add regression test for #120

Author: oli-obk

tests/run-pass/recursive_static.rs

@@ -0,0 +1,11 @@
+#![feature(static_recursion)]
+
+struct S(&'static S);
+static S1: S = S(&S2);
+static S2: S = S(&S1);
+
+fn main() {
+    let p: *const S = S2.0;
+    let q: *const S = &S1;
+    assert_eq!(p, q);
+}