https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110816
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
Last reconfirmed| |2023-07-26
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> The only way to access that byte is to use memcpy or via char.
> -ftrivial-auto-var-init is not designed for security this way but rather for
> normal code ...
That's not what the manual says (emphasis mine):
"Initialize automatic variables with either a pattern or with zeroes to
increase the security and predictability of a program by preventing
**uninitialized memory disclosure** and use."
> IIRC atomic compare and swap will zero it out too ...
The std::atomic and std::atomic_ref compare_exchange members will zero it, but
the compiler built-in won't.
