On Fri, Apr 24, 2020 at 9:21 PM Miguel Ojeda via SG12 <sg12@lists.isocpp.org> wrote:
On Sat, Apr 25, 2020 at 2:25 AM Richard Smith <richardsmith@googlers.com> wrote:
>
>   There has been no reference implementation of p1315 that has been used in production for any significant amount of time (several years). We do not know that its approach works.

Indeed, there is no reference implementation of exactly P1315, but
there are many implementations out there of the same
idea/function/concept, as referenced by the proposal. They have been
in production use for many years, in systems shipped to billions of
users. The approach definitely works *for what the projects use them*.
Whether that usage is good or not is another question that (see next
point).
I believe Richard is very correct here. P1315 proposes a new mechanism insofar as it suggests that a compiler may (and is encouraged to) avoid involving actual memory for operating on the "secrets" in the first place and thereby gain permission to omit the clearing operation. This suggests a compiler built-in, which is almost the complete opposite of any solutions that depend on the definition of the clearing functions being unknown to the compiler.
 
[ ... ]
Put another way: in the worst case, projects will still use the same,
"wrong" approach. In the best case, they at least avoid bugs related
to their workarounds (trying to achieve the same functionality) and
everyone gets a standard verb to refer to that operation.
In the worst case, the standardized functionality is implemented in a compliant manner that offers less security than the "workarounds" used by the projects. This may be caused by "invention" on the part of the paper or implementers of such in the form of a new compiler built-in.