Re: [OMPI users] Incorrect function call in simple C program

[Thomas Jahns]

On May 10, 2016, at 12:26 , Gilles Gouaillardet wrote:
except if you #include the libc header in your app, *and* your send  
function has a different prototype, I do not see how clang can issue  
a warning

(except of course if clang "knows" all the libc subroutines ...)


not sure if that helps the OP, but for those who have it available:  
IBM xlc "knows" all the libc names and will warn (assuming the  
corresponding flags are set) even when not including the header in  
question. Expect to get warnings for things like parameters named  
index though.


Regards, Thomas



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Re: [OMPI users] Incorrect function call in simple C program

[Gilles Gouaillardet]

except if you #include the libc header in your app, *and* your send
function has a different prototype, I do not see how clang can issue a
warning
(except of course if clang "knows" all the libc subroutines ...)

Cheers,

Gilles

On Tuesday, May 10, 2016, Devon Hollowood  wrote:

> That worked perfectly. Thank you. I'm surprised that clang didn't emit a
> warning about this!
>
> -Devon
>
> On Mon, May 9, 2016 at 3:42 PM, Gilles Gouaillardet <
> gilles.gouaillar...@gmail.com
> > wrote:
>
>> Devon,
>>
>> send() is a libc function that is used internally by Open MPI, and it
>> uses your user function instead of the libc ne.
>> simply rename your function mysend() or something else that is not used
>> by libc, and your issue will likely be fixed
>>
>> Cheers,
>>
>> Gilles
>>
>>
>> On Tuesday, May 10, 2016, Devon Hollowood > > wrote:
>>
>>> Hello,
>>>
>>> I am having trouble understanding why I am getting an error when running
>>> the program produced by the attached C file. In this file, there are three
>>> short functions: send(), bounce() and main(). send() and bounce() both use
>>> MPI_Send() and MPI_Recv(), but critically, neither one is called from
>>> main(), so as I understand it, neither function should ever be run. main()
>>> is just:
>>>
>>> int main(int argc, char *argv[]) {
 int rank;

 MPI_Init(, );
 MPI_Comm_rank(MPI_COMM_WORLD, );

 MPI_Finalize();
 }

>>>
>>> Despite the fact that the program should never enter send() or bounce(),
>>> when I compile with
>>>
>>> mpicc mpi-issue.c -o mpi-issue

>>>
>>> and run with
>>>
>>> mpirun -n 2 --verbose ./mpi-issue

>>>
>>> I get the following:
>>>
>>> *** An error occurred in MPI_Send
 *** on a NULL communicator
 *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort,
 ***and potentially your MPI job)
 [dhcp-visitor-enr-117-111.slac.stanford.edu:99119] Local abort before
 MPI_INIT completed successfully; not able to aggregate error messages, and
 not able to guarantee that all other processes were killed!
 ---
 Primary job  terminated normally, but 1 process returned
 a non-zero exit code.. Per user-direction, the job has been aborted.
 ---

 --
 mpirun detected that one or more processes exited with non-zero status,
 thus causing
 the job to be terminated. The first process to do so was:

   Process name: [[2829,1],0]
   Exit code:1

 --


>>>
>>> How is it possible to be getting an error in MPI_Send(), if MPI_Send()
>>> never gets run?
>>>
>>> I am running open-mpi 1.10.2, installed via the Homebrew open-mpi
>>> package, and this is running on my Macbook, which is running OSX Yosemite.
>>> I have attached the results of ompi_info --all as ompi_info.txt.bz2
>>>
>>> Any help would be appreciated! Sorry if this is a newb question and I am
>>> missing something obvious--I tried my best to search for this issue but I
>>> couldn't find anything.
>>>
>>> -Devon
>>>
>>
>> ___
>> users mailing list
>> us...@open-mpi.org 
>> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/users
>> Link to this post:
>> http://www.open-mpi.org/community/lists/users/2016/05/29147.php
>>
>
>

Re: [OMPI users] Incorrect function call in simple C program

[Devon Hollowood]

That worked perfectly. Thank you. I'm surprised that clang didn't emit a
warning about this!

