In this talk, the speaker discusses the Rust GCC project, which is a full implementation of Rust on top of the GNU toolchain. They explain the motivation behind the project, such as upstreaming it to mainline GCC and helping drive the specification effort of the Rust language. The speaker goes on to describe the various components of the compiler, such as the parser and intermediate representation, and talks about the project's workflow, community, and future goals. They also mention the tooling around GCC RS, including a test suite, website, and cargo subcommand. The talk concludes with a Q&A session.