struct conversion supports complex shadowing

test/basic/struct_shadow.v

@@ -0,0 +1,48 @@
+// While this might look silly, you'll notice that the sections are actually
+// different. We are ensuring that the correct struct definitions are being used
+// in each scope.
+module top;
+    reg [2:0] a = 3'b111;
+    reg [2:0] b = 3'b111;
+    reg [2:0] c = 3'b111;
+    reg [2:0] d = 3'b111;
+    reg [2:0] e = 3'b111;
+    reg [2:0] f = 3'b111;
+    integer i = 2;
+    integer j = 2;
+    integer k = 2;
+    initial begin
+        $display("A: 000 -> 000000");
+        $display("A: 001 -> 121424");
+        $display("A: 010 -> 214142");
+        $display("A: 011 -> 335566");
+        $display("A: 100 -> 442211");
+        $display("A: 101 -> 563635");
+        $display("A: 110 -> 656353");
+        $display("A: 111 -> 777777");
+        $display("B: 000 -> 000000");
+        $display("B: 001 -> 214241");
+        $display("B: 010 -> 141422");
+        $display("B: 011 -> 355663");
+        $display("B: 100 -> 422114");
+        $display("B: 101 -> 636355");
+        $display("B: 110 -> 563536");
+        $display("B: 111 -> 777777");
+        $display("C: 000 -> 000000");
+        $display("C: 001 -> 142412");
+        $display("C: 010 -> 414221");
+        $display("C: 011 -> 556633");
+        $display("C: 100 -> 221144");
+        $display("C: 101 -> 363556");
+        $display("C: 110 -> 635365");
+        $display("C: 111 -> 777777");
+        $display("D: 000 -> 000000");
+        $display("D: 001 -> 424121");
+        $display("D: 010 -> 142214");
+        $display("D: 011 -> 566335");
+        $display("D: 100 -> 211442");
+        $display("D: 101 -> 635563");
+        $display("D: 110 -> 353656");
+        $display("D: 111 -> 777777");
+    end
+endmodule