export CFLAGS="-Os -pipe -march=armv8-a+crc -mtune=cortex-a72"
export CXXFLAGS="-Os -pipe -fno-exceptions -fno-rtti -march=armv8-a+crc -mtune=cortex-a72"

#after configure
find . -name Makefile -type f -exec sed -i 's/-g -O2//g' {} \;