tce-load -i compiletc meson yasm gst-plugins-base-dev ffmpeg4-dev

https://gstreamer.freedesktop.org/src/gst-libav/gst-libav-1.16.2.tar.xz

cd gst-libav-1.16.2

mkdir build
cd build

CC="gcc -flto -fuse-linker-plugin -march=i486 -mtune=i686 -Os -pipe" CXX="g++ -flto -fuse-linker-plugin -march=i486 -mtune=i686 -Os -pipe -fno-exceptions -fno-rtti" meson --prefix=/usr/local --localstatedir=/var --libexecdir=/usr/local/lib --buildtype=plain -Dgtk_doc=disabled ../

ninja [0m 4.46s]
sudo ninja install