[Bug libfortran/48960] New: OPEN statement modifies NEWUNIT variable on error

[Bug libfortran/48960] New: OPEN statement modifies NEWUNIT variable on error

[thenlich at users dot sourceforge.net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

           Summary: OPEN statement modifies NEWUNIT variable on error
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libfortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: thenlich@users.sourceforge.net


If the NEWUNIT= specifier in the OPEN statement is used, the variable is
modified if an error occurs during the execution of the OPEN statement.

This does not conform to Fortran 2008 which demands:

9.5.6.12 NEWUNIT= specifier in the OPEN statement

1 The variable is defined with a processor determined NEWUNIT value if no error
occurs during the execution of the OPEN statement. If an error occurs, the
processor shall not change the value of the variable.

Example:

program test_newunit
    integer :: st, un = 0
    open (newunit=un, file='nonexisting.dat', status='old', iostat=st)
    if (un /= 0) call abort
end program test_newunit

Result: If the file 'nonexisting.dat' does not exist, the program aborts.

Expected result: If the file 'nonexisting.dat' does not exist, the program
should not abort.

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

Jerry DeLisle <jvdelisle at gcc dot gnu.org> changed:

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

--- Comment #1 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2011-05-12 18:31:56 UTC ---
Ok, on my list

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

--- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-25 04:24:33 UTC ---
Proposed patch being tested;:

Index: open.c
===================================================================
--- open.c    (revision 194678)
+++ open.c    (working copy)
@@ -844,10 +844,7 @@ st_open (st_parameter_open *opp)
   if ((opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
     {
       if ((opp->common.flags & IOPARM_OPEN_HAS_NEWUNIT))
-    {
-      *opp->newunit = get_unique_unit_number(opp);
-      opp->common.unit = *opp->newunit;
-    }
+    opp->common.unit = get_unique_unit_number(opp);

       u = find_or_create_unit (opp->common.unit);
       if (u->s == NULL)
@@ -859,6 +856,9 @@ st_open (st_parameter_open *opp)
       else
     already_open (opp, u, &flags);
     }
-
+    
+  if ((opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
+    *opp->newunit = opp->common.unit;
+  
   library_end ();
 }

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

--- Comment #3 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-25 04:52:04 UTC ---
A slight modification and still testing.

@@ -859,6 +856,10 @@ st_open (st_parameter_open *opp)
       else
     already_open (opp, u, &flags);
     }
-
+    
+  if ((opp->common.flags & IOPARM_OPEN_HAS_NEWUNIT)
+      && (opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
+    *opp->newunit = opp->common.unit;
+  
   library_end ();
 }

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

--- Comment #4 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-26 18:11:50 UTC ---
Author: jvdelisle
Date: Wed Dec 26 18:11:42 2012
New Revision: 194724

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194724
Log:
2012-12-26  Jerry DeLisle  <jvdelisle@gcc.gnu.org>

    PR libfortran/48960
    * io/open.c (st_parameter_open):  Assign newunit number to user
    variable only if the the associated open statement is successful.

Modified:
    trunk/libgfortran/ChangeLog
    trunk/libgfortran/io/open.c

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

--- Comment #5 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-27 06:37:15 UTC ---
Fixed on trunk. I will commit a test case before closing this.

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

--- Comment #6 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-27 20:13:50 UTC ---
Author: jvdelisle
Date: Thu Dec 27 20:13:35 2012
New Revision: 194738

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194738
Log:
2012-12-27  Jerry DeLisle  <jvdelisle@gcc.gnu.org>

    PR fortran/48960
    * gfortran.dg/newunit_3.f90: New.

Added:
    trunk/gcc/testsuite/gfortran.dg/newunit_3.f90
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug libfortran/48960] OPEN statement modifies NEWUNIT variable on error

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48960

Jerry DeLisle <jvdelisle at gcc dot gnu.org> changed:

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

--- Comment #7 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2012-12-27 20:14:56 UTC ---
Closing