GCC and system headers

[Laurynas Biveinis]

"Martin v. Loewis" wrote:
> 
> > could somebody explain what are the technical reasons for
> > not allowing ports to choose if they want to use standard
> > headers provided by GCC? Many times I've seen on this
> > mailing list that 'overriding USER_H is a brain-damaged
> > feature' without explanation *how* it is brain-damaged.
> 
> Please elaborate; I'm not aware of any prior discussion of this topic.

See e.g. http://gcc.gnu.org/ml/gcc/1999-09n/msg00827.html and other
messages in this thread.

> What exactly is user.h, and what does it have to do with ports? 

USER_H variable defined in gcc/Makefile. It specifies which GCC
provided headers should be installed on system. Ports could
override it in target makefile fragments.

> And
> who said that they must not choose whether they want to use standard
> headers?

Jeff Law said that many times in the thread mentioned above.

Laurynas Biveinis