tce-load -i itstool intltool gobject-introspection-dev accountsservice-dev libcanberra-dev linux-pam-dev

cd gdm-3.16.1.1

Edit configure

   X_PATH="/usr/local/bin"
   X_SERVER_PATH="/usrlocal/bin"
   X_SERVER="/usr/local/bin/X"

CC="gcc -mtune=generic -Os -pipe" CXX="g++ -mtune=generic -Os -pipe -fno-exceptions -fno-rtti"  ./configure --prefix=/usr/local --disable-static --localstatedir=/var --libexecdir=/usr/local/lib/gdm --without-systemd --with-user=tc --with-group=staff --without-console-kit --without-plymouth

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

make
sudo make install

                    GDM 3.16.1.1
                    ============

        prefix:                   /usr/local
        exec_prefix:              ${prefix}
        libdir:                   ${exec_prefix}/lib
        bindir:                   ${exec_prefix}/bin
        sbindir:                  ${exec_prefix}/sbin
        sysconfdir:               ${prefix}/etc
        sysconfsubdir:            gdm
        gdmconfdir:               ${sysconfdir}/${sysconfsubdir}
        dmconfdir:                ${prefix}/etc/dm
        localstatedir:            /var
        datadir:                  ${datarootdir}
        consolekit location:      ${libexecdir}
        gnome-settings-daemon location: ${libexecdir}
        gnome-session-check-accel location: ${libexecdir}
        source code location:     .
        compiler:                 gcc -flto -fuse-linker-plugin -mtune=generic -Os -pipe
        cflags:                   -g -O2
        Maintainer mode:          yes

        user:                     tc
        group:                    staff

        dbus-1 system.d dir:      ${prefix}/etc/dbus-1/system.d
        PAM prefix:               ${sysconfdir}
        PAM config:               none
        X server:                 /usr/local/bin/X

        TCP Wrappers support:     no
        Xinerama support:         yes
        XDMCP support:            yes
        SELinux support:          no
        ConsoleKit support:       no
        systemd support:          no
        systemd unit dir:         
        plymouth support:         no
        wayland support:          no
        Build with RBAC:          no
        Initial VT:               1
        Enable documentation:     yes