Fix compile errors on Mac

Summary: https://phabricator.fb.com/P11372644

Test Plan: compiles

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18873

db/db_impl.cc

@@ -3563,7 +3563,7 @@ Iterator* DBImpl::NewIterator(const ReadOptions& options,
     return nullptr;
 #else
     // TODO(ljin): remove tailing iterator
-    auto iter = new ForwardIterator(env_, this, options, cfd);
+    auto iter = new ForwardIterator(this, options, cfd);
     return NewDBIterator(env_, *cfd->options(), cfd->user_comparator(), iter,
                          kMaxSequenceNumber);
 // return new TailingIterator(env_, this, options, cfd);

db/db_iter.cc

@@ -478,7 +478,7 @@ Iterator* NewDBIterator(Env* env, const Options& options,
                     false);
 }
 
-ArenaWrappedDBIter::~ArenaWrappedDBIter() { db_iter_->~Iterator(); }
+ArenaWrappedDBIter::~ArenaWrappedDBIter() { db_iter_->~DBIter(); }
 
 void ArenaWrappedDBIter::SetDBIter(DBIter* iter) { db_iter_ = iter; }
 

db/forward_iterator.cc

@@ -101,10 +101,9 @@ class LevelIterator : public Iterator {
   std::unique_ptr<Iterator> file_iter_;
 };
 
-ForwardIterator::ForwardIterator(Env* const env, DBImpl* db,
-    const ReadOptions& read_options, ColumnFamilyData* cfd)
+ForwardIterator::ForwardIterator(DBImpl* db, const ReadOptions& read_options,
+                                 ColumnFamilyData* cfd)
     : db_(db),
-      env_(env),
       read_options_(read_options),
       cfd_(cfd),
       prefix_extractor_(cfd->options()->prefix_extractor.get()),

db/forward_iterator.h

@@ -22,7 +22,7 @@ class Env;
 struct SuperVersion;
 class ColumnFamilyData;
 class LevelIterator;
-class FileMetaData;
+struct FileMetaData;
 
 class MinIterComparator {
  public:
@@ -49,8 +49,8 @@ typedef std::priority_queue<Iterator*,
  */
 class ForwardIterator : public Iterator {
  public:
-  ForwardIterator(Env* const env, DBImpl* db, const ReadOptions& read_options,
-             ColumnFamilyData* cfd);
+  ForwardIterator(DBImpl* db, const ReadOptions& read_options,
+                  ColumnFamilyData* cfd);
   virtual ~ForwardIterator();
 
   void SeekToLast() override {
@@ -81,7 +81,6 @@ class ForwardIterator : public Iterator {
     uint32_t left, uint32_t right);
 
   DBImpl* const db_;
-  Env* const env_;
   const ReadOptions read_options_;
   ColumnFamilyData* const cfd_;
   const SliceTransform* const prefix_extractor_;