[sigsev_251]

- Though freeware and not foss, there is also pellesc over at Windows land, with almost full C23 support.

- For small 8 bit systems, SDCC is an excellent choice, supporting even C23 features! Also its lead maintainer is a committee member with really useful contributions to the standard.

- I have heard the RiscOS compiler is pretty cool and supports modern standards. That one uses the Norcroft frontend.

I agree with you in that we need a production level C compiler written in C. Though that is not a simple task and the C community nowadays prefers to engage on infighting over pedantic issues or rust rather than working together. A simple example of this is the lack of a modern library ecosystem, while everyone and their mother has their own custom build system. Even though C is sold as a performant language, there isn't a single parallelism library like OneTBB, Kokkos or HPX over at C++. Don't get me started on vendors not offering good standard support (Microsoft, macos-libc, OpenBSD libc)...

One correction though, cparser uses libfirm as a backend, not qbe. Also the author of chibicc has stopped writing that book AFAIK.

Bonus non-c based entries: - The zig community is working on arocc. Judging by the awesomeness of zig cc, these are really good news. - Nvidia offers their EDG based nvc with OpenACC support for free these days, which is cool.

Edit: formatting