[cfe-dev] Zero'ing Registers on Function Return

[Szabolcs Nagy]

* David Chisnall <David.Chisnall at cl.cam.ac.uk> [2014-09-16 08:53:07 +0100]:
> 
> Now that Colin has blogged about it and there's been a lot of public discussion, it's probably much more difficult to get it published ...
> 

heh i didnt know the idea was supposed to be news, but i think
an implementation would be

the register zeroing came up a lot before, eg. just this year
i could find this one (where alan cox points out the leak in
simd registers):

https://plus.google.com/111049168280159033135/posts/YTDoSRTrktc

the self-test trick i mentioned was invented to address such issues

http://cvsweb.openwall.com/cgi/cvsweb.cgi/Owl/packages/glibc/crypt_blowfish/crypt_blowfish.c.diff?r1=1.22;r2=1.23

and in most related discussions someone goes 'if only the compiler
did this for us..' with various approaches (using a function
attribute is not unheard of)