[PATCH 0/4] Removal of several unused variables causing

[PATCH 0/4] Removal of several unused variables causing

[mrezanin]

From: Miroslav Rezanina <mrezanin@redhat.com>

When trying to run qemu build using clang 15.0.1 compiler with
--enable-werror option, several 'Unused but set variable' warnings
was breaking the build.

These variables show similar pattern - they are only incremented but
final value of the variable is never used. 

Removing this variables to enable using --enable-werror option
with Clang 15.0.1.

Miroslav Rezanina (4):
  rtl8139: Remove unused variable
  tulip: Remove unused variable
  qemu-img: remove unused variable
  host-libusb: Remove unused variable

 hw/net/rtl8139.c     |  2 --
 hw/net/tulip.c       |  4 +---
 hw/usb/host-libusb.c | 15 ---------------
 qemu-img.c           |  4 ++--
 4 files changed, 3 insertions(+), 22 deletions(-)

-- 
2.31.1

[PATCH 1/4] rtl8139: Remove unused variable

[mrezanin]

From: Miroslav Rezanina <mrezanin@redhat.com>

Variable send_count used in rtl8139_cplus_transmit_one function is only
incremented but never read. This causes 'Unused but set variable' warning
on Clang 15.0.1 compiler.

Removing the variable to prevent the warning.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/net/rtl8139.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c
index 6b65823b4b..e6643e3c9d 100644
--- a/hw/net/rtl8139.c
+++ b/hw/net/rtl8139.c
@@ -2156,7 +2156,6 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s)
                     ip_data_len, saved_size - ETH_HLEN, large_send_mss);
 
                 int tcp_send_offset = 0;
-                int send_count = 0;
 
                 /* maximum IP header length is 60 bytes */
                 uint8_t saved_ip_header[60];
@@ -2261,7 +2260,6 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s)
                     /* add transferred count to TCP sequence number */
                     stl_be_p(&p_tcp_hdr->th_seq,
                              chunk_size + ldl_be_p(&p_tcp_hdr->th_seq));
-                    ++send_count;
                 }
 
                 /* Stop sending this frame */
-- 
2.31.1

Re: [PATCH 1/4] rtl8139: Remove unused variable

[Thomas Huth]

On 09/11/2022 16.57, mrezanin@redhat.com wrote:
> From: Miroslav Rezanina <mrezanin@redhat.com>
> 
> Variable send_count used in rtl8139_cplus_transmit_one function is only
> incremented but never read. This causes 'Unused but set variable' warning
> on Clang 15.0.1 compiler.
> 
> Removing the variable to prevent the warning.
> 
> Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
> ---
>   hw/net/rtl8139.c | 2 --
>   1 file changed, 2 deletions(-)
> 
> diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c
> index 6b65823b4b..e6643e3c9d 100644
> --- a/hw/net/rtl8139.c
> +++ b/hw/net/rtl8139.c
> @@ -2156,7 +2156,6 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s)
>                       ip_data_len, saved_size - ETH_HLEN, large_send_mss);
>   
>                   int tcp_send_offset = 0;
> -                int send_count = 0;
>   
>                   /* maximum IP header length is 60 bytes */
>                   uint8_t saved_ip_header[60];
> @@ -2261,7 +2260,6 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s)
>                       /* add transferred count to TCP sequence number */
>                       stl_be_p(&p_tcp_hdr->th_seq,
>                                chunk_size + ldl_be_p(&p_tcp_hdr->th_seq));
> -                    ++send_count;
>                   }
>   
>                   /* Stop sending this frame */

Reviewed-by: Thomas Huth <thuth@redhat.com>

[PATCH 2/4] tulip: Remove unused variable

[mrezanin]

From: Miroslav Rezanina <mrezanin@redhat.com>

Variable n used in tulip_idblock_crc function is only incremented but never read.
This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.

