diff --git a/sql-common/client.c b/sql-common/client.c
index 0a30ef150e1..e8ca74eba37 100644
--- a/sql-common/client.c
+++ b/sql-common/client.c
@@ -2923,7 +2923,7 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 		       uint port, const char *unix_socket,ulong client_flag)
 {
   char		buff[NAME_LEN+USERNAME_LENGTH+100];
-  int           scramble_data_len, pkt_scramble_len;
+  int           scramble_data_len, pkt_scramble_len= 0;
   char          *end,*host_info= 0, *server_version_end, *pkt_end;
   char          *scramble_data;
   const char    *scramble_plugin;
diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc
index 571a7890116..5583e9a29f1 100644
--- a/sql/sql_acl.cc
+++ b/sql/sql_acl.cc
@@ -3936,7 +3936,7 @@ bool mysql_grant(THD *thd, const char *db, List <LEX_USER> &list,
                  ulong rights, bool revoke_grant, bool is_proxy)
 {
   List_iterator <LEX_USER> str_list (list);
-  LEX_USER *Str, *tmp_Str, *proxied_user;
+  LEX_USER *Str, *tmp_Str, *proxied_user= NULL;
   char tmp_db[NAME_LEN+1];
   bool create_new_users=0;
   TABLE_LIST tables[2];
diff --git a/sql/sql_cache.cc b/sql/sql_cache.cc
index 9876c46bbb3..0dadc0f0cd4 100644
--- a/sql/sql_cache.cc
+++ b/sql/sql_cache.cc
@@ -412,7 +412,8 @@ struct Query_cache_wait_state
 
   Query_cache_wait_state(THD *thd, const char *func,
                          const char *file, unsigned int line)
-  : m_thd(thd)
+  : m_thd(thd),
+    m_proc_info(NULL)
   {
     if (m_thd)
       m_proc_info= set_thd_proc_info(m_thd,