tce-load -i compiletc meson glib2-dev libsigc++3-dev

wget https://download.gnome.org/sources/glibmm/2.68/glibmm-2.68.0.tar.xz

cd glibmm-2.66.0

mkdir build-lib
cd build-lib

CC="gcc -flto -mtune=generic -Os -pipe" CXX="g++ -flto -mtune=generic -Os -pipe -DNDEBUG" meson --prefix=/usr/local --localstatedir=/var --buildtype=plain -Dbuild-documentation=false -Dbuild-examples=false

ninja [2m 22.67s]
sudo ninja install

glibmm 2.66.0

         Maintainer mode: if-git-build (false)
       Compiler warnings: min
    Build deprecated API: true
Build HTML documentation: false
  Build example programs: false
Directories:
                  prefix: /usr/local
              includedir: /usr/local/include
        includeglibmmdir: /usr/local/include/glibmm-2.4
         includegiommdir: /usr/local/include/giomm-2.4
                  libdir: /usr/local/lib
         glibmmconfigdir: /usr/local/lib/glibmm-2.4/include
          giommconfigdir: /usr/local/lib/giomm-2.4/include
              gmmprocdir: /usr/local/lib/glibmm-2.4/proc
            pkgconfigdir: /usr/local/lib/pkgconfig
                 datadir: /usr/local/share
                  docdir: /usr/local/share/doc/glibmm-2.4
              devhelpdir: /usr/local/share/devhelp/books/glibmm-2.4