[Bug fortran/52724] New: Internal read with character(kind=4) data

[Bug fortran/52724] New: Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

             Bug #: 52724
           Summary: Internal read with character(kind=4) data
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: tkoenig@gcc.gnu.org


This code in io/unit.c looks fishy:

  /* Set initial values for unit parameters.  */
  if (dtp->common.unit)
    {
      iunit->s = open_internal4 (dtp->internal_unit - start_record,
                 dtp->internal_unit_len, -start_record);
      fbuf_init (iunit, 256);
    }
  else
    iunit->s = open_internal (dtp->internal_unit - start_record,
                  dtp->internal_unit_len, -start_record);

because it supposes that an internal unit for character(kind=4) data
has an internal unit number which is unequal to zero.

And, in fact, this fails:

ig25@linux-fd1f:~/Krempel/Opt> cat foo.f90
!234567
      character buffer4(100)
      integer i

      buffer4 = 4_'123'
      read(buffer4,*) i
      print *,i
      end
ig25@linux-fd1f:~/Krempel/Opt> gfortran foo.f90
ig25@linux-fd1f:~/Krempel/Opt> ./a.out
           1

[Bug fortran/52724] Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jvdelisle at gcc dot
                   |                            |gnu.org

--- Comment #1 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2012-03-26 16:14:36 UTC ---
Hi Jerry,

do you have any idea?

[Bug fortran/52724] Internal read with character(kind=4) data

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

--- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-03-29 01:05:20 UTC ---
I am curious about what this line is doing:

buffer4 = 4_'123'

buffer4 is a kind=1 variable.  have you tried: character(kind=4) buffer4(100) ?

[Bug fortran/52724] Internal read with character(kind=4) data

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-04-02
                 CC|                            |burnus at gcc dot gnu.org
     Ever Confirmed|0                           |1

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-04-02 20:01:08 UTC ---
(In reply to comment #2)
> I am curious about what this line is doing:

      character buffer4(100)
      buffer4 = 4_'123'

Well, that line does what it should do: It assign the value '123' - trimmed to
one character (namely '1') to the array buffer4. The array4 then contains 100
times the value '1'.

(In reply to comment #0)
>       read(buffer4,*) i
>       print *,i
>       end
> ig25@linux-fd1f:~/Krempel/Opt> gfortran foo.f90
> ig25@linux-fd1f:~/Krempel/Opt> ./a.out
>            1

And seemingly that's also what Thomas gets.

 * * *

(In reply to comment #2)
> buffer4 is a kind=1 variable.  have you tried:
> character(kind=4) buffer4(100) ?

Well, with len=1,kind=4 or with len=2,kind=2 one gets, respectively, 1 and 12 -
which is the expected result.

However, the following fails:

      character(len=2,kind=4) buffer4(100)
      integer i
      buffer4 = 4_'123'
      read(buffer4,*) i
      print *,i
      end

Fortran runtime error: Bad integer for item 1 in list input


Printing the value of the array as "print *, buffer4", one gets the expected "
121212...." as output.

And reading the line as
      read(buffer4,'(i5)') i
works and yields "12". Only when replacing the formatted read by a
list-directed read, it fails.

[Bug fortran/52724] Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

--- Comment #4 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2012-04-08 08:55:42 UTC ---
Yes, my original test case was bogus.

Slightly reduced test case:

program main
  implicit none
  integer :: i
  character(len=100,kind=4) :: buffer
  buffer = 4_"123"
  read(buffer,*) i
  print *,i
end program main

[Bug fortran/52724] Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

--- Comment #5 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2012-09-24 18:07:17 UTC ---
This patch looks promising:

Index: list_read.c
===================================================================
--- list_read.c (Revision 191649)
+++ list_read.c (Arbeitskopie)
@@ -199,9 +199,16 @@ next_char (st_parameter_dt *dtp)

   if (is_internal_unit (dtp))
     {
-      char cc;
-      length = sread (dtp->u.p.current_unit->s, &cc, 1);
-      c = cc;
+      /* Check for kind=4 internal unit.  */
+      if (dtp->common.unit)
+       length = sread (dtp->u.p.current_unit->s, &c, sizeof (gfc_char4_t));
+      else
+       {
+         char cc;
+         length = sread (dtp->u.p.current_unit->s, &cc, 1);
+         c = cc;
+       }
+
       if (length < 0)
        {
          generate_error (&dtp->common, LIBERROR_OS, NULL);
Index: unix.c
===================================================================
--- unix.c      (Revision 191649)
+++ unix.c      (Arbeitskopie)
@@ -959,7 +959,7 @@ open_internal4 (char *base, int length, gfc_offset
   s->buffer = base;
   s->buffer_offset = offset;

-  s->active = s->file_length = length;
+  s->active = s->file_length = length * sizeof (gfc_char4_t);

   s->st.vptr = &mem4_vtable;

[Bug fortran/52724] Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

--- Comment #6 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2012-09-29 17:38:50 UTC ---
Author: tkoenig
Date: Sat Sep 29 17:38:46 2012
New Revision: 191854

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191854
Log:
2012-09-29  Thomas König  <tkoenig@gcc.gnu.org>

    PR fortran/52724
    * list_read.c (next_char):  Handle kind=4 characters.
    * unix.c (open_internal4):  Correct lenth of internal file.

2012-09-29  Thomas König  <tkoenig@gcc.gnu.org>

    PR fortran/52724
    * gfortran.dg/internal_readwrite_3.f90:  New test.


Added:
    trunk/gcc/testsuite/gfortran.dg/internal_readwrite_3.f90
Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/libgfortran/ChangeLog
    trunk/libgfortran/io/list_read.c
    trunk/libgfortran/io/unix.c

[Bug fortran/52724] Internal read with character(kind=4) data

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52724

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED

--- Comment #7 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2012-10-28 20:51:37 UTC ---
Fixed on trunk, closing.