What happened to phobos compile time?

[RazvanN]

Hello everyone!

I just tried compiling phobos on machine to get updated with the 
latest changes and I noticed an explosion in compile time. On my 
machine it takes roughly 5 minutes (!!!) to compile it while last 
year it took somewhere around 15-30 seconds. Does anyone know 
what has caused this serious performance regression?

Thanks for answers,
RazvanN