From b7e58f9c1d9969a26f002613fe6e6fbf9c1def3d Mon Sep 17 00:00:00 2001
From: Andrew Chow <achow101-github@achow101.com>
Date: Tue, 11 Sep 2018 00:11:00 -0400
Subject: [PATCH] Convert non-witness UTXOs to witness if witness sig created

If a witness signature was created when a non-witness UTXO is used,
convert the non-witness UTXO to a witness one.
---
 src/wallet/rpcwallet.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index cbbac4dca..e313a7743 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -3988,6 +3988,13 @@ UniValue sethdseed(const JSONRPCRequest& request)
     return NullUniValue;
 }
 
+        if (sigdata.witness) {
+            // Convert the non-witness utxo to witness
+            if (input.witness_utxo.IsNull() && input.non_witness_utxo) {
+                input.witness_utxo = input.non_witness_utxo->vout[txin.prevout.n];
+            }
+        }
+
 UniValue walletprocesspsbt(const JSONRPCRequest& request)
 {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);