[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[ivan.tubert-brohman at schrodinger dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

Ivan Tubert-Brohman <ivan.tubert-brohman at schrodinger dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ivan.tubert-brohman@schrodi
                   |                            |nger.com

--- Comment #3 from Ivan Tubert-Brohman <ivan.tubert-brohman at schrodinger dot com> ---
I also encountered this issue. I was trying the example given by Metcalf et al.
on _Modern Fortran Explained_ (2018), section 21.4, "Assumed character length":

      interface
         subroutine err_msg(string) bind(c)
            use iso_c_binding
            character(*, c_char), intent(in):: string
         end subroutine err_msg
      end interface

The example worked with the Intel Fortran compiler, but with gfortran 11.1 I
get

  Error: Character argument ‘string’ at (1) must be length 1 because procedure
‘err_msg’ is BIND(C)

I only comment to confirm that both a famous author and an alternative compiler
implementation agree with the interpretation of the standard that this should
work. :-)

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

sandra at gcc dot gnu.org changed:

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

--- Comment #4 from sandra at gcc dot gnu.org ---
Tobias's recent commit (which he forgot to tag with this issue) changed the
"must be length 1" messages to something more descriptive, but the
functionality itself still isn't working.

commit b3d4011ba10275fbd5d6ec5a16d5aaebbdfb5d3c
Author: Tobias Burnus <tobias@codesourcery.com>
Date:   Wed Jul 21 09:36:48 2021 +0200

    Fortran: Fix bind(C) character length checks

    gcc/fortran/ChangeLog:

        * decl.c (gfc_verify_c_interop_param): Update for F2008 + F2018
        changes; reject unsupported bits with 'Error: Sorry,'.
        * trans-expr.c (gfc_conv_procedure_call): Fix condition to
        For using CFI descriptor with characters.

    gcc/testsuite/ChangeLog:

        * gfortran.dg/iso_c_binding_char_1.f90: Update dg-error.
        * gfortran.dg/pr32599.f03: Use -std=-f2003 + update comment.
        * gfortran.dg/bind_c_char_10.f90: New test.
        * gfortran.dg/bind_c_char_6.f90: New test.
        * gfortran.dg/bind_c_char_7.f90: New test.
        * gfortran.dg/bind_c_char_8.f90: New test.
        * gfortran.dg/bind_c_char_9.f90: New test.

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

--- Comment #5 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Crossref:
See also PR 100906 "Bind(c): failure handling character with len/=1"
and PR 100906 comment 4 regarding a status (what needs to be done).

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-08-31
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #6 from Tobias Burnus <burnus at gcc dot gnu.org> ---
With my bind-C array descriptor patch, all tests except of 
strg_print_2("abc").
(To be submitted; I will include this testcase as
gfortran.dg/bind-c-char-descr.f90
with the failing test commented.)

The still FAILING testcase does *not* use BIND(C) - and only TYPE(*) with
assumed-rank: 
That test passes this string to a gfortran array descriptor for type:
  type(*), target, intent(in) :: this(..)
which is then
  c_f_pointer(c_loc(this), strn)
to a Fortran pointer.

The call has:

    scalar.4 = 97;   // that's  'a' -> expected: "abc".
    desc.3.dtype = {.elem_len=1, .rank=0, .type=1}; // not the elem_len=1;
should be len*kind
    desc.3.data = (void *) &scalar.4;
    desc.3.span = (integer(kind=8)) desc.3.dtype.elem_len;

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tobias Burnus <burnus@gcc.gnu.org>:

https://gcc.gnu.org/g:64f9623765da3306b0ab6a47997dc5d62c2ea261

commit r12-4467-g64f9623765da3306b0ab6a47997dc5d62c2ea261
Author: Tobias Burnus <tobias@codesourcery.com>
Date:   Mon Oct 18 09:51:36 2021 +0200

    Fortran: Fix Bind(C) Array-Descriptor Conversion

    gfortran uses internally a different array descriptor ("gfc") as
    Fortran 2018 alias TS291113 defines for C interoperability via
    ISO_Fortran_binding.h ("CFI").  Hence, when calling a C function
    from Fortran, it has to be converted in the callee - and if a
    BIND(C) procedure is written in Fortran, the CFI argument has
    to be converted to gfc in order work with the rest of the FE
    code and the library calls.

