problem reading large fortran unformatted files with ifort 16-17

[Thomas_G_7]

Hello, I recently encountered some issues reading large binary 'unformatted' Fortran files (around 30Gb) with both ifort 16 and 17. With those versions, the reading always stops at approximately 10% of the file with "forrtl: severe (67): input statement requires too much data, unit -129" However with both ifort 15 or gfortran, the file is read flawlessly. I also don't have any issue with Ifort 16 and 17 for smaller files (around 20Gb). I suspect something might have changed in the software environment/default options but I can't find it. Best, Thomas

[Kevin_D_Intel]

We have received similar reports earlier. It is possible you might be experiencing the same underlying issue reported here or here.

If you are using the -assume buffered_io option then try building your application without that to see whether you still experience the same error. If do not see the error without that option, then try upgrading to our latest PSXE 2017 Update 2 which contains a fix for the earlier cited error.

If you are still seeing the error without that option then we would need a small complete reproducer with which to investigate further.

[Thomas_G_7]

I tried compiling with -assume nobuffered_io but it produced the same error. I was actually compiling without any flag.