我有这个ProcessStasts.h文件,它包含在另外两个.h文件中.

#pragma once

#include <mpi.h>
#include <cstddef>

struct ProcessStats
{
    int rank,
    itLeft,
    crtIt,
    processFlag;
    float speed;
};

MPI_Datatype MPI_Cust_ProcessStats_create()
{
    // set data to create new MPI data type
    MPI_Datatype MPI_Cust_ProcessStats;
    MPI_Datatype dataTypes[5] = {MPI_INT, MPI_INT, MPI_INT, MPI_INT, MPI_FLOAT};
    int blockLengths[5] = {1, 1, 1, 1, 1};
    MPI_Aint offsets[5];

    offsets[0] = (MPI_Aint) offsetof(ProcessStats, rank);
    offsets[1] = (MPI_Aint) offsetof(ProcessStats, itLeft);
    offsets[2] = (MPI_Aint) offsetof(ProcessStats, crtIt);
    offsets[3] = (MPI_Aint) offsetof(ProcessStats, processFlag);
    offsets[4] = (MPI_Aint) offsetof(ProcessStats, speed);

    // create new MPI type based on data from above
    MPI_Type_create_struct(5, blockLengths, offsets, dataTypes, &MPI_Cust_ProcessStats);
    MPI_Type_commit(&MPI_Cust_ProcessStats);

    return MPI_Cust_ProcessStats;
}

当我尝试编译时,我收到此错误：错误LNK2005：已定义MPI_Cust_ProcessStats_create(void).如果我对#include“ProcessStasts.h”指令和使用ProcessStats结构的行进行注释,则从其中一个文件中正确编译.我甚至试图评论依赖于ProcessStats的所有行,只留下#include“ProcessStasts.h”语句,我得到这个lnk错误.怎么了？

解决方法:

你可以像这样写：
首先是ProcessStasts.h

#pragma once

#include <mpi.h>
#include <cstddef>

struct ProcessStats
{
    int rank,
    itLeft,
    crtIt,
    processFlag;
    float speed;
};

MPI_Datatype MPI_Cust_ProcessStats_create();

然后是ProcessStasts.c

#include "ProcessStats.h"
MPI_Datatype MPI_Cust_ProcessStats_create()
{
    // set data to create new MPI data type
    MPI_Datatype MPI_Cust_ProcessStats;
    MPI_Datatype dataTypes[6] = {MPI_INT, MPI_INT, MPI_INT, MPI_INT, MPI_FLOAT};
    int blockLengths[5] = {1, 1, 1, 1, 1};
    MPI_Aint offsets[5];

    offsets[0] = (MPI_Aint) offsetof(ProcessStats, rank);
    offsets[1] = (MPI_Aint) offsetof(ProcessStats, itLeft);
    offsets[2] = (MPI_Aint) offsetof(ProcessStats, crtIt);
    offsets[3] = (MPI_Aint) offsetof(ProcessStats, processFlag);
    offsets[4] = (MPI_Aint) offsetof(ProcessStats, speed);

    // create new MPI type based on data from above
    MPI_Type_create_struct(3, blockLengths, offsets, dataTypes, &MPI_Cust_ProcessStats);
    MPI_Type_commit(&MPI_Cust_ProcessStats);

    return MPI_Cust_ProcessStats;
}

然后,您可以根据需要多次包含ProcessStasts.h.作为建议,不要在头文件中定义函数.