use invariant

Author: Daniel Kroening

src/goto-programs/link_goto_model.cpp

@@ -104,7 +104,8 @@ static bool link_functions(
       {
         // the linking code will have ensured that types match
         rename_symbol(src_func.type);
-        assert(base_type_eq(in_dest_symbol_table.type, src_func.type, ns));
+        INVARIANT(base_type_eq(in_dest_symbol_table.type, src_func.type, ns),
+                  "linking ensures that types match");
       }
     }
   }
@@ -117,7 +118,7 @@ static bool link_functions(
     {
       const symbolt &symbol=it->second;
 
-      assert(symbol.value.id()==ID_symbol);
+      INVARIANT(symbol.value.id()==ID_symbol, "must have symbol");
       const irep_idt &id=to_symbol_expr(symbol.value).get_identifier();
 
       #if 0
@@ -126,7 +127,8 @@ static bool link_functions(
         std::cerr << symbol << '\n';
         std::cerr << ns.lookup(id) << '\n';
       }
-      assert(base_type_eq(symbol.type, ns.lookup(id).type, ns));
+      INVARIANT(base_type_eq(symbol.type, ns.lookup(id).type, ns),
+                "type matches");
       #endif
 
       macro_application.insert_expr(symbol.name, id);