Re: Slight improvement to common.make

[Nicola Pero]

> > I've made the patch OS X specific, then committed to CVS.
> 
> Text output while compiling is significantly reduced; obsolete 
> info is removed. Others might benefit as well?

You can turn on removal of empty dirs from the flags on any platform, by
setting REMOVE_EMPTY_DIRS=yes (in the makefile or in the shell
environment).

I like the simpler compiler commad line ... I didn't make it default on
all platforms simply because it is slightly slower.  My compilation test
would take 11 seconds (approx) instead of 10 seconds (approx) on my
machine <I don't think I can remove this delay, which is due to scanning
the dirs - also note that my dirs are pretty empty ... if you install a
lot of libs and headers it takes more time>.  I am under the assumption
that most people don't really care about the compiler command line (we
might likely add an option to hide completely the compiler commands in the
future), and prefer compilation to be faster.

Anyway yes - anyone wanting empty system/local/network/user dirs
automatically removed from their -I and -L flags can set REMOVE_EMPTY_DIRS
in the makefiles or in the environment ... the command line is quite
prettier then.