--- a/Makefile
+++ b/Makefile
@@ -21,13 +21,12 @@
 # to change it to this:
 # CFLAGS = -Xc
 
-CFLAGS = -std=gnu99 -W -Wall -Wconversion -pedantic $(DEBUG) $(OPT)
+CFLAGS += -std=gnu99 -Wall -Wconversion -pedantic
 
 
 # The default is GCC.  On Solaris, you might put:
 # CC = /opt/SUNWspro/bin/cc
 
-CC = gcc
 
 
 # Depending on the compile flags you use, you might need to explicitly use the
@@ -42,7 +41,7 @@
 OBJS = sim4b1.o align.o misc.o sim4.init.o
 
 sim4: $(OBJS)
-	$(CC) -o SIBsim4 $(CFLAGS) $(OBJS) $(LIBS)
+	$(CC) $(CFLAGS) $(LDFLAGS) -o SIBsim4 $(OBJS) $(LIBS)
 
 clean:
 	rm -f SIBsim4 *.o