diff --git a/db/compaction/compaction_picker_test.cc b/db/compaction/compaction_picker_test.cc
index c75b14a7946..a44b35b096f 100644
--- a/db/compaction/compaction_picker_test.cc
+++ b/db/compaction/compaction_picker_test.cc
@@ -516,13 +516,11 @@ TEST_F(CompactionPickerTest, NeedsCompactionFIFO) {
 
   // verify whether compaction is needed based on the current
   // size of L0 files.
-  uint64_t current_size = 0;
   for (int i = 1; i <= kFileCount; ++i) {
     NewVersionStorage(1, kCompactionStyleFIFO);
     Add(0, i, ToString((i + 100) * 1000).c_str(),
-        ToString((i + 100) * 1000 + 999).c_str(),
-        kFileSize, 0, i * 100, i * 100 + 99);
-    current_size += kFileSize;
+        ToString((i + 100) * 1000 + 999).c_str(), kFileSize, 0, i * 100,
+        i * 100 + 99);
     UpdateVersionStorageInfo();
     ASSERT_EQ(fifo_compaction_picker.NeedsCompaction(vstorage_.get()),
               vstorage_->CompactionScore(0) >= 1);
diff --git a/db/db_test2.cc b/db/db_test2.cc
index a7b3d2b4aba..33e7cc20eb5 100644
--- a/db/db_test2.cc
+++ b/db/db_test2.cc
@@ -2199,7 +2199,6 @@ TEST_F(DBTest2, ReadAmpBitmapLiveInCacheAfterDBClose) {
     Close();
     Reopen(options);
 
-    uint64_t total_useful_bytes = 0;
     std::set<int> read_keys;
     std::string value;
     // Iter1: Read half the DB, Read even keys
@@ -2210,8 +2209,6 @@ TEST_F(DBTest2, ReadAmpBitmapLiveInCacheAfterDBClose) {
 
       if (read_keys.find(i) == read_keys.end()) {
         auto internal_key = InternalKey(key, 0, ValueType::kTypeValue);
-        total_useful_bytes +=
-            GetEncodedEntrySize(internal_key.size(), value.size());
         read_keys.insert(i);
       }
     }
@@ -2237,8 +2234,6 @@ TEST_F(DBTest2, ReadAmpBitmapLiveInCacheAfterDBClose) {
 
       if (read_keys.find(i) == read_keys.end()) {
         auto internal_key = InternalKey(key, 0, ValueType::kTypeValue);
-        total_useful_bytes +=
-            GetEncodedEntrySize(internal_key.size(), value.size());
         read_keys.insert(i);
       }
     }
diff --git a/options/db_options.h b/options/db_options.h
index 01c737bc4c3..39ebf680db6 100644
--- a/options/db_options.h
+++ b/options/db_options.h
@@ -87,7 +87,6 @@ struct ImmutableDBOptions {
 
 struct MutableDBOptions {
   MutableDBOptions();
-  explicit MutableDBOptions(const MutableDBOptions& options) = default;
   explicit MutableDBOptions(const DBOptions& options);
 
   void Dump(Logger* log) const;
diff --git a/utilities/env_mirror.cc b/utilities/env_mirror.cc
index b6cbd69ecce..76a8d14d8b8 100644
--- a/utilities/env_mirror.cc
+++ b/utilities/env_mirror.cc
@@ -27,13 +27,17 @@ class SequentialFileMirror : public SequentialFile {
     if (as == Status::OK()) {
       char* bscratch = new char[n];
       Slice bslice;
+#ifndef NDEBUG
       size_t off = 0;
+#endif
       size_t left = aslice.size();
       while (left) {
         Status bs = b_->Read(left, &bslice, bscratch);
+#ifndef NDEBUG
         assert(as == bs);
         assert(memcmp(bscratch, scratch + off, bslice.size()) == 0);
         off += bslice.size();
+#endif
         left -= bslice.size();
       }
       delete[] bscratch;