Hi Pedro,

Our Windows machine was so slow building GDB today that it gave me
extra time to work on this (between various build failures :-().
So here's a patch.

Do you think that the implementation for "target_kill" is good?
That was my first implementation until I realized that the to_kill
field is inherited. So perhaps I can simplify the implementation by
calling the to_kill field from the target layer that's at the top
of the current target stack?

Other than that, I think I got all implementations, and I recompiled
all the files that I could recompile on my x86_64-linux machine.
I also built GDB with --enable-targets=all, even if I don't think
it help test that much more since most impacted files are "native"
units.

-- 
Joel