tce-load -i compiletc

wget https://ftp.gnu.org/gnu/gsl/gsl-2.7.1.tar.gz

cd gsl-2.7.1

CC="gcc -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe" CXX="g++ -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -fno-exceptions -fno-rtti" ./configure --prefix=/usr/local -disable-static --localstatedir=/var

[flto fails]

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

make [6m 49.14s]
sudo make install