vowpal wabbit初始化中的内存泄漏

Question

我们有一个现有的C项目，我们正在使用vowpal wabbit。我们的用例是如果模型目录中更新的新模型重新加载模型，但每次初始化后我们都会遇到内存泄漏（在valgrind中）。

内存泄漏堆栈跟踪（来自valgrind）和代码剪切在下面。

==31962== 7,093,114 (104 direct, 7,093,010 indirect) bytes in 1 blocks are definitely lost in loss record 1,655 of 1,660
==31962==    at 0x4A075FC: operator new(unsigned long) (vg_replace_malloc.c:298)
==31962==    by 0x4F59F4D: boost::program_options::options_description::add(boost::program_options::options_description const&) (in /usr/lib64/libboost_program_options.so.1.59.0)
==31962==    by 0x5AAB82: add_options(vw&) (in testDebug)
==31962==    by 0x5BC95E: parse_source(vw&) (in testDebug)
==31962==    by 0x5BD877: parse_sources(vw&, io_buf&, bool) (in testDebug)
==31962==    by 0x5BE23D: VW::initialize(int, char**, io_buf*, bool, void (*)(void*, std::string const&), void*) (in testDebug)
==31962==    by 0x5BE4FA: VW::initialize(std::string, io_buf*, bool, void (*)(void*, std::string const&), void*) (in testDebug)
==31962==    by 0x53D658: load_vw_model_from_file (vw_predict_model.cpp:296)
==31962==    by 0x30858077F0: start_thread (in /lib64/libpthread-2.12.so)
==31962==    by 0x30854E570C: clone (in /lib64/libc-2.12.so

我的代码剪断了 -

//Declaration
vw* model;
pthread_rwlock_t vw_pmodel_rwlock = PTHREAD_RWLOCK_INITIALIZER;


//getting prediction 
double predict_vw_probability(string  vw_string) {
    double prob=-1.0;
    if (vw_string.length() > 0) {
        pthread_rwlock_rdlock(&vw_pmodel_rwlock);
        example *vec2 = VW::read_example(*model,vw_string);
        model->learn(vec2);
        prob = vec2->pred.prob;
        VW::finish_example(*model, vec2);
        pthread_rwlock_unlock(&vw_pmodel_rwlock);
    }
    return prob;
}

void load_vw_model_from_file(const char* model_file_path) {

    pthread_rwlock_wrlock(&vw_pmodel_rwlock);
    //destroying old model
    if (model != NULL) {
        VW::finish(*model);
    }
    char *vw_model_tem;
    asprintf(&vw_model_tem, "--link logistic --loss_function logistic -t  -i %s", model_file_path);
    std::string m_path(vw_model_tem);
    model = VW::initialize(m_path);
    if (NULL == model) {
        //Error 
    }
    pthread_rwlock_unlock(&vw_pmodel_rwlock);
    free(vw_model_tem);
}

我们认为VW::finish(*model)会处理内存释放，还是有其他办法？我们认为内存泄漏在libboost库中，请指导我们如何消除内存泄漏。