From 37d9e975e9abcac6070e59476fe12e9c92871b09 Mon Sep 17 00:00:00 2001
From: Markus Pilman <markus.pilman@snowflake.com>
Date: Wed, 3 Mar 2021 10:18:03 -0700
Subject: [PATCH] Fix multiple compiler warnings

---
 fdbclient/MultiVersionTransaction.actor.cpp | 2 +-
 fdbclient/MultiVersionTransaction.h         | 1 -
 fdbclient/SystemData.cpp                    | 6 +++---
 fdbserver/BackupProgress.actor.cpp          | 2 +-
 fdbserver/BackupWorker.actor.cpp            | 6 +++---
 fdbserver/MasterProxyServer.actor.cpp       | 2 +-
 6 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/fdbclient/MultiVersionTransaction.actor.cpp b/fdbclient/MultiVersionTransaction.actor.cpp
index 6a931e9cd2..695510fb75 100644
--- a/fdbclient/MultiVersionTransaction.actor.cpp
+++ b/fdbclient/MultiVersionTransaction.actor.cpp
@@ -697,7 +697,7 @@ void MultiVersionTransaction::reset() {
 // MultiVersionDatabase
 MultiVersionDatabase::MultiVersionDatabase(MultiVersionApi* api, int threadIdx, std::string clusterFilePath,
                                            Reference<IDatabase> db, bool openConnectors)
-  : dbState(new DatabaseState()), threadIdx(threadIdx) {
+  : dbState(new DatabaseState()) {
 	dbState->db = db;
 	dbState->dbVar->set(db);
 
diff --git a/fdbclient/MultiVersionTransaction.h b/fdbclient/MultiVersionTransaction.h
index 4a3fb0a9a3..f17925eb73 100644
--- a/fdbclient/MultiVersionTransaction.h
+++ b/fdbclient/MultiVersionTransaction.h
@@ -369,7 +369,6 @@ private:
 	};
 
 	const Reference<DatabaseState> dbState;
-	const int threadIdx;
 	friend class MultiVersionTransaction;
 };
 
diff --git a/fdbclient/SystemData.cpp b/fdbclient/SystemData.cpp
index 3b8845d0aa..f150dc0a78 100644
--- a/fdbclient/SystemData.cpp
+++ b/fdbclient/SystemData.cpp
@@ -55,7 +55,7 @@ const Value keyServersValue( Standalone<RangeResultRef> result, const std::vecto
 	std::vector<Tag> destTag;
 
 	bool foundOldLocality = false;
-	for (const KeyValueRef kv : result) {
+	for (const KeyValueRef& kv : result) {
 		UID uid = decodeServerTagKey(kv.key);
 		if (std::find(src.begin(), src.end(), uid) != src.end()) {
 			srcTag.push_back( decodeServerTagValue(kv.value) );
@@ -107,7 +107,7 @@ void decodeKeyServersValue( Standalone<RangeResultRef> result, const ValueRef& v
 	src.clear();
 	dest.clear();
 
-	for (const KeyValueRef kv : result) {
+	for (const KeyValueRef& kv : result) {
 		Tag tag = decodeServerTagValue(kv.value);
 		if (std::find(srcTag.begin(), srcTag.end(), tag) != srcTag.end()) {
 			src.push_back( decodeServerTagKey(kv.key) );
@@ -120,7 +120,7 @@ void decodeKeyServersValue( Standalone<RangeResultRef> result, const ValueRef& v
 	std::sort(dest.begin(), dest.end());
 	if(missingIsError && (src.size() != srcTag.size() || dest.size() != destTag.size())) {
 		TraceEvent(SevError, "AttemptedToDecodeMissingTag");
-		for (const KeyValueRef kv : result) {
+		for (const KeyValueRef& kv : result) {
 			Tag tag = decodeServerTagValue(kv.value);
 			UID serverID = decodeServerTagKey(kv.key);
 			TraceEvent("TagUIDMap").detail("Tag", tag.toString()).detail("UID", serverID.toString());
diff --git a/fdbserver/BackupProgress.actor.cpp b/fdbserver/BackupProgress.actor.cpp
index 3f1d564c16..f496ec0558 100644
--- a/fdbserver/BackupProgress.actor.cpp
+++ b/fdbserver/BackupProgress.actor.cpp
@@ -121,7 +121,7 @@ std::map<std::tuple<LogEpoch, Version, int>, std::map<Tag, Version>> BackupProgr
 			}
 		}
 
-		for (const Tag tag : tags) { // tags without progress data
+		for (const Tag& tag : tags) { // tags without progress data
 			tagVersions.insert({ tag, adjustedBeginVersion });
 			TraceEvent("BackupVersionRange", dbgid)
 			    .detail("OldEpoch", epoch)
diff --git a/fdbserver/BackupWorker.actor.cpp b/fdbserver/BackupWorker.actor.cpp
index bf71892934..cf18776d48 100644
--- a/fdbserver/BackupWorker.actor.cpp
+++ b/fdbserver/BackupWorker.actor.cpp
@@ -504,7 +504,7 @@ ACTOR Future<Void> setBackupKeys(BackupData* self, std::map<UID, Version> savedL
 			state std::vector<Future<Optional<Version>>> prevVersions;
 			state std::vector<BackupConfig> versionConfigs;
 			state std::vector<Future<Optional<bool>>> allWorkersReady;
-			for (const auto [uid, version] : savedLogVersions) {
+			for (const auto& [uid, version] : savedLogVersions) {
 				versionConfigs.emplace_back(uid);
 				prevVersions.push_back(versionConfigs.back().latestBackupWorkerSavedVersion().get(tr));
 				allWorkersReady.push_back(versionConfigs.back().allWorkerStarted().get(tr));
@@ -569,7 +569,7 @@ ACTOR Future<Void> monitorBackupProgress(BackupData* self) {
 			if (self->recruitedEpoch == self->oldestBackupEpoch) {
 				// update update progress so far if previous epochs are done
 				Version v = std::numeric_limits<Version>::max();
-				for (const auto [tag, version] : tagVersions) {
+				for (const auto& [tag, version] : tagVersions) {
 					v = std::min(v, version);
 				}
 				savedLogVersions.emplace(uid, v);
@@ -781,7 +781,7 @@ ACTOR Future<Void> saveMutationsToFile(BackupData* self, Version popVersion, int
 		    .detail("TagId", self->tag.id)
 		    .detail("File", file->getFileName());
 	}
-	for (const UID uid : activeUids) {
+	for (const UID& uid : activeUids) {
 		self->backups[uid].lastSavedVersion = popVersion + 1;
 	}
 
diff --git a/fdbserver/MasterProxyServer.actor.cpp b/fdbserver/MasterProxyServer.actor.cpp
index d3c69651df..2c42eb1283 100644
--- a/fdbserver/MasterProxyServer.actor.cpp
+++ b/fdbserver/MasterProxyServer.actor.cpp
@@ -2294,7 +2294,7 @@ ACTOR Future<Void> masterProxyServerCore(
 					state KeyRange txnKeys = allKeys;
 					Standalone<RangeResultRef> UIDtoTagMap = commitData.txnStateStore->readRange( serverTagKeys ).get();
 					state std::map<Tag, UID> tag_uid;
-					for (const KeyValueRef kv : UIDtoTagMap) {
+					for (const KeyValueRef& kv : UIDtoTagMap) {
 						tag_uid[decodeServerTagValue(kv.value)] = decodeServerTagKey(kv.key);
 					}
 					loop {