diff --git a/Makefile b/Makefile
index 0df9cf70..efc417d6 100644
--- a/Makefile
+++ b/Makefile
@@ -193,7 +193,7 @@ endif
 # header files.
 .PHONY: icg_sim_serv
 icg_sim_serv: $(ICG_EXE)
-	${TRICK_HOME}/bin/trick-ICG -s -m ${TRICK_CXXFLAGS} ${TRICK_SYSTEM_CXXFLAGS} ${TRICK_HOME}/include/trick/files_to_ICG.hh
+	${TRICK_HOME}/bin/trick-ICG -s -m -n ${TRICK_CXXFLAGS} ${TRICK_SYSTEM_CXXFLAGS} ${TRICK_HOME}/include/trick/files_to_ICG.hh
 
 # 1.1.1.4.1 Build the Interface Code Generator (ICG) executable.
 $(ICG_EXE) :
@@ -388,7 +388,7 @@ uninstall:
 # ICG all sim_services files (for testing and debugging ICG).
 # The -f flag forces io_src files to be regenerated whether or not they need to be.
 ICG: $(ICG_EXE)
-	${TRICK_HOME}/bin/trick-ICG -f -s -m ${TRICK_CXXFLAGS} ${TRICK_SYSTEM_CXXFLAGS} ${TRICK_HOME}/include/trick/files_to_ICG.hh
+	${TRICK_HOME}/bin/trick-ICG -f -s -m -n ${TRICK_CXXFLAGS} ${TRICK_SYSTEM_CXXFLAGS} ${TRICK_HOME}/include/trick/files_to_ICG.hh
 
 # This builds a tricklib share library.
 trick_lib: $(SIM_SERV_DIRS) $(UTILS_DIRS) | $(TRICK_LIB_DIR)