为什么 MPI_Barrier 会导致 C++ 中的分段错误

我已将程序简化为以下示例：

#include <mpi.h>

int main(int argc, char * argv[]) {
    int rank, size;

    MPI_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    MPI_Barrier(MPI_COMM_WORLD);
    MPI_Finalize();
    return 0;
}

我编译并运行代码，得到以下结果：

My-MacBook-Pro-2:xCode_TrapSim user$ mpicxx -g -O0 -Wall barrierTest.cpp -o barrierTestExec
My-MacBook-Pro-2:xCode_TrapSim user$ mpiexec -n 2 ./barrierTestExec

==================================================================================    =
=   BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
=   PID 21633 RUNNING AT My-MacBook-Pro-2.local
=   EXIT CODE: 11
=   CLEANING UP REMAINING PROCESSES
=   YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
===================================================================================
YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Segmentation fault: 11 (signal 11)
This typically refers to a problem with your application.
Please see the FAQ page for debugging suggestions

如果我注释掉 MPI_Barrier，或者仅在一个节点上运行该程序，则代码运行良好。我正在使用以下编译器：

My-MacBook-Pro-2:xCode_TrapSim user$ mpiexec --version
HYDRA build details:
Version:                                 3.2
Release Date:                            Wed Nov 11 22:06:48 CST 2015
CC:                              clang    
CXX:                             clang++    
F77:                             /usr/local/bin/gfortran   
F90:                             /usr/local/bin/gfortran   
Configure options:                       '--disable-option-checking' '--prefix=/usr/local/Cellar/mpich/3.2_1' '--disable-dependency-tracking' '--disable-silent-rules' '--mandir=/usr/local/Cellar/mpich/3.2_1/share/man' 'CC=clang' 'CXX=clang++' 'FC=/usr/local/bin/gfortran' 'F77=/usr/local/bin/gfortran' '--cache-file=/dev/null' '--srcdir=.' 'CFLAGS= -O2' 'LDFLAGS=' 'LIBS=-lpthread ' 'CPPFLAGS= -I/private/tmp/mpich-20160606-48824-1qsaqn8/mpich-3.2/src/mpl/include -I/private/tmp/mpich-20160606-48824-1qsaqn8/mpich-3.2/src/mpl/include -I/private/tmp/mpich-20160606-48824-1qsaqn8/mpich-3.2/src/openpa/src -I/private/tmp/mpich-20160606-48824-1qsaqn8/mpich-3.2/src/openpa/src -D_REENTRANT -I/private/tmp/mpich-20160606-48824-1qsaqn8/mpich-3.2/src/mpi/romio/include'
Process Manager:                         pmi
Launchers available:                     ssh rsh fork slurm ll lsf sge manual persist
Topology libraries available:            hwloc
Resource management kernels available:   user slurm ll lsf sge pbs cobalt
Checkpointing libraries available:       
Demux engines available:                 poll select


My-MacBook-Pro-2:xCode_TrapSim user$ clang --version
Apple LLVM version 7.3.0 (clang-703.0.31)
Target: x86_64-apple-darwin15.5.0
Thread model: posix
InstalledDir:     /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

这看起来应该是一个小问题，但我似乎无法弄清楚。为什么 MPI_Barrier 会导致这个简单的代码出现段错误？

很难确定您的安装出了什么问题。但是，如果您可以使用任何 MPI 风格，也许您可​​以尝试这个：

http://www.owsiak.org/?p=3492 http://www.owsiak.org/?p=3492

我只能说，它可以与 Open MPI 配合使用

~/opt/usr/local/bin/mpicxx -g -O0 -Wall barrierTestExec.cpp -o barrierTestExec
~/opt/usr/local/bin/mpiexec -n 2 ./barrierTestExec

我的情况也不例外。这似乎确实是环境特定的。