--- apngdis-2.9-src/Makefile
+++ apngdis-2.9-src/Makefile
@@ -1,11 +1,10 @@
 PACKAGE    = apngdis
-CC         = gcc
-CFLAGS     = -Wall -pedantic
-CFLAGS_OPT = -O2
-LIBS       = -lstdc++ -lm -lpng -lz
+CC         ?= gcc
+CFLAGS     += -Wall -pedantic
+LIBS       = -lstdc++ -lm -lpng
 
 all :
-	$(CC) $(CFLAGS) $(CFLAGS_OPT) -o $(PACKAGE) $(PACKAGE).cpp -s $(LIBS)
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $(PACKAGE) $(PACKAGE).cpp $(LIBS)
 
 .PHONY : clean