https://issues.dlang.org/show_bug.cgi?id=15292

          Issue ID: 15292
           Summary: [REG2.068.0] Segmentation fault with self-referencing
                    struct
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ice
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: thecybershadow@gmail.com

>From http://stackoverflow.com/q/33553013/21501:

///////////// test.d ////////////
import std.typecons;

struct Node {
    int value;
    NullableRef!Node left, right;
}

void main() {
    Node n;
}
/////////////////////////////////

Introduced in https://github.com/D-Programming-Language/dmd/pull/4820

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