There was also "boringcc"

https://gcc.gnu.org/wiki/boringcc

As a boring platform for the portable parts of boring crypto software, I'd like to see a free C compiler that clearly defines, and permanently commits to, carefully designed semantics for everything that's labeled "undefined" or "unspecified" or implementation-defined" in the C "standard" (DJ Bernstein)

And yeah I feel this:

The only thing stopping gcc from becoming the desired boringcc is to find the people willing to do the work.

(Because OSH has shopt --set strict:all, which is "boring bash". Not many people understand the corners well enough to disallow them - https://oils.pub/ )

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And Proposal for a Friendly Dialect of C (2014)

https://blog.regehr.org/archives/1180