[Bug fortran/83319] New: [7/8 Regression] ICE on use of allocatable component in derived type coarray defined in module

["damian at sourceryinstitute dot org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83319

            Bug ID: 83319
           Summary: [7/8 Regression] ICE on use of allocatable component
                    in derived type coarray defined in module
           Product: gcc
           Version: 7.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: damian at sourceryinstitute dot org
  Target Milestone: ---

Presumably the internal compiler error (ICE) demonstrated below is somehow
related to the known regression in support for allocatable components in
derived type coarrays, which is issue 422 on the OpenCoarrays repository.
OpenCoarrays issue 422, however, generates a runtime error message inside the
coarray ABI, whereas this issue generates a compile-time error message so it's
a compiler-side problem.  Also, OpenCoarrays issue 422 involves communication;
whereas this is much more basic: the ICE appears when I do anything with the
allocatable component so this is an even more serious regression on top of the
already very serious regression described in issue 422.  (Besides allocating
the component as shown below, I also tried a source allocation and an
assignment to it.)  The ICE disappears if the derived type definition is moved
into the main program.

This is somewhat similar to PR 78935, but 78935 was fixed 11 months ago and
this seems sufficiently different to warrant a separate PR rather than
reopening 78935.

This ICE occurs with today's 7 branch, with 7.2.0, and with the trunk dated
20170921.  The code compiles cleanly with GCC 6.4.0.

$ cat allocatable-component-of-dt-coarray.f90 

module foo_module
  implicit none
  type foo
    integer, allocatable :: i(:)
  end type
end module

  use foo_module
  implicit none
  type(foo), save :: bar[*]
  allocate(bar%i(1))
end

$ gfortran -fcoarray=lib -c allocatable-component-of-dt-coarray.f90 
allocatable-component-of-dt-coarray.f90:8:0:

   use foo_module

internal compiler error: in gfc_conv_descriptor_token, at
fortran/trans-array.c:305
0x6a9130 gfc_conv_descriptor_token(tree_node*)
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-array.c:303
0x6d6858 gfc_trans_structure_assign(tree_node*, gfc_expr*, bool, bool)
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-expr.c:7567
0x6d0b47 gfc_conv_structure(gfc_se*, gfc_expr*, int)
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-expr.c:7686
0x6df17e gfc_trans_assignment_1
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-expr.c:9984
0x6be5ff generate_coarray_sym_init
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-decl.c:5188
0x68dc72 do_traverse_symtree
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/symbol.c:4009
0x6bdc95 generate_coarray_init
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-decl.c:5238
0x6c9954 gfc_generate_function_code(gfc_namespace*)
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/trans-decl.c:6273
0x65b736 translate_all_program_units
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/parse.c:6074
0x65b736 gfc_parse_file()
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/parse.c:6274
0x69ff5f gfc_be_parse_file
       
/home/rouson/Desktop/Builds/opencoarrays/prerequisites/downloads/gcc-7-branch/gcc/fortran/f95-lang.c:204
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

$ gfortran --version
GNU Fortran (GCC) 7.2.1 20171208