Removing the variable to prevent the warning.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/net/tulip.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/hw/net/tulip.c b/hw/net/tulip.c
index b9e42c322a..c2b3b1bdfa 100644
--- a/hw/net/tulip.c
+++ b/hw/net/tulip.c
@@ -870,11 +870,10 @@ static const MemoryRegionOps tulip_ops = {
 
 static void tulip_idblock_crc(TULIPState *s, uint16_t *srom)
 {
-    int word, n;
+    int word;
     int bit;
     unsigned char bitval, crc;
     const int len = 9;
-    n = 0;
     crc = -1;
 
     for (word = 0; word < len; word++) {
@@ -887,7 +886,6 @@ static void tulip_idblock_crc(TULIPState *s, uint16_t *srom)
                 srom[len - 1] = (srom[len - 1] & 0xff00) | (unsigned short)crc;
                 break;
             }
-            n++;
             bitval = ((srom[word] >> bit) & 1) ^ ((crc >> 7) & 1);
             crc = crc << 1;
             if (bitval == 1) {
-- 
2.31.1

Re: [PATCH 2/4] tulip: Remove unused variable

[Thomas Huth]

On 09/11/2022 16.57, mrezanin@redhat.com wrote:
> From: Miroslav Rezanina <mrezanin@redhat.com>
> 
> Variable n used in tulip_idblock_crc function is only incremented but never read.
> This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.
> 
> Removing the variable to prevent the warning.
> 
> Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
> ---
>   hw/net/tulip.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/hw/net/tulip.c b/hw/net/tulip.c
> index b9e42c322a..c2b3b1bdfa 100644
> --- a/hw/net/tulip.c
> +++ b/hw/net/tulip.c
> @@ -870,11 +870,10 @@ static const MemoryRegionOps tulip_ops = {
>   
>   static void tulip_idblock_crc(TULIPState *s, uint16_t *srom)
>   {
> -    int word, n;
> +    int word;
>       int bit;
>       unsigned char bitval, crc;
>       const int len = 9;
> -    n = 0;
>       crc = -1;
>   
>       for (word = 0; word < len; word++) {
> @@ -887,7 +886,6 @@ static void tulip_idblock_crc(TULIPState *s, uint16_t *srom)
>                   srom[len - 1] = (srom[len - 1] & 0xff00) | (unsigned short)crc;
>                   break;
>               }
> -            n++;
>               bitval = ((srom[word] >> bit) & 1) ^ ((crc >> 7) & 1);
>               crc = crc << 1;
>               if (bitval == 1) {

Reviewed-by: Thomas Huth <thuth@redhat.com>

[PATCH 3/4] qemu-img: remove unused variable

[mrezanin]

From: Miroslav Rezanina <mrezanin@redhat.com>

Variable block_count used in img_dd function is only incremented but never read.
This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.

Removing the variable to prevent the warning.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 qemu-img.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index a3b64c88af..a9b3a8103c 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -4922,7 +4922,7 @@ static int img_dd(int argc, char **argv)
     const char *out_fmt = "raw";
     const char *fmt = NULL;
     int64_t size = 0;
-    int64_t block_count = 0, out_pos, in_pos;
+    int64_t out_pos, in_pos;
     bool force_share = false;
     struct DdInfo dd = {
         .flags = 0,
@@ -5122,7 +5122,7 @@ static int img_dd(int argc, char **argv)
 
     in.buf = g_new(uint8_t, in.bsz);
 
-    for (out_pos = 0; in_pos < size; block_count++) {
+    for (out_pos = 0; in_pos < size; ) {
         int bytes = (in_pos + in.bsz > size) ? size - in_pos : in.bsz;
 
         ret = blk_pread(blk1, in_pos, bytes, in.buf, 0);
-- 
2.31.1

Re: [PATCH 3/4] qemu-img: remove unused variable

[Thomas Huth]

On 09/11/2022 16.57, mrezanin@redhat.com wrote:
> From: Miroslav Rezanina <mrezanin@redhat.com>
> 
> Variable block_count used in img_dd function is only incremented but never read.
> This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.
> 
> Removing the variable to prevent the warning.
> 
> Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
> ---
>   qemu-img.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/qemu-img.c b/qemu-img.c
> index a3b64c88af..a9b3a8103c 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -4922,7 +4922,7 @@ static int img_dd(int argc, char **argv)
>       const char *out_fmt = "raw";
>       const char *fmt = NULL;
>       int64_t size = 0;
> -    int64_t block_count = 0, out_pos, in_pos;
> +    int64_t out_pos, in_pos;
>       bool force_share = false;
>       struct DdInfo dd = {
>           .flags = 0,
> @@ -5122,7 +5122,7 @@ static int img_dd(int argc, char **argv)
>   
>       in.buf = g_new(uint8_t, in.bsz);
>   
> -    for (out_pos = 0; in_pos < size; block_count++) {
> +    for (out_pos = 0; in_pos < size; ) {
>           int bytes = (in_pos + in.bsz > size) ? size - in_pos : in.bsz;
>   
>           ret = blk_pread(blk1, in_pos, bytes, in.buf, 0);

