diff --git a/libavfilter/vf_v360.c b/libavfilter/vf_v360.c
index e74509e6f2..26024c1208 100644
--- a/libavfilter/vf_v360.c
+++ b/libavfilter/vf_v360.c
@@ -768,6 +768,8 @@ static void cube_to_xyz(const V360Context *s,
         l_y = -vf;
         l_z =  1.f;
         break;
+    default:
+        av_assert0(0);
     }
 
     vec[0] = l_x;