https://issues.dlang.org/show_bug.cgi?id=24783

          Issue ID: 24783
           Summary: ref and out declarations can be initialized with null
                    references
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

@safe:

  void test(ref int r, out int o);

  void foo() {
    int* p;
    test(*p, *p);
  }

compiles without complaint. They should get a null check.

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