[Bug fortran/57456] New: [OOP] CLASS ALLOCATE with typespec: Too little memory allocated

[Bug fortran/57456] New: [OOP] CLASS ALLOCATE with typespec: Too little memory allocated

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

            Bug ID: 57456
           Summary: [OOP] CLASS ALLOCATE with typespec: Too little memory
                    allocated
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org

The following seems to ignore the typespec ("t2::") when calculating how much
memory is required to allocate:


module m
  implicit none
  type t
    integer :: i
   end type t
  type, extends(t) :: t2
    integer :: j
   end type t2
end module m

program test
  use m
  implicit none
  integer :: i
  class(t), save, allocatable :: y(:)

  allocate (t2 :: y(5)) ! Should malloc 2*4*5 = 40 bytes, mallocs only 20
  select type(y)
  type is (t2)
    do i = 1, 5
      y(i)%i = i ! "Invalid write of size 4"
    end do
  end select
  deallocate(y) ! SIGABRT: Process abort signal.
end

[Bug fortran/57456] [OOP] CLASS ALLOCATE with typespec: Too little memory allocated

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Note: It works if one uses a scalar instead of an array.

[Bug fortran/57456] [OOP] CLASS ALLOCATE with typespec: Too little memory allocated

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> ---
There is a similar problem for:

character(len=:), allocatable :: str(:)
allocate (character(len=5) :: str(5))
end

 * * *

To solve this properly, one should put all the logic into gfc_trans_allocate -
and avoid duplicating it in gfc_array_init_size (which is called from
gfc_array_allocate, which is called from the mentioned gfc_trans_allocate).

Note: Also the evaluation of the type-spec length should be done only once for
  allocate (character(len = f()) :: str(5), str2, str3, str4(10))

[Bug fortran/57456] [OOP] CLASS + CHARACTER ALLOCATE with typespec: For arrays, the typespec is ignored

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

Dominique d'Humieres <dominiq at lps dot ens.fr> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2013-06-27
     Ever confirmed|0                           |1

--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
Is not this PR supposed to have been fixed (partially) by revision 199528?

Revision 199528

Author:    burnus
Date:    Fri May 31 09:41:53 2013 UTC (3 weeks, 6 days ago)
Changed paths:    6
Log Message:    
2013-05-31  Tobias Burnus  <burnus@net-b.de>

        PR fortran/57456
        * trans-array.c (gfc_array_init_size): Use passed type spec,
        when available.
        (gfc_array_allocate): Pass typespec on.
        * trans-array.h (gfc_array_allocate): Update prototype.
        * trans-stmt.c (gfc_trans_allocate): Pass typespec on.

2013-05-31  Tobias Burnus  <burnus@net-b.de>

        PR fortran/57456
        * gfortran.dg/class_array_17.f90: New.

Note that the problem in comment #2 is still there at revision 200486.

[Bug fortran/57456] [OOP] CLASS + CHARACTER ALLOCATE with typespec: For arrays, the typespec is ignored

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Dominique d'Humieres from comment #3)
> Is not this PR supposed to have been fixed (partially) by revision 199528?

Yes. The patch fixes the derived-type issue - but it doesn't solve the
CHARACTER issue. As written in comment 2, the proper way is use one common code
in gfc_trans_allocate, which calculates the byte size, and use it both for
scalars (directly in gfc_trans_allocate) and for arrays in gfc_array_allocate
-> gfc_array_init_size. (One also should evaluate the LEN= expression only
once.)

[Bug fortran/57456] [OOP] CLASS + CHARACTER ALLOCATE with typespec: For arrays, the typespec is ignored

[vehre at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

vehre at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING

--- Comment #5 from vehre at gcc dot gnu.org ---
Remain issue should be fixed with:

https://gcc.gnu.org/ml/fortran/2015-03/msg00074.html
https://gcc.gnu.org/ml/fortran/2015-03/msg00075.html
https://gcc.gnu.org/ml/fortran/2015-03/msg00085.html

[Bug fortran/57456] [OOP] CLASS + CHARACTER ALLOCATE with typespec: For arrays, the typespec is ignored

[vehre at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

--- Comment #6 from vehre at gcc dot gnu.org ---
Author: vehre
Date: Tue Mar 24 10:28:48 2015
New Revision: 221621

URL: https://gcc.gnu.org/viewcvs?rev=221621&root=gcc&view=rev
Log:
gcc/fortran/ChangeLog

