On Fri, Feb 9, 2018 at 6:34 PM, Tony V E <tvaneerd_at_[hidden]> wrote:

>
>
> On Fri, Feb 9, 2018 at 5:50 PM, David Vandevoorde <daveed_at_[hidden]> wrote:
>
>>
>>
>> On Feb 9, 2018, at 5:46 PM, Richard Smith <richardsmith_at_[hidden]>
>> wrote:
>>
>> On Fri, 9 Feb 2018 at 14:25, David Vandevoorde <daveed_at_[hidden]> wrote:
>>
>>> On Feb 9, 2018, at 4:57 PM, Richard Smith <richardsmith_at_[hidden]>
>>> wrote:
>>>
>>> On Fri, 9 Feb 2018 at 13:08, Myria <myriachan_at_[hidden]> wrote:
>>>
>>>> Is it worth mentioning that an implementation may have other
>>>> mechanisms that create storage in the manner of malloc? For example,
>>>> it'd make sense for VirtualAlloc or mmap to create implicit objects
>>>> just like the standard malloc functions.
>>>>
>>>
>>> Sounds like a good change to me.
>>>
>>>
>>>
>>> It would be nice if we could indicate that in a portable way. The
>>> default is wrong for attributes, unfortunately, but otherwise something
>>> like:
>>>
>>> [[blessed_storage]] void* my_memory_map(…);
>>>
>>> would have been useful.
>>>
>>
>> Yes, it's annoying that attributes don't work out here. I think we won't
>> need any annotations at all in the actual source code for most such
>> functions in practice, because these functions result in syscalls that are
>> opaque to the optimizer anyway (for all it knows, the kernel might have
>> created objects in the storage...). But there are likely exceptions that
>> have a C++ implementation that might get combined with the program source
>> code via link-time optimization, and we do need to avoid bad things
>> happening in that case.
>>
>>
>> Although in those cases the C++ implementation can have a barrier “bless”
>> call on the inside, right?
>>
>>
>>
>>
>>> Incidentally, I’m not too fond of the name “bless”. Maybe
>>> “implicit_lifetime”?
>>>
>>
>> Maybe I should just call it `bikeshed` until this gets to LEWG :)
>>
>>
>> Hopefully nobody will bless bikeshed :-P
>>
>
>
> Didn't LEWG already call it byte_cast? I mean bit_cast?
> How is this different?
>


Sorry, just realized - bit_cast returns the value, not the pointer.



> Or does bit_cast need to call bless/bikeshed?
>
>
>> Daveed
>>
>>
>>
>>
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>>
>>
>
>
> --
> Be seeing you,
> Tony
>

-- 
Be seeing you,
Tony