel] [PATCH 6/6] json-parser: remove dead increment

[Amit Shah]

clang-analyzer points out a redundant increment.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 json-parser.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/json-parser.c b/json-parser.c
index 7624c0f..e04932f 100644
--- a/json-parser.c
+++ b/json-parser.c
@@ -247,8 +247,6 @@ static QString *qstring_from_escaped_str(JSONParserContext *ctxt, QObject *token
         }
     }
 
-    ptr++;
-
     return str;
 
 out:
-- 
1.6.2.5

[Qemu-devel] Re: [PATCH 5/6] qcow2-refcount: remove dead assignment

[Paolo Bonzini]

On 01/13/2010 11:54 AM, Amit Shah wrote:
> clang-analyzer points out a redundant assignment.
>
> Signed-off-by: Amit Shah<amit.shah@redhat.com>
> ---
>   block/qcow2-refcount.c |    1 -
>   1 files changed, 0 insertions(+), 1 deletions(-)
>
> diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
> index 54b19f8..3a2d44a 100644
> --- a/block/qcow2-refcount.c
> +++ b/block/qcow2-refcount.c
> @@ -511,7 +511,6 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
>       l2_table = NULL;
>       l1_table = NULL;
>       l1_size2 = l1_size * sizeof(uint64_t);
> -    l1_allocated = 0;
>       if (l1_table_offset != s->l1_table_offset) {
>           if (l1_size2 != 0) {
>               l1_table = qemu_mallocz(align_offset(l1_size2, 512));

I'd remove the l1_allocated = 0 assignment in the else branch instead 
(the idea is, assign l1_allocated = 1 right after any qemu_malloc.

Paolo

[Qemu-devel] Re: [PATCH 5/6] qcow2-refcount: remove dead assignment

[Amit Shah]

On (Wed) Jan 13 2010 [12:46:22], Paolo Bonzini wrote:
> On 01/13/2010 11:54 AM, Amit Shah wrote:
>> clang-analyzer points out a redundant assignment.
>>
>> Signed-off-by: Amit Shah<amit.shah@redhat.com>
>> ---
>>   block/qcow2-refcount.c |    1 -
>>   1 files changed, 0 insertions(+), 1 deletions(-)
>>
>> diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
>> index 54b19f8..3a2d44a 100644
>> --- a/block/qcow2-refcount.c
>> +++ b/block/qcow2-refcount.c
>> @@ -511,7 +511,6 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
>>       l2_table = NULL;
>>       l1_table = NULL;
>>       l1_size2 = l1_size * sizeof(uint64_t);
>> -    l1_allocated = 0;
>>       if (l1_table_offset != s->l1_table_offset) {
>>           if (l1_size2 != 0) {
>>               l1_table = qemu_mallocz(align_offset(l1_size2, 512));
>
> I'd remove the l1_allocated = 0 assignment in the else branch instead  
> (the idea is, assign l1_allocated = 1 right after any qemu_malloc.

I thought about that too, but since the else{} part has some other code,
I decided to go that way.

(Also that if such assignments aren't placed in common code, they'll be
pointed out when someone tries to use them with the default undefined
value.)

		Amit

[Qemu-devel] Re: [PATCH 2/6] virtio: net: remove dead assignment

[Michael S. Tsirkin]

On Wed, Jan 13, 2010 at 04:24:43PM +0530, Amit Shah wrote:
> clang-analyzer points out value assigned to 'len' is not used.
> 
> Signed-off-by: Amit Shah <amit.shah@redhat.com>

Acked-by: Michael S. Tsirkin <mst@redhat.com>

> ---
>  hw/virtio-net.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/hw/virtio-net.c b/hw/virtio-net.c
> index 02d9180..6e48997 100644
> --- a/hw/virtio-net.c
> +++ b/hw/virtio-net.c
> @@ -532,7 +532,7 @@ static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_
>          int len, total;
>          struct iovec sg[VIRTQUEUE_MAX_SIZE];
>  
> -        len = total = 0;
> +        total = 0;
>  
>          if ((i != 0 && !n->mergeable_rx_bufs) ||
>              virtqueue_pop(n->rx_vq, &elem) == 0) {
> -- 
> 1.6.2.5
> 
> 

Re: [Qemu-devel] [PATCH 1/6] vl.c: Remove dead assignment

[Anthony Liguori]

On 01/13/2010 04:54 AM, Amit Shah wrote:
> clang-analyzer pointed out the value of 'sockets' is never reused.
>
> Signed-off-by: Amit Shah<amit.shah@redhat.com>
> CC: Andre Przywara<andre.przywara@amd.com>
>    

Applied.  Thanks.

Regards,

Anthony Liguori
> ---
>   vl.c |    6 +-----
>   1 files changed, 1 insertions(+), 5 deletions(-)
>
> diff --git a/vl.c b/vl.c
> index b048e89..e49e7bd 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2613,17 +2613,13 @@ static void smp_parse(const char *optarg)
>           threads = threads>  0 ? threads : 1;
>           if (smp == 0) {
>               smp = cores * threads * sockets;
> -        } else {
> -            sockets = smp / (cores * threads);
>           }
>       } else {
>           if (cores == 0) {
>               threads = threads>  0 ? threads : 1;
>               cores = smp / (sockets * threads);
>           } else {
> -            if (sockets == 0) {
> -                sockets = smp / (cores * threads);
> -            } else {
> +            if (sockets) {
>                   threads = smp / (cores * sockets);
>               }
>           }
>