[Bug fortran/35723] New: Can't use run-time array element in character declaration

[Bug fortran/35723] New: Can't use run-time array element in character declaration

[dick dot hendrickson at gmail dot com]

The following program gives an error message for valid use of
an array element in an expression for an automatic character
array.  

The error message is repeated twice.

Changing from a run-time subscript in the parameter array to a
constant fixes the problem.

Dick Hendrickson

      program try_vf0016
! fails on Windows XP
! gcc version 4.4.0 20080312 (experimental) [trunk revision 133139]
! syntax error for valid syntax

      call       vf0016(  1,  2,  3)

      end
      SUBROUTINE VF0016(nf1,nf2,nf3)
      CHARACTER(LEN=9,KIND=1),DIMENSION(3), PARAMETER
     $     ::  TEST_STRINGS =
     $  (/'       HI','ABC      ','  CDEFG  '/)
      CHARACTER :: TEST_ARRAY
     $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))),  ! changing nf1 to 1 fixes it
     $ SUM(LEN_TRIM(ADJUSTL(TEST_STRINGS))),
     $ LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(3)))),
     $ SUM(LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(NF1:NF3:NF2)))))   )

       print *, 2, 10, 5, 7
       print *, shape (test_array)
         end



C:\g_experiments\gfortran>gfortran vf0016.f
vf0016.f:14.24:

     $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))),  ! changing nf1 to 1 fixes
                       1
Error: Variable 'test_strings' cannot appear in the expression at (1)
vf0016.f:14.24:

     $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))),  ! changing nf1 to 1 fixes
                       1
Error: Variable 'test_strings' cannot appear in the expression at (1)


-- 
           Summary: Can't use run-time array element in character
                    declaration
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dick dot hendrickson at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723

[Bug fortran/35723] Can't use run-time array element in character declaration

[burnus at gcc dot gnu dot org]

------- Comment #1 from burnus at gcc dot gnu dot org  2008-03-28 19:40 -------
Confirmed.

A simple patch would be the following:

Index: expr.c
===================================================================
--- expr.c      (Revision 133693)
+++ expr.c      (Arbeitskopie)
@@ -2502,6 +2502,7 @@ check_restricted (gfc_expr *e)
          || sym->attr.use_assoc
          || sym->attr.dummy
          || sym->attr.implied_index
+         || sym->attr.flavor == FL_PARAMETER
          || sym->ns != gfc_current_ns
          || (sym->ns->proc_name != NULL
              && sym->ns->proc_name->attr.flavor == FL_MODULE)

However, this also accepts the following invalid program (note the "i"):

      program try_vf0016
      call    vf0016(  1,  2,  3)
      end
      SUBROUTINE VF0016(nf1,nf2,nf3)
      CHARACTER(LEN=9,KIND=1),DIMENSION(3) , PARAMETER
     $     ::  TEST_STRINGS =
     $  (/'       HI','ABC      ','  CDEFG  '/)
      integer :: i = 2
      CHARACTER :: TEST_ARRAY
     $(LEN_TRIM(ADJUSTL(TEST_STRINGS(i))),  ! changing nf1 to 1 fixes it
     $ SUM(LEN_TRIM(ADJUSTL(TEST_STRINGS))),
     $ LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(3)))),
     $ SUM(LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(NF1:NF3:NF2)))))   )

       print *, 2, 10, 5, 7
       print *, shape (test_array)
         end

We therefore need to loop over expr->ref and check_restricted() these
expressions as well. I think that we can throw in another half a dozen checks
as well. ;-)


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Keywords|                            |rejects-valid
   Last reconfirmed|0000-00-00 00:00:00         |2008-03-28 19:40:15
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723

[Bug fortran/35723] Can't use run-time array element in character declaration

[domob at gcc dot gnu dot org]

-- 

domob at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |domob at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2008-03-28 19:40:15         |2008-09-24 09:59:41
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723

[Bug fortran/35723] Can't use run-time array element in character declaration

[domob at gcc dot gnu dot org]

------- Comment #2 from domob at gcc dot gnu dot org  2008-09-25 10:28 -------
I guess this is illegal, too:

PROGRAM main
  IMPLICIT NONE
  CALL test (5, (/ 1, 2, 3, 4, 5, 6, 7, 8, 9 /) )

CONTAINS

  SUBROUTINE test (n, arr)
    IMPLICIT NONE
    INTEGER :: n, arr(:)

    INTEGER :: i = 5
    INTEGER :: local(arr(n))
    INTEGER :: local2(arr(i)) ! { dg-error "XXX" }
  END SUBROUTINE test

END PROGRAM main

where the definition of local is ok, but local2 is illegal.  This program is
however accepted with gfortran without your patch.  I will implement general
checking of the references for EXPR_VARIABLEs that have one.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723

[Bug fortran/35723] Can't use run-time array element in character declaration

[domob at gcc dot gnu dot org]

------- Comment #3 from domob at gcc dot gnu dot org  2008-10-09 07:29 -------
Subject: Bug 35723

Author: domob
Date: Thu Oct  9 07:28:22 2008
New Revision: 141001

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=141001
Log:
2008-10-09  Daniel Kraft  <d@domob.eu>

        PR fortran/35723
        * gfortran.h (gfc_suppress_error): Removed from header.
        (gfc_push_suppress_errors), (gfc_pop_suppress_errors): New methods.
        * array.c (gfc_array_size): Use new gfc_push/pop_suppress_errors
        instead of directly changing gfc_suppress_error.
        * intrinsic.c (gfc_intrinsic_func_interface): Ditto.
        (gfc_intrinsic_sub_interface): Ditto.
        * error.c (suppress_errors): Made static from `gfc_suppress_error'.
        (gfc_push_suppress_errors), (gfc_pop_suppress_errors): New methods.
        (gfc_notify_std), (gfc_error): Use new static name of global.
        * expr.c (check_arglist), (check_references): New methods.
        (check_restricted): Check arglists and references of EXPR_FUNCTIONs
        and EXPR_VARAIBALEs, respectively.  Allow PARAMETER symbols.

2008-10-09  Daniel Kraft  <d@domob.eu>

        PR fortran/35723
        * gfortran.dg/restricted_expression_1.f90: New test.
        * gfortran.dg/restricted_expression_2.f90: New test.
        * gfortran.dg/restricted_expression_3.f90: New test.

Added:
    trunk/gcc/testsuite/gfortran.dg/restricted_expression_1.f90
    trunk/gcc/testsuite/gfortran.dg/restricted_expression_2.f90
    trunk/gcc/testsuite/gfortran.dg/restricted_expression_3.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/array.c
    trunk/gcc/fortran/error.c
    trunk/gcc/fortran/expr.c
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/intrinsic.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723

[Bug fortran/35723] Can't use run-time array element in character declaration

[domob at gcc dot gnu dot org]

------- Comment #4 from domob at gcc dot gnu dot org  2008-10-09 07:33 -------
Fixed.


-- 

domob at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35723