[Bug fortran/99257] New: ICE in build_field, at fortran/trans-common.c:303

[Bug fortran/99257] New: ICE in build_field, at fortran/trans-common.c:303

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99257

            Bug ID: 99257
           Summary: ICE in build_field, at fortran/trans-common.c:303
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

Presumably valid code, affects versions down to at least r5.
In module m2 variable a is visible, b and c are not.


$ cat z1.f90
module m
   integer :: a = 1
   integer :: b = 2
   integer :: c
   equivalence (b, c)
end
module m2
   use m, only : a
contains
   subroutine b
   end
end


$ cat z2.f90
module m
   private
   integer, public :: a = 1
   integer :: b = 2
   integer :: c
   equivalence (b, c)
end
module m2
   use m
contains
   subroutine b
   end
end


$ gfortran-11-20210221 -c z1.f90
f951: internal compiler error: Segmentation fault
0xda031f crash_signal
        ../../gcc/toplev.c:327
0xa1b95b contains_struct_check(tree_node*, tree_node_structure_enum, char
const*, int, char const*)
        ../../gcc/tree.h:3462
0xa1b95b size_binop_loc(unsigned int, tree_code, tree_node*, tree_node*)
        ../../gcc/fold-const.c:1900
0x793cea build_field
        ../../gcc/fortran/trans-common.c:303
0x793cea create_common
        ../../gcc/fortran/trans-common.c:669
0x796387 finish_equivalences
        ../../gcc/fortran/trans-common.c:1349
0x796387 gfc_trans_common(gfc_namespace*)
        ../../gcc/fortran/trans-common.c:1386
0x7a92d7 gfc_generate_module_vars(gfc_namespace*)
        ../../gcc/fortran/trans-decl.c:5835
0x776bf1 gfc_generate_module_code(gfc_namespace*)
        ../../gcc/fortran/trans.c:2296
0x720821 translate_all_program_units
        ../../gcc/fortran/parse.c:6338
0x720821 gfc_parse_file()
        ../../gcc/fortran/parse.c:6620
0x76dbcf gfc_be_parse_file
        ../../gcc/fortran/f95-lang.c:212

[Bug fortran/99257] ICE in build_field, at fortran/trans-common.c:303

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99257

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2021-02-25
     Ever confirmed|0                           |1

--- Comment #1 from anlauf at gcc dot gnu.org ---
Confirmed.

The module file m.mod looks funny.  It looks especially wrong for z2.f90