Add failing test

changing the component size is still unsupported.

Author: petr-bauch

testsuite/gnat2goto/tests/representation_clause_component_size_change/test.adb

@@ -0,0 +1,18 @@
+procedure Test is
+   Storage_Unit : constant := 8;
+   Storage_Unit_Size : constant := 16;
+
+   type Storage_Offset is range
+     -(2 ** (Integer'(Standard'Address_Size) - 1)) ..
+     +(2 ** (Integer'(Standard'Address_Size) - 1)) - Long_Long_Integer'(1);
+
+   type Storage_Element is mod 2 ** Storage_Unit;
+
+   type Storage_Array is
+     array (Storage_Offset range <>) of aliased Storage_Element;
+   for Storage_Array'Component_Size use Storage_Unit_Size;
+
+   My_Storage_Array : constant Storage_Array (1..5) := (1,2,3,4,5);
+begin
+   pragma Assert (My_Storage_Array(2)=2);
+end Test;

testsuite/gnat2goto/tests/representation_clause_component_size_change/test.opt

@@ -0,0 +1 @@
+ALL XFAIL gnat2goto fails with changing component size unsupported

testsuite/gnat2goto/tests/representation_clause_component_size_change/test.py

@@ -0,0 +1,3 @@
+from test_support import *
+
+prove()