diff --git a/src/curl.cpp b/src/curl.cpp
index 80ab1d3..440e2cc 100644
--- a/src/curl.cpp
+++ b/src/curl.cpp
@@ -4003,7 +4003,7 @@ int S3fsCurl::PreMultipartPostRequest(const char* tpath, headers_t& meta, std::s
     return 0;
 }
 
-int S3fsCurl::CompleteMultipartPostRequest(const char* tpath, const std::string& upload_id, etaglist_t& parts)
+int S3fsCurl::CompleteMultipartPostRequest(const char* tpath, const std::string& upload_id, const etaglist_t& parts)
 {
     S3FS_PRN_INFO3("[tpath=%s][parts=%zu]", SAFESTRPTR(tpath), parts.size());
 
@@ -4014,7 +4014,7 @@ int S3fsCurl::CompleteMultipartPostRequest(const char* tpath, const std::string&
     // make contents
     std::string postContent;
     postContent += "<CompleteMultipartUpload>\n";
-    for(etaglist_t::iterator it = parts.begin(); it != parts.end(); ++it){
+    for(auto it = parts.begin(); it != parts.end(); ++it){
         if(it->etag.empty()){
             S3FS_PRN_ERR("%d file part is not finished uploading.", it->part_num);
             return -EIO;
diff --git a/src/curl.h b/src/curl.h
index 6bdc1bb..df59b71 100644
--- a/src/curl.h
+++ b/src/curl.h
@@ -385,7 +385,7 @@ class S3fsCurl
         int CheckBucket(const char* check_path, bool compat_dir, bool force_no_sse);
         int ListBucketRequest(const char* tpath, const char* query);
         int PreMultipartPostRequest(const char* tpath, headers_t& meta, std::string& upload_id, bool is_copy);
-        int CompleteMultipartPostRequest(const char* tpath, const std::string& upload_id, etaglist_t& parts);
+        int CompleteMultipartPostRequest(const char* tpath, const std::string& upload_id, const etaglist_t& parts);
         int UploadMultipartPostRequest(const char* tpath, int part_num, const std::string& upload_id);
         bool MixMultipartPostComplete();
         int MultipartListRequest(std::string& body);
diff --git a/src/fdcache_fdinfo.cpp b/src/fdcache_fdinfo.cpp
index 4229ffe..be5b1c2 100644
--- a/src/fdcache_fdinfo.cpp
+++ b/src/fdcache_fdinfo.cpp
@@ -697,7 +697,7 @@ bool PseudoFdInfo::CancelAllThreads()
 // [NOTE]
 // Maximum multipart upload size must be uploading boundary.
 //
-bool PseudoFdInfo::ExtractUploadPartsFromUntreatedArea(const off_t& untreated_start, const off_t& untreated_size, mp_part_list_t& to_upload_list, filepart_list_t& cancel_upload_list, off_t max_mp_size)
+bool PseudoFdInfo::ExtractUploadPartsFromUntreatedArea(off_t untreated_start, off_t untreated_size, mp_part_list_t& to_upload_list, filepart_list_t& cancel_upload_list, off_t max_mp_size)
 {
     if(untreated_start < 0 || untreated_size <= 0){
         S3FS_PRN_ERR("Parameters are wrong(untreated_start=%lld, untreated_size=%lld).", static_cast<long long int>(untreated_start), static_cast<long long int>(untreated_size));
diff --git a/src/fdcache_fdinfo.h b/src/fdcache_fdinfo.h
index efe2fbb..72d3f54 100644
--- a/src/fdcache_fdinfo.h
+++ b/src/fdcache_fdinfo.h
@@ -86,7 +86,7 @@ class PseudoFdInfo
         bool ParallelMultipartUpload(const char* path, const mp_part_list_t& mplist, bool is_copy);
         bool InsertUploadPart(off_t start, off_t size, int part_num, bool is_copy, etagpair** ppetag);
         bool CancelAllThreads();
-        bool ExtractUploadPartsFromUntreatedArea(const off_t& untreated_start, const off_t& untreated_size, mp_part_list_t& to_upload_list, filepart_list_t& cancel_upload_list, off_t max_mp_size);
+        bool ExtractUploadPartsFromUntreatedArea(off_t untreated_start, off_t untreated_size, mp_part_list_t& to_upload_list, filepart_list_t& cancel_upload_list, off_t max_mp_size);
         bool IsUploadingHasLock() const REQUIRES(upload_list_lock);
 
     public: