For a good while this process was just straight up not possible for C and C++, until someone put in a lot of effort to recreate the bootstrap process for reasons of reproducible builds (and it's still a long and complicated process I think only a few people have done). For decades people were just building from source with compilers that had extremely long and undocumented bootstrap chains (they may have documentation for how to bootstrap from a different C or C++ compiler, but there wasn't one that would start from scratch).

I laughed reading the comment above yours. I also laughed reading yours, you are so right on. Next, I am expecting someone telling that there is a javascript on github to automate that build process...

This is not what I was expecting computer science to become, 30 years ago...

Go need a smaller chainloading process from C/C++ too. But the good thing it's there are prebuilt self-contained binary ports from every OS to almost any OS so you can bootstrap it with very little.