[PATCH v2] migration/block-dirty-bitmap: fix uninitialized variable warning

[Chen Qun]

A default value is provided for the variable 'bitmap_name' to avoid compiler 
warning.

The compiler show warning:
migration/block-dirty-bitmap.c:1090:13: warning: ‘bitmap_name’
may be used uninitialized in this function [-Wmaybe-uninitialized]
       g_strlcpy(s->bitmap_name, bitmap_name, sizeof(s->bitmap_name));
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Reported-by: Euler Robot <euler.ro...@huawei.com>
Signed-off-by: Chen Qun <kuhn.chen...@huawei.com>
---
Cc: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Cc: Laurent Vivier <laur...@vivier.eu>
Cc: Li Qiang <liq...@gmail.com>
---
 migration/block-dirty-bitmap.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c
index 5bef793ac0..bcb79c04ce 100644
--- a/migration/block-dirty-bitmap.c
+++ b/migration/block-dirty-bitmap.c
@@ -1064,15 +1064,13 @@ static int dirty_bitmap_load_header(QEMUFile *f, 
DBMLoadState *s,
     assert(nothing || s->cancelled || !!alias_map == !!bitmap_alias_map);
 
     if (s->flags & DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME) {
-        const char *bitmap_name;
-
         if (!qemu_get_counted_string(f, s->bitmap_alias)) {
             error_report("Unable to read bitmap alias string");
             return -EINVAL;
         }
 
-        if (!s->cancelled) {
-            if (bitmap_alias_map) {
+        const char *bitmap_name = s->bitmap_alias;
+        if (!s->cancelled && bitmap_alias_map) {
                 bitmap_name = g_hash_table_lookup(bitmap_alias_map,
                                                   s->bitmap_alias);
                 if (!bitmap_name) {
@@ -1081,9 +1079,6 @@ static int dirty_bitmap_load_header(QEMUFile *f, 
DBMLoadState *s,
                                  s->bs->node_name, s->node_alias);
                     cancel_incoming_locked(s);
                 }
-            } else {
-                bitmap_name = s->bitmap_alias;
-            }
         }
 
         if (!s->cancelled) {
-- 
2.23.0