- Fix a lot of warnings generated by -Wshorten-64-to-32

runtime/vm/ring_buffer.h

 // Copyright (c) 2014, 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.
 
 #ifndef VM_RING_BUFFER_H_
 #define VM_RING_BUFFER_H_
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 
 namespace dart {
 
 // Fixed-capacity ring buffer.
 template<typename T, int N>
 class RingBuffer {
  public:
   RingBuffer() : count_(0) { }
 
   void Add(const T& t) {
     data_[count_++ & kMask] = t;
   }
 
   // Returns the i'th most recently added element. Requires 0 <= i < Size().
   const T& Get(int i) const {
     ASSERT(0 <= i && i < Size());
     return data_[(count_ - i - 1) & kMask];
   }
 
   // Returns the number of elements currently stored in this buffer (at most N).
-  int Size() const { return Utils::Minimum(count_, static_cast<int64_t>(N)); }
+  int64_t Size() const {
+    return Utils::Minimum(count_, static_cast<int64_t>(N));
+  }
 
  private:
   static const int kMask = N - 1;
   COMPILE_ASSERT((N & kMask) == 0);
   T data_[N];
   int64_t count_;
 };
 
 }  // namespace dart
 
 #endif  // VM_RING_BUFFER_H_