diff --git a/builds/Resources/Include_Common.mk b/builds/Resources/Include_Common.mk
index 2c1bdb2..5a5dd7a 100644
--- a/builds/Resources/Include_Common.mk
+++ b/builds/Resources/Include_Common.mk
@@ -90,13 +90,13 @@ BSC_COMPILATION_FLAGS += \
 	-D PERFORMANCE_MONITORING \
 	-D RAS_HIT_TRACING \
 	-D TSO_MM \
-	-D NO_SPEC_STRAIGHT_PATH -D SPEC_RSB_FIXUP \
+	-D NO_SPEC_STRAIGHT_PATH -D SPEC_RSB_FIXUP -D NO_SPEC_STL \
 	-keep-fires -aggressive-conditions -no-warn-action-shadowing -check-assert \
 	-suppress-warnings G0020 -steps-max-intervals 10000000   \
 	-steps-warn-interval 1000000 \
 	+RTS -K128M -RTS  -show-range-conflict
 
-#	-D NO_SPEC_TRAINING -D NO_SPEC_REDIRECT -D NO_SPEC_STRAIGHT_PATH -D SPEC_RSB_FIXUP -D NO_SPEC_RSB_PUSH
+#	-D NO_SPEC_TRAINING -D NO_SPEC_REDIRECT -D NO_SPEC_STRAIGHT_PATH -D SPEC_RSB_FIXUP -D NO_SPEC_RSB_PUSH -D NO_SPEC_STL
 
 # ================================================================
 # Runs simulation executable on ELF given by EXAMPLE
diff --git a/src_Core/RISCY_OOO/procs/lib/STLPred.bsv b/src_Core/RISCY_OOO/procs/lib/STLPred.bsv
index cdcfb4e..5586de6 100644
--- a/src_Core/RISCY_OOO/procs/lib/STLPred.bsv
+++ b/src_Core/RISCY_OOO/procs/lib/STLPred.bsv
@@ -57,7 +57,11 @@ module mkSTLPred(STLPred);
     endmethod
 
     method Bool pred(Bit#(16) pc_hash);
+`ifdef NO_SPEC_STL
         return fromMaybe(minBound, ldKillMap.lookup(unpack(pc_hash))) == maxBound;
+`else
+        return True;
+`endif
     endmethod
-    
+
 endmodule
diff --git a/src_SSITH_P3/Makefile b/src_SSITH_P3/Makefile
index 88ff197..2eb32f6 100644
--- a/src_SSITH_P3/Makefile
+++ b/src_SSITH_P3/Makefile
@@ -40,6 +40,7 @@ BSC_COMPILATION_FLAGS += \
 	-D RISCV \
 	-D TSO_MM \
 	-D NO_SPEC_STRAIGHT_PATH -D SPEC_RSB_FIXUP \
+	-D NO_SPEC_STL \
 	-D INCLUDE_GDB_CONTROL \
 	-D BRVF_TRACE \
 	-D XILINX_BSCAN  -D JTAG_TAP