$OpenBSD: patch-Makefile,v 1.2 2018/06/09 18:38:18 bket Exp $
Index: Makefile
--- Makefile.orig
+++ Makefile
@@ -1,8 +1,8 @@
 CC = gcc
 CXX = g++
 
-CFLAGS = -W -Wall -Wextra -ansi -pedantic -lm -O2 -Wno-unused-function
-CXXFLAGS = -W -Wall -Wextra -ansi -pedantic -O2
+CFLAGS = -W -Wall -Wextra -ansi -pedantic -lm $(COPTFLAGS) -Wno-unused-function
+CXXFLAGS = -W -Wall -Wextra -ansi -pedantic $(COPTFLAGS)
 
 ZOPFLILIB_SRC = src/zopfli/blocksplitter.c src/zopfli/cache.c\
                 src/zopfli/deflate.c src/zopfli/gzip_container.c\
