[PATCH] add __amd64__ predefined symbols

[Zack Weinberg]

Jan Hubicka <jh@suse.cz> writes:

> The naming change is bit problematic.  We still have only one choice to
> define for "machine" and I don't think we can change it from "x86_64"
> settings at this stage.  Still I guess it is least confusing to the user
> if both of the macors were defined.

Assertions are deprecated; for a new target like this, you shouldn't
use builtin_assert at all.

zw