[Bug fortran/104555] New: ICE in gfc_compare_derived_types, at fortran/interface.cc:628

[Bug fortran/104555] New: ICE in gfc_compare_derived_types, at fortran/interface.cc:628

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

            Bug ID: 104555
           Summary: ICE in gfc_compare_derived_types, at
                    fortran/interface.cc:628
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

Starts with r10, changed between 20190825 and 20190901 :


$ cat z1.f90
program p
   type t
      character(:), allocatable :: a
   end type
contains
   subroutine s(x)
      class(t) :: x(..)
      select rank (x)
      rank (1)
         select type (y => x)
         type is (t)
         end select
      end select
   end
end


$ gfortran-12-20220213 -c z1.f90
f951: internal compiler error: Segmentation fault
0xcc8a9f crash_signal
        ../../gcc/toplev.cc:322
0x6fbdbc gfc_compare_derived_types(gfc_symbol*, gfc_symbol*)
        ../../gcc/fortran/interface.cc:628
0x792efe gfc_type_is_extension_of(gfc_symbol*, gfc_symbol*)
        ../../gcc/fortran/symbol.cc:5116
0x77373c resolve_select_type
        ../../gcc/fortran/resolve.cc:9451
0x768b23 gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.cc:12173
0x76ab87 resolve_codes
        ../../gcc/fortran/resolve.cc:17536
0x76ac4e gfc_resolve(gfc_namespace*)
        ../../gcc/fortran/resolve.cc:17571
0x768c99 gfc_resolve(gfc_namespace*)
        ../../gcc/fortran/resolve.cc:17556
0x768c99 resolve_block_construct
        ../../gcc/fortran/resolve.cc:10791
0x768c99 gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.cc:12181
0x767eef gfc_resolve_blocks(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.cc:10943
0x769edf resolve_select_rank
        ../../gcc/fortran/resolve.cc:9953
0x769edf gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.cc:12177
0x76ab87 resolve_codes
        ../../gcc/fortran/resolve.cc:17536
0x76aabe resolve_codes
        ../../gcc/fortran/resolve.cc:17519
0x76ac4e gfc_resolve(gfc_namespace*)
        ../../gcc/fortran/resolve.cc:17571
0x752f74 resolve_all_program_units
        ../../gcc/fortran/parse.cc:6586
0x752f74 gfc_parse_file()
        ../../gcc/fortran/parse.cc:6842
0x7a066f gfc_be_parse_file
        ../../gcc/fortran/f95-lang.cc:216

[Bug fortran/104555] ICE in gfc_compare_derived_types, at fortran/interface.cc:628

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

G. Steinmetz <gscfq@t-online.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-invalid-code

--- Comment #1 from G. Steinmetz <gscfq@t-online.de> ---

For comparison :

$ cat z2.f90
program p
   type t
      character(:), allocatable :: a
   end type
contains
   subroutine s(x)
      class(t) :: x(..)
      select rank (x)
      rank (1)
         select type (x)
         type is (t)
         end select
      end select
   end
end

[Bug fortran/104555] ICE in gfc_compare_derived_types, at fortran/interface.cc:628 since r10-2912-g70570ec192745095

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
            Summary|ICE in                      |ICE in
                   |gfc_compare_derived_types,  |gfc_compare_derived_types,
                   |at fortran/interface.cc:628 |at fortran/interface.cc:628
                   |                            |since
                   |                            |r10-2912-g70570ec192745095
   Last reconfirmed|                            |2022-02-24
             Status|UNCONFIRMED                 |NEW
                 CC|                            |marxin at gcc dot gnu.org,
                   |                            |pault at gcc dot gnu.org

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r10-2912-g70570ec192745095.

[Bug fortran/104555] ICE in gfc_compare_derived_types, at fortran/interface.cc:628 since r10-2912-g70570ec192745095

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |anlauf at gcc dot gnu.org

--- Comment #3 from anlauf at gcc dot gnu.org ---
In this case the associate-name is essential in the SELECT TYPE,
as well as the surrounding SELECT RANK, and a CHARACTER component
in the derived type.

Replacing

     character(:), allocatable :: a

by

     character(10) :: a

changes the ICE to a bogus error message with a corrupted variable name.

valgrind gives invalid reads...

[Bug fortran/104555] ICE in gfc_compare_derived_types, at fortran/interface.cc:628 since r10-2912-g70570ec192745095

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

--- Comment #4 from CVS 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:f3e44d079747daf56307ada8a2e2e56b64934014

commit r14-5003-gf3e44d079747daf56307ada8a2e2e56b64934014
Author: Paul Thomas <pault@gcc.gnu.org>
Date:   Mon Oct 30 07:12:40 2023 +0000

    Fortran: Fix a problem with SELECT TYPE selectors [PR104555].

    2023-10-30  Paul Thomas  <pault@gcc.gnu.org>

    gcc/fortran
            PR fortran/104555
            * resolve.cc (resolve_select_type): If the selector expression
            has no class component references and the expression is a
            derived type, copy the typespec of the symbol to that of the
            expression.

    gcc/testsuite/
            PR fortran/104555
            * gfortran.dg/pr104555.f90: New test.

[Bug fortran/104555] ICE in gfc_compare_derived_types, at fortran/interface.cc:628 since r10-2912-g70570ec192745095

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104555

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

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

--- Comment #5 from Paul Thomas <pault at gcc dot gnu.org> ---
It should be noted that the revision in comment 2 introduced select rank.
Before that, the select rank statement gave an "unclassifiable statement" error
and the resulting error cascade.

Fixed on mainline. Closing for now but I am inclined to backport with the patch
for pr104625 in a few weeks time.

Thanks for the report.

Paul