Question

在我为MPI编写C ++包装器的过程中，我遇到MPI_Test()中的分段错误，其原因是我无法弄清楚。

以下代码是一个最小的崩溃示例，可以使用mpic++ -std=c++11 -g -o test test.cpp && ./test编译和运行：

#include <stdlib.h>
#include <stdio.h>
#include <memory>
#include <mpi.h>

class Environment {
public:
    static Environment &getInstance() {
        static Environment instance;
        return instance;
    }

    static bool initialized() {
        int ini;
        MPI_Initialized(&ini);
        return ini != 0;
    }

    static bool finalized() {
        int fin;
        MPI_Finalized(&fin);
        return fin != 0;
    }

private:
    Environment() {
        if(!initialized()) {
            MPI_Init(NULL, NULL);
            _initialized = true;
        }
    }

    ~Environment() {
        if(!_initialized)
            return;
        if(finalized())
            return;
        MPI_Finalize();
    }

    bool _initialized{false};

public:
    Environment(Environment const &) = delete;
    void operator=(Environment const &)  = delete;
};

class Status {
private:
    std::shared_ptr<MPI_Status> _mpi_status;
    MPI_Datatype _mpi_type;
};

class Request { 
private:
    std::shared_ptr<MPI_Request> _request;
    int _flag;
    Status _status;
};

int main() {
    auto &m = Environment::getInstance();

    MPI_Request r;
    MPI_Status s;
    int a;
    MPI_Test(&r, &a, &s);

    Request r2;
    printf("b\n");
}

基本上，Environment类是围绕MPI_Init和MPI_Finalize的单例包装器。当程序退出时，MPI将被最终确定，并且第一次实例化类时，将调用MPI_Init。然后我在main()函数中做一些MPI，包含一些其他简单的包装器对象。

上面的代码崩溃了（在我的机器上，OpenMPI和Linux）。但是，它适用于我

评论Request或Status的任何私人成员（甚至int _flag;）
评论最后一行printf("b\n");
将auto &m = Environment::getInstance();替换为MPI_Init()。

这些点之间似乎没有联系，我也不知道在哪里寻找分段错误。

堆栈跟踪是：

[pc13090:05978] *** Process received signal ***
[pc13090:05978] Signal: Segmentation fault (11)
[pc13090:05978] Signal code: Address not mapped (1)
[pc13090:05978] Failing at address: 0x61
[pc13090:05978] [ 0] /usr/lib/libpthread.so.0(+0x11dd0)[0x7fa9cf818dd0]
[pc13090:05978] [ 1] /usr/lib/openmpi/libmpi.so.40(ompi_request_default_test+0x16)[0x7fa9d0357326]
[pc13090:05978] [ 2] /usr/lib/openmpi/libmpi.so.40(MPI_Test+0x31)[0x7fa9d03970b1]
[pc13090:05978] [ 3] ./test(+0xb7ae)[0x55713d1aa7ae]
[pc13090:05978] [ 4] /usr/lib/libc.so.6(__libc_start_main+0xea)[0x7fa9cf470f4a]
[pc13090:05978] [ 5] ./test(+0xb5ea)[0x55713d1aa5ea]
[pc13090:05978] *** End of error message ***
-------------------------------------------------------
Primary job  terminated normally, but 1 process returned
a non-zero exit code. Per user-direction, the job has been aborted.
-------------------------------------------------------
--------------------------------------------------------------------------
mpirun noticed that process rank 0 with PID 0 on node pc13090 exited on signal 11 (Segmentation fault).
--------------------------------------------------------------------------

使用单例/包装类时MPI_Test（）中的分段错误

0 个答案: