diff --git a/examples/libaria2ex.cc b/examples/libaria2ex.cc
index e0200034..c22ac606 100644
--- a/examples/libaria2ex.cc
+++ b/examples/libaria2ex.cc
@@ -41,7 +41,7 @@
 #include <aria2/aria2.h>
 
 int downloadEventCallback(aria2::Session* session, aria2::DownloadEvent event,
-                          const aria2::A2Gid& gid, void* userData)
+                          aria2::A2Gid gid, void* userData)
 {
   switch(event) {
   case aria2::EVENT_ON_DOWNLOAD_COMPLETE:
diff --git a/src/KeepRunningCommand.cc b/src/KeepRunningCommand.cc
index 995f3027..af15ce3c 100644
--- a/src/KeepRunningCommand.cc
+++ b/src/KeepRunningCommand.cc
@@ -52,7 +52,7 @@ bool KeepRunningCommand::execute()
   if(e_->isHaltRequested()) {
     return true;
   }
-  e_->addCommand(this);
+  e_->addCommand(std::unique_ptr<Command>(this));
   return false;
 }
 
diff --git a/src/aria2api.cc b/src/aria2api.cc
index a9a1e131..980e3c45 100644
--- a/src/aria2api.cc
+++ b/src/aria2api.cc
@@ -128,7 +128,7 @@ Session* sessionNew(const KeyVals& options, const SessionConfig& config)
     if(config.keepRunning) {
       e->getRequestGroupMan()->setKeepRunning(true);
       // Add command to make aria2 keep event polling
-      e->addCommand(new KeepRunningCommand(e->newCUID(), e.get()));
+      e->addCommand(make_unique<KeepRunningCommand>(e->newCUID(), e.get()));
     }
     if(config.downloadEventCallback) {
       std::shared_ptr<DownloadEventListener> listener