diff mbox series

[v2,5/5] migration: fix uninitialized variable warning in migrate_send_rp_req_pages()

Message ID 20201111142203.2359370-6-kuhn.chenqun@huawei.com
State New
Headers show
Series fix uninitialized variable warning | expand

Commit Message

Chen Qun Nov. 11, 2020, 2:22 p.m. UTC
After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify
 that the statements in the macro must be executed. As a result, some variables
 assignment statements in the macro may be considered as unexecuted by the compiler.

When the -Wmaybe-uninitialized capability is enabled on GCC9,the compiler showed warning:
migration/migration.c: In function ‘migrate_send_rp_req_pages’:
migration/migration.c:384:8: warning: ‘received’ may be used uninitialized in this function [-Wmaybe-uninitialized]
 384 |     if (received) {
     |        ^

Add a default value for 'received' to prevented the warning.

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
---
 migration/migration.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Dr. David Alan Gilbert (git) Nov. 12, 2020, 2:49 p.m. UTC | #1
* Chen Qun (kuhn.chenqun@huawei.com) wrote:
> After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify
>  that the statements in the macro must be executed. As a result, some variables
>  assignment statements in the macro may be considered as unexecuted by the compiler.
> 
> When the -Wmaybe-uninitialized capability is enabled on GCC9,the compiler showed warning:
> migration/migration.c: In function ‘migrate_send_rp_req_pages’:
> migration/migration.c:384:8: warning: ‘received’ may be used uninitialized in this function [-Wmaybe-uninitialized]
>  384 |     if (received) {
>      |        ^
> 
> Add a default value for 'received' to prevented the warning.
> 
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Queuing this one via migration

> ---
> Cc: Juan Quintela <quintela@redhat.com>
> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> ---
>  migration/migration.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 9bb4fee5ac..de90486a61 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -361,7 +361,7 @@ int migrate_send_rp_req_pages(MigrationIncomingState *mis,
>                                RAMBlock *rb, ram_addr_t start, uint64_t haddr)
>  {
>      void *aligned = (void *)(uintptr_t)(haddr & (-qemu_ram_pagesize(rb)));
> -    bool received;
> +    bool received = false;
>  
>      WITH_QEMU_LOCK_GUARD(&mis->page_request_mutex) {
>          received = ramblock_recv_bitmap_test_byte_offset(rb, start);
> -- 
> 2.27.0
> 
>
diff mbox series

Patch

diff --git a/migration/migration.c b/migration/migration.c
index 9bb4fee5ac..de90486a61 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -361,7 +361,7 @@  int migrate_send_rp_req_pages(MigrationIncomingState *mis,
                               RAMBlock *rb, ram_addr_t start, uint64_t haddr)
 {
     void *aligned = (void *)(uintptr_t)(haddr & (-qemu_ram_pagesize(rb)));
-    bool received;
+    bool received = false;
 
     WITH_QEMU_LOCK_GUARD(&mis->page_request_mutex) {
         received = ramblock_recv_bitmap_test_byte_offset(rb, start);