-Devon

On Mon, May 9, 2016 at 3:42 PM, Gilles Gouaillardet <
gilles.gouaillar...@gmail.com> wrote:

> Devon,
>
> send() is a libc function that is used internally by Open MPI, and it uses
> your user function instead of the libc ne.
> simply rename your function mysend() or something else that is not used by
> libc, and your issue will likely be fixed
>
> Cheers,
>
> Gilles
>
>
> On Tuesday, May 10, 2016, Devon Hollowood 
> wrote:
>
>> Hello,
>>
>> I am having trouble understanding why I am getting an error when running
>> the program produced by the attached C file. In this file, there are three
>> short functions: send(), bounce() and main(). send() and bounce() both use
>> MPI_Send() and MPI_Recv(), but critically, neither one is called from
>> main(), so as I understand it, neither function should ever be run. main()
>> is just:
>>
>> int main(int argc, char *argv[]) {
>>> int rank;
>>>
>>> MPI_Init(, );
>>> MPI_Comm_rank(MPI_COMM_WORLD, );
>>>
>>> MPI_Finalize();
>>> }
>>>
>>
>> Despite the fact that the program should never enter send() or bounce(),
>> when I compile with
>>
>> mpicc mpi-issue.c -o mpi-issue
>>>
>>
>> and run with
>>
>> mpirun -n 2 --verbose ./mpi-issue
>>>
>>
>> I get the following:
>>
>> *** An error occurred in MPI_Send
>>> *** on a NULL communicator
>>> *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort,
>>> ***and potentially your MPI job)
>>> [dhcp-visitor-enr-117-111.slac.stanford.edu:99119] Local abort before
>>> MPI_INIT completed successfully; not able to aggregate error messages, and
>>> not able to guarantee that all other processes were killed!
>>> ---
>>> Primary job  terminated normally, but 1 process returned
>>> a non-zero exit code.. Per user-direction, the job has been aborted.
>>> ---
>>>
>>> --
>>> mpirun detected that one or more processes exited with non-zero status,
>>> thus causing
>>> the job to be terminated. The first process to do so was:
>>>
>>>   Process name: [[2829,1],0]
>>>   Exit code:1
>>>
>>> --
>>>
>>>
>>
>> How is it possible to be getting an error in MPI_Send(), if MPI_Send()
>> never gets run?
>>
>> I am running open-mpi 1.10.2, installed via the Homebrew open-mpi
>> package, and this is running on my Macbook, which is running OSX Yosemite.
>> I have attached the results of ompi_info --all as ompi_info.txt.bz2
>>
>> Any help would be appreciated! Sorry if this is a newb question and I am
>> missing something obvious--I tried my best to search for this issue but I
>> couldn't find anything.
>>
>> -Devon
>>
>
> ___
> users mailing list
> us...@open-mpi.org
> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/users
> Link to this post:
> http://www.open-mpi.org/community/lists/users/2016/05/29147.php
>

Re: [OMPI users] Incorrect function call in simple C program

[Gilles Gouaillardet]

Devon,

send() is a libc function that is used internally by Open MPI, and it uses
your user function instead of the libc ne.
simply rename your function mysend() or something else that is not used by
libc, and your issue will likely be fixed

Cheers,

Gilles

On Tuesday, May 10, 2016, Devon Hollowood  wrote:

> Hello,
>
> I am having trouble understanding why I am getting an error when running
> the program produced by the attached C file. In this file, there are three
> short functions: send(), bounce() and main(). send() and bounce() both use
> MPI_Send() and MPI_Recv(), but critically, neither one is called from
> main(), so as I understand it, neither function should ever be run. main()
> is just:
>
> int main(int argc, char *argv[]) {
>> int rank;
>>
>> MPI_Init(, );
>> MPI_Comm_rank(MPI_COMM_WORLD, );
>>
>> MPI_Finalize();
>> }
>>
>
> Despite the fact that the program should never enter send() or bounce(),
> when I compile with
>
> mpicc mpi-issue.c -o mpi-issue
>>
>
> and run with
>
> mpirun -n 2 --verbose ./mpi-issue
>>
>
> I get the following:
>
> *** An error occurred in MPI_Send
>> *** on a NULL communicator
>> *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort,
>> ***and potentially your MPI job)
>> [dhcp-visitor-enr-117-111.slac.stanford.edu:99119] Local abort before
>> MPI_INIT completed successfully; not able to aggregate error messages, and
>> not able to guarantee that all other processes were killed!
>> ---
>> Primary job  terminated normally, but 1 process returned
>> a non-zero exit code.. Per user-direction, the job has been aborted.
>> ---
>> --
>> mpirun detected that one or more processes exited with non-zero status,
>> thus causing
>> the job to be terminated. The first process to do so was:
>>
>>   Process name: [[2829,1],0]
>>   Exit code:1
>> --
>>
>>
>
> How is it possible to be getting an error in MPI_Send(), if MPI_Send()
> never gets run?
>
> I am running open-mpi 1.10.2, installed via the Homebrew open-mpi package,
> and this is running on my Macbook, which is running OSX Yosemite. I have
> attached the results of ompi_info --all as ompi_info.txt.bz2
>
> Any help would be appreciated! Sorry if this is a newb question and I am
> missing something obvious--I tried my best to search for this issue but I
> couldn't find anything.
>
> -Devon
>

