gstpipeline: fix failed assertion caused by seeking pipeline with NULL clock

Under certain GST_STATE_CHANGED_PAUSED_TO_PLAYING transitions, a pipeline with
a NULL clock will fail an assertion due to an unchecked call to gst_object_ref().
This is fixed by simply adding a check and only ref-ing if the clock is not NULL.

https://bugzilla.gnome.org/show_bug.cgi?id=693065

diff --git a/gst/gstpipeline.c b/gst/gstpipeline.c
index 6a603e4..51226a4 100644 (file)
--- a/gst/gstpipeline.c
+++ b/gst/gstpipeline.c
@@ -405,7 +405,10 @@ gst_pipeline_change_state (GstElement * element, GstStateChange transition)
         } else {
           GST_DEBUG_OBJECT (pipeline,
               "Don't need to update clock, using old clock.");
-          clock = gst_object_ref (cur_clock);
+          /* only try to ref if cur_clock is not NULL */
+          if (cur_clock)
+            gst_object_ref (cur_clock);
+          clock = cur_clock;
         }
 
         if (clock) {