diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 9ae025b..3a550ef 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -399,7 +399,8 @@
                             PassObserver* pass_observer,
                             VariableSizedHandleScope* handles) const;
 
-  void GenerateJitDebugInfo(ArtMethod* method, debug::MethodDebugInfo method_debug_info)
+  void GenerateJitDebugInfo(ArtMethod* method,
+                            const debug::MethodDebugInfo& method_debug_info)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
   std::unique_ptr<OptimizingCompilerStats> compilation_stats_;
@@ -1406,7 +1407,8 @@
   return true;
 }
 
-void OptimizingCompiler::GenerateJitDebugInfo(ArtMethod* method, debug::MethodDebugInfo info) {
+void OptimizingCompiler::GenerateJitDebugInfo(
+    ArtMethod* method, const debug::MethodDebugInfo& info) {
   const CompilerOptions& compiler_options = GetCompilerDriver()->GetCompilerOptions();
   DCHECK(compiler_options.GenerateAnyDebugInfo());
 
diff --git a/profman/profile_assistant_test.cc b/profman/profile_assistant_test.cc
index 286b686..f9707d3 100644
--- a/profman/profile_assistant_test.cc
+++ b/profman/profile_assistant_test.cc
@@ -116,9 +116,9 @@
   void SetupBasicProfile(const std::string& id,
                          uint32_t checksum,
                          uint16_t number_of_methods,
-                         const std::vector<uint32_t> hot_methods,
-                         const std::vector<uint32_t> startup_methods,
-                         const std::vector<uint32_t> post_startup_methods,
+                         const std::vector<uint32_t>& hot_methods,
+                         const std::vector<uint32_t>& startup_methods,
+                         const std::vector<uint32_t>& post_startup_methods,
                          const ScratchFile& profile,
                          ProfileCompilationInfo* info) {
     std::string dex_location = "location1" + id;
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index befeea4..14b44dd 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -6448,7 +6448,7 @@
 // iftable must be large enough to hold all interfaces without changing its size.
 static size_t FillIfTable(ObjPtr<mirror::IfTable> iftable,
                           size_t super_ifcount,
-                          std::vector<ObjPtr<mirror::Class>> to_process)
+                          const std::vector<ObjPtr<mirror::Class>>& to_process)
     REQUIRES(Roles::uninterruptible_)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   // This is the set of all class's already in the iftable. Used to make checking if a class has
diff --git a/runtime/oat_file_manager.cc b/runtime/oat_file_manager.cc
index 1f0b265..92d2d44 100644
--- a/runtime/oat_file_manager.cc
+++ b/runtime/oat_file_manager.cc
@@ -151,7 +151,7 @@
 }
 
 std::vector<const OatFile*> OatFileManager::RegisterImageOatFiles(
-    std::vector<gc::space::ImageSpace*> spaces) {
+    const std::vector<gc::space::ImageSpace*>& spaces) {
   std::vector<const OatFile*> oat_files;
   for (gc::space::ImageSpace* space : spaces) {
     oat_files.push_back(RegisterOatFile(space->ReleaseOatFile()));
diff --git a/runtime/oat_file_manager.h b/runtime/oat_file_manager.h
index 4132b25..7d96a7a 100644
--- a/runtime/oat_file_manager.h
+++ b/runtime/oat_file_manager.h
@@ -73,7 +73,8 @@
 
   // Returns the oat files for the images, registers the oat files.
   // Takes ownership of the imagespace's underlying oat files.
-  std::vector<const OatFile*> RegisterImageOatFiles(std::vector<gc::space::ImageSpace*> spaces)
+  std::vector<const OatFile*> RegisterImageOatFiles(
+      const std::vector<gc::space::ImageSpace*>& spaces)
       REQUIRES(!Locks::oat_file_manager_lock_);
 
   // Finds or creates the oat file holding dex_location. Then loads and returns
diff --git a/runtime/subtype_check_info_test.cc b/runtime/subtype_check_info_test.cc
index 5323093..9bd135e 100644
--- a/runtime/subtype_check_info_test.cc
+++ b/runtime/subtype_check_info_test.cc
@@ -131,7 +131,7 @@
 
   // Create an SubtypeCheckInfo with the same depth, but with everything else reset.
   // Returns: SubtypeCheckInfo in the Uninitialized state.
-  static SubtypeCheckInfo CopyCleared(SubtypeCheckInfo sc) {
+  static SubtypeCheckInfo CopyCleared(const SubtypeCheckInfo& sc) {
     SubtypeCheckInfo cleared_copy{};
     cleared_copy.depth_ = sc.depth_;
     DCHECK_EQ(SubtypeCheckInfo::kUninitialized, cleared_copy.GetState());
diff --git a/runtime/trace.cc b/runtime/trace.cc
index 7e48bae..0e8d318 100644
--- a/runtime/trace.cc
+++ b/runtime/trace.cc
@@ -1124,7 +1124,7 @@
 
 void Trace::DumpThreadList(std::ostream& os) {
   Thread* self = Thread::Current();
-  for (auto it : exited_threads_) {
+  for (const auto& it : exited_threads_) {
     os << it.first << "\t" << it.second << "\n";
   }
   Locks::thread_list_lock_->AssertNotHeld(self);
diff --git a/test/004-JniTest/jni_test.cc b/test/004-JniTest/jni_test.cc
index 33a8f5b..c4eb75a 100644
--- a/test/004-JniTest/jni_test.cc
+++ b/test/004-JniTest/jni_test.cc
@@ -704,7 +704,7 @@
   }
 
  private:
-  void TestCalls(const char* declaring_class, std::vector<const char*> methods) {
+  void TestCalls(const char* declaring_class, const std::vector<const char*>& methods) {
     jmethodID new_method = env_->GetMethodID(concrete_class_, "<init>", "()V");
     jobject obj = env_->NewObject(concrete_class_, new_method);
     CHECK(!env_->ExceptionCheck());