--- a/Makefile
+++ b/Makefile
@@ -14,13 +14,13 @@
 SRCS = athcool.c scanpci.c
 OBJS = $(SRCS:.c=.o)
 
-CC	= gcc
+CC	?= gcc
 RM	= rm -f
-CFLAGS	= -O2 -Wall
-DEFS    = -I. -I$(includedir) -DPACKAGE=\"$(PACKAGE)\" -DVERSION=\"$(VERSION)\"
+CFLAGS	+= -Wall
+DEFS    = -I. -DPACKAGE=\"$(PACKAGE)\" -DVERSION=\"$(VERSION)\"
 #DEFS   += -DENABLE_FORCEID=1
 #DEFS   += -DDISABLE_WRITE_REG=1
-LIBS	= -lpci
+LIBS	= -lpci -lz
 
 ### rules ###
 
@@ -30,13 +30,13 @@
 all: $(PACKAGE)
 
 $(PACKAGE): $(OBJS)
-	$(CC) $(CFLAGS) $(OBJS) $(LIBS) -o $@
+	$(CC) $(CFLAGS) $(OBJS) $(LIBS) -o $@ $(LDFLAGS)
 
 install: install-program install-man # install-script
 
 install-program:
 	[ -d $(sbindir) ] || install -m 755 -d $(sbindir)
-	install -s $(PACKAGE) $(sbindir)
+	install $(PACKAGE) $(sbindir)
 
 install-man:
 	[ -d $(mandir)/man8 ] || install -m 755 -d $(mandir)/man8