Core/Misc: Fixed clang 13 warnings, gcc 11 build errors and nopch build

src/server/game/AI/SmartScripts/SmartScriptMgr.cpp

@@ -1287,7 +1287,7 @@ bool SmartAIMgr::IsEventValid(SmartScriptHolder& e)
                 TC_LOG_ERROR("sql.sql", "SmartAIMgr: Entry " SI64FMTD " SourceType %u Event %u Action %u has invoker cast action, but event does not provide any invoker!", e.entryOrGuid, e.GetScriptType(), e.GetEventType(), e.GetActionType());
                 return false;
             }
-            // no break
+            /* fallthrough */
         case SMART_ACTION_SELF_CAST:
         case SMART_ACTION_ADD_AURA:
             if (!IsSpellValid(e, e.action.cast.spell))

src/server/game/BattlePets/BattlePetMgr.h

@@ -128,7 +128,7 @@ public:
         void CalculateStats();
 
         WorldPackets::BattlePet::BattlePet PacketInfo;
-        std::unique_ptr<DeclinedName> DeclinedName;
+        std::unique_ptr<::DeclinedName> DeclinedName;
         BattlePetSaveInfo SaveInfo = BATTLE_PET_UNCHANGED;
     };
 

src/server/game/Entities/Object/Object.cpp

@@ -142,7 +142,6 @@ void Object::BuildCreateUpdateBlockForPlayer(UpdateData* data, Player* target) c
 
     uint8 updateType = UPDATETYPE_CREATE_OBJECT;
     uint8 objectType = m_objectTypeId;
-    uint16 objectTypeMask = m_objectType;
     CreateObjectBits flags = m_updateFlag;
 
     if (target == this)                                      // building packet for yourself
@@ -150,7 +149,6 @@ void Object::BuildCreateUpdateBlockForPlayer(UpdateData* data, Player* target) c
         flags.ThisIsYou = true;
         flags.ActivePlayer = true;
         objectType = TYPEID_ACTIVE_PLAYER;
-        objectTypeMask |= TYPEMASK_ACTIVE_PLAYER;
     }
 
     switch (GetGUID().GetHigh())

src/server/game/Scripting/ScriptReloadMgr.cpp

@@ -59,6 +59,7 @@ ScriptReloadMgr* ScriptReloadMgr::instance()
 #include <future>
 #include <memory>
 #include <sstream>
+#include <thread>
 #include <type_traits>
 #include <unordered_map>
 #include <unordered_set>

src/server/game/Server/Packets/BattlePetPackets.h

@@ -133,7 +133,7 @@ namespace WorldPackets
 
             ObjectGuid PetGuid;
             std::string Name;
-            Optional<DeclinedName> DeclinedName;
+            Optional<::DeclinedName> DeclinedName;
         };
 
         class BattlePetDeletePet final : public ClientPacket

src/server/game/Server/Packets/BattlefieldPackets.h

@@ -20,6 +20,7 @@
 
 #include "Packet.h"
 #include "ObjectGuid.h"
+#include <limits>
 
 namespace WorldPackets
 {