diff --git a/Makefile b/Makefile
index 91f2f19..7f64ff1 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,8 @@ $(OUTPUT_DIR)/%: $(TDIR)/%.c
 # Specific rule for USTACK
 $(OUTPUT_DIR)/$(USTACK): $(TDIR)/$(USTACK).c
 	mkdir -p $(@D)
-	$(CC) -g $(CFLAGS) -o $@ $< -lunwind -lunwind-x86_64
+	# $(CC) -g $(CFLAGS) -o $@ $< -lunwind -lunwind-x86_64
+	$(CC) -g -O2 $(CFLAGS) -o $@ $<
 
 # $(SPID): $(TDIR)/stack-pid.c
 # 	mkdir -p $(OUTPUT_DIR)