Besides the legal side of things, the code might be being built with an company internal tool-chain, and comercial compilers, so it would be a bunch of work to even get it ready for a public release. All of this reinventing of the wheel probably limits nice fixes for common bugs over the years.
Compiler issues shouldn't hold you back. Release it anyway. If someone is interested enough, they will more than likely be willing to work with what they can get. Let the burden of correcting the code fall on them.
While that sounds good in theory, when customers are involved, you want to make sure that you have your best foot forward. So filling up forums with complaints is never a good thing.
