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
