I am working on this![0] But this is actually a herculean task, I've been chipping at it for weeks and even trying to cheat somewhat by translating mrustc from C++ to C89. If anyone has ideas/cheaper ways to run it I would like to know.

In the meantime, months ago I achieved bootstrap of TCC (then GCC 4.6) via the same path as the live-bootstrap project but replacing the Scheme part with a C compiler in Ben Lynn's Haskell dialect.[1] This was a project I wish I had time to do years ago[2] but never had the time or motivation for, and the type of things agents can do well now (they couldn't write good Haskell a year ago).

[0] https://github.com/siraben/mrustc/tree/siraben/cmrustc

[1] https://github.com/siraben/blynn-bootstrap

[2] https://logs.guix.gnu.org/bootstrappable/2021-05-26.log#1438...