Deprecate -fno-honor-std?

[Joe Buck]

> 
> > Why do it this way instead of in the compiler?  So that it will be
> > possible to build the old library with the new compiler, to make speed
> > comparisons possible (to find out, say, how much do we lose with the new
> > headers?
> 
> That will not work.  There are lots of other reasons the old library
> won't work with the new compiler, including that the compiler makes
> assumptions about typeinfo, etc., that are incompatible with the old
> library.  They're relatively tightly coupled.  Does that change your
> stance?

Ok, I guess it's not worth bothering with keeping it alive.