diff --git a/ext/aalib/gstaasink.c b/ext/aalib/gstaasink.c
index 647ff316e4..98df1afeea 100644
--- a/ext/aalib/gstaasink.c
+++ b/ext/aalib/gstaasink.c
@@ -349,7 +349,7 @@ gst_aasink_propose_allocation (GstBaseSink * bsink, GstQuery * query)
   gst_query_add_allocation_pool (query, NULL, size, 2, 0);
 
   /* we support various metadata */
-  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, 0);
+  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);
 
   return TRUE;
 
diff --git a/ext/jpeg/gstjpegenc.c b/ext/jpeg/gstjpegenc.c
index 8ba8042b8e..e9173ff9e4 100644
--- a/ext/jpeg/gstjpegenc.c
+++ b/ext/jpeg/gstjpegenc.c
@@ -533,7 +533,7 @@ invalid_frame:
 static gboolean
 gst_jpegenc_propose_allocation (GstVideoEncoder * encoder, GstQuery * query)
 {
-  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, 0);
+  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);
 
   return GST_VIDEO_ENCODER_CLASS (parent_class)->propose_allocation (encoder,
       query);
diff --git a/ext/libpng/gstpngenc.c b/ext/libpng/gstpngenc.c
index 96dbbc5c0a..d13fa65877 100644
--- a/ext/libpng/gstpngenc.c
+++ b/ext/libpng/gstpngenc.c
@@ -371,7 +371,7 @@ longjmp_fail:
 static gboolean
 gst_pngenc_propose_allocation (GstVideoEncoder * encoder, GstQuery * query)
 {
-  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, 0);
+  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);
 
   return GST_VIDEO_ENCODER_CLASS (parent_class)->propose_allocation (encoder,
       query);
diff --git a/sys/v4l2/gstv4l2sink.c b/sys/v4l2/gstv4l2sink.c
index b368d9af95..a01e5fbb5c 100644
--- a/sys/v4l2/gstv4l2sink.c
+++ b/sys/v4l2/gstv4l2sink.c
@@ -653,8 +653,8 @@ gst_v4l2sink_propose_allocation (GstBaseSink * bsink, GstQuery * query)
   gst_query_add_allocation_pool (query, pool, size, 2, 0);
 
   /* we also support various metadata */
-  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, 0);
-  gst_query_add_allocation_meta (query, GST_VIDEO_CROP_META_API_TYPE, 0);
+  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);
+  gst_query_add_allocation_meta (query, GST_VIDEO_CROP_META_API_TYPE, NULL);
 
   if (pool)
     gst_object_unref (pool);