Proposed improvements to the separate compilation model

[so]

On Sun, 24 Jul 2011 01:47:32 +0300, Andrei Alexandrescu  
<SeeWebsiteForEmail at erdani.org> wrote:

> and then either remove the .tmp if identical or rename it forcefully to  
> filename.di if different. That's a classic in code generation tools.

Not sure i got it right but how renaming it forcefully would solve this?
This must be two separate process for the compiler, issuing an error and  
if it was intended then the .di file must be generated.