cpplib: Default language handling, part 1

[Neil Booth]

Joseph S. Myers wrote:-

> > +    case CLK_GNUC89:
> > +      CPP_OPTION (pfile, trigraphs) = 0;
> > +      CPP_OPTION (pfile, dollars_in_ident) = 1;
> > +      CPP_OPTION (pfile, cplusplus_comments) = 1;
> > +      CPP_OPTION (pfile, digraphs) = 0;
> 
> I thought that digraphs were part of GNU89?

Well, if they were, it's only been for 6 months <g>.  I'll change this
item.

Neil.