[PATCH 2/4] New string function explicit_bzero (from OpenBSD).

[Florian Weimer]

On 08/18/2016 10:53 PM, Torvald Riegel wrote:
> On Thu, 2016-08-18 at 20:31 +0200, Florian Weimer wrote:
>> I don't think we want explicit_bzero to be inlined, it's useful to have
>> this name in the executable.  Furthermore, we might want to add
>> additional state clearing later, so an implementation in libc.so.6 seems
>> desirable anyway.
>>
>> For an implementation in libc, there is currently no different between
>> the __glibc_read_memory kludge and a full memory barrier, so I suggest
>> to go with the latter.  (The explicit_bzero call will serve as a rather
>> broad barrier anyway, but we can annotate it with __THROW.)
>
> I suppose we just want a compiler barrier here though, and don't need a
> memory barrier in the sense of something that constrains HW reordering.

Yes, I meant an asm statement with a "memory" clobber.

Thanks,
Florian