https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97037
Bug ID: 97037
Summary: ICE on user-defined derived-type output of an
intermediate ancestor type
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: damian at sourceryinstitute dot org
Target Milestone: ---
The code below effectively has an abstract parent type ("object"), abstract
child type ("oracle"), and a non-abstract grandchild type ("results_t") in
which the parent has a derived-type output binding, the child has a type-bound
operator(-) associated with a deferred binding ("negative"), and the grandchild
implements both deferred bindings. An ICE results when attempting to write the
result of the operator. Presumably the issue is that the grandchild's operator
result must be of the child type. The child type inherits the derived-type
output binding from the parent, but it doesn't itself explicitly state such a
binding. I lean toward thinking the code is valid, but I haven't yet consulted
the standard.
$ cat uddtio-ice.f90
module object_interface
implicit none
type, abstract :: object
contains
procedure(write_formatted_interface), deferred :: write_formatted
generic :: write(formatted) => write_formatted
end type
abstract interface
subroutine write_formatted_interface(this, unit, iotype, vlist, iostat,
iomsg)
import object
implicit none
class(object), intent(in) :: this
integer, intent(in) :: unit, vlist(:)
character(len=*), intent(in) :: iotype
integer, intent(out) :: iostat
character(len=*), intent(inout) :: iomsg
end subroutine
end interface
type, abstract, extends(object) :: oracle
contains
procedure(negative_interface), deferred :: negative
generic :: operator(-) => negative
end type
abstract interface
function negative_interface(this)
import oracle
implicit none
class(oracle), intent(in) :: this
class(oracle), allocatable :: negative_interface
end function
end interface
type, extends(oracle) :: results_t
contains
procedure write_formatted
procedure negative
end type
interface
module subroutine write_formatted(this, unit, iotype, vlist, iostat, iomsg)
implicit none
class(results_t), intent(in) :: this
integer, intent(in) :: unit, vlist(:)
character(len=*), intent(in) :: iotype
integer, intent(out) :: iostat
character(len=*), intent(inout) :: iomsg
end subroutine
module function negative(this)
implicit none
class(results_t), intent(in) :: this
class(oracle), allocatable :: negative
end function
end interface
end module
use object_interface
write(*,*) -results_t()
end program
$ gfortran -c uddtio-ice.f90
uddtio-ice.f90:61:0:
61 | write(*,*) -results_t()
|
internal compiler error: Segmentation fault: 11
$ gfortran --version
GNU Fortran (GCC) 11.0.0 20200804 (experimental)