    Before this patch, part was handled in the FE generated code and
    other parts in libgfortran.  With this patch, all code is generated
    and CFI is defined as proper type - visible in the debugger and to
    the middle end - avoiding both alias issues and missed optimization
    issues.

    This patch also fixes issues like: intent(out) deallocation in
    the bind(C) callee, using the CFI descriptor also for allocatable
    and pointer scalars and for len=* character strings.
    For 'select rank', it also optimizes the code + avoid accessing
    uninitialized memory if the dummy argument is allocatable/a pointer.
    It additionally rejects passing a descriptorless type(*) to an
    assumed-rank dummy argument. [F2018:C711]

            PR fortran/102086
            PR fortran/92189
            PR fortran/92621
            PR fortran/101308
            PR fortran/101309
            PR fortran/101635
            PR fortran/92482

    gcc/fortran/ChangeLog:

            * decl.c (gfc_verify_c_interop_param): Remove 'sorry' for
            scalar allocatable/pointer and len=*.
            * expr.c (is_CFI_desc): Return true for for those.
            * gfortran.h (CFI_type_kind_shift, CFI_type_mask,
            CFI_type_from_type_kind, CFI_VERSION, CFI_MAX_RANK,
            CFI_attribute_pointer, CFI_attribute_allocatable,
            CFI_attribute_other, CFI_type_Integer, CFI_type_Logical,
            CFI_type_Real, CFI_type_Complex, CFI_type_Character,
            CFI_type_ucs4_char, CFI_type_struct, CFI_type_cptr,
            CFI_type_cfunptr, CFI_type_other): New #define.
            * trans-array.c (CFI_FIELD_BASE_ADDR, CFI_FIELD_ELEM_LEN,
            CFI_FIELD_VERSION, CFI_FIELD_RANK, CFI_FIELD_ATTRIBUTE,
            CFI_FIELD_TYPE, CFI_FIELD_DIM, CFI_DIM_FIELD_LOWER_BOUND,
            CFI_DIM_FIELD_EXTENT, CFI_DIM_FIELD_SM,
            gfc_get_cfi_descriptor_field, gfc_get_cfi_desc_base_addr,
            gfc_get_cfi_desc_elem_len, gfc_get_cfi_desc_version,
            gfc_get_cfi_desc_rank, gfc_get_cfi_desc_type,
            gfc_get_cfi_desc_attribute, gfc_get_cfi_dim_item,
            gfc_get_cfi_dim_lbound, gfc_get_cfi_dim_extent,
gfc_get_cfi_dim_sm):
            New define/functions to access the CFI array descriptor.
            (gfc_conv_descriptor_type): New function for the GFC descriptor.
            (gfc_get_array_span): Handle expr of CFI descriptors and
            assumed-type descriptors.
            (gfc_trans_array_bounds): Remove 'static'.
            (gfc_conv_expr_descriptor): For assumed type, use the dtype of
            the actual argument.
            (structure_alloc_comps): Remove ' ' inside tabs.
            * trans-array.h (gfc_trans_array_bounds, gfc_conv_descriptor_type,
            gfc_get_cfi_desc_base_addr, gfc_get_cfi_desc_elem_len,
            gfc_get_cfi_desc_version, gfc_get_cfi_desc_rank,
            gfc_get_cfi_desc_type, gfc_get_cfi_desc_attribute,
            gfc_get_cfi_dim_lbound, gfc_get_cfi_dim_extent,
gfc_get_cfi_dim_sm):
            New prototypes.
            * trans-decl.c (gfor_fndecl_cfi_to_gfc, gfor_fndecl_gfc_to_cfi):
            Remove global vars.
            (gfc_build_builtin_function_decls): Remove their initialization.
            (gfc_get_symbol_decl, create_function_arglist,
            gfc_trans_deferred_vars): Update for CFI.
            (convert_CFI_desc): Remove and replace by ...
            (gfc_conv_cfi_to_gfc): ... this function
            (gfc_generate_function_code): Call it; create local GFC var for
CFI.
            * trans-expr.c (gfc_maybe_dereference_var): Handle CFI.
            (gfc_conv_subref_array_arg): Handle the if-noncontigous-only copy
in
            when the result should be a descriptor.
            (gfc_conv_gfc_desc_to_cfi_desc): Completely rewritten.
            (gfc_conv_procedure_call): CFI fixes.
            * trans-openmp.c (gfc_omp_is_optional_argument,
            gfc_omp_check_optional_argument): Handle optional
            CFI.
            * trans-stmt.c (gfc_trans_select_rank_cases): Cleanup, avoid
invalid
            code for allocatable/pointer dummies, which cannot be assumed size.
            * trans-types.c (gfc_cfi_descriptor_base): New global var.
            (gfc_get_dtype_rank_type): Skip rank init for rank < 0.
            (gfc_sym_type): Handle CFI dummies.
            (gfc_get_function_type): Update call.
            (gfc_get_cfi_dim_type, gfc_get_cfi_type): New.
            * trans-types.h (gfc_sym_type): Update prototype.
            (gfc_get_cfi_type): New prototype.
            * trans.c (gfc_trans_runtime_check): Make conditions more
consistent
            to avoid '<logical> AND_THEN <long int>' in conditions.
            * trans.h (gfor_fndecl_cfi_to_gfc, gfor_fndecl_gfc_to_cfi): Remove
            global-var declaration.

