IPAddress: allow misaligned source in constructor (#5421)

Author: d-a-v

cores/esp8266/IPAddress.cpp

@@ -22,6 +22,11 @@
 #include <Print.h>
 #include <StreamString.h>
 
+IPAddress::IPAddress(const IPAddress& from)
+{
+    ip_addr_copy(_ip, from._ip);
+}
+
 IPAddress::IPAddress() {
     _ip = *IP_ANY_TYPE; // lwIP's v4-or-v6 generic address
 }
@@ -45,7 +50,10 @@ void IPAddress::ctor32(uint32_t address) {
 
 IPAddress::IPAddress(const uint8_t *address) {
     setV4();
-    v4() = *reinterpret_cast<const uint32_t*>(address);
+    (*this)[0] = address[0];
+    (*this)[1] = address[1];
+    (*this)[2] = address[2];
+    (*this)[3] = address[3];
 }
 
 bool IPAddress::fromString(const char *address) {

cores/esp8266/IPAddress.h

@@ -72,6 +72,7 @@ class IPAddress: public Printable {
     public:
         // Constructors
         IPAddress();
+        IPAddress(const IPAddress& from);
         IPAddress(uint8_t first_octet, uint8_t second_octet, uint8_t third_octet, uint8_t fourth_octet);
         IPAddress(uint32_t address) { ctor32(address); }
         IPAddress(u32_t address) { ctor32(address); }