Re: Bug 104404 - Incorrect CFI_cdesc_t "type" member for assumed-type, assumed-rank complex dummy arguments

[Paul Richard Thomas <paul.richard.thomas@gmail.com>]

Hi Damian,

Tobias Burnus fixed it in 12-branch:
GNU Fortran (GCC) 12.0.1 20220203 (experimental)
./a.out
 -----  complex(c_float_complex) --------
a_desc->type = 1028
a_desc->elem_len = 8
CFI_type_float_Complex = 1028
CFI_type_double_Complex = 2052
 -----  complex(c_double_complex) -------
a_desc->type = 2052
a_desc->elem_len = 16
CFI_type_float_Complex = 1028
CFI_type_double_Complex = 2052

Cheers

Paul


On Sun, 6 Feb 2022 at 03:39, Damian Rouson via Fortran <fortran@gcc.gnu.org>
wrote:

> For an assumed-type, assumed-rank complex dummy argument in a C interface,
> gfortran 11.2.0 passes a CFI_cdesc_t object with a "type" member that does
> not match the corresponding CFI_type_float_Complex and
> CFI_type_double_Complex values. In the case of a complex(c_float_complex)
> argument, the passed "type" member corresponds to CFI_type_double_Complex.
> For a complex(c_double_complex) argument, the "type" member has a value
> that I don't recognize.  Does anyone know whether this has been fixed on
> the 12 branch?
>
> % cat c_descriptor.c
> #include <stdio.h>
> #include <ISO_Fortran_binding.h>
>
> void c_descriptor(CFI_cdesc_t* c)
> {
>   printf("a_desc->type = %d \n", c->type);
>   printf("a_desc->elem_len = %d \n", c->elem_len);
>   printf("CFI_type_float_Complex = %d \n", CFI_type_float_Complex);
>   printf("CFI_type_double_Complex = %d \n", CFI_type_double_Complex);
> }
>
> % cat c_descriptor.c
> #include <stdio.h>
> #include <ISO_Fortran_binding.h>
>
> void c_descriptor(CFI_cdesc_t* c)
> {
>   printf("a_desc->type = %d \n", c->type);
>   printf("a_desc->elem_len = %d \n", c->elem_len);
>   printf("CFI_type_float_Complex = %d \n", CFI_type_float_Complex);
>   printf("CFI_type_double_Complex = %d \n", CFI_type_double_Complex);
> }
> (base) rouson@CLaSS adhoc % cat assumed-type.f90
> module c_descriptor_m
>   implicit none
> contains
>   module subroutine print_type_info(a)
>     type(*), intent(inout), contiguous, target :: a(..)
>
>     interface
>       subroutine c_descriptor(a) bind(C)
>         implicit none
>         type(*) a(..)
>       end subroutine
>     end interface
>
>     call c_descriptor(a)
>
>   end subroutine
> end module
>
>   use c_descriptor_m
>   use iso_c_binding
>   implicit none
>
>   complex(c_float_complex) :: z_float = (0._c_float, 0._c_float)
>   complex(c_double_complex):: z_double = (0._c_double, 0._c_double)
>
>   print*, "-----  complex(c_float_complex) --------"
>   call print_type_info(z_float)
>   print*, "-----  complex(c_double_complex) -------"
>   call print_type_info(z_double)
> end
>
>  % gfortran c_descriptor.c assumed-type.f90
>
> % ./a.out
>  -----  complex(c_float_complex) --------
> a_desc->type = 2052
> a_desc->elem_len = 8
> CFI_type_float_Complex = 1028
> CFI_type_double_Complex = 2052
>  -----  complex(c_double_complex) -------
> a_desc->type = 4100
> a_desc->elem_len = 16
> CFI_type_float_Complex = 1028
> CFI_type_double_Complex = 2052
>
> % gfortran --version
> GNU Fortran (Homebrew GCC 11.2.0_3) 11.2.0
>


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