Reviewed-by: Thomas Huth <thuth@redhat.com>

[PATCH 4/4] host-libusb: Remove unused variable

[mrezanin]

From: Miroslav Rezanina <mrezanin@redhat.com>

Variable unconnected used in usb_host_auto_check function is only incremented
but never read as line where it is read was disabled since introducing the code.
This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.

Removing the variable and disabled code to prevent the warning.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/usb/host-libusb.c | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c
index 28f8af8941..176868d345 100644
--- a/hw/usb/host-libusb.c
+++ b/hw/usb/host-libusb.c
@@ -1837,7 +1837,6 @@ static void usb_host_auto_check(void *unused)
     struct USBAutoFilter *f;
     libusb_device **devs = NULL;
     struct libusb_device_descriptor ddesc;
-    int unconnected = 0;
     int i, n;
 
     if (usb_host_init() != 0) {
@@ -1897,9 +1896,6 @@ static void usb_host_auto_check(void *unused)
         libusb_free_device_list(devs, 1);
 
         QTAILQ_FOREACH(s, &hostdevs, next) {
-            if (s->dh == NULL) {
-                unconnected++;
-            }
             if (s->seen == 0) {
                 if (s->dh) {
                     usb_host_close(s);
@@ -1908,17 +1904,6 @@ static void usb_host_auto_check(void *unused)
             }
             s->seen = 0;
         }
-
-#if 0
-        if (unconnected == 0) {
-            /* nothing to watch */
-            if (usb_auto_timer) {
-                timer_del(usb_auto_timer);
-                trace_usb_host_auto_scan_disabled();
-            }
-            return;
-        }
-#endif
     }
 
     if (!usb_vmstate) {
-- 
2.31.1

Re: [PATCH 4/4] host-libusb: Remove unused variable

[Thomas Huth]

On 09/11/2022 16.57, mrezanin@redhat.com wrote:
> From: Miroslav Rezanina <mrezanin@redhat.com>
> 
> Variable unconnected used in usb_host_auto_check function is only incremented
> but never read as line where it is read was disabled since introducing the code.
> This causes 'Unused but set variable' warning on Clang 15.0.1 compiler.
> 
> Removing the variable and disabled code to prevent the warning.
> 
> Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
> ---
>   hw/usb/host-libusb.c | 15 ---------------
>   1 file changed, 15 deletions(-)
> 
> diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c
> index 28f8af8941..176868d345 100644
> --- a/hw/usb/host-libusb.c
> +++ b/hw/usb/host-libusb.c
> @@ -1837,7 +1837,6 @@ static void usb_host_auto_check(void *unused)
>       struct USBAutoFilter *f;
>       libusb_device **devs = NULL;
>       struct libusb_device_descriptor ddesc;
> -    int unconnected = 0;
>       int i, n;
>   
>       if (usb_host_init() != 0) {
> @@ -1897,9 +1896,6 @@ static void usb_host_auto_check(void *unused)
>           libusb_free_device_list(devs, 1);
>   
>           QTAILQ_FOREACH(s, &hostdevs, next) {
> -            if (s->dh == NULL) {
> -                unconnected++;
> -            }
>               if (s->seen == 0) {
>                   if (s->dh) {
>                       usb_host_close(s);
> @@ -1908,17 +1904,6 @@ static void usb_host_auto_check(void *unused)
>               }
>               s->seen = 0;
>           }
> -
> -#if 0
> -        if (unconnected == 0) {
> -            /* nothing to watch */
> -            if (usb_auto_timer) {
> -                timer_del(usb_auto_timer);
> -                trace_usb_host_auto_scan_disabled();
> -            }
> -            return;
> -        }
> -#endif
>       }
>   
>       if (!usb_vmstate) {

Reviewed-by: Thomas Huth <thuth@redhat.com>