GNU Modula-2 is about to go into the GCC tree (for GCC-12 onwards).
In time the front end also will be back ported to GCC-11. Releases prior to GCC-11 are still available from the gm2 git reprository and tarballs on floppsie.comp.glam.ac.uk (see the download tab).
Documentation for GNU Modula-2 on GCC-12.
Documentation for GNU Modula-2 on GCC-11.