diff --git a/common.mk b/common.mk
index b6519df..ce5f845 100644
--- a/common.mk
+++ b/common.mk
@@ -71,7 +71,7 @@ verilog: $(sim_vsrcs)
 # helper rules to run simulator
 #########################################################################################
 run-binary: $(sim)
-	$(sim) $(PERMISSIVEON) $(SIM_FLAGS) $(PERMISSIVEOFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out
+	$(sim) $(PERMISSIVE_ON) $(SIM_FLAGS) $(PERMISSIVE_OFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out
 
 #########################################################################################
 # run assembly/benchmarks rules
@@ -81,10 +81,10 @@ $(output_dir)/%: $(RISCV)/riscv64-unknown-elf/share/riscv-tests/isa/%
 	ln -sf $< $@
 
 $(output_dir)/%.run: $(output_dir)/% $(sim)
-	$(sim) +max-cycles=$(timeout_cycles) $< && touch $@
+	$(sim) $(PERMISSIVE_ON) +max-cycles=$(timeout_cycles) $(PERMISSIVE_OFF) $< && touch $@
 
 $(output_dir)/%.out: $(output_dir)/% $(sim)
-	$(sim) $(PERMISSIVEON) +verbose +max-cycles=$(timeout_cycles) $(PERMISSIVEOFF) $< 3>&1 1>&2 2>&3 | spike-dasm > $@
+	$(sim) $(PERMISSIVE_ON) +verbose +max-cycles=$(timeout_cycles) $(PERMISSIVE_OFF) $< 3>&1 1>&2 2>&3 | spike-dasm > $@
 
 #########################################################################################
 # include build/project specific makefrags made from the generator
diff --git a/sims/verisim/Makefile b/sims/verisim/Makefile
index 9264b43..655d67c 100644
--- a/sims/verisim/Makefile
+++ b/sims/verisim/Makefile
@@ -25,8 +25,8 @@ sim_prefix = simulator
 sim = $(sim_dir)/$(sim_prefix)-$(MODEL_PACKAGE)-$(CONFIG)
 sim_debug = $(sim_dir)/$(sim_prefix)-$(MODEL_PACKAGE)-$(CONFIG)-debug
 
-PERMISSIVEON=
-PERMISSIVEOFF=
+PERMISSIVE_ON=
+PERMISSIVE_OFF=
 
 .PHONY: default debug
 default: $(sim)
diff --git a/sims/vsim/Makefile b/sims/vsim/Makefile
index a9edcdc..d34fb5e 100644
--- a/sims/vsim/Makefile
+++ b/sims/vsim/Makefile
@@ -25,8 +25,8 @@ sim_prefix = simv
 sim = $(sim_dir)/$(sim_prefix)-$(MODEL_PACKAGE)-$(CONFIG)
 sim_debug = $(sim_dir)/$(sim_prefix)-$(MODEL_PACKAGE)-$(CONFIG)-debug
 
-PERMISSIVEON=+permissive
-PERMISSIVEOFF=+permissive-off
+PERMISSIVE_ON=+permissive
+PERMISSIVE_OFF=+permissive-off
 
 .PHONY: default debug
 default: $(sim)
@@ -90,13 +90,13 @@ $(sim_debug) : $(sim_vsrcs) $(sim_dotf)
 # helper rules to run simulator with debug
 #########################################################################################
 run-binary-debug: $(sim_debug)
-	$(sim_debug) $(PERMISSIVEON) $(SIM_FLAGS) +vcdplusfile=$(sim_out_name).vpd $(PERMISSIVEOFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out
+	$(sim_debug) $(PERMISSIVE_ON) $(SIM_FLAGS) +vcdplusfile=$(sim_out_name).vpd $(PERMISSIVE_OFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out
 
 #########################################################################################
 # create a vcs vpd rule
 #########################################################################################
 $(output_dir)/%.vpd: $(output_dir)/% $(sim_debug)
-	$(sim_debug) +vcdplusfile=$@ +max-cycles=$(timeout_cycles) $<
+	$(sim_debug) $(PERMISSIVE_ON) +vcdplusfile=$@ +max-cycles=$(timeout_cycles) $(PERMISSIVE_OFF) $<
 
 #########################################################################################
 # general cleanup rule