• via Digitalmars-d-bugs (25/25) Jul 19 2017 https://issues.dlang.org/show_bug.cgi?id=17664

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=17664

          Issue ID: 17664
           Summary: Deprecate implicit casting between shared and unshared
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: spec
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: dfj1esp02 sneakemail.com

---
struct A { int handle; }
shared A b;
void f(A a){ b=a; }
---
This shouldn't compile. Value types include resource identifiers, which may
have threading requirements, e.g. GUI widget handles and OpenGL handles,
assuming they are thread-safe and making them implicitly shared is incorrect.

union A { int handle; int* dummy; }
This can't work as a workaround because it has different size than the handle.

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