dmd -c behaviour doesn't take account of packages.

[Bernard Helyer]

A discussion on the Mono-D IRC channel just made me realise 
something.

     dmd -c foo/a.d  bar/a.d

The second module overwrites the first. This makes using 'pass 
everything at once' with Mono-D (IDE plugin) 
difficult/impossible. As far as I'm concerned, it's just a bug 
that's never come up. The solution is trivial, of course. Prepend 
package names so you get foo_a.o and bar_a.o. Either that or 
allow specific output paths to be specified per-object. Or just 
produce one object file. Anything _but_ the current behaviour, in 
fact.