Two ideas for faster builds

[Yuxuan Shui via Digitalmars-d]

On Thursday, 11 June 2015 at 00:50:01 UTC, Andrei Alexandrescu 
wrote:
> https://issues.dlang.org/show_bug.cgi?id=14679
> https://issues.dlang.org/show_bug.cgi?id=14680
>
> Andrei

As for the .di file, I believe Rust compiler store serialized AST 
in .a and .so. Is it possible that we do the same? And will doing 
that improve build time?