From fa182a8794cbf9be1aa91d1d75e65bc7800156bc Mon Sep 17 00:00:00 2001
From: MarcoFalke <falke.marco@gmail.com>
Date: Mon, 11 May 2020 09:59:32 -0400
Subject: [PATCH] rpcwallet: Replace boost::optional<T>::emplace with simple
 assignment of T{}

Optional::emplace() was only added in boost 1.56, see
https://github.com/boostorg/optional/commit/2e583aaf30964afd66c1284aa71d0d8b42fa440d

To simply work around https://github.com/bitcoin/bitcoin/issues/18943,
replace it with assignment of T{}
---
 src/wallet/rpcwallet.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index dda00f1fe..fcf78bd4b 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -1557,8 +1557,8 @@ static UniValue listsinceblock(const JSONRPCRequest& request)
     uint256 blockId;
     if (!request.params[0].isNull() && !request.params[0].get_str().empty()) {
         blockId = ParseHashV(request.params[0], "blockhash");
-        height.emplace();
-        altheight.emplace();
+        height = int{};
+        altheight = int{};
         if (!pwallet->chain().findCommonAncestor(blockId, pwallet->GetLastBlockHash(), /* ancestor out */ FoundBlock().height(*height), /* blockId out */ FoundBlock().height(*altheight))) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }