https://issues.dlang.org/show_bug.cgi?id=24631

          Issue ID: 24631
           Summary: Pointer cast allows changing @system field in @safe
                    code
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: nick@geany.org

struct S
{
    @system int i;
}

void main() @safe
{
    S s;
    auto p = cast(int*) &s;
    *p = 8;

    int i = 8;
    auto ps = cast(S*) &i;
}

PR incoming.

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