Avoid heap allocations in IPAddress

net/quic/platform/impl/quic_ip_address_impl.cc

Index: net/quic/platform/impl/quic_ip_address_impl.cc
diff --git a/net/quic/platform/impl/quic_ip_address_impl.cc b/net/quic/platform/impl/quic_ip_address_impl.cc
index e0c58f14ec87d4601c10b8d955831e48b3ff2f29..6dd60845ceb00ecd7377ecfddea76b1896a86100 100644
--- a/net/quic/platform/impl/quic_ip_address_impl.cc
+++ b/net/quic/platform/impl/quic_ip_address_impl.cc
@@ -4,6 +4,7 @@
 
 #include "net/quic/platform/impl/quic_ip_address_impl.h"
 
+#include "base/containers/stack_container.h"
 #include "net/base/address_family.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
 
@@ -107,9 +108,10 @@ bool QuicIpAddressImpl::FromPackedString(const char* data, size_t length) {
     QUIC_BUG << "Invalid packed IP address of length " << length;
     return false;
   }
-  std::vector<uint8_t> ip(length);
+  base::StackVector<uint8_t, 16> ip;
+  ip->resize(length);
   memcpy(&ip[0], data, length);
-  ip_address_ = IPAddress(ip);
+  ip_address_ = IPAddress(ip->data(), ip->size());

[eroman, 2017/05/19 22:00:07]

Delete the three lines above, and change this one to:

ip_address_ = IPAddress(data, length);

(Doesn't seem like the memcpy is necessary).

[Ryan Hamilton, 2017/05/20 03:21:44]

Done. (needs a reinterpret_cast though. Thanks, C++)

   return true;
 }