fatal error: mpi.h: No such file or directory #include <mpi.h>

Question

when I compile my script with only

#include <mpi.h>

it tells me that there is no such file or directory. But when i include the path to mpi.h as

#include "/usr/include/mpi/mpi.h"

(the path is correct) it returns:

In file included from /usr/include/mpi/mpi.h:2087:0,
                 from lbm.cc:7:
/usr/include/mpi/openmpi/ompi/mpi/cxx/mpicxx.h:35:17: fatal error: mpi.h: No such file or directory
 #include "mpi.h"
                 ^
compilation terminated.

Anyone know how to fix this?

Solution 1

The problem is almost certainly that you're not using the MPI compiler wrappers. Whenever you're compiling an MPI program, you should use the MPI wrappers:

• C - mpicc
• C++ - mpiCC, mpicxx, mpic++
• FORTRAN - mpifort, mpif77, mpif90

These wrappers do all of the dirty work for you of making sure that all of the appropriate compiler flags, libraries, include directories, library directories, etc. are included when you compile your program.

Solution 2

On my system, I was just missing the Linux package.

sudo apt install libopenmpi-dev
pip install mpi4py

(example of something that uses it that is a good instant test to see if it succeeded)

Succeded.

Solution 3

You can execute:

$ mpicc -showme 

result :

gcc -I/Users/<USER_NAME>/openmpi-2.0.1/include -L/Users/<USER_NAME>/openmpi-2.0.1/lib -lmp

This command shows you the necessary libraries to compile mpicc

Example:

$ mpicc -g  -I/Users/<USER_NAME>/openmpi-2.0.1/include -o [nameExec] [objetcs.o...] [program.c] -lm


$ mpicc -g  -I/Users/<USER_NAME>/openmpi-2.0.1/include -o example file_object.o my_program.c otherlib.o -lm

this command generates executable with your program in example, you can execute :

$ ./example

Solution 4

As suggested above the inclusion of

/usr/lib/openmpi/include 

in the include path takes care of this (in my case)

Solution 5

Debian appears to include the following:

• mpiCC.openmpi
• mpic++.openmpi
• mpicc.openmpi
• mpicxx.openmpi
• mpif77.openmpi
• mpif90.openmpi

I'll test symlinks of each for mpic, etc., and see if that helps the likes of HDF5-openmpi enabled find mpi.h.

Take that back Debian includes symlinks via their alternatives system and it still cannot find the proper paths between HDF5 openmpi packages and mpi.h referenced in the H5public.h header.

View more solutions

Comments

[Marc J. Driftmeyer]

The conundrum lies in the fact that openmpi does not have MPI wrappers for mpicc, mpicxx, etc.

[Wesley Bland]

There may be some implementations that don't provide them, but Open MPI isn't one of them. It definitely has at least mpicc and mpicxx and mpifortan.

[user391339]

can you explain how to fix this? i am trying to make someone's program and it gives the error in the original post. it is looking for mpi.h. I installed api using apt-get. Still get the same error.

[Max]

/usr/lib64/mpi/gcc/openmpi/include/ for OpenSUSE Leap

[Gilles Gouaillardet]

are you suggesting to use the wrappers in order to extract some information and then pass it again to the wrappers ?

[Terry]

No info were given as to how to use those wrappers; adding them to the compiler like -mpiCC, installing a wrapper and including it in source file?

[Hasnaa Ibraheem]

@user391339 and Romario By default your IDE uses cmake or so to compile the .cpp file, right?.. Instead you will use the mpi wrapper (which is simply a compiling/executing command) to compile/execute your program. An example would be: $ mpic++ main.cpp and an example to run your program would be $ mpirun -np 2 a.out

[Jeff Hammond]

Lam in ancient. Don’t use it. Use Open-MPI 3+ or MPICH 3+.