porting-to-1.0.txt: add troubleshooting section

Add note about "cannot register existing type `GstObject'" warning.

1 files changed, 16 insertions, 0 deletions

diff --git a/docs/random/porting-to-1.0.txt b/docs/random/porting-to-1.0.txt
index 08f2f9e0e..1bf4e26cc 100644
--- a/docs/random/porting-to-1.0.txt
+++ b/docs/random/porting-to-1.0.txt
@@ -738,3 +738,19 @@ CHANGES
         or even
 
           playbin uri=file:///path/to/foo.flac audio-sink=pulsesink
+
+
+=============================================================================
+  Troubleshooting
+=============================================================================
+
+ * GLib-GObject-WARNING **: cannot register existing type `GstObject'
+
+   If you get this warning, this usually means your plugin or application
+   is linked against both libgstreamer-1.0.so and libgstreamer-0.10.so.
+   Make sure you have changed all -0.10 references in your configure.ac,
+   pkg-config invocations or Makefile.am/Makefile to -1.0.
+
+   While both versions can co-exist without problems on the same system, it
+   is not possible to use both versions at the same time in the same
+   application.