diff --git a/util/int/switch/proto.make b/util/int/switch/proto.make
index b211484f1..e478b5965 100644
--- a/util/int/switch/proto.make
+++ b/util/int/switch/proto.make
@@ -4,7 +4,7 @@
 
 SRC_DIR = $(SRC_HOME)/util/int/switch
 IP_SPEC =	$(SRC_HOME)/etc/ip_spec.t
-UCFLAGS =	-I$(UTIL_HOME)/h $(COPTIONS)
+UCFLAGS =	-I$(UTIL_HOME)/h $(UCOPTIONS)
 ULDFLAGS =	$(ULDOPTIONS)
 LINTFLAGS =	-I$(UTIL_HOME)/h $(LINTOPTIONS)