    libgfortran/ChangeLog:

            * ISO_Fortran_binding.h (CFI_type_cfunptr): Make unique type again.
            * runtime/ISO_Fortran_binding.c (cfi_desc_to_gfc_desc,
            gfc_desc_to_cfi_desc): Add comment that those are no longer called
            by new code.

    libgomp/ChangeLog:

            * testsuite/libgomp.fortran/optional-bind-c.f90: New test.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/ISO_Fortran_binding_4.f90: Extend testcase.
            * gfortran.dg/PR100914.f90: Remove xfail.
            * gfortran.dg/PR100915.c: Expect CFI_type_cfunptr.
            * gfortran.dg/PR100915.f90: Handle CFI_type_cfunptr !=
CFI_type_cptr.
            * gfortran.dg/PR93963.f90: Extend select-rank tests.
            * gfortran.dg/bind-c-intent-out.f90: Change to dg-do run,
            update scan-dump.
            * gfortran.dg/bind_c_array_params_2.f90: Update/extend scan-dump.
            * gfortran.dg/bind_c_char_10.f90: Update scan-dump.
            * gfortran.dg/bind_c_char_8.f90: Remove dg-error "sorry".
            * gfortran.dg/c-interop/allocatable-dummy.f90: Remove xfail.
            * gfortran.dg/c-interop/c1255-1.f90: Likewise.
            * gfortran.dg/c-interop/c407c-1.f90: Update dg-error.
            * gfortran.dg/c-interop/cf-descriptor-5.f90: Remove xfail.
            * gfortran.dg/c-interop/cf-out-descriptor-3.f90: Likewise.
            * gfortran.dg/c-interop/cf-out-descriptor-4.f90: Likewise.
            * gfortran.dg/c-interop/cf-out-descriptor-5.f90: Likewise.
            * gfortran.dg/c-interop/contiguous-2.f90: Likewise.
            * gfortran.dg/c-interop/contiguous-3.f90: Likewise.
            * gfortran.dg/c-interop/deferred-character-1.f90: Likewise.
            * gfortran.dg/c-interop/deferred-character-2.f90: Likewise.
            * gfortran.dg/c-interop/fc-descriptor-3.f90: Likewise.
            * gfortran.dg/c-interop/fc-descriptor-5.f90: Likewise.
            * gfortran.dg/c-interop/fc-descriptor-6.f90: Likewise.
            * gfortran.dg/c-interop/fc-out-descriptor-3.f90: Likewise.
            * gfortran.dg/c-interop/fc-out-descriptor-4.f90: Likewise.
            * gfortran.dg/c-interop/fc-out-descriptor-5.f90: Likewise.
            * gfortran.dg/c-interop/fc-out-descriptor-6.f90: Likewise.
            * gfortran.dg/c-interop/ff-descriptor-5.f90: Likewise.
            * gfortran.dg/c-interop/ff-descriptor-6.f90: Likewise.
            * gfortran.dg/c-interop/fc-descriptor-7.f90: Remove xfail + extend.
            * gfortran.dg/c-interop/fc-descriptor-7-c.c: Update for changes.
            * gfortran.dg/c-interop/shape.f90: Add implicit none.
            * gfortran.dg/c-interop/typecodes-array-char-c.c: Add kind=4 char.
            * gfortran.dg/c-interop/typecodes-array-char.f90: Likewise.
            * gfortran.dg/c-interop/typecodes-array-float128.f90: Remove xfail.
            * gfortran.dg/c-interop/typecodes-scalar-basic.f90: Likewise.
            * gfortran.dg/c-interop/typecodes-scalar-float128.f90: Likewise.
            * gfortran.dg/c-interop/typecodes-scalar-int128.f90: Likewise.
            * gfortran.dg/c-interop/typecodes-scalar-longdouble.f90: Likewise.
            * gfortran.dg/iso_c_binding_char_1.f90: Remove dg-error "sorry".
            * gfortran.dg/pr93792.f90: Turn XFAIL into PASS.
            * gfortran.dg/ISO_Fortran_binding_19.f90: New test.
            * gfortran.dg/assumed_type_12.f90: New test.
            * gfortran.dg/assumed_type_13.c: New test.
            * gfortran.dg/assumed_type_13.f90: New test.
            * gfortran.dg/bind-c-char-descr.f90: New test.
            * gfortran.dg/bind-c-contiguous-1.c: New test.
            * gfortran.dg/bind-c-contiguous-1.f90: New test.
            * gfortran.dg/bind-c-contiguous-2.f90: New test.
            * gfortran.dg/bind-c-contiguous-3.c: New test.
            * gfortran.dg/bind-c-contiguous-3.f90: New test.
            * gfortran.dg/bind-c-contiguous-4.c: New test.
            * gfortran.dg/bind-c-contiguous-4.f90: New test.
            * gfortran.dg/bind-c-contiguous-5.c: New test.
            * gfortran.dg/bind-c-contiguous-5.f90: New test.

