[Bug fortran/113866] New: ice in generic_simplify_COND_EXPR

[Bug fortran/113866] New: ice in generic_simplify_COND_EXPR

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

            Bug ID: 113866
           Summary: ice in generic_simplify_COND_EXPR
           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 57380
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57380&action=edit
F90 source code

For this F90 source code file:

./Lower/HLFIR/bindc-assumed-length.f90

from the flang testsuite at

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

when compiled by recent gfortran, does this:

est $ ~/gcc/results.20240210.asan.ubsan/bin/gfortran -c -w
./Lower/HLFIR/bindc-assumed-length.f90
./Lower/HLFIR/bindc-assumed-length.f90:39:29:

   39 |   call bindc_optional(c1, c3)
      |                             1
internal compiler error: Segmentation fault
0xf57d79 crash_signal(int)
        /home/dcb38/gcc/working/gcc/../../trunk.20210101/gcc/toplev.cc:317
0x17bdf2f generic_simplify_COND_EXPR(unsigned int, tree_code, tree_node*,
tree_node*, tree_node*, tree_node*)
        /home/dcb38/gcc/working/gcc/generic-match-4.cc:0
0xaecbf8 fold_ternary_loc(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*, tree_node*)

Here is a valgrind version of the same gfortran providing some clues:

test $ ~/gcc/results.20240210.valgrind/bin/gfortran -c -w
./Lower/HLFIR/bindc-assumed-length.f90
==3757741== Invalid read of size 2
==3757741==    at 0x17793EF: generic_simplify_COND_EXPR(unsigned int,
tree_code, tree_node*, tree_node*, tree_node*, tree_node*)
(generic-match-4.cc:10061)
==3757741==    by 0xB082BB: fold_ternary_loc(unsigned int, tree_code,
tree_node*, tree_node*, tree_node*, tree_node*) (fold-const.cc:13144)

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2024-02-10
     Ever confirmed|0                           |1
           Priority|P3                          |P4
             Status|UNCONFIRMED                 |NEW
                 CC|                            |kargl at gcc dot gnu.org

--- Comment #1 from kargl at gcc dot gnu.org ---
Reduced testcase. 

module bindcchar

   contains

      subroutine bindc_optional(c1, c3) bind(c)
         character(*), optional ::  c1, c3(100)
         print *, c1(1:3), c3(5)(1:3)
      end subroutine

      subroutine not_bindc_optional(c1, c3)
         character(*), optional :: c1,  c3(100)
         call bindc_optional(c1, c3)
      end subroutine

end module

Note, the OPTIONAL attribute is required to cause the ICE.
Note, -Wall generates a few warnings.  Perhaps, these should
be errors.

% gfcx -c -Wall fr.f90
fr.f90:5:34:

    5 |       subroutine bindc_optional(c1, c3) bind(c)
      |                                  1
Warning: Variable ‘c1’ at (1) is a dummy argument of the BIND(C) procedure
‘bindc_optional’ but may not be C interoperable [-Wc-binding-type]
fr.f90:5:38:

    5 |       subroutine bindc_optional(c1, c3) bind(c)
      |                                      1
Warning: Variable ‘c3’ at (1) is a dummy argument of the BIND(C) procedure
‘bindc_optional’ but may not be C interoperable [-Wc-binding-type]
fr.f90:12:36:

   12 |          call bindc_optional(c1, c3)
      |                                    1

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
                 CC|                            |anlauf at gcc dot gnu.org

--- Comment #2 from anlauf at gcc dot gnu.org ---
Argument passing and the handling of optional arguments differs for bind(c)
procedures from regular ones.  For character, the length is not passed as
a hidden argument but in the CFI descriptor.

Tentative partial fix for comment#1:

diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index 67abca9f6ba..42ef1cd271d 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -7270,7 +7271,8 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym,
         an intrinsic subroutine, however, fsym is NULL, but we might still
         have an optional argument, so we proceed to the substitution
         just in case.  */
-      if (e && (fsym == NULL || fsym->attr.optional))
+      if (e && (fsym == NULL || fsym->attr.optional)
+         && !sym->attr.is_bind_c)
        {
          /* If an optional argument is itself an optional dummy argument,
             check its presence and substitute a null if absent.  This is

Likely incomplete; needs checking using variations of dummy and actual args.

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |anlauf at gcc dot gnu.org

--- Comment #3 from anlauf at gcc dot gnu.org ---
Submitted: https://gcc.gnu.org/pipermail/fortran/2024-February/060220.html

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Harald Anlauf <anlauf@gcc.gnu.org>:

https://gcc.gnu.org/g:f4935df217ad89f884f908f39086b322e80123d0

commit r14-8961-gf4935df217ad89f884f908f39086b322e80123d0
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Tue Feb 13 20:19:10 2024 +0100

    Fortran: fix passing of optional dummies to bind(c) procedures [PR113866]

            PR fortran/113866

    gcc/fortran/ChangeLog:

            * trans-expr.cc (gfc_conv_procedure_call): When passing an optional
            dummy argument to an optional dummy argument of a bind(c) procedure
            and the dummy argument is passed via a CFI descriptor, no special
            presence check and passing of a default NULL pointer is needed.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/bind_c_optional-2.f90: New test.

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED
   Target Milestone|---                         |14.0

--- Comment #5 from anlauf at gcc dot gnu.org ---
Fixed on mainline for gcc-14.

[Bug fortran/113866] ice in generic_simplify_COND_EXPR

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113866

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Harald Anlauf
<anlauf@gcc.gnu.org>:

https://gcc.gnu.org/g:5f9144021615f24d038890dab7db2a0b9e84f6d3

commit r13-8506-g5f9144021615f24d038890dab7db2a0b9e84f6d3
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Tue Feb 13 20:19:10 2024 +0100

    Fortran: fix passing of optional dummies to bind(c) procedures [PR113866]

            PR fortran/113866

    gcc/fortran/ChangeLog:

            * trans-expr.cc (gfc_conv_procedure_call): When passing an optional
            dummy argument to an optional dummy argument of a bind(c) procedure
            and the dummy argument is passed via a CFI descriptor, no special
            presence check and passing of a default NULL pointer is needed.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/bind_c_optional-2.f90: New test.

    (cherry picked from commit f4935df217ad89f884f908f39086b322e80123d0)