[Issue 17449] [DIP1000] crash due to covariant conversion of scope delegate to delegate

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=17449

Walter Bright <bugzilla at digitalmars.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |INVALID

--- Comment #2 from Walter Bright <bugzilla at digitalmars.com> ---
Adding `@safe` to main() causes the compiler error message:

test.d(8): Error: `@safe` function `D main` cannot call `@system` delegate `dg`

which looks appropriate. Adding more @safe:


  @safe void main() {
    void delegate() @safe dg;
    void savedg(void delegate() @safe h) { dg = h; }
    void foo(int x) { savedg({ assert(x == 42); }); }
    foo(42);
    dg();
  }

Makes it compile and run successfully. Checking the generated code, it is
generating a closure.

So it looks correct. -dip1000 isn't enough, using @safe is also necessary.

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