cross building binutils?

[Nomen Nescio]

> > Can somebody please point me to the official instructions for cross building
> > binutils? Thank you.
> 
> In this website https://launchpad.net/gcc-arm-embedded, you can find
> how we cross build binutils for arm-none-eabi. You can use it as an
> example. The detailed build scripts are in the source packages.

Thanks I'll have a look.

I understand I have to set the target machine. I haven't seen any
explanation of what I have to available on the host. I saw one unofficial
web page where the guy copied every header file and library from the target
onto his host. Isn't there a list of what's necessary or am I (probably)
missing something?

Also can I cross build for multiple targets on one host or do I have to
build binutils n times for n targets? If I can build one cross binutils for
multiple targets, how do I arrange the header files and libraries?