[OMPI users] Incorrect function call in simple C program

[Devon Hollowood]

Hello,

I am having trouble understanding why I am getting an error when running
the program produced by the attached C file. In this file, there are three
short functions: send(), bounce() and main(). send() and bounce() both use
MPI_Send() and MPI_Recv(), but critically, neither one is called from
main(), so as I understand it, neither function should ever be run. main()
is just:

int main(int argc, char *argv[]) {
> int rank;
>
> MPI_Init(, );
> MPI_Comm_rank(MPI_COMM_WORLD, );
>
> MPI_Finalize();
> }
>

Despite the fact that the program should never enter send() or bounce(),
when I compile with

mpicc mpi-issue.c -o mpi-issue
>

and run with

mpirun -n 2 --verbose ./mpi-issue
>

I get the following:

*** An error occurred in MPI_Send
> *** on a NULL communicator
> *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort,
> ***and potentially your MPI job)
> [dhcp-visitor-enr-117-111.slac.stanford.edu:99119] Local abort before
> MPI_INIT completed successfully; not able to aggregate error messages, and
> not able to guarantee that all other processes were killed!
> ---
> Primary job  terminated normally, but 1 process returned
> a non-zero exit code.. Per user-direction, the job has been aborted.
> ---
> --
> mpirun detected that one or more processes exited with non-zero status,
> thus causing
> the job to be terminated. The first process to do so was:
>
>   Process name: [[2829,1],0]
>   Exit code:1
> --
>
>

How is it possible to be getting an error in MPI_Send(), if MPI_Send()
never gets run?

I am running open-mpi 1.10.2, installed via the Homebrew open-mpi package,
and this is running on my Macbook, which is running OSX Yosemite. I have
attached the results of ompi_info --all as ompi_info.txt.bz2

Any help would be appreciated! Sorry if this is a newb question and I am
missing something obvious--I tried my best to search for this issue but I
couldn't find anything.

-Devon
#include "mpi.h"
#include 
#include 


void send(int msg_len, int partner) {
// initialize buffer
unsigned char *buffer =
(unsigned char *)malloc(msg_len * sizeof(unsigned char));
for(int i = 0; i < msg_len; ++i) {
buffer[i] = i % 256;
}

// time bounce
double start_t = MPI_Wtime();
MPI_Send(buffer, msg_len, MPI_UNSIGNED_CHAR, partner, msg_len,
MPI_COMM_WORLD);
MPI_Recv(buffer, msg_len, MPI_UNSIGNED_CHAR, partner, msg_len,
MPI_COMM_WORLD, MPI_STATUS_IGNORE);
double end_t = MPI_Wtime();

free(buffer);
double time_taken = end_t - start_t;
printf("%d: %e\n", msg_len, time_taken);
}

void bounce(int msg_len, int partner) {
unsigned char *buffer = (unsigned char *) malloc(msg_len);
MPI_Recv(buffer, msg_len, MPI_UNSIGNED_CHAR, partner, msg_len,
MPI_COMM_WORLD, MPI_STATUS_IGNORE);
MPI_Send(buffer, msg_len, MPI_UNSIGNED_CHAR, partner, msg_len,
MPI_COMM_WORLD);
free(buffer);
}


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

MPI_Init(, );
MPI_Comm_rank(MPI_COMM_WORLD, );

MPI_Finalize();
}


ompi_info.txt.bz2
Description: BZip2 compressed data