blockchain_db: store key images for tx without outputs too

src/blockchain_db/blockchain_db.cpp

@@ -60,19 +60,16 @@ void BlockchainDB::add_transaction(const crypto::hash& blk_hash, const transacti
 
   // iterate tx.vout using indices instead of C++11 foreach syntax because
   // we need the index
-  if (tx.vout.size() != 0)  // it may be technically possible for a tx to have no outputs
+  for (uint64_t i = 0; i < tx.vout.size(); ++i)
   {
-    for (uint64_t i = 0; i < tx.vout.size(); ++i)
-    {
-      add_output(tx_hash, tx.vout[i], i, tx.unlock_time);
-    }
+    add_output(tx_hash, tx.vout[i], i, tx.unlock_time);
+  }
 
-    for (const txin_v& tx_input : tx.vin)
+  for (const txin_v& tx_input : tx.vin)
+  {
+    if (tx_input.type() == typeid(txin_to_key))
     {
-      if (tx_input.type() == typeid(txin_to_key))
-      {
-        add_spent_key(boost::get<txin_to_key>(tx_input).k_image);
-      }
+      add_spent_key(boost::get<txin_to_key>(tx_input).k_image);
     }
   }
 }