[Bug driver/87769] GCC build from source uses headers and libraries from directories host machine.

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87769

--- Comment #6 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
If you want the modern process for building a cross toolchain for a 
GNU/Linux (or GNU/Hurd) target, look at how glibc's build-many-glibcs.py 
does it.  (This is not saying you need to use build-many-glibcs.py - 
rather, that studying the script will show you the modern process, which 
you can then integrate into your own toolchain build, whereas many scripts 
and instructions out there for building cross toolchains have a lot of 
obsolete code in them handling things that may have been issues ten years 
ago but haven't been needed for a long time now and are not now the 
recommended way to do things.)

As building a cross toolchain is something that involves builds of several 
different components in the right sequence, and each component has its own 
maintainers and documentation concerned specifically with that one 
component, the overall process doesn't fit easily in the documentation for 
any one toolchain component.  The GCC documentation only naturally 
describes how to build GCC, leaving it to the reader to deduce how to 
compose multiple builds of GCC and other components if they wish to build 
a whole toolchain.