diff --git a/sims/vcs/vcs.mk b/sims/vcs/vcs.mk
index 31784ad9..f816f102 100644
--- a/sims/vcs/vcs.mk
+++ b/sims/vcs/vcs.mk
@@ -57,5 +57,5 @@ VCS_PREPROC_DEFINES = \
 	+define+VCS
 
 ifndef USE_VPD
-PREPROC_DEFINES += +define+FSDB
+VCS_PREPROC_DEFINES += +define+FSDB
 endif
diff --git a/sims/verilator/Makefile b/sims/verilator/Makefile
index 9e22821d..11b80331 100644
--- a/sims/verilator/Makefile
+++ b/sims/verilator/Makefile
@@ -96,8 +96,7 @@ USE_FST ?= 0
 TRACING_OPTS := $(if $(filter $(USE_FST),0),\
 	                  --trace,--trace-fst --trace-threads 1)
 # TODO: consider renaming +vcdfile in TestDriver.v to +waveformfile (or similar)
-WAVEFORM_FLAG := +vcdfile=$(sim_out_name).$(if $(filter $(USE_FST),0),\
-	                  vcd,fst)
+WAVEFORM_FLAG := +vcdfile=$(sim_out_name).$(if $(filter $(USE_FST),0),vcd,fst)
 
 #----------------------------------------------------------------------------------------
 # verilation configuration/optimization