Re:Statement Regarding the Zen Programming Language
by mhh__ on Tuesday September 15, 2020 @12:09PM
(#24482927)
The D compiler is now completely open source. It was always source available, but Walter wrote the backend when he was at a different company and he was able to use it but because of copyright it couldn't be open sourced as per se.
Symantec signed off on it a few years ago, it's been Boost licensed ever since.
The only examples that come to mind of a "pure" commercial compiler, not tied to a particular environment or piece of hardware are the Comeau C++ compiler (defunct for well over a decade) and arguably the original D compiler (although I don't know if it qualifies as proprietary, just not open source). Swift as well, although it was open sourced relatively quickly.