[gthumb] ignore non existing extensions

[Paolo Bacchilega <paobac src gnome org>]

commit 0de99441acd004e67bbf9e53347c8144a3889ca7
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Tue Feb 16 10:42:25 2010 +0100

    ignore non existing extensions

 gthumb/gth-extensions.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gthumb/gth-extensions.c b/gthumb/gth-extensions.c
index 4f0d895..0493967 100644
--- a/gthumb/gth-extensions.c
+++ b/gthumb/gth-extensions.c
@@ -872,7 +872,8 @@ get_extension_optional_dependencies (GthExtensionManager     *manager,
 		dependencies = g_list_prepend (dependencies, extension_name);
 
 		other_description = g_hash_table_lookup (manager->priv->extensions, extension_name);
-		dependencies = g_list_concat (get_extension_optional_dependencies (manager, other_description), dependencies);
+		if (other_description != NULL)
+			dependencies = g_list_concat (get_extension_optional_dependencies (manager, other_description), dependencies);
 	}
 
 	return dependencies;