--- pigz-2.8/Makefile.old	2019-04-11 03:39:47.000000000 -0500
+++ pigz-2.8/Makefile	2023-10-02 01:07:29.659463951 -0500
@@ -1,6 +1,6 @@
-CC=gcc
-CFLAGS=-O3 -Wall -Wextra -Wno-unknown-pragmas -Wcast-qual
-LDFLAGS=
+CC ?= gcc
+CFLAGS ?= -O3 -Wall -Wextra -Wno-unknown-pragmas -Wcast-qual
+LDFLAGS ?=
 # CFLAGS=-O3 -Wall -Wextra -Wno-unknown-pragmas -Wcast-qual -g -fsanitize=thread
 # LDFLAGS=-g -fsanitize=thread
 # CFLAGS=-O3 -Wall -Wextra -Wno-unknown-pragmas -Wcast-qual -g -fsanitize=address