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code

--- Comment #8 from Tobias Burnus <burnus at gcc dot gnu.org> ---
The BIND(C) issue is fixed - but I keep this PR open as there is still an issue
with the non-bind(C) part. Namely:

   testsuite/gfortran.dg/bind-c-char-descr.f90

fails for:

...
  subroutine strg_print_2(this, xfail)
    if(associated(strn))then
      if (len (strn) /= 3) stop 31
      if (strn /= "abc") then
        if (present (xfail)) then
          print *, 'INVALID STRING - EXPECTED "abc" / PR47225' ! <<< PR is
wrong :-/
        else
          stop 32
        end if

The call has:

    scalar.4 = 97;   // that's  'a' -> expected: "abc".
    desc.3.dtype = {.elem_len=1, .rank=0, .type=1}; // not the elem_len=1;
should be len*kind
    desc.3.data = (void *) &scalar.4;
    desc.3.span = (integer(kind=8)) desc.3.dtype.elem_len;

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tobias Burnus <burnus@gcc.gnu.org>:

https://gcc.gnu.org/g:6920d5a1a2834e9c62d441b8f4c6186b01107d13

commit r12-4505-g6920d5a1a2834e9c62d441b8f4c6186b01107d13
Author: Tobias Burnus <tobias@codesourcery.com>
Date:   Tue Oct 19 15:16:01 2021 +0200

    Fortran: Fix "str" to scalar descriptor conversion [PR92482]

            PR fortran/92482
    gcc/fortran/ChangeLog:

            * trans-expr.c (gfc_conv_procedure_call): Use TREE_OPERAND not
            build_fold_indirect_ref_loc to undo an ADDR_EXPR.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/bind-c-char-descr.f90: Remove xfail; extend a bit.

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

Tobias Burnus <burnus at gcc dot gnu.org> changed:

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

--- Comment #10 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Close as FIXED (in GCC 12) now that also the remaining issue is solved :-)

Thanks again for the report!

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

sandra at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |everythingfunctional@proton
                   |                            |mail.com

--- Comment #11 from sandra at gcc dot gnu.org ---
*** Bug 99922 has been marked as a duplicate of this bug. ***

[Bug fortran/92482] BIND(C) with array-descriptor mishandled for type character

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92482

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0