memcpy() comparison: C, Rust, and D

[John Colvin via Digitalmars-d]

On Tuesday, 31 January 2017 at 10:17:09 UTC, Olivier FAURE wrote:
> On Tuesday, 31 January 2017 at 01:30:48 UTC, Walter Bright 
> wrote:
>> 3. Nothing s2 transitively points to is altered via s2.
>
> Wait, really? Does that mean that this code is implicitly 
> illegal?
>
> import core.stdc.string;
>
>     void main()
>     {
>         int*[10] data1;
>         int*[10] data2;
>
>         memcpy(data1.ptr, data2.ptr, 10);
>     }
>
> Since memcpy is @system, I have no way to know for sure (the 
> compiler obviously won't warn me since I can't mark main as 
> @safe), so I'd argue the prototype doesn't carry that 
> information.

Point 3 is about `const`, which as far as I know is unaffected by 
application of @safe. Did you mean to quote a different point?