[Bug fortran/41235] New: Missing explicit interface for variable-length character functions

[Bug fortran/41235] New: Missing explicit interface for variable-length character functions

[burnus at gcc dot gnu dot org]

From
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/d710371aed91e75f#

The following program is invalid. This is diagnosed at compile time by ifort,

test.f90(19): error #6832: This passed length character name has been used in
an invalid context.   [BIGFUNC]
   character(i) bigfunc
----------------^

and NAG f95

Error: test.f90: CHARACTER*1024 function BIGFUNC referenced with non-constant
length from LEVEL1

and open95

openf95-916 openf95: ERROR LEVEL1, File = test.f90, Line = 19, Column = 17
  "BIGFUNC" has a variable length character result, therefore it must have an
explicit interface.

and g95

   character(i) bigfunc
                1
Error: Nonconstant character function 'bigfunc' at (1) must have an explicit
interface

But not in gfortran - even not with -fwhole-file -fcheck=all.

program main
   implicit none
   character(4) level1
   character(4) answer
   integer i

   do i = 1024, 1, -1023
      write(*,'(a,i0)') 'Invoking level1 with i = ', i
      answer = level1(i)
      write(*,'(a)') 'Back from level1'
      write(*,'(a,i0,2a)') 'i = ', i, ', answer = ', answer
   end do
end program main

function level1(i)
   implicit none
   integer i
   character(4) level1
   character(i) bigfunc

   level1 = bigfunc()
end function level1

function bigfunc()
   implicit none
   character(1024) bigfunc

   bigfunc = repeat('b',len(bigfunc))
end function bigfunc


-- 
           Summary: Missing explicit interface for variable-length character
                    functions
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: accepts-invalid, diagnostic
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41235

[Bug fortran/41235] Missing explicit interface for variable-length character functions

[burnus at gcc dot gnu dot org]

------- Comment #1 from burnus at gcc dot gnu dot org  2009-12-10 21:30 -------
>From the standard (F2003):
"12.3.1.1 Explicit interface"
"A procedure [...] shall have an explicit interface if it is referenced and
[...]
 (3) The procedure has a result that [...]
   (c) has a nonassumed type parameter value that is not an initialization
expression,"

 * * *

Patch: http://gcc.gnu.org/ml/fortran/2009-12/msg00061.html


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-12-10 21:30:28
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41235

[Bug fortran/41235] Missing explicit interface for variable-length character functions

[burnus at gcc dot gnu dot org]

------- Comment #2 from burnus at gcc dot gnu dot org  2009-12-15 08:37 -------
Subject: Bug 41235

Author: burnus
Date: Tue Dec 15 08:37:41 2009
New Revision: 155247

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=155247
Log:
2009-12-15  Tobias Burnus  <burnus@net-b.de>
            Daniel Franke  <franke.daniel@gmail.com>

        PR fortran/41235
        * resolve.c (resolve_global_procedure): Add check for
        presence of an explicit interface for nonconstant,
        nonassumed character-length functions.
        (resolve_fl_procedure): Remove check for nonconstant
        character-length functions.

2009-12-15  Tobias Burnus  <burnus@net-b.de>

        PR fortran/41235
        * auto_char_len_1.f90: New test.
        * auto_char_len_2.f90: New test.
        * auto_char_len_4.f90: Correct test.


Added:
    trunk/gcc/testsuite/gfortran.dg/auto_char_len_1.f90
    trunk/gcc/testsuite/gfortran.dg/auto_char_len_2.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/resolve.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/auto_char_len_4.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41235

[Bug fortran/41235] Missing explicit interface for variable-length character functions

[burnus at gcc dot gnu dot org]

------- Comment #3 from burnus at gcc dot gnu dot org  2009-12-15 08:45 -------
FIXED


-- 

burnus at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41235

[Bug fortran/41235] Missing explicit interface for variable-length character functions

[hjl dot tools at gmail dot com]

-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41235