add defer: snapshot.dispose()

nimbus/p2p/executor.nim

@@ -12,6 +12,12 @@ proc processTransaction*(tx: Transaction, sender: EthAddress, vmState: BaseVMSta
   trace "Sender", sender
   trace "txHash", rlpHash = tx.rlpHash
 
+  # TODO: we have identical `fork` code in setupComputation.
+  # at later stage, we need to get rid of it
+  # and apply changes in eth_*, debug_* RPC,
+  # macro assembler and premix tool set.
+  # at every place where setupComputation and
+  # processTransaction are used.
   let fork =
     if forkOverride.isSome:
       forkOverride.get
@@ -28,6 +34,8 @@ proc processTransaction*(tx: Transaction, sender: EthAddress, vmState: BaseVMSta
     db.subBalance(sender, upfrontGasCost)
 
   var snapshot = vmState.snapshot()
+  defer: snapshot.dispose()
+
   var computation = setupComputation(vmState, tx, sender, forkOverride)
   var contractOK = true
   result = tx.gasLimit