chicken-egg problem when building cross toolchain for linux

[Warlich, Christof]

Hi,

as I need to build a couple of cross toolchains for various target architectures (powerpc, mipsel, i686 and arm, all running Linux with glibc), I'd like to generally understand how proceed. Most notably, I'd like to understand the proper sequence to do the job:

1) Configuring, building and installing cross binutils works fine.
2) But when I try to build a bootstrap gcc in the next step, it complains about missing libc header files.
3) Conversely, when I try to install the glibc headers first (make install-headers) , glibc configuration already fails as it does not find the cross compiler:

$ glibc/configure --prefix=3D$PREFIX --host=3D$TARGET --build=3Di686-pc-lin= ux-gnu ...
checking whether gcc -g -O2 -mlong-double-128 uses IBM extended format... n= o checking whether gcc -g -O2 supports -mabi=3Dibmlongdouble... no
configure: error: this configuration requires -mlong-double-128 IBM extende= d format support

Can anyone give me a hint on how to resolve this?

Cheers,

Chris