[Bug rtl-optimization/69482] Writing through pointers to volatile not always preserved

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69482

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2016-01-26
                 CC|                            |rguenth at gcc dot gnu.org
            Version|unknown                     |5.3.0
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  It might be a non-issue as RTL expansion assigns 'x' to a register,
thus we only omit zeroing the respective register.

'x' is assigned a register because 'x' is not volatile qualified and register
sets in RTL are not "volatile".

As said, this is a non-issue for secure memset in practice - secure deletion
has to make sure to clobber all CPU registers as well (as well as possibly
used stack space that registers with sensitive information could have been
spilled to).