Better error message when too many dynamic objects

regression/cbmc/address_space_size_limit1/test.desc

@@ -1,5 +1,5 @@
 CORE
 test.c
 --no-simplify --unwind 300
-too many variables
+too many addressed objects
 --

src/solvers/flattening/bv_pointers.cpp

@@ -683,7 +683,7 @@ void bv_pointerst::add_addr(const exprt &expr, bvt &bv)
   std::size_t a=pointer_logic.add_object(expr);
 
   if(a==(std::size_t(1)<<object_bits))
-    throw "too many variables";
+    throw "too many addressed objects";
 
   encode(a, bv);
 }