======== How to build ash/hexdump/xzcat for aarch64 ======== 
#How to get ash.config/hexdump.cofig/xzcat.config
#ARCH=arm64 CROSS_COMPILE=aarch64-linux- make allnoconfig
#ARCH=arm64 CROSS_COMPILE=aarch64-linux- make menuconfig 
#----> enable static build
#----> enable xzcat
#get aarch64_xzcat.config

tar xf busybox-1.32.0.tar.bz2
cd busybox-1.32.0
copy aarch64_xzcat.config as .config
ARCH=arm64 CROSS_COMPILE=aarch64-linux- make 
rename ./busybox to xzcat



======== How to build ash/hexdump/xzcat for x86_64 ==========
#How to get ash.config/hexdump.cofig/xzcat.config
#make allnoconfig
#make menuconfig 
#----> enable static build
#----> enable xzcat
#get x86_64_xzcat.config


tar xf busybox-1.32.0.tar.bz2
cd busybox-1.32.0
copy x86_64_xzcat.config as .config
modify Makefile
CC		= gcc -specs "/usr/local/musl/lib/musl-gcc.specs"
MODFLAGS	= -DMODULE -specs "/usr/local/musl/lib/musl-gcc.specs"
make
rename ./busybox to xzcat