Index: trunk/src_plugins/io_hyp/write.c
===================================================================
--- trunk/src_plugins/io_hyp/write.c	(revision 23029)
+++ trunk/src_plugins/io_hyp/write.c	(revision 23030)
@@ -86,7 +86,7 @@
 			name = grp->name;
 		for(n = 0; n < wr->pcb->LayerGroups.len; n++) {
 			pcb_layergrp_t *g = &wr->pcb->LayerGroups.grp[n];
-			if ((g != grp) && (strcmp(g->name, name) == 0)) {
+			if ((g != grp) && (g->name != NULL) && (strcmp(g->name, name) == 0)) {
 				dup = 1;
 				break;
 			}