Stream I/O with advance=no

Hi,

It looks like if you do a read with advance='no' without a variable list on a file opened with access='stream', the advance specified gets applied to the following read as well. Consider this test program:

program advance_test

  implicit none

  integer :: unit = 10
  integer :: i

  open(access='stream', action='write', form='formatted', file='testfile', unit=unit)
  do i = 1, 10
     write(fmt='(i0)', unit=unit) i
  end do
  close(unit=unit)

  open(access='stream', action='read', form='formatted', file='testfile', unit=unit)
  read(fmt='(i1)', advance='no', unit=unit)
  read(fmt=*, unit=unit) i
  write(*, *) i
  read(fmt=*, unit=unit) i
  write(*, *) i
  read(fmt=*, unit=unit) i
  write(*, *) i
  close(unit=unit)

end program advance_test

I would expect the first (advance='no') read to do nothing, the second read to get 1, the third to get 2, and so on. And indeed, using gfortran, this is what I get:

13:13 bjm900@raijin5 noadvance > gfortran file.f90
13:13 bjm900@raijin5 noadvance > ./a.out
           1
           2
           3

Using ifort, however, I get this:

13:12 bjm900@raijin5 noadvance > ifort file.f90
13:13 bjm900@raijin5 noadvance > ./a.out
           1
           1
           2

At a guess, the advance='no' with no variables is inadvertently setting some internal flag that's not being reset before the following read. In the case I'm investigating, this structure is used to reposition the file pointer in a formatted file, i.e.:

read(unit, "(I1)", pos=position, advance="no")

The version of ifort I'm using is

13:23 bjm900@raijin5 noadvance > ifort --version
ifort (IFORT) 15.0.0 20140723
Copyright (C) 1985-2014 Intel Corporation.  All rights reserved.

but it is also like this for at least this earlier version

13:23 bjm900@raijin5 noadvance > ifort --version
ifort (IFORT) 14.0.3 20140422
Copyright (C) 1985-2014 Intel Corporation.  All rights reserved.

Cheers,
Ben