Creating U-Boot.bin

Hi all,
I follow this to make Boot.bin :
http://elinux.org/BeagleBoard_Ubuntu_%26_DSP_From_Sources#U-Boot

I do this

/*
git clone git://www.sakoman.com/git/u-boot.git
cd u-boot
git checkout omap4-exp
make CROSS_COMPILE=arm-none-eabi- distclean
make CROSS_COMPILE=arm-none-eabi- omap3_beagle_config
make CROSS_COMPILE=arm-none-eabi-
*/

and first every thing looks OK (starts to build) but after 30-40sek .
I receive:

(other messages)******************** /home/tisho/BB_Tests/u-boot/arch/
arm/lib/eabi_compat.o -L /usr/lib/gcc/arm-linux-gnueabi/4.6.1 -lgcc -
Map u-boot.map -o u-boot
make: *** [u-boot] Error 139

I am new and I don't know what means this error. And what to do.

Thank you guys :))

If your going to build your own u-boot.bin, why not use one of the
mainline u-boot official release tag's? (unless your building for an
xM C, then use Angstrom's..)

Regards,

Board is XM rev.B.
My initial idea is to turn on the SPI of the board. I wont to use
Ubintu and I start to read.
I understad that I should to modify the u-boot.bin and the kernel, but
first decide to make working Ubuntu and then modify it :))
What you advise me.

Regards,