BUG#17947: Crash when REBUILD PARTITION syntax error

mysql-test/r/partition.result:
  New test case
mysql-test/t/partition.test:
  New test case
sql/sql_yacc.yy:
  Ridiculuos small bug in parser

mysql-test/r/partition.result

@@ -422,4 +422,10 @@ partition_name	partition_description	table_rows
 x123	11,12	1
 x234	NULL,1	1
 drop table t1;
+create table t1 (a int)
+partition by list (a)
+(partition p0 values in (1));
+alter table t1 rebuild partition;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
+drop table t1;
 End of 5.1 tests

mysql-test/t/partition.test

@@ -540,4 +540,16 @@ select partition_name, partition_description, table_rows
 from information_schema.partitions where table_schema ='test';
 drop table t1;
 
+#
+# BUG 17947 Crash with REBUILD PARTITION
+#
+create table t1 (a int)
+partition by list (a)
+(partition p0 values in (1));
+
+--error 1064
+alter table t1 rebuild partition;
+
+drop table t1;
+
 --echo End of 5.1 tests

sql/sql_yacc.yy

@@ -5024,7 +5024,7 @@ alter_commands:
         ;
 
 all_or_alt_part_name_list:
-        | ALL
+        ALL
         {
 	  Lex->alter_info.flags|= ALTER_ALL_PARTITION;
         }