all OS functions should be "nothrow @trusted @nogc"

[Timon Gehr via Digitalmars-d]

On 27.07.2017 01:56, Andrei Alexandrescu wrote:
> On 07/26/2017 06:16 PM, Steven Schveighoffer wrote:
>> So I guess I should restate that we can assume no implementations 
>> exist that intentionally cause UB when stream is NULL (as in Timon's 
>> example).

My argument was not that we need to fear implementations that take 
explicit measures to screw you, but UB is UB. Compilers can in principle 
turn segfaults into any other behaviour they want, and this behaviour 
can change between releases. I'd just rather not codify guarantees that 
do not exist into the type system, as it is not really feasible to check 
them, even if in practice you will in the overwhelming majority get the 
expected behaviour.

> Either they check for null, and handle gracefully, or don't 
>> check and segfault.
> 
> No need to worry about that at all. If worse comes to worst - i.e. we do 
> port to such an implementation

How do you notice?

> - we can always provide a thin wrapper 
> that checks for NULL then calls the native function. No need to change 
> the signatures. -- Andrei

I don't see how that works, as you'd end up with two different 
implementations of the same C function. (I.e. you get a name clash in 
the object file.)