Check that accessing a struct field that occurs before the start

of the struct (!) works correctly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84853 91177308-0d34-0410-b5e6-96231b3b80d8

test/FrontendAda/negative_field_offset.adb

@@ -5,6 +5,12 @@ procedure Negative_Field_Offset (N : Integer) is
    --  Force use of a thin pointer.
    for String_Pointer'Size use System.Word_Size;
    P : String_Pointer;
+
+   procedure Q (P : String_Pointer) is
+   begin
+      P (1) := 'Z';
+   end;
 begin
    P := new String (1 .. N);
+   Q (P);
 end;