https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82312
Bug ID: 82312
Summary: Pointer assignment to component of class variable
results wrong vptr for the variable.
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: pault at gcc dot gnu.org
Target Milestone: ---
Posted on Stack Overflow:
https://stackoverflow.com/questions/46369744/gfortran-associates-wrong-type-bound-procedure/46388339#46388339
module minimalisticcase
implicit none
type, public :: DataStructure
integer :: i
contains
procedure, pass :: init => init_data_structure
procedure, pass :: a => beginning_of_alphabet
end type
type, public :: DataLogger
type(DataStructure), pointer :: data_structure
contains
procedure, pass :: init => init_data_logger
procedure, pass :: do_something => do_something
end type
contains
subroutine init_data_structure(self)
implicit none
class(DataStructure), intent(inout) :: self
write(*,*) 'init_data_structure