https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100954
--- Comment #2 from Taco Jerkface <tacodog311 at gmail dot com> ---
Agreed. A typical user will use unit=42, when manually picking unit numbers.
However the bug remains for automatic, newunit unit numbers.
To reproduce:
1) Open a "newunit" file.
2) close file
3) write to character string
4) "newunit" file appears open, even though it has been closed.
A more concise version of the code would be:
program inquire
implicit none
logical opened
character(len=256) filename
character(len=4) charstring
integer iounit, itmp, ierr
filename='testfile'
! new unit grabs -10
open(newunit=iounit,file=trim(filename) )
write(*,*) 'Opened unit',iounit
! now -10 is open
inquire(iounit, opened=opened,iostat=ierr)
write(*,*) 'Unit',iounit,'open?',opened,ierr
! close it
close(iounit)
write(*,*) 'Closed unit',iounit
! now -10 is closed
inquire(iounit, opened=opened,iostat=ierr)
write(*,*) 'Unit',iounit,'open?',opened,ierr
itmp=0
write(charstring, '(I4.4)') itmp
write(*,*) 'wrote into charstring ', trim(charstring)
! now -10 is reported as open again, but it is not
inquire(iounit, opened=opened,iostat=ierr)
write(*,*) 'Unit',iounit,'open?',opened,ierr
endprogram inquire
