Does memory get allocated with Fortran read() with no I/O list?

I am reading an ascii file with Intel Fortran opened as:

open(10, file=trim(file_name), status='old', action='read', iostat=ierr, iomsg=msg)

To skip some file lines which I do not want to store I am using read() with no I/O list:

read(10, *)

VTune reports 53 GB allocated at the read() with no I/O list:

enter image description here

Is that memory really allocated or is it that VTune incorrectly identifies memory allocation? What causes this behaviour?


  • No, there is not 53+GB of virtual memory being allocated at that point. The read with no I/O list likely allocates no memory at all.(I am a former Intel Fortran compiler developer.)