message: Make CCoinsViewCache's copy constructor private
  It is easily confused with CCoinsViewCache(CCoinsView*), which creates a sub-cache, but instead of creating a sub-cache, the copy constructor would copy the original and use that original's base, defeating the intended isolation.
  Coming from upstream@228d2385254ee136ef64d229a414fdd7cefea9a0
diff: @@ -474,6 +474,11 @@ public:
  private:
  CCoinsMap::iterator FetchCoins(const uint256& txid);
  CCoinsMap::const_iterator FetchCoins(const uint256& txid) const;
  +
  + /**
  + * By making the copy constructor private, we prevent accidentally using it when one intends to create a cache on top of a base cache.
  + */
  + CCoinsViewCache(const CCoinsViewCache &);
  };
  #endif // BITCOIN_COINS_H
  