--- makefile.orig	2012-12-20 13:58:45 UTC
+++ makefile
@@ -22,19 +22,9 @@
 # THIS SOFTWARE.
 # ****************************************************************/
 
-CFLAGS = -g
-CFLAGS = -O2
-CFLAGS =
-
-CC = gcc -Wall -g -Wwrite-strings
-CC = gcc -fprofile-arcs -ftest-coverage # then gcov f1.c; cat f1.c.gcov
-CC = gcc -g -Wall -pedantic 
-CC = gcc -O4 -Wall -pedantic -fno-strict-aliasing
-
-YACC = bison -d -y
-YACC = yacc -d -S
-#YFLAGS = -d -S
-		# -S uses sprintf in yacc parser instead of sprint
+
+CC?= cc
+YACC?= yacc -d
 
 OFILES = b.o main.o parse.o proctab.o tran.o lib.o run.o lex.o