Anoher try to avoid GCC strict-aliasing error

runtime/bin/socket_linux.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include <errno.h>  // NOLINT
 #include <stdio.h>  // NOLINT
 #include <stdlib.h>  // NOLINT
 #include <string.h>  // NOLINT
 #include <sys/stat.h>  // NOLINT
 #include <unistd.h>  // NOLINT
 #include <netinet/tcp.h>  // NOLINT
 
 #include "bin/fdutils.h"
 #include "bin/file.h"
 #include "bin/log.h"
 #include "bin/socket.h"
 
 
 #define SOCKADDR_STORAGE_GET_PORT(addr) \
     addr.ss_family == AF_INET ? \
     ntohs(reinterpret_cast<struct sockaddr_in*>(&addr)->sin_port) : \
     ntohs(reinterpret_cast<struct sockaddr_in6*>(&addr)->sin6_port)
 
 
+typedef union {
+  struct sockaddr sa;
+  struct sockaddr_in sa_in;
+  struct sockaddr_in6 sa_in6;
+  struct sockaddr_storage sa_stor;
+} address;
+
+
 static void SetPort(sockaddr_storage* addr, int port) {
-  char* ptr = reinterpret_cast<char*>(addr);
-  if (addr->ss_family == AF_INET) {
-    reinterpret_cast<struct sockaddr_in*>(ptr)->sin_port = htons(port);
+  address* ptr = reinterpret_cast<address*>(addr);
+  if (ptr->sa_stor.ss_family == AF_INET) {
+    ptr->sa_in.sin_port = htons(port);
   } else { \
-    reinterpret_cast<struct sockaddr_in6*>(ptr)->sin6_port = htons(port);
+    ptr->sa_in6.sin6_port = htons(port);
   }
 }
 
 
 SocketAddress::SocketAddress(struct addrinfo* addrinfo) {
   ASSERT(INET6_ADDRSTRLEN >= INET_ADDRSTRLEN);
   sockaddr_in *sockaddr = reinterpret_cast<sockaddr_in *>(addrinfo->ai_addr);
   const char* result = inet_ntop(addrinfo->ai_family,
                                  &sockaddr->sin_addr,
                                  as_string_,
@@ skipping 272 matching lines @@
 bool Socket::SetNoDelay(intptr_t fd, bool enabled) {
   int on = enabled ? 1 : 0;
   return TEMP_FAILURE_RETRY(setsockopt(fd,
                                        SOL_TCP,
                                        TCP_NODELAY,
                                        reinterpret_cast<char *>(&on),
                                        sizeof(on))) == 0;
 }
 
 #endif  // defined(TARGET_OS_LINUX)