crash when query aggregation with where

[actiontech-bot]

Raised by: @FlyingMao
Steps:

1. sysbench query: select sum(id) from sbtest1 where id between a and a+3; (a is random number between 1-50000000)
2. run sysbench:

./sysbench --test=/usr/local/sysbench-1.0/db/select32.lua --mysql-user=test --mysql-password=test --mysql-port=8066 --mysql-host=10.186.23.70 --oltp_auto_inc=off --max-time=300 --max-requests=0 --report-interval=10 --num-threads=1 run

3. after a while, dble crashed: Error in Java ：double free or cprruption(out):0x00007fcc9c121360

[actiontech-bot]

by @yanhuqing666

Caused by thread-safe, threads of aggregation handling will release same memory address.