You won’t get around fees paid in the certified compiler world. If you want someone to sign, stamp and deliver paperwork proving that a compiler upholds a stand

You won’t get around fees paid in the certified compiler world. If you want someone to sign, stamp and deliver paperwork proving that a compiler upholds a standard and likely also take liability for it, you’ll need to pay. Few organizations will take on liability for free. But you can get pretty close, at least in some spaces. Self-certification is always an option. Aerospace will be harder, automotive is annoying but feasible. Ferrocene for one is entirely 100% compatible with the equivalent rust compiler, in fact it is the rust compiler built, qualify-tested, packages and delivered without any significant (1) patches. As such, it’s entirely feasible to use “I’ll just use open source rustc” as an escape hatch. Not a pretty one, self certification is quite a bit of effort, but a bounded one. There’s no magic in what we did, most of it is legwork. We even open sourced the spec that the certification is based on, so you’ll have to do less legwork than we did. This has in fact been a design goal and a requirement of our early customers. I can’t speak to Adacores plans regarding upstream compatibility, I have no insight other than their public statements and they’ve been silent on that matter. (1) a few lines, mostly target support for stuff rustc doesn’t offer in tree Disclosure: I’m one of the founders of Ferrous.