smtbmc error test case 1

vai_reg/symbiyosys.sby

@@ -3,6 +3,7 @@ depth 30
 wait on
 mode prove
 #mode bmc
+#mode cover
 
 [engines]
 smtbmc

vai_reg/vai_reg.vhd

@@ -111,7 +111,7 @@ begin
             if (DinStop_i = '1') then
               if (unsigned(a_addr) <= 7) then
                 -- Following line results in a Segmentation Fault
-                s_register(to_integer(unsigned(a_addr))) <= Din_i;
+                --s_register(to_integer(unsigned(a_addr))) <= Din_i;
                 -- Following line results in following error:
                 -- ERROR: Unsupported cell type $dlatchsr for cell $verific$wide_dlatchrs_8.$verific$i1$172.
                 s_register(0) <= Din_i;