diff --git a/cache/lru_cache_test.cc b/cache/lru_cache_test.cc
index 6ff2151aa..1194d1b89 100644
--- a/cache/lru_cache_test.cc
+++ b/cache/lru_cache_test.cc
@@ -229,7 +229,7 @@ class TestNvmCache : public NvmCache {
   std::unique_ptr<NvmCacheHandle> Lookup(const Slice& key,
                                          const Cache::CreateCallback& create_cb,
                                          bool /*wait*/) override {
-    std::unique_ptr<TestNvmCacheHandle> nvm_handle;
+    std::unique_ptr<NvmCacheHandle> nvm_handle;
     Cache::Handle* handle = cache_->Lookup(key);
     num_lookups_++;
     if (handle) {
@@ -363,8 +363,8 @@ TEST_F(LRUCacheTest, TestNvmCache) {
                          Cache::Priority::LOW, true);
   ASSERT_NE(handle, nullptr);
   cache->Release(handle);
-  ASSERT_EQ(nvm_cache->num_inserts(), 2);
-  ASSERT_EQ(nvm_cache->num_lookups(), 1);
+  ASSERT_EQ(nvm_cache->num_inserts(), 2u);
+  ASSERT_EQ(nvm_cache->num_lookups(), 1u);
 }
 }  // namespace ROCKSDB_NAMESPACE
 
diff --git a/db/db_basic_test.cc b/db/db_basic_test.cc
index 63a225252..34f27b809 100644
--- a/db/db_basic_test.cc
+++ b/db/db_basic_test.cc
@@ -2820,6 +2820,7 @@ class DBBasicTestMultiGet : public DBTestBase {
 
     const char* Name() const override { return "MyBlockCache"; }
 
+    using Cache::Insert;
     Status Insert(const Slice& key, void* value, size_t charge,
                   void (*deleter)(const Slice& key, void* value),
                   Handle** handle = nullptr,
@@ -2828,6 +2829,7 @@ class DBBasicTestMultiGet : public DBTestBase {
       return target_->Insert(key, value, charge, deleter, handle, priority);
     }
 
+    using Cache::Lookup;
     Handle* Lookup(const Slice& key, Statistics* stats = nullptr) override {
       num_lookups_++;
       Handle* handle = target_->Lookup(key, stats);
diff --git a/db/db_block_cache_test.cc b/db/db_block_cache_test.cc
index cf6f6dfd9..a2a08abc8 100644
--- a/db/db_block_cache_test.cc
+++ b/db/db_block_cache_test.cc
@@ -446,6 +446,7 @@ class MockCache : public LRUCache {
                  false /*strict_capacity_limit*/, 0.0 /*high_pri_pool_ratio*/) {
   }
 
+  using ShardedCache::Insert;
   Status Insert(const Slice& key, void* value, size_t charge,
                 void (*deleter)(const Slice& key, void* value), Handle** handle,
                 Priority priority) override {
@@ -533,6 +534,7 @@ class LookupLiarCache : public CacheWrapper {
   explicit LookupLiarCache(std::shared_ptr<Cache> target)
       : CacheWrapper(std::move(target)) {}
 
+  using Cache::Lookup;
   Handle* Lookup(const Slice& key, Statistics* stats) override {
     if (nth_lookup_not_found_ == 1) {
       nth_lookup_not_found_ = 0;
diff --git a/include/rocksdb/cache.h b/include/rocksdb/cache.h
index 933942839..b509a1a31 100644
--- a/include/rocksdb/cache.h
+++ b/include/rocksdb/cache.h
@@ -174,7 +174,7 @@ class Cache {
   // data into a buffer. The NVM cache may decide to not store it in a
   // contiguous buffer, in which case this callback will be called multiple
   // times with increasing offset
-  typedef rocksdb::Status (*SaveToCallback)(void* obj, size_t offset,
+  typedef ROCKSDB_NAMESPACE::Status (*SaveToCallback)(void* obj, size_t offset,
                                             size_t size, void* out);
 
   // DeletionCallback is a function pointer that deletes the cached
@@ -191,8 +191,8 @@ class Cache {
   // takes in a buffer from the NVM cache and constructs an object using
   // it. The callback doesn't have ownership of the buffer and should
   // copy the contents into its own buffer.
-  typedef std::function<rocksdb::Status(void* buf, size_t size, void** out_obj,
-                                        size_t* charge)>
+  typedef std::function<ROCKSDB_NAMESPACE::Status(void* buf, size_t size,
+                                      void** out_obj, size_t* charge)>
       CreateCallback;
 
   Cache(std::shared_ptr<MemoryAllocator> allocator = nullptr)
@@ -275,7 +275,7 @@ class Cache {
                         CacheItemHelperCallback helper_cb, size_t charge,
                         Handle** handle = nullptr,
                         Priority priority = Priority::LOW) {
-    DeletionCallback delete_cb;
+    DeletionCallback delete_cb = nullptr;
     (*helper_cb)(nullptr, nullptr, &delete_cb);
     return Insert(key, value, charge, delete_cb, handle, priority);
   }