Re: [v3] install backwards headers in prefix

[Nathan Myers <ncm at nospam dot cantrip dot org>]

On Thu, Dec 14, 2000 at 07:17:59PM -0800, Benjamin Kosnik wrote:
> > > If there are no major objections, I'd like to check this in today.
> > 
> > Yes, I object.  If you want to make it easier to use broken and 
> > obsolete headers, add an option "-iobsolete" or something.  If 
> > iostream.h is in the default directory, we will forever after get 
> > questions about incompatibilities with standard features.  We need 
> > a way to let those headers die peacefully.
> 
> You and I both.
> 
> The only other way around this, that I see, is to add /backward to the 
> directories searched by g++. (Your -iobsolete idea is a bit vague.)

The "-iobsolete" flag would add $(prefix)/backward to the set of
directories searched by g++, as you say.  I just don't want that to 
happen by default.  (It might be "-ibackward", instead, for consistency, 
or $(prefix)/backward might be changed to $(prefix)/obsolete.)
 
> > You might also install an iostream.h in the regular directory
> > containing only the line
> > 
> >   #error <iostream.h> is obsolete; try compiling with ``-iobsolete''.
> 
> In anycase, Alexandre mentioned the thought of adding 
> 
>   #warning this header is deprecated, use <foo> instead of <foo.h>
> 
> to the top of the backwards foo.h headers.
> I think this is a good idea.

I agree the #warning in the backwards/iostream.h (and other .h files,
such as vector.h!) would also be good, in addition to the #error.  The 
more noise we can produce when obsolete, unspecified features are used, 
the better.

Nathan Myers
ncm at cantrip dot org