a design flaw in DIP1035, its remedy, and the implication for @system variables

[Nick Treleaven]

On Wednesday, 13 April 2022 at 12:14:53 UTC, Zach Tollen wrote:
> ```d
> extern int* x;
> @system int y;
>
> void fn() @safe {
>     x = new int; // error: unsafely initialized variable `x` 
> cannot be accessed
>                  //   in @safe code - try marking its 
> declaration @trusted?

That would encourage people to use trusted even when it is 
actually an unsafe value.

...
> They should have forced the user then and there to say whether 
> it was `@trusted` or `@system`.

That would break existing code. @system is a good default for 
extern (C) unsafe globals and functions, even if we make D @safe 
by default.