Commit a56d6cb170 for aom

commit a56d6cb170003a186c70f9e3771d04622a71ec44
Author: Wan-Teh Chang <wtc@google.com>
Date:   Fri Dec 12 11:16:28 2025 -0800

    Assert cpi->existing_fb_idx_to_show is valid index

    In av1_finalize_encoded_frame(), assert that
    cpi->existing_fb_idx_to_show is a valid index for the cm->ref_frame_map
    array.

    Hopefully this will suppress Coverity defect CID 555118:
    Improper use of negative value (NEGATIVE_RETURNS)

    Change-Id: I6e0377dd4d12c5b39e8a8b9391ea52bc80148c19

diff --git a/av1/encoder/encoder_utils.c b/av1/encoder/encoder_utils.c
index 415799e9b7..e68938561a 100644
--- a/av1/encoder/encoder_utils.c
+++ b/av1/encoder/encoder_utils.c
@@ -9,6 +9,7 @@
  * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
  */

+#include <assert.h>
 #include <string.h>

 #include "aom/aomcx.h"
@@ -1317,6 +1318,8 @@ void av1_finalize_encoded_frame(AV1_COMP *const cpi) {

   if (!cm->seq_params->reduced_still_picture_hdr &&
       encode_show_existing_frame(cm)) {
+    assert(cpi->existing_fb_idx_to_show >= 0 &&
+           cpi->existing_fb_idx_to_show < REF_FRAMES);
     RefCntBuffer *const frame_to_show =
         cm->ref_frame_map[cpi->existing_fb_idx_to_show];