Created by: qingqing01

If the batch size in one mini-batch is smaller than the trainer_count and there is static parameter in the network, the code will crash. The error is as follows:

*** Aborted at 1498592614 (unix time) try "date -d @1498592614" if you are using GNU date ***

PC: @                0x0 (unknown)

*** SIGSEGV (@0x29) received by PID 12513 (TID 0x7f8ec692b700) from PID 41; stack trace: ***

    @       0x318b20f500 (unknown)

    @     0x7f8eea1ee173 paddle::BaseMatrixT<>::add()

    @     0x7f8eea1311be paddle::TrainerThread::gradCollectThread()

    @     0x7f8ee98002d0 execute_native_thread_routine

    @       0x318b207851 (unknown)

    @       0x318aee767d (unknown)

    @                0x0 (unknown)