Index: fnc_layer_setup.c
===================================================================
--- fnc_layer_setup.c	(revision 33073)
+++ fnc_layer_setup.c	(revision 33074)
@@ -120,7 +120,7 @@
 							lys++;
 						}
 						lyt = pcb_layer_type_str2bit(lys);
-						if ((lyt == -1) || ((lyt & lyt_allow) != lyt)) {
+						if ((lyt == 0) || ((lyt & lyt_allow) != lyt)) {
 							rnd_message(RND_MSG_ERROR, "layer_setup() compilation error: invalid netmargin value '%s'\n", val);
 							return -1;
 						}