Kerenel Compiled with x86_64 gcc vs. i686 gcc

Hello,

I want to launch 2.6.29 on a dual core PC104.
I used an i686-unknown-linux-gnu with ARCH=x86 and created a bzImage that works fine.
Then I used an x86_64-unknown-linux-gnu with ARCH=x86_64.

The file system I used (busybox) was compiled with the same compiler as the kernel.

What is the added value (if any) of the last one ?

Thanks.

Is the processor on the board 64 bit? If so then you should optimize for it, though I can't really think of many situations that 64 bit support would be terribly helpful in an embedded platform like PC104.

64 bit support is better for large and complex programs consuming massive amounts of resources, which sounds like exactly the sort of thing you don't run on a PC104.