Fix warnings on Win64.

src/platform-win32.cc

Index: src/platform-win32.cc
diff --git a/src/platform-win32.cc b/src/platform-win32.cc
index d1f53194fb48d34412db83e0883032f57036d119..1ec4d6744200436105c2113ca9aa49c052d3c16b 100644
--- a/src/platform-win32.cc
+++ b/src/platform-win32.cc
@@ -839,7 +839,7 @@ void* OS::Allocate(const size_t requested,
                    size_t* allocated,
                    bool is_executable) {
   // VirtualAlloc rounds allocated size to page size automatically.
-  size_t msize = RoundUp(requested, GetPageSize());
+  size_t msize = RoundUp(requested, static_cast<int>(GetPageSize()));
 
   // Windows XP SP2 allows Data Excution Prevention (DEP).
   int prot = is_executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
@@ -852,7 +852,7 @@ void* OS::Allocate(const size_t requested,
   ASSERT(IsAligned(reinterpret_cast<size_t>(mbase), OS::AllocateAlignment()));
 
   *allocated = msize;
-  UpdateAllocatedSpaceLimits(mbase, msize);
+  UpdateAllocatedSpaceLimits(mbase, static_cast<int>(msize));
   return mbase;
 }
 
@@ -1361,7 +1361,7 @@ bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
     return false;
   }
 
-  UpdateAllocatedSpaceLimits(address, size);
+  UpdateAllocatedSpaceLimits(address, static_cast<int>(size));
   return true;
 }
 
@@ -1689,7 +1689,9 @@ bool Win32Socket::Connect(const char* host, const char* port) {
   }
 
   // Connect.
-  status = connect(socket_, result->ai_addr, result->ai_addrlen);
+  status = connect(socket_,
+                   result->ai_addr,
+                   static_cast<int>(result->ai_addrlen));
   freeaddrinfo(result);
   return status == 0;
 }