_GLIBCPP_USE_WCHAR_T undefined in FreeBSD's c++config.h?

[Benjamin Kosnik]

>Once configure detects that FreeBSD supports all the required wchar
>features, then I will get serious about it.  I will also double-check
>the configure process itself from time to time.  Sorry, but you can't
>squeeze grape juice from a turnip (unless you have a Midas-like touch).

Seems sane. 

I was just heartened to know that it was possible at all: the
patches/hacks seem pretty minor at this point, compared to where we were
a year ago.

-benjamin