tce-load -i compiletc libsigc++-dev glib2-dev libxslt-dev libxml2-bin perl5

wget https://ftp.acc.umu.se/pub/GNOME/sources/glibmm/2.64/glibmm-2.64.2.tar.xz

cd glibmm-2.64.2

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

[-fno-exceptions fails]

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

make [16m 2.76s]
sudo make install