can we un-deprecate .ptr on arrays in @safe code? cf issue 18529

[Steven Schveighoffer]

On 2/27/18 12:32 PM, Atila Neves wrote:

> There's a common case where it's not equivalent - when the pointer is 
> null. Imagine I have a C function I want to call:
> 
> extern(C) void fun(int* things);
> 
> Imagine also that it's ok to call with null. Well, now I can't use a 
> slice to call this and have it be 1) @safe and 2) not throw RangeError. 
> I ran into this the other way.

fun(x.length ? &x[0] : null);

I think even the compiler could elide the bounds check since you already 
did it, but I'm not sure that actually happens.

-Steve