[Bug fortran/104849] New: ICE in find_array_section, at fortran/expr.cc:1616

[Bug fortran/104849] New: ICE in find_array_section, at fortran/expr.cc:1616

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

            Bug ID: 104849
           Summary: ICE in find_array_section, at fortran/expr.cc:1616
           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: ---

Affects versions down to at least r5 :


$ cat z1.f90
program p
   integer, parameter :: a(:) = [1, 2]
   integer :: x(2)
   data x /a(:)/
end


$ cat z2.f90
program p
   character(3), parameter :: a(:) = ['123']
   character(3) :: x(1)
   data x /a(:)/
end


$ cat z3.f90
program p
   character, parameter :: c(:) = ['1', '2', '3']
   type t
      integer :: a
      character :: b(3)
   end type
   type(t) :: x = t(1, c(:))
end


$ gfortran-12-20220306 -c z1.f90
f951: internal compiler error: Segmentation fault
0xccad7f crash_signal
        ../../gcc/toplev.cc:322
0x6f39cc find_array_section
        ../../gcc/fortran/expr.cc:1616
0x6f537a simplify_const_ref
        ../../gcc/fortran/expr.cc:1932
0x6f5eae gfc_simplify_expr(gfc_expr*, int)
        ../../gcc/fortran/expr.cc:2323
0x6f611b simplify_parameter_variable
        ../../gcc/fortran/expr.cc:2152
0x6f5067 gfc_reduce_init_expr(gfc_expr*)
        ../../gcc/fortran/expr.cc:3163
0x6f7fd0 gfc_match_init_expr(gfc_expr**)
        ../../gcc/fortran/expr.cc:3209
0x6d8212 match_data_constant
        ../../gcc/fortran/decl.cc:461
0x6d8353 top_val_list
        ../../gcc/fortran/decl.cc:499
0x6d8662 gfc_match_data()
        ../../gcc/fortran/decl.cc:716
0x748681 match_word
        ../../gcc/fortran/parse.cc:67
0x74d87e decode_statement
        ../../gcc/fortran/parse.cc:471
0x74e5ea next_free
        ../../gcc/fortran/parse.cc:1397
0x74e5ea next_statement
        ../../gcc/fortran/parse.cc:1629
0x74fb7b parse_spec
        ../../gcc/fortran/parse.cc:4168
0x752ccc parse_progunit
        ../../gcc/fortran/parse.cc:6192
0x754391 gfc_parse_file()
        ../../gcc/fortran/parse.cc:6737
0x7a1edf gfc_be_parse_file
        ../../gcc/fortran/f95-lang.cc:216

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-03-09
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
                 CC|                            |anlauf at gcc dot gnu.org

--- Comment #1 from anlauf at gcc dot gnu.org ---
Obvious patch for NULL pointer dereference:

diff --git a/gcc/fortran/expr.cc b/gcc/fortran/expr.cc
index c9c0ba4cc2e..86d61fed302 100644
--- a/gcc/fortran/expr.cc
+++ b/gcc/fortran/expr.cc
@@ -1594,7 +1594,9 @@ find_array_section (gfc_expr *expr, gfc_ref *ref)
        {
          if ((begin && begin->expr_type != EXPR_CONSTANT)
              || (finish && finish->expr_type != EXPR_CONSTANT)
-             || (step && step->expr_type != EXPR_CONSTANT))
+             || (step && step->expr_type != EXPR_CONSTANT)
+             || (!begin && !lower)
+             || (!finish && !upper))
            {
              t = false;
              goto cleanup;

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

--- Comment #2 from CVS 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:22015e77d3e45306077396b9de8a8a28bb67fb20

commit r12-7569-g22015e77d3e45306077396b9de8a8a28bb67fb20
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Wed Mar 9 21:58:26 2022 +0100

    Fortran: improve error recovery on invalid array section

    gcc/fortran/ChangeLog:

            PR fortran/104849
            * expr.cc (find_array_section): Avoid NULL pointer dereference on
            invalid array section.

    gcc/testsuite/ChangeLog:

            PR fortran/104849
            * gfortran.dg/pr104849.f90: New test.

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED
   Target Milestone|---                         |12.0

--- Comment #3 from anlauf at gcc dot gnu.org ---
Fixed for gcc-12.  Closing.

Thanks for the report!

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Harald Anlauf
<anlauf@gcc.gnu.org>:

https://gcc.gnu.org/g:50c73234630d51e7d66986710afd1af23851002b

commit r11-10006-g50c73234630d51e7d66986710afd1af23851002b
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Wed Mar 9 21:58:26 2022 +0100

    Fortran: improve error recovery on invalid array section

    gcc/fortran/ChangeLog:

            PR fortran/104849
            * expr.c (find_array_section): Avoid NULL pointer dereference on
            invalid array section.

    gcc/testsuite/ChangeLog:

            PR fortran/104849
            * gfortran.dg/pr104849.f90: New test.

    (cherry picked from commit 22015e77d3e45306077396b9de8a8a28bb67fb20)

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Harald Anlauf
<anlauf@gcc.gnu.org>:

https://gcc.gnu.org/g:9fed680237d2c4242d3273ab8f64c82231d5eeb7

commit r10-10747-g9fed680237d2c4242d3273ab8f64c82231d5eeb7
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Wed Mar 9 21:58:26 2022 +0100

    Fortran: improve error recovery on invalid array section

    gcc/fortran/ChangeLog:

            PR fortran/104849
            * expr.c (find_array_section): Avoid NULL pointer dereference on
            invalid array section.

    gcc/testsuite/ChangeLog:

            PR fortran/104849
            * gfortran.dg/pr104849.f90: New test.

    (cherry picked from commit 22015e77d3e45306077396b9de8a8a28bb67fb20)

[Bug fortran/104849] ICE in find_array_section, at fortran/expr.cc:1616

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104849

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-9 branch has been updated by Harald Anlauf
<anlauf@gcc.gnu.org>:

https://gcc.gnu.org/g:6b8cd1fb402163e16d2a139f4bee346ff0c8f234

commit r9-10187-g6b8cd1fb402163e16d2a139f4bee346ff0c8f234
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Wed Mar 9 21:58:26 2022 +0100

    Fortran: improve error recovery on invalid array section

    gcc/fortran/ChangeLog:

            PR fortran/104849
            * expr.c (find_array_section): Avoid NULL pointer dereference on
            invalid array section.

    gcc/testsuite/ChangeLog:

            PR fortran/104849
            * gfortran.dg/pr104849.f90: New test.

    (cherry picked from commit 22015e77d3e45306077396b9de8a8a28bb67fb20)