GCC headers and DJGPP port

[Martin v. Loewis]

> For example, the headers installed by GCC use various macros to avoid
> redefinitions and multiple typedefs.  Using these headers means that
> the library developers need to know about all of these special macros,
> lest some change in the library breaks them.  Likewise, the GCC port
> maintainers need to know about all the subtleties of the library
> internals, to prevent changes in GCC headers from breaking the
> library.

There is a technical need that the compiler proper and its header
files agree on certain things, so there will be some overlap. It's not
the overlap that hurts, but the fact that there is disagreement what
each header must provide and what it must not provide. If we can agree
on an interface, danger of breaking things between releases will be
smaller.

Regards,
Martin