diff --git a/block.c b/block.c
index a307c151a8..7f0003d8ac 100644
--- a/block.c
+++ b/block.c
@@ -3001,7 +3001,8 @@ static BdrvChild *bdrv_attach_child_common(BlockDriverState *child_bs,
                                            BdrvChildRole child_role,
                                            uint64_t perm, uint64_t shared_perm,
                                            void *opaque,
-                                           Transaction *tran, Error **errp)
+                                           Transaction *transaction,
+                                           Error **errp)
 {
     BdrvChild *new_child;
     AioContext *parent_ctx, *new_child_ctx;
@@ -3088,7 +3089,7 @@ static BdrvChild *bdrv_attach_child_common(BlockDriverState *child_bs,
         .old_parent_ctx = parent_ctx,
         .old_child_ctx = child_ctx,
     };
-    tran_add(tran, &bdrv_attach_child_common_drv, s);
+    tran_add(transaction, &bdrv_attach_child_common_drv, s);
 
     if (new_child_ctx != child_ctx) {
         aio_context_release(new_child_ctx);
@@ -6073,12 +6074,12 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
     QLIST_FOREACH(drv, &bdrv_drivers, list) {
         if (drv->format_name) {
             bool found = false;
-            int i = count;
 
             if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, read_only)) {
                 continue;
             }
 
+            i = count;
             while (formats && i && !found) {
                 found = !strcmp(formats[--i], drv->format_name);
             }
diff --git a/block/rbd.c b/block/rbd.c
index 978671411e..472ca05cba 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -1290,7 +1290,7 @@ static int coroutine_fn qemu_rbd_start_co(BlockDriverState *bs,
          * operations that exceed the current size.
          */
         if (offset + bytes > s->image_size) {
-            int r = qemu_rbd_resize(bs, offset + bytes);
+            r = qemu_rbd_resize(bs, offset + bytes);
             if (r < 0) {
                 return r;
             }
diff --git a/block/stream.c b/block/stream.c
index e522bbdec5..007253880b 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -282,7 +282,6 @@ void stream_start(const char *job_id, BlockDriverState *bs,
     /* Make sure that the image is opened in read-write mode */
     bs_read_only = bdrv_is_read_only(bs);
     if (bs_read_only) {
-        int ret;
         /* Hold the chain during reopen */
         if (bdrv_freeze_backing_chain(bs, above_base, errp) < 0) {
             return;
diff --git a/block/vvfat.c b/block/vvfat.c
index 0ddc91fc09..d7425ee602 100644
--- a/block/vvfat.c
+++ b/block/vvfat.c
@@ -777,7 +777,6 @@ static int read_directory(BDRVVVFATState* s, int mapping_index)
     while((entry=readdir(dir))) {
         unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
         char* buffer;
-        direntry_t* direntry;
         struct stat st;
         int is_dot=!strcmp(entry->d_name,".");
         int is_dotdot=!strcmp(entry->d_name,"..");
@@ -857,7 +856,7 @@ static int read_directory(BDRVVVFATState* s, int mapping_index)
 
     /* fill with zeroes up to the end of the cluster */
     while(s->directory.next%(0x10*s->sectors_per_cluster)) {
-        direntry_t* direntry=array_get_next(&(s->directory));
+        direntry = array_get_next(&(s->directory));
         memset(direntry,0,sizeof(direntry_t));
     }
 
@@ -1962,24 +1961,24 @@ get_cluster_count_for_direntry(BDRVVVFATState* s, direntry_t* direntry, const ch
                  * This is horribly inefficient, but that is okay, since
                  * it is rarely executed, if at all.
                  */
-                int64_t offset = cluster2sector(s, cluster_num);
+                int64_t offs = cluster2sector(s, cluster_num);
 
                 vvfat_close_current_file(s);
                 for (i = 0; i < s->sectors_per_cluster; i++) {
                     int res;
 
