diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index cb1aabf79e5..0a0d3ca034e 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -2073,7 +2073,7 @@ bool THD::store_globals()
   */
   mysys_var->id= thread_id;
 #ifdef __NR_gettid
-  os_thread_id= syscall(__NR_gettid);
+  os_thread_id= (uint32)syscall(__NR_gettid);
 #else
   os_thread_id= 0;
 #endif
diff --git a/sql/sql_class.h b/sql/sql_class.h
index f12281657f5..58698e91a1d 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -2630,7 +2630,7 @@ public:
   ulong      query_plan_fsort_passes; 
   pthread_t  real_id;                           /* For debugging */
   my_thread_id  thread_id;
-  pid_t      os_thread_id;
+  uint32      os_thread_id;
   uint	     tmp_table, global_disable_checkpoint;
   uint	     server_status,open_options;
   enum enum_thread_type system_thread;
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index 42da649e3d7..f64c30b88f5 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -2334,7 +2334,7 @@ public:
   { TRASH(ptr, size); }
 
   ulong thread_id;
-  ulong os_thread_id;
+  uint32 os_thread_id;
   ulonglong start_time;
   uint   command;
   const char *user,*host,*db,*proc_info,*state_info;