main.default fails with valgrind in buildbot and outside

main.default                             w3 [ fail ]  Found warnings/errors in server log file!

        Test ended at 2017-05-02 17:18:39

line

==6231== Thread 7:

==6231== Conditional jump or move depends on uninitialised value(s)

==6231==    at 0x6812A7: String::c_ptr() (sql_string.h:218)

==6231==    by 0x80017B: fix_vcol_expr(THD*, Virtual_column_info*) (table.cc:2710)

==6231==    by 0x80051C: fix_and_check_vcol_expr(THD*, TABLE*, Virtual_column_info*) (table.cc:2787)

==6231==    by 0x800941: unpack_vcol_info_from_frm(THD*, st_mem_root*, TABLE*, String*, Virtual_column_info**, bool*) (table.cc:2904)

==6231==    by 0x7FA401: parse_vcol_defs(THD*, st_mem_root*, TABLE*, bool*) (table.cc:1075)

==6231==    by 0x8015E3: open_table_from_share(THD*, TABLE_SHARE*, char const*, unsigned int, unsigned int, unsigned int, TABLE*, bool) (table.cc:3135)

==6231==    by 0x98BD07: ha_create_table(THD*, char const*, char const*, char const*, HA_CREATE_INFO*, st_mysql_const_unsigned_lex_string*) (handler.cc:4731)

==6231==    by 0x819A14: rea_create_table(THD*, st_mysql_const_unsigned_lex_string*, char const*, char const*, char const*, HA_CREATE_INFO*, handler*, bool) (unireg.cc:419)

==6231==    by 0x7C7014: create_table_impl(THD*, char const*, char const*, char const*, char const*, char const*, DDL_options_st, HA_CREATE_INFO*, Alter_info*, int, bool*, st_key**, unsigned int*, st_mysql_const_unsigned_lex_string*) (sql_table.cc:4878)

==6231==    by 0x7C7644: mysql_create_table_no_lock(THD*, char const*, char const*, Table_specification_st*, Alter_info*, bool*, int) (sql_table.cc:4989)

==6231==    by 0x7C78C7: mysql_create_table(THD*, TABLE_LIST*, Table_specification_st*, Alter_info*) (sql_table.cc:5052)

==6231==    by 0x6FE9F8: mysql_execute_command(THD*) (sql_parse.cc:3952)

==6231== Conditional jump or move depends on uninitialised value(s)

==6231==    at 0x4C2AE9C: strnlen (vg_replace_strmem.c:421)

==6231==    by 0x118E7BF: process_str_arg (my_vsnprintf.c:205)

==6231==    by 0x1190434: my_vsnprintf_ex (my_vsnprintf.c:626)

==6231==    by 0x111B1AC: my_error (my_error.c:121)

==6231==    by 0x800192: fix_vcol_expr(THD*, Virtual_column_info*) (table.cc:2710)

==6231==    by 0x80051C: fix_and_check_vcol_expr(THD*, TABLE*, Virtual_column_info*) (table.cc:2787)

==6231==    by 0x800941: unpack_vcol_info_from_frm(THD*, st_mem_root*, TABLE*, String*, Virtual_column_info**, bool*) (table.cc:2904)

==6231==    by 0x7FA401: parse_vcol_defs(THD*, st_mem_root*, TABLE*, bool*) (table.cc:1075)

==6231==    by 0x8015E3: open_table_from_share(THD*, TABLE_SHARE*, char const*, unsigned int, unsigned int, unsigned int, TABLE*, bool) (table.cc:3135)

==6231==    by 0x98BD07: ha_create_table(THD*, char const*, char const*, char const*, HA_CREATE_INFO*, st_mysql_const_unsigned_lex_string*) (handler.cc:4731)

==6231==    by 0x819A14: rea_create_table(THD*, st_mysql_const_unsigned_lex_string*, char const*, char const*, char const*, HA_CREATE_INFO*, handler*, bool) (unireg.cc:419)

==6231==    by 0x7C7014: create_table_impl(THD*, char const*, char const*, char const*, char const*, char const*, DDL_options_st, HA_CREATE_INFO*, Alter_info*, int, bool*, st_key**, unsigned int*, st_mysql_const_unsigned_lex_string*) (sql_table.cc:4878)