Plan to Make stub.c Compile with Cosmocc for Long-Term Adaptability

[shinokaro]

We are planning to make stub.c compilable with Cosmocc. This is a low-priority goal and part of a long-term plan. Most Ruby developers are not familiar with the Windows API, and it may be more beneficial to modify the source code to assume a POSIX environment.

https://github.com/jart/cosmopolitan