diff --git a/db/compaction_job.cc b/db/compaction_job.cc
index c67aa9153162fef4da13dbab0208d4530c651eb8..fafbf81912e7b10265a6a1037f2fa13283072b50 100644
--- a/db/compaction_job.cc
+++ b/db/compaction_job.cc
@@ -1632,7 +1632,8 @@ void CompactionJob::ProcessGarbageCollection(SubcompactionState* sub_compact) {
                                       inheritance_chain.end()),
                           inheritance_chain.end());
   Status s = FinishCompactionOutputFile(status, sub_compact, nullptr,
-                                        nullptr, {}, inheritance_chain);
+                                        nullptr, std::unordered_set<uint64_t>(),
+                                        inheritance_chain);
   if (status.ok()) {
     status = s;
   }
diff --git a/db/version_builder.cc b/db/version_builder.cc
index f44320a10c85872960661a60d6a34d840415a1d4..21fb583f407162df842054732c5cb30cc50bd32b 100644
--- a/db/version_builder.cc
+++ b/db/version_builder.cc
@@ -87,8 +87,8 @@ class VersionBuilder::Rep {
     std::unordered_map<uint64_t, FileMetaData*> added_files;
   };
   struct DependenceItem {
-    size_t is_dependence;
-    size_t is_skip_gc;
+    size_t dependence_version;
+    size_t skip_gc_version;
     int level;
     FileMetaData* f;
   };
@@ -245,9 +245,9 @@ class VersionBuilder::Rep {
         continue;
       }
       auto& item = find->second;
-      item.is_dependence = dependence_version_;
+      item.dependence_version = dependence_version_;
       if (recursive) {
-        item.is_skip_gc = dependence_version_;
+        item.skip_gc_version = dependence_version_;
         SetDependence(item.f, item.f->prop.purpose == kMapSst, check_error);
       }
     }
@@ -261,9 +261,9 @@ class VersionBuilder::Rep {
       }
       assert(dependence_map_.count(file_number) > 0);
       auto& item = dependence_map_[file_number];
-      item.is_skip_gc = dependence_version_;
+      item.skip_gc_version = dependence_version_;
       if (item.level < 0) {
-        item.is_dependence = dependence_version_;
+        item.dependence_version = dependence_version_;
       }
       if (item.f->prop.purpose == kMapSst) {
         SetDependence(item.f, true, check_error);
@@ -273,7 +273,7 @@ class VersionBuilder::Rep {
     }
     for (auto it = dependence_map_.begin(); it != dependence_map_.end(); ) {
       auto& item = it->second;
-      if (item.is_dependence == dependence_version_ || item.level >= 0) {
+      if (item.dependence_version == dependence_version_ || item.level >= 0) {
         assert(inheritance_counter_.count(item.f->fd.GetNumber()) == 0);
         ++it;
       } else {
@@ -563,7 +563,7 @@ class VersionBuilder::Rep {
     }
     for (auto& pair : dependence_map_) {
       auto& item = pair.second;
-      if (item.is_dependence == dependence_version_ && item.level == -1) {
+      if (item.dependence_version == dependence_version_ && item.level == -1) {
         auto find = delta_antiquation_.find(pair.first);
         if (find != delta_antiquation_.end()) {
           item.f->num_antiquation += find->second;
@@ -577,8 +577,8 @@ class VersionBuilder::Rep {
         return false;
       }
       auto& item = find->second;
-      file_metadata->is_skip_gc |= item.is_skip_gc;
-      return item.is_dependence == dependence_version_;
+      file_metadata->is_skip_gc |= item.skip_gc_version == dependence_version_;
+      return item.dependence_version == dependence_version_;
     };
     vstorage->ShrinkDependenceMap(&exists, c_style_callback(exists));
     vstorage->set_read_amplification(read_amp);
@@ -601,7 +601,7 @@ class VersionBuilder::Rep {
     }
     for (auto& pair : dependence_map_) {
       auto& item = pair.second;
-      if (item.is_dependence == dependence_version_ && item.level == -1) {
+      if (item.dependence_version == dependence_version_ && item.level == -1) {
         files_meta.emplace_back(item.f, -1);
       }
     }
diff --git a/db/version_set.cc b/db/version_set.cc
index 7661577e481c4bce71aa58a978a6e545854de399..fee5be67817ac8237e9d670b0deb7c7d7f52398d 100644
--- a/db/version_set.cc
+++ b/db/version_set.cc
@@ -1206,7 +1206,7 @@ Status Version::inplace_decode(LazySlice* slice, LazySliceRep* rep) const {
   Slice user_key(reinterpret_cast<const char*>(rep->data[0]), rep->data[1]);
   uint64_t sequence = rep->data[2];
   uint64_t file_number = slice->file_number();
-  auto dependence_map = storage_info_.dependence_map();
+  auto& dependence_map = storage_info_.dependence_map();
   assert(dependence_map.count(file_number) > 0);
   const FileMetaData* file_metadata = dependence_map.find(file_number)->second;
   bool value_found = false;
@@ -1240,7 +1240,7 @@ void Version::TransToCombined(const Slice& user_key, uint64_t sequence,
     return;
   }
   uint64_t file_number = SeparateHelper::DecodeFileNumber(value);
-  auto dependence_map = storage_info_.dependence_map();
+  auto& dependence_map = storage_info_.dependence_map();
   auto find = dependence_map.find(file_number);
   if (find == dependence_map.end()) {
     value.reset(Status::Corruption("Separate value dependence missing"));