[architecture] Fix compiler warnings in can message, more constexpr

Fix deprecated warning about implicitly-declared copy constructor with
custom assignment operator.

Author: chris-durand

src/modm/architecture/interface/can_message.hpp.in

@@ -26,90 +26,95 @@ namespace modm::can
 /// @ingroup modm_architecture_can
 struct Message
 {
-	inline Message(uint32_t inIdentifier = 0, uint8_t inLength = 0) :
+	constexpr Message(uint32_t inIdentifier = 0, uint8_t inLength = 0) :
 		identifier(inIdentifier), flags()
 	{
         setLength(inLength);
 	}
 
-	inline Message(uint32_t inIdentifier, uint8_t inLength, const uint64_t &inData, bool extended = false) :
+	constexpr Message(uint32_t inIdentifier, uint8_t inLength, const uint64_t &inData, bool extended = false) :
         Message(inIdentifier, std::min(inLength, uint8_t(8)))
 	{
 		flags.extended = extended;
-		const uint8_t *inDataB = reinterpret_cast<const uint8_t *>(&inData);
 		for (uint8_t ii = 0; ii < length; ++ii)
- 			data[ii] = inDataB[length - ii - 1];
+			data[ii] = inData >> ((7 - ii - (8 - length)) * 8);
 	}
 
-	inline Message(uint32_t inIdentifier, uint8_t inLength, const uint8_t *inData, bool extended = false) :
+	constexpr Message(uint32_t inIdentifier, uint8_t inLength, const uint8_t *inData, bool extended = false) :
 		Message(inIdentifier, inLength)
 	{
 		flags.extended = extended;
 		for (uint8_t ii = 0; ii < length; ++ii)
  			data[ii] = inData[ii];
 	}
 
-	inline uint32_t
+	constexpr Message(const modm::can::Message& rhs)
+		: identifier{rhs.identifier}, flags{rhs.flags}, dlc{rhs.dlc}, length{rhs.length}
+	{
+		std::copy(std::begin(rhs.data), std::end(rhs.data), std::begin(data));
+	}
+
+	constexpr uint32_t
 	getIdentifier() const
 	{
 		return identifier;
 	}
 
-	inline void
+	constexpr void
 	setIdentifier(uint32_t id)
 	{
 		identifier = id;
 	}
 
-	inline constexpr uint8_t
+	constexpr uint8_t
 	getCapacity() const
 	{
 		return capacity;
 	}
 
-	inline void
+	constexpr void
 	setFlexibleData(bool fd = true)
 	{
 		flags.fd = fd;
 	}
 
-	inline bool
+	constexpr bool
 	isFlexibleData() const
 	{
 		return (flags.fd != 0);
 	}
 
-	inline bool
+	constexpr bool
 	isBitRateSwitching() const
 	{
 		return (flags.brs != 0);
 	}
 
-	inline void
+	constexpr void
 	setExtended(bool extended = true)
 	{
 		flags.extended = (extended) ? 1 : 0;
 	}
 
-	inline bool
+	constexpr bool
 	isExtended() const
 	{
 		return (flags.extended != 0);
 	}
 
-	inline void
+	constexpr void
 	setRemoteTransmitRequest(bool rtr = true)
 	{
 		flags.rtr = (rtr) ? 1 : 0;
 	}
 
-	inline bool
+	constexpr bool
 	isRemoteTransmitRequest() const
 	{
 		return (flags.rtr != 0);
 	}
 
-	inline void
+	constexpr void
 	setDataLengthCode(uint8_t inDlc)
 	{
 		while (dlcConversionTable[inDlc] > capacity) inDlc--;
@@ -119,7 +124,7 @@ struct Message
 		if (dlc > 8) setFlexibleData();
 	}
 
-	inline void
+	constexpr void
 	setLength(uint8_t inLength)
 	{
 		if constexpr (capacity <= 8)
@@ -134,13 +139,13 @@ struct Message
 		}
 	}
 
-	inline uint8_t
+	constexpr uint8_t
 	getLength() const
 	{
 		return length;
 	}
 
-	inline uint8_t
+	constexpr uint8_t
 	getDataLengthCode() const
 	{
 		return dlc;
@@ -153,7 +158,7 @@ public:
 	uint32_t identifier;
 	struct Flags
 	{
-		Flags() :
+		constexpr Flags() :
 			fd(0), brs(0), rtr(0), extended(1)
 		{
 		}
@@ -165,10 +170,10 @@ public:
 	} flags;
 	uint8_t dlc;
 	uint8_t length;
-	uint8_t modm_aligned(4) data[capacity];
+	uint8_t modm_aligned(4) data[capacity]{};
 
 public:
-	inline bool
+	constexpr bool
 	operator == (const modm::can::Message& rhs) const
 	{
 		return ((this->identifier     == rhs.identifier) and
@@ -181,7 +186,7 @@ public:
 				std::equal(data, data + getLength(), rhs.data));
 	}
 
-	inline void
+	constexpr modm::can::Message&
 	operator = (const modm::can::Message& rhs)
 	{
 		this->identifier     = rhs.identifier;
@@ -192,9 +197,10 @@ public:
 		this->flags.rtr      = rhs.flags.rtr;
 		this->flags.extended = rhs.flags.extended;
 		std::copy(std::begin(rhs.data), std::end(rhs.data), std::begin(this->data));
+		return *this;
 	}
 
-	inline bool
+	constexpr bool
 	operator < (const modm::can::Message& rhs) const
 	{
 		return (this->identifier << (this->flags.extended ? 0 : 18))