Index: /trunk/src/org/openstreetmap/josm/gui/layer/OsmDataLayer.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/layer/OsmDataLayer.java	(revision 9480)
+++ /trunk/src/org/openstreetmap/josm/gui/layer/OsmDataLayer.java	(revision 9481)
@@ -746,6 +746,8 @@
             final GpxData data = toGpxData();
             final GpxLayer gpxLayer = new GpxLayer(data, tr("Converted from: {0}", getName()));
-            final String filename = getAssociatedFile().getName().replaceAll(Pattern.quote(".gpx.osm") + "$", "") + ".gpx";
-            gpxLayer.setAssociatedFile(new File(getAssociatedFile().getParentFile(), filename));
+            if (getAssociatedFile() != null) {
+                final String filename = getAssociatedFile().getName().replaceAll(Pattern.quote(".gpx.osm") + "$", "") + ".gpx";
+                gpxLayer.setAssociatedFile(new File(getAssociatedFile().getParentFile(), filename));
+            }
             Main.main.addLayer(gpxLayer);
             if (Main.pref.getBoolean("marker.makeautomarkers", true) && !data.waypoints.isEmpty()) {