whats the diff b\w various arm-xx-gcc versions? (newbie)

From: Mayank Kaushik (prehistorictoad2k_at_yahoo.com)
Date: 01/29/05 

Date: 29 Jan 2005 09:49:12 -0800

Hi,

Ive been using ADS till now, but since 45 day trial is gonna end in a
few days, i have decided to switch to the GNU toolchain..and im
painfully new to it.

While searching for the particular toolchain to download, i came
accross many versions..on gnuarm.com i found arm-elf-gcc etc, on
codesourcery.com i found arm-none-eabi-gcc etc, and on the AT91-CDROM i
found arm-linux-gcc etc. Exactly what is the difference between all
these versions of gcc?? how do i decide which one to use?? (i am using
a custom board based on the ARM920t (AT91rm9200), i also have to port a
simple OS like uC/OS to the board.).

Also, will i be able to use code made on one of the above toolchains
with the other? Like, for example, i downloaded the u-boot sourcecode.
The makefile had arm-linux-gcc as the cross-compiler. I tried using
arm-elf-gcc from gnuarm.com, i changed the appropriate variable in the
makefile, but the compiler complained that a particular option in the
makefile "-mshort-load-bytes" was invalid. I removed this option, but
then the linker complained "no space to store headers, use -N" which i
did, and the binary was created. Thats all nice and dandy, but whats
going on???

Thanx in anticipation
Mayank