missing API for locale_t in <locale.h>

[Roland McGrath]

> The only point I'm not sure about is that a few lines below there is some
> code that purports to avoid dragging in all categories at link time when
> linking statically:

It does the opposite of that.  In the NL_CURRENT_INDIRECT case (i.e. static
linking with __thread support), the normal macros avoid bringing in all
categories.  However, any static program that uses nl_langinfo must bring
in all categories since the runtime item argument may refer to any one.
The switch version makes sure there are references to bring all categories in.
There is no issue with the name arrays, they are always maintained the same.