From c60491eef175eda6fae749c48066039f75b34999 Mon Sep 17 00:00:00 2001
From: Kittywhiskers Van Gogh <63189531+kittywhiskers@users.noreply.github.com>
Date: Mon, 4 May 2020 10:50:43 +0100
Subject: [PATCH] merge #18863: Make CScriptVisitor stateless

---
 src/script/standard.cpp | 34 ++++++++++++++--------------------
 1 file changed, 14 insertions(+), 20 deletions(-)

diff --git a/src/script/standard.cpp b/src/script/standard.cpp
index 4211385d57..e7a0b2fdff 100644
--- a/src/script/standard.cpp
+++ b/src/script/standard.cpp
@@ -202,38 +202,32 @@ bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::
 
 namespace
 {
-class CScriptVisitor : public boost::static_visitor<bool>
+class CScriptVisitor : public boost::static_visitor<CScript>
 {
-private:
-    CScript *script;
 public:
-    explicit CScriptVisitor(CScript *scriptin) { script = scriptin; }
-
-    bool operator()(const CNoDestination &dest) const {
-        script->clear();
-        return false;
+    CScript operator()(const CNoDestination& dest) const
+    {
+        return CScript();
     }
 
-    bool operator()(const CKeyID &keyID) const {
-        script->clear();
-        *script << OP_DUP << OP_HASH160 << ToByteVector(keyID) << OP_EQUALVERIFY << OP_CHECKSIG;
-        return true;
+    CScript operator()(const CKeyID& keyID) const
+    {
+        return CScript() << OP_DUP << OP_HASH160 << ToByteVector(keyID) << OP_EQUALVERIFY << OP_CHECKSIG;
     }
 
-    bool operator()(const CScriptID &scriptID) const {
-        script->clear();
-        *script << OP_HASH160 << ToByteVector(scriptID) << OP_EQUAL;
-        return true;
+    CScript operator()(const CScriptID& scriptID) const
+    {
+        return CScript() << OP_HASH160 << ToByteVector(scriptID) << OP_EQUAL;
     }
 };
+
+const CScriptVisitor g_script_visitor;
+
 } // namespace
 
 CScript GetScriptForDestination(const CTxDestination& dest)
 {
-    CScript script;
-
-    boost::apply_visitor(CScriptVisitor(&script), dest);
-    return script;
+    return boost::apply_visitor(::g_script_visitor, dest);
 }
 
 CScript GetScriptForRawPubKey(const CPubKey& pubKey)