                     res = bdrv_is_allocated(s->qcow->bs,
-                                            (offset + i) * BDRV_SECTOR_SIZE,
+                                            (offs + i) * BDRV_SECTOR_SIZE,
                                             BDRV_SECTOR_SIZE, NULL);
                     if (res < 0) {
                         return -1;
                     }
                     if (!res) {
-                        res = vvfat_read(s->bs, offset, s->cluster_buffer, 1);
+                        res = vvfat_read(s->bs, offs, s->cluster_buffer, 1);
                         if (res) {
                             return -1;
                         }
-                        res = bdrv_co_pwrite(s->qcow, offset * BDRV_SECTOR_SIZE,
+                        res = bdrv_co_pwrite(s->qcow, offs * BDRV_SECTOR_SIZE,
                                              BDRV_SECTOR_SIZE, s->cluster_buffer,
                                              0);
                         if (res < 0) {
@@ -2467,8 +2466,9 @@ commit_direntries(BDRVVVFATState* s, int dir_index, int parent_mapping_index)
 
     for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) {
         direntry_t *first_direntry;
-        void* direntry = array_get(&(s->directory), current_dir_index);
-        int ret = vvfat_read(s->bs, cluster2sector(s, c), direntry,
+
+        direntry = array_get(&(s->directory), current_dir_index);
+        ret = vvfat_read(s->bs, cluster2sector(s, c), (uint8_t *)direntry,
                 s->sectors_per_cluster);
         if (ret)
             return ret;
@@ -2690,12 +2690,12 @@ static int handle_renames_and_mkdirs(BDRVVVFATState* s)
                 direntry_t* direntry = array_get(&(s->directory),
                         mapping->info.dir.first_dir_index);
                 uint32_t c = mapping->begin;
-                int i = 0;
+                int j = 0;
 
                 /* recurse */
                 while (!fat_eof(s, c)) {
                     do {
-                        direntry_t* d = direntry + i;
+                        direntry_t* d = direntry + j;
 
                         if (is_file(d) || (is_directory(d) && !is_dot(d))) {
                             int l;
@@ -2716,8 +2716,8 @@ static int handle_renames_and_mkdirs(BDRVVVFATState* s)
 
                             schedule_rename(s, m->begin, new_path);
                         }
-                        i++;
-                    } while((i % (0x10 * s->sectors_per_cluster)) != 0);
+                        j++;
+                    } while((j % (0x10 * s->sectors_per_cluster)) != 0);
                     c = fat_get(s, c);
                 }
             }
@@ -2804,16 +2804,16 @@ static int coroutine_fn GRAPH_RDLOCK handle_commits(BDRVVVFATState* s)
             int begin = commit->param.new_file.first_cluster;
             mapping_t* mapping = find_mapping_for_cluster(s, begin);
             direntry_t* entry;
-            int i;
+            int j;
 
             /* find direntry */
-            for (i = 0; i < s->directory.next; i++) {
-                entry = array_get(&(s->directory), i);
+            for (j = 0; j < s->directory.next; j++) {
+                entry = array_get(&(s->directory), j);
                 if (is_file(entry) && begin_of_direntry(entry) == begin)
                     break;
             }
 
-            if (i >= s->directory.next) {
+            if (j >= s->directory.next) {
                 fail = -6;
                 continue;
             }
@@ -2833,7 +2833,7 @@ static int coroutine_fn GRAPH_RDLOCK handle_commits(BDRVVVFATState* s)
             mapping->mode = MODE_NORMAL;
             mapping->info.file.offset = 0;
 
-            if (commit_one_file(s, i, 0))
+            if (commit_one_file(s, j, 0))
                 fail = -7;
 
             break;
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 3906b9058b..a07cd7eb5d 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -369,7 +369,7 @@ static void xen_block_get_vdev(Object *obj, Visitor *v, const char *name,
     case XEN_BLOCK_VDEV_TYPE_XVD:
     case XEN_BLOCK_VDEV_TYPE_HD:
     case XEN_BLOCK_VDEV_TYPE_SD: {
-        char *name = disk_to_vbd_name(vdev->disk);
+        char *vbd_name = disk_to_vbd_name(vdev->disk);
 
         str = g_strdup_printf("%s%s%lu",
                               (vdev->type == XEN_BLOCK_VDEV_TYPE_XVD) ?
@@ -377,8 +377,8 @@ static void xen_block_get_vdev(Object *obj, Visitor *v, const char *name,
                               (vdev->type == XEN_BLOCK_VDEV_TYPE_HD) ?
                               "hd" :
                               "sd",
-                              name, vdev->partition);
-        g_free(name);
+                              vbd_name, vdev->partition);
+        g_free(vbd_name);
         break;
     }
     default:
