[Bug fortran/113885] New: ice in gimplify_expr, at gimplify.cc:18658

[Bug fortran/113885] New: ice in gimplify_expr, at gimplify.cc:18658

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

            Bug ID: 113885
           Summary: ice in gimplify_expr, at gimplify.cc:18658
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

Created attachment 57392
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57392&action=edit
F90 source code

The attached code, from the flang test suite, does this with recent gcc trunk:

test $ ~/gcc/results/bin/gfortran -c -w
./Lower/HLFIR/elemental-call-with-finalization.f90
./Lower/HLFIR/elemental-call-with-finalization.f90:27:13:

   27 |   x = elem(x)
      |             ^
internal compiler error: in gimplify_expr, at gimplify.cc:18658
xb99d5e gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
        /home/dcb38/gcc/working/gcc/../../trunk.20210101/gcc/gimplify.cc:18658
0xb857bd gimplify_stmt(tree_node**, gimple**)
        /home/dcb38/gcc/working/gcc/../../trunk.20210101/gcc/gimplify.cc:7480
0xb8fdd5 gimplify_modify_expr(tree_node**, gimple**, gimple**, bool)
        /home/dcb38/gcc/working/gcc/../../trunk.20210101/gcc/gimplify.cc:6377
0xb8fdd5 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)


The flang test suite is at:

https://github.com/llvm/llvm-project/tree/main/flang/test

[Bug fortran/113885] [13/14 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Target Milestone|---                         |13.3
                 CC|                            |pault at gcc dot gnu.org
           Priority|P3                          |P4
      Known to work|                            |11.4.1, 12.3.1
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=37336
           Keywords|                            |ice-on-valid-code
   Last reconfirmed|                            |2024-02-12
            Summary|ice in gimplify_expr, at    |[13/14 Regression] ice in
                   |gimplify.cc:18658           |gimplify_expr, at
                   |                            |gimplify.cc:18658 with
                   |                            |finalization
             Status|UNCONFIRMED                 |NEW
      Known to fail|                            |13.2.1, 14.0

--- Comment #1 from anlauf at gcc dot gnu.org ---
Confirmed as a 13/14 regression.

Note that adding a component to type t, e.g., so that we have

  type t
     integer :: i
   contains
     final :: finalize
  end type t

the ICE disappears.

Also note that the patch discussed in pr110987 does *not* help here.

[Bug fortran/113885] [13/14 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pault at gcc dot gnu.org

--- Comment #2 from Paul Thomas <pault at gcc dot gnu.org> ---
Created attachment 57820
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57820&action=edit
Draft fix for this PR

Many thanks for the report.

The attachment needs some cleaning up and testing with other variants that
might generate the problem.

In fact, this is a double regression since the testcase below does not give the
right result for 'x' in the calls to test1 and test2.

The first regression is associated with the derived type having zero components
messing up the finalization calls. Strictly, this is not a regression since the
older versions of gfortran did not attempt the finalization.

The second regression is due to the attempt to place finalization calls in the
correct place relative to the evaluation of the rhs and the assignment to the
lhs. This is the cause of the incorrect results for the testcase below. I
believe that the correct output is:
after test1 x =    2   3
no. final calls =    4
after test2 x =    6   8
no. final calls =   12

nagfor agrees but ifort gives 3 and 8 respectively for the no. of
finalizations.

To my astonishment, given the current stage of the fix, it even regtests OK :-)

Paul

module types
  type t
     integer :: i
   contains
     final :: finalize
  end type t
  integer :: ctr = 0
contains
  impure elemental subroutine finalize(x)
    type(t), intent(inout) :: x
    ctr = ctr + 1
  end subroutine finalize
end module types

impure elemental function elem(x)
  use types
  type(t), intent(in) :: x
  type(t) :: elem
  elem%i = x%i + 1
end function elem

impure elemental function elem2(x, y)
  use types
  type(t), intent(in) :: x, y
  type(t) :: elem2
  elem2%i = x%i + y%i
end function elem2

subroutine test1(x)
  use types
  interface
     impure elemental function elem(x)
       use types
       type(t), intent(in) :: x
       type(t) :: elem
     end function elem
  end interface
  type(t) :: x(:)
  x = elem(x)
end subroutine test1

subroutine test2(x)
  use types
  interface
     impure elemental function elem(x)
       use types
       type(t), intent(in) :: x
       type(t) :: elem
     end function elem
     impure elemental function elem2(x, y)
       use types
       type(t), intent(in) :: x, y
       type(t) :: elem2
     end function elem2
  end interface
  type(t) :: x(:)
  x = elem2(elem(x), elem(x))
end subroutine test2

program test113885
  use types
  interface
    subroutine test1(x)
      use types
      type(t) :: x(:)
    end subroutine
    subroutine test2(x)
      use types
      type(t) :: x(:)
    end subroutine
  end interface
  type(t) :: x(2) = [t(1),t(2)]
  call test1 (x)
  print "(a, 2i4)", "after test1 x = ", x
  print "(a, i4)", "no. final calls = ", ctr
  call test2 (x)
  print "(a, 2i4)", "after test2 x = ", x
  print "(a, i4)", "no. final calls = ",ctr
end

[Bug fortran/113885] [13/14 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Paul Thomas <pault@gcc.gnu.org>:

https://gcc.gnu.org/g:3c793f0361bc66d2a6bf0b3e1fb3234fc511e2a6

commit r14-9719-g3c793f0361bc66d2a6bf0b3e1fb3234fc511e2a6
Author: Paul Thomas <pault@gcc.gnu.org>
Date:   Fri Mar 29 07:23:19 2024 +0000

    Fortran: Fix a gimplifier ICE/wrong result with finalization [PR36337]

    2024-03-29  Paul Thomas  <pault@gcc.gnu.org>

    gcc/fortran
            PR fortran/36337
            PR fortran/110987
            PR fortran/113885
            * trans-expr.cc (gfc_trans_assignment_1): Place finalization
            block before rhs post block for elemental rhs.
            * trans.cc (gfc_finalize_tree_expr): Check directly if a type
            has no components, rather than the zero components attribute.
            Treat elemental zero component expressions in the same way as
            scalars.

    gcc/testsuite/
            PR fortran/113885
            * gfortran.dg/finalize_54.f90: New test.
            * gfortran.dg/finalize_55.f90: New test.

    gcc/testsuite/
            PR fortran/110987
            * gfortran.dg/finalize_56.f90: New test.

[Bug fortran/113885] [13 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[13/14 Regression] ice in   |[13 Regression] ice in
                   |gimplify_expr, at           |gimplify_expr, at
                   |gimplify.cc:18658 with      |gimplify.cc:18658 with
                   |finalization                |finalization

--- Comment #4 from Paul Thomas <pault at gcc dot gnu.org> ---
Updated summary

Paul

[Bug fortran/113885] [13 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Paul Thomas <pault@gcc.gnu.org>:

https://gcc.gnu.org/g:9f204cc695d27d0b8eb69d9a4d266261171185ae

commit r13-8690-g9f204cc695d27d0b8eb69d9a4d266261171185ae
Author: Paul Thomas <pault@gcc.gnu.org>
Date:   Fri Mar 29 07:23:19 2024 +0000

    Fortran: Fix a gimplifier ICE/wrong result with finalization [PR36337]

    2024-03-29  Paul Thomas  <pault@gcc.gnu.org>

    gcc/fortran
            PR fortran/36337
            PR fortran/110987
            PR fortran/113885
            * trans-expr.cc (gfc_trans_assignment_1): Place finalization
            block before rhs post block for elemental rhs.
            * trans.cc (gfc_finalize_tree_expr): Check directly if a type
            has no components, rather than the zero components attribute.
            Treat elemental zero component expressions in the same way as
            scalars.

    gcc/testsuite/
            PR fortran/113885
            * gfortran.dg/finalize_54.f90: New test.
            * gfortran.dg/finalize_55.f90: New test.

    gcc/testsuite/
            PR fortran/110987
            * gfortran.dg/finalize_56.f90: New test.

    (cherry picked from commit 3c793f0361bc66d2a6bf0b3e1fb3234fc511e2a6)

[Bug fortran/113885] [13 Regression] ice in gimplify_expr, at gimplify.cc:18658 with finalization

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113885

Paul Thomas <pault at gcc dot gnu.org> changed:

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

--- Comment #6 from Paul Thomas <pault at gcc dot gnu.org> ---
Fixed on all affected branches. Thanks for the report.

Paul