migration: fix warning for source_return_path_thread

max_len is not necessary, while it brings a warning during compilation
when specify "-Wstack-usage=1000000". Replacing using sizeof().

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1457503932-31763-1-git-send-email-peterx@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>

diff --git a/migration/migration.c b/migration/migration.c
index 7d13377b8ef0c0cc8dde3510d8dcf68c2abf04ac..a85815973ab9ef2e0fdc3a9655ff4ade61360e81 100644 (file)
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1269,8 +1269,7 @@ static void *source_return_path_thread(void *opaque)
     MigrationState *ms = opaque;
     QEMUFile *rp = ms->rp_state.from_dst_file;
     uint16_t header_len, header_type;
-    const int max_len = 512;
-    uint8_t buf[max_len];
+    uint8_t buf[512];
     uint32_t tmp32, sibling_error;
     ram_addr_t start = 0; /* =0 to silence warning */
     size_t  len = 0, expected_len;
@@ -1293,7 +1292,7 @@ static void *source_return_path_thread(void *opaque)
 
         if ((rp_cmd_args[header_type].len != -1 &&
             header_len != rp_cmd_args[header_type].len) ||
-            header_len > max_len) {
+            header_len > sizeof(buf)) {
             error_report("RP: Received '%s' message (0x%04x) with"
                     "incorrect length %d expecting %zu",
                     rp_cmd_args[header_type].name, header_type, header_len,