Right, I know, but for us x86-64 performance is so far from what we
need that I am working on another patch to gain performance in
a different way in any case. On the other hand without validation
our user experience is dreadful - less than one run in 10 on a
largish application escapes death in access_me. I did try more
selective validation but it didn't work for us.
Forgot to add: Defaulting the compile time option to always validate is fine. Getting rid of the address validation requires complete control of the compile/runtime environment, which is not feasible for many people.
-Arun