+2014-11-06  Evgeniy Dushistov  <dushistov@mail.ru>
+
+       * plugin.cc: use lock to searialize calls of Plugin_manager::claim_file
+       * plugin.h: add lock definition
+
 2014-10-29  Han Shen  <shenhan@google.com>
            Jing Yu   <jingyu@google.com>
 
 
        ++obj)
     delete *obj;
   this->objects_.clear();
+  delete this->lock_;
 }
 
 // Load all plugin libraries.
 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
                            off_t filesize, Object* elf_object)
 {
+  bool lock_initialized = this->initialize_lock_.initialize();
+
+  gold_assert(lock_initialized);
+  Hold_lock hl(*this->lock_);
   if (this->in_replacement_phase_)
     return NULL;
 
 
       in_claim_file_handler_(false),
       options_(options), workqueue_(NULL), task_(NULL), input_objects_(NULL),
       symtab_(NULL), layout_(NULL), dirpath_(NULL), mapfile_(NULL),
-      this_blocker_(NULL), extra_search_path_()
+      this_blocker_(NULL), extra_search_path_(), lock_(NULL),
+      initialize_lock_(&lock_)
   { this->current_ = plugins_.end(); }
 
   ~Plugin_manager();
   // An extra directory to seach for the libraries passed by
   // add_input_library.
   std::string extra_search_path_;
+  Lock* lock_;
+  Initialize_lock initialize_lock_;
 };