crossdev arch specific patches

[cinderblock]

Is there a supported way to apply a patch to a specific arch's toolchain?

Let me explain:

I'm working with AVRs and have successfully built a -s4 cross tool chain with crossdev.

The issue is 'avr-size' (from cross-avr/binutils) does not have the 'crossavr-binutils-avr-size.patch' that makes the program output more than what 'size' does.

'avr-size' gives invaluable information about space usage for your specific device.

I looked into editing the ebuild for cross-avr/binutils, but /usr/local/portage/cross-avr/binutils is just a symlink to portage's binutils, which in turn just inherits 'toolchain-binutils'.

I can't edit the local binutils-2.19.1-r1.ebuild to add the patch since it's actually the one from the main portage tree. And even if I could, where would I start since there are no local functions where I would normally put my epatch line?