diff --git a/mysql-test/r/sp-bugs.result b/mysql-test/r/sp-bugs.result
new file mode 100644
index 00000000000..14c5311bbe5
--- /dev/null
+++ b/mysql-test/r/sp-bugs.result
@@ -0,0 +1,47 @@
+#
+# Bug #47412: Valgrind warnings / user can read uninitalized memory
+# using SP variables
+#
+CREATE SCHEMA testdb;
+USE testdb;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+RETURN f_not_exists () ;
+END|
+CREATE PROCEDURE p3 ( arg1 VARCHAR(32) )
+BEGIN
+CALL p_not_exists ( );
+END|
+# should not return valgrind warnings
+CALL p3 ( f2 () );
+ERROR 42000: PROCEDURE testdb.p_not_exists does not exist
+DROP SCHEMA testdb;
+CREATE SCHEMA testdb;
+USE testdb;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+RETURN f_not_exists () ;
+END|
+CREATE PROCEDURE p3 ( arg2 INTEGER )
+BEGIN
+CALL p_not_exists ( );
+END|
+# should not return valgrind warnings
+CALL p3 ( f2 () );
+ERROR 42000: PROCEDURE testdb.p_not_exists does not exist
+DROP SCHEMA testdb;
+CREATE SCHEMA testdb;
+USE testdb;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+RETURN f_not_exists () ;
+END|
+# should not return valgrind warnings
+SELECT f2 ();
+f2 ()
+NULL
+DROP SCHEMA testdb;
+End of 5.1 tests
diff --git a/mysql-test/t/sp-bugs.test b/mysql-test/t/sp-bugs.test
new file mode 100644
index 00000000000..7b94e65a5e9
--- /dev/null
+++ b/mysql-test/t/sp-bugs.test
@@ -0,0 +1,61 @@
+# Test file for stored procedure bugfixes
+
+--echo #
+--echo # Bug #47412: Valgrind warnings / user can read uninitalized memory
+--echo # using SP variables
+--echo #
+
+CREATE SCHEMA testdb;
+USE testdb;
+DELIMITER |;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+   DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+   RETURN f_not_exists () ;
+END|
+CREATE PROCEDURE p3 ( arg1 VARCHAR(32) )
+BEGIN
+   CALL p_not_exists ( );
+END|
+DELIMITER ;|
+--echo # should not return valgrind warnings
+--error ER_SP_DOES_NOT_EXIST
+CALL p3 ( f2 () );
+
+DROP SCHEMA testdb;
+
+CREATE SCHEMA testdb;
+USE testdb;
+DELIMITER |;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+   DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+   RETURN f_not_exists () ;
+END|
+CREATE PROCEDURE p3 ( arg2 INTEGER )
+BEGIN
+   CALL p_not_exists ( );
+END|
+DELIMITER ;|
+--echo # should not return valgrind warnings
+--error ER_SP_DOES_NOT_EXIST
+CALL p3 ( f2 () );
+
+DROP SCHEMA testdb;
+
+CREATE SCHEMA testdb;
+USE testdb;
+DELIMITER |;
+CREATE FUNCTION f2 () RETURNS INTEGER
+BEGIN
+   DECLARE CONTINUE HANDLER FOR SQLSTATE '42000' SET @aux = 1;
+   RETURN f_not_exists () ;
+END|
+DELIMITER ;|
+--echo # should not return valgrind warnings
+SELECT f2 ();
+
+DROP SCHEMA testdb;
+
+
+--echo End of 5.1 tests
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 78b3df525f5..f0c858cc50a 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -334,16 +334,18 @@ bool
 sp_eval_expr(THD *thd, Field *result_field, Item **expr_item_ptr)
 {
   Item *expr_item;
+  enum_check_fields save_count_cuted_fields= thd->count_cuted_fields;
+  bool save_abort_on_warning= thd->abort_on_warning;
+  bool save_stmt_modified_non_trans_table= 
+    thd->transaction.stmt.modified_non_trans_table;
 
   DBUG_ENTER("sp_eval_expr");
 
   if (!*expr_item_ptr)
-    DBUG_RETURN(TRUE);
+    goto error;
 
   if (!(expr_item= sp_prepare_func_item(thd, expr_item_ptr)))
-    DBUG_RETURN(TRUE);
-
-  bool err_status= FALSE;
+    goto error;
 
   /*
     Set THD flags to emit warnings/errors in case of overflow/type errors
@@ -352,10 +354,6 @@ sp_eval_expr(THD *thd, Field *result_field, Item **expr_item_ptr)
     Save original values and restore them after save.
   */
   
-  enum_check_fields save_count_cuted_fields= thd->count_cuted_fields;
-  bool save_abort_on_warning= thd->abort_on_warning;
-  bool save_stmt_modified_non_trans_table= thd->transaction.stmt.modified_non_trans_table;
-
   thd->count_cuted_fields= CHECK_FIELD_ERROR_FOR_NULL;
   thd->abort_on_warning=
     thd->variables.sql_mode &
@@ -370,13 +368,18 @@ sp_eval_expr(THD *thd, Field *result_field, Item **expr_item_ptr)
   thd->abort_on_warning= save_abort_on_warning;
   thd->transaction.stmt.modified_non_trans_table= save_stmt_modified_non_trans_table;
 
-  if (thd->is_error())
-  {
-    /* Return error status if something went wrong. */
-    err_status= TRUE;
-  }
+  if (!thd->is_error())
+    DBUG_RETURN(FALSE);
 
-  DBUG_RETURN(err_status);
+error:
+  /*
+    In case of error during evaluation, leave the result field set to NULL.
+    Sic: we can't do it in the beginning of the function because the 
+    result field might be needed for its own re-evaluation, e.g. case of 
+    set x = x + 1;
+  */
+  result_field->set_null();
+  DBUG_RETURN (TRUE);
 }