Conditional jump or move depends on uninitialised value in find_stage_class, multi_source.info_logs fails in buildbot and outside

multi_source.info_logs                   w1 [ fail ]  Found warnings/errors in server log file!

        Test ended at 2017-04-27 01:10:40

line

==22085== Conditional jump or move depends on uninitialised value(s)

==22085==    at 0xB8C015: find_stage_class(unsigned int) (pfs_instr_class.cc:1080)

==22085==    by 0xBBA48A: start_stage_v1 (pfs.cc:4305)

==22085==    by 0x548882: inline_mysql_set_stage(unsigned int, char const*, int) (mysql_stage.h:65)

==22085==    by 0x559B90: THD::enter_stage(PSI_stage_info_v1 const*, char const*, char const*, unsigned int) (sql_class.h:2045)

==22085==    by 0x5E8B15: THD::exit_cond(PSI_stage_info_v1 const*, char const*, char const*, int) (sql_class.h:3018)

==22085==    by 0x573449: start_slave_thread(unsigned int, void* (*)(void*), st_mysql_mutex*, st_mysql_mutex*, st_mysql_cond*, unsigned int volatile*, unsigned long volatile*, Master_info*) (slave.cc:969)

==22085==    by 0x57379A: start_slave_threads(THD*, bool, bool, Master_info*, char const*, char const*, int) (slave.cc:1056)

==22085==    by 0x74B85B: Master_info_index::init_all_master_info() (rpl_mi.cc:1215)

==22085==    by 0x572124: init_slave() (slave.cc:475)

==22085==    by 0x551CA4: mysqld_main(int, char**) (mysqld.cc:5869)

==22085==    by 0x546D57: main (main.cc:25)