[C++20] Enable C++20 + Fixes + FMT 9.1 (#2664)

* [CPP] Enable and build compliance with cpp20

* Windows build fix

* bump fmt version

* Updated fmt to 9.1, updated cmake minimum and verified preprocessor stuff works.

* Missing :

* Fix warning: top-level comma expression in array subscript is deprecated

* Fix warning: top-level comma expression in array subscript is deprecated

Co-authored-by: KimLS <KimLS@peqtgc.com>

common/CMakeLists.txt

@@ -1,4 +1,4 @@
-CMAKE_MINIMUM_REQUIRED(VERSION 3.2)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.12)
 
 SET(common_sources
     base_packet.cpp

common/memory_buffer.h

@@ -1,5 +1,5 @@
 /*	EQEMu: Everquest Server Emulator
-	
+
 	Copyright (C) 2001-2016 EQEMu Development Team (http://eqemulator.net)
 
 	This program is free software; you can redistribute it and/or modify
@@ -41,7 +41,7 @@ namespace EQ
 		MemoryBuffer& operator+=(const MemoryBuffer &rhs);
 		friend MemoryBuffer operator+(MemoryBuffer lhs, const MemoryBuffer& rhs) { return lhs += rhs; }
 		~MemoryBuffer();
-		
+
 		uchar& operator[](size_t pos);
 		const uchar& operator[](size_t pos) const;
 
@@ -64,20 +64,20 @@ namespace EQ
 		size_t Size() const;
 		size_t Capacity();
 		size_t Capacity() const;
-		
+
 		void Resize(size_t sz);
 		void Clear();
 		void Zero();
 
 		template<typename T>
 		void Write(T val) {
-			static_assert(std::is_pod<T>::value, "MemoryBuffer::Write<T>(T val) only works on pod and string types.");
+			static_assert(std::is_standard_layout<T>::value, "MemoryBuffer::Write<T>(T val) only works on pod and string types.");
 			Write((const char*)&val, sizeof(T));
 		}
 
 		template<typename T>
 		T Read() {
-			static_assert(std::is_pod<T>::value, "MemoryBuffer::Read<T>() only works on pod and string types.");
+			static_assert(std::is_standard_layout<T>::value, "MemoryBuffer::Read<T>() only works on pod and string types.");
 			T temp;
 			Read((uchar*)&temp, sizeof(T));
 			return temp;
@@ -102,7 +102,7 @@ namespace EQ
 			read_pos_ += len + 1;
 			return ret;
 		}
-	
+
 		void Write(const char *val, size_t len);
 		void Read(uchar *buf, size_t len);
 		void Read(char *str);
@@ -113,7 +113,7 @@ namespace EQ
 		inline size_t GetReadPosition() { return read_pos_; }
 		inline void SetReadPosition(size_t rp) { read_pos_ = rp; }
 		inline void ReadSkipBytes(size_t skip) { read_pos_ += skip; }
-		
+
 	private:
 		uchar *buffer_;
 		size_t size_;

common/repositories/character_expedition_lockouts_repository.h

@@ -75,8 +75,6 @@ public:
 		Database& db, const std::vector<uint32_t>& character_ids,
 		const std::string& expedition_name, const std::string& ordered_event_name)
 	{
-		auto joined_character_ids = fmt::join(character_ids, ",");
-
 		auto results = db.QueryDatabase(fmt::format(SQL(
 			SELECT
 				character_id,
@@ -93,9 +91,9 @@ public:
 				FIELD(character_id, {}),
 				FIELD(event_name, '{}') DESC
 		),
-			joined_character_ids,
+			fmt::join(character_ids, ","),
 			Strings::Escape(expedition_name),
-			joined_character_ids,
+			fmt::join(character_ids, ","),
 			Strings::Escape(ordered_event_name)
 		));
 

common/strings.h

@@ -44,9 +44,10 @@
 #include <tuple>
 #include <type_traits>
 
+#include <fmt/format.h>
+
 #ifndef _WIN32
 // this doesn't appear to affect linux-based systems..need feedback for _WIN64
-#include <fmt/format.h>
 
 #endif