2015-03-24  Andre Vehreschild  <vehre@gmx.de>

    PR fortran/64787
    PR fortran/57456
    PR fortran/63230
    * class.c (gfc_add_component_ref):  Free no longer needed
    ref-chains to prevent memory loss.
    (find_intrinsic_vtab): For deferred length char arrays or
    unlimited polymorphic objects, store the size in bytes of one
    character in the size component of the vtab.
    * gfortran.h: Added gfc_add_len_component () define.
    * trans-array.c (gfc_trans_create_temp_array): Switched to new
    function name for getting a class' vtab's field.
    (build_class_array_ref): Likewise.
    (gfc_array_init_size): Using the size information from allocate
    more consequently now, i.e., the typespec of the entity to
    allocate is no longer needed.  This is to address the last open
    comment in PR fortran/57456.
    (gfc_array_allocate): Likewise.
    (structure_alloc_comps): gfc_copy_class_to_class () needs to
    know whether the class is unlimited polymorphic.
    * trans-array.h: Changed interface of gfc_array_allocate () to
    reflect the no longer needed typespec.
    * trans-expr.c (gfc_find_and_cut_at_last_class_ref): New.
    (gfc_reset_len): New.
    (gfc_get_class_array_ref): Switch to new function name for
    getting a class' vtab's field.
    (gfc_copy_class_to_class):  Added flag to know whether the class
    to copy is unlimited polymorphic.  Adding _len dependent code
    then, which calls ->vptr->copy () with four arguments adding
    the length information ->vptr->copy(from, to, from_len, to_cap).
    (gfc_conv_procedure_call): Switch to new function name for
    getting a class' vtab's field.
    (alloc_scalar_allocatable_for_assignment): Use the string_length
    as computed by gfc_conv_expr and not the statically backend_decl
    which may be incorrect when ref-ing.
    (gfc_trans_assignment_1): Use the string_length variable and
    not the rse.string_length.  The former has been computed more
    generally.
    * trans-intrinsic.c (gfc_conv_intrinsic_sizeof): Switch to new
    function name for getting a class' vtab's field.
    (gfc_conv_intrinsic_storage_size): Likewise.
    (gfc_conv_intrinsic_transfer): Likewise.
    * trans-stmt.c (gfc_trans_allocate): Restructured to evaluate
    source=expr3 only once before the loop over the objects to
    allocate, when the objects are not arrays. Doing correct _len
    initialization and calling of vptr->copy () fixing PR 64787.
    (gfc_trans_deallocate): Reseting _len to 0, preventing future
    errors.
    * trans.c (gfc_build_array_ref): Switch to new function name
    for getting a class' vtab's field.
    (gfc_add_comp_finalizer_call): Likewise.
    * trans.h: Define the prototypes for the gfc_class_vtab_*_get ()
    and gfc_vptr_*_get () functions.
    Added gfc_find_and_cut_at_last_class_ref () and
    gfc_reset_len () routine prototype.  Added flag to
    gfc_copy_class_to_class () prototype to signal an unlimited
    polymorphic entity to copy.

gcc/testsuite/ChangeLog

2015-03-24  Andre Vehreschild  <vehre@gmx.de>

    * gfortran.dg/allocate_alloc_opt_13.f90: Added tests for
    source= and mold= expressions functionality.
    * gfortran.dg/allocate_class_4.f90: New test.
    * gfortran.dg/unlimited_polymorphic_20.f90: Added test whether
    copying an unlimited polymorhpic object containing a char array
    to another unlimited polymorphic object respects the _len
    component.
    * gfortran.dg/unlimited_polymorphic_22.f90: Extended to check
    whether deferred length char array allocate works, unlimited
    polymorphic object allocation from a string works and if
    allocating an array of deferred length strings works.
    * gfortran.dg/unlimited_polymorphic_24.f03: New test.


Added:
    trunk/gcc/testsuite/gfortran.dg/allocate_class_4.f90
    trunk/gcc/testsuite/gfortran.dg/unlimited_polymorphic_24.f03
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/class.c
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/fortran/trans-array.h
    trunk/gcc/fortran/trans-expr.c
    trunk/gcc/fortran/trans-intrinsic.c
    trunk/gcc/fortran/trans-stmt.c
    trunk/gcc/fortran/trans.c
    trunk/gcc/fortran/trans.h
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/allocate_alloc_opt_13.f90
    trunk/gcc/testsuite/gfortran.dg/unlimited_polymorphic_20.f90
    trunk/gcc/testsuite/gfortran.dg/unlimited_polymorphic_22.f90

[Bug fortran/57456] [OOP] CLASS + CHARACTER ALLOCATE with typespec: For arrays, the typespec is ignored

[vehre at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57456

vehre at gcc dot gnu.org changed:

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

--- Comment #7 from vehre at gcc dot gnu.org ---
Fixed with commit r221621.