dip1000 and preview in combine to cause extra safety errors

[Walter Bright]

On 6/8/2022 5:38 PM, Timon Gehr wrote:
> This does not have anything to do with `@safe` by default, it's just an 
> inconsistency in the compiler implementation.

I could make a case for every one of the safety checks being checked in @system 
code, too.

The existing checks you note were there long before @safe/@trusted/@system was 
added. Them remaining is an artifact of evolution and a wish to support legacy 
behavior.