[Clfs-support] Questions on building ARM uclibc cross-toolchain.

[dangbinghoo]

Hello kindly man, 
Yestorday I putted a question on about the error while building Embedded
ARM uClibc-0.9.29 toochains,warmhearted Joe Ciccone pointed me to the
trac ticket,the ticket almost solved the problem,this is ok.But there is
a futher problem: I used to build a cross toochain for arm use buildroot
tool,this is the official commendatory utility for generate a
cross-compilation toolchain and root filesystem for specific target
Linux system using the uClibc C library.And the order buildroot take for
building is:
	1.linux kernel-headers
	2.uClibc-headers (build command is like this: 
/usr/bin/make -j1
-C /mnt/develope/buildroot/toolchain_build_arm/uClibc-0.9.29 \
PREFIX=/mnt/develope/buildroot/toolchain_build_arm/uClibc_dev/ \
DEVEL_PREFIX=/usr/ \
RUNTIME_PREFIX=/mnt/develope/buildroot/toolchain_build_arm/uClibc_dev/ \
HOSTCC="/usr/bin/gcc" \
oldconfig),
	actually the build was always failed,and it was just simplely ignored.
	3.gmp
	4.mpfr (both gmp and mpfr built twice,one for host,and one for the
target)
	5.binutils
	6.gcc-pass1
	...

So,my questions are : 
	a. What actually the step 2 do?
	b. In step 2, "RUNTIME_PREFIX" and "HOSTCC" used for what?
	c. What gmp and mpfr used for ? How if I want to add them to the
toolchain?I like the command can build things from scratch.

Anybuddy help me please?

Build a clfs system for embeded target makes me excited. Well,I am
almost expecting the cblfs,to build a blfs based on gnome-mobile.That
wouled be greate!

I'am Chinese,sorry for my poor english, Thanks  a lot!