HOWTO BUILD A CROSS COMPILER WITH EMERGE !

HOWTO BUILD A CROSS COMPILER WITH EMERGE !   ------------------------------------------------------------   Before you read any further, you should try using 'crossdev'  in portage.  You're less likely to screw something up that  way.  Simply do `emerge '>=crossdev-0.9'` and then execute  `crossdev --help`.  The insturctions below are for those who wish to learn  more about the details of how crossdev works wrt portage. You could probably give two shits, so just use crossdev !   ------------------------------------------------------------   ------------- PACKAGE NOTES -------------   - binutils      Only binutils versions that 'inherit toolchain-binutils'      will work.  The host system should also being using one       of these versions or you'll probably break your system.  - linux-headers      Any version that has 'inherit kernel-2' should work.  - gcc      Only gcc versions that 'inherit toolchain' will work.        Supported versions:         3.3.6+         3.4.6+         4.0.3+         4.1.1+      Anything else you're on your own.  - glibc      Supported versions:         2.3.6-r4+         2.4-r3+      Anything else you're on your own.  ------------- GENERAL NOTES -------------   - ARCH / USE      sometimes you may have to pass ARCH / USE to the emerge       process for things to work properly.  For example, glibc       will only apply hppa patches if 'hppa' is in ARCH / USE.        This is a bug and I am working on fixing it :).  - CFLAGS      All packages should be built with your HOST's CFLAGS       except for glibc.  When building glibc, change your CFLAGS       to something for the target host.  ------------- ON TO THE FUN -------------  (1) Pick your target.  Any valid 'CHOST' will do.  I will be  using 'hppa2.0-unknown-linux-gnu'.  (2) Setup 'categories'. $ mkdir -p /etc/portage $ echo cross-hppa2.0-unknown-linux-gnu >> /etc/portage/categories  (3) Setup PORTDIR_OVERLAY. For more info, see make.conf(5) manpage. My overlay is /usr/local/portage.  $ mkdir -p /usr/local/portage/cross-hppa2.0-unknown-linux-gnu $ cd /usr/local/portage/cross-hppa2.0-unknown-linux-gnu $ ln -s /usr/portage/sys-devel/binutils binutils $ ln -s /usr/portage/sys-devel/gcc gcc $ ln -s /usr/portage/sys-kernel/linux-headers linux-headers $ ln -s /usr/portage/sys-libs/glibc glibc  (4) Emerge binutils. $ emerge cross-hppa2.0-unknown-linux-gnu/binutils  (5) Emerge gcc [C compiler only]. $ USE=nocxx emerge cross-hppa2.0-unknown-linux-gnu/gcc < run gcc-config for the new compiler >  (6) Emerge linux headers. $ emerge cross-hppa2.0-unknown-linux-gnu/linux-headers  (7) Emerge glibc. $ USE=hppa emerge cross-hppa2.0-unknown-linux-gnu/glibc  (8) Emerge gcc [C and C++ compiler]. $ emerge cross-hppa2.0-unknown-linux-gnu/gcc  (9) Build stuff ! When you go to emerge packages, you should just need to do:  ROOT=/blah/ CHOST=hppa2.0-unknown-linux-gnu emerge cpio  - you should also set CBUILD to your building machine for     completeness sake ... most of the time you won't need it,     but sometimes you will :)  - CTARGET is no longer needed so don't set it !  If you want to cross compile a kernel, do this:  make ARCH=hppa CROSS_COMPILE=hppa2.0-unknown-linux-gnu-