Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Development mailing list

Subject: Re: [OMPI devel] MPI_File_get_size fails for files > 2 GB in Fortran
From: Edgar Gabriel (gabriel_at_[hidden])
Date: 2010-12-20 14:48:39


well, but the f77 interface defines that to be an integer, unless you
want to change the fortran API, you will have to map it to an MPI_Fint
in my opinion.

Edgar

On 12/20/2010 1:36 PM, George Bosilca wrote:
> Nice catch. The sizes are MPI_Offset in C, and therefore we should not cast them as MPI_Fint. I'll take a look, but I doubt it will be before next year. Meanwhile, patches are always welcomed.
>
> george.
>
> On Dec 20, 2010, at 10:59 , William George wrote:
>
>>
>> In Fortran, calls to MPI_File_get_size return a negative value
>> when the file is larger that 2GB.
>>
>> I am using Open MPI 1.4.3 on an x86_64 system. This happens with OpenMPI
>> compiled with Intel compilers or GCC, so I don't think it has
>> anything to do with the particular compiler in use.
>>
>> I can fix this by removing the cast to MPI_Fint in
>> the function mpi_file_get_size_ in ompi/mpi/f77/file_get_size_f.c.
>>
>> Changing:
>> *size = (MPI_Fint) c_size;
>>
>> To:
>>
>> *size = c_size;
>>
>>
>> But my guess is that this is not a proper fix.
>>
>> There are a few other suspicious casts to MPI_Fint in the f77
>> directory too that probably cause similar problems:
>>
>> $ $ grep \(MPI_Fint\) *.c
>> address_f.c: *address = (MPI_Fint) addr;
>> file_get_position_f.c: *offset = (MPI_Fint) c_offset;
>> file_get_position_shared_f.c: *offset = (MPI_Fint) c_offset;
>> file_get_size_f.c: *size = (MPI_Fint) c_size;
>> file_get_view_f.c: *disp = (MPI_Fint) c_disp;
>> type_extent_f.c: *extent = (MPI_Fint)c_extent;
>>
>>
>> I can also fix this problem by compiling OpenMPI with
>> the flag -i8, but promoting all Fortran INTEGERs to 8-bytes
>> does not seem correct either.
>>
>> So - is this a configuration problem, a compile problem.
>> a source code bug, or what? Is there an MPI_FOffsetint
>> and/or MPI_FAddressint type that should be used
>> in these casts?
>>
>>
>> Regards,
>> --
>> Bill
>>
>> William L. George
>> National Institute of Standards and Technology
>> ITL - Applied and Computational Mathematics Division, Stop 8911
>> 100 Bureau Drive
>> Gaithersburg, MD 20899-8911
>>
>>
>> _______________________________________________
>> devel mailing list
>> devel_at_[hidden]
>> http://www.open-mpi.org/mailman/listinfo.cgi/devel
>
>
> _______________________________________________
> devel mailing list
> devel_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/devel

-- 
Edgar Gabriel
Assistant Professor
Parallel Software Technologies Lab      http://pstl.cs.uh.edu
Department of Computer Science          University of Houston
Philip G. Hoffman Hall, Room 524        Houston, TX-77204, USA
Tel: +1 (713) 743-3857                  Fax: +1 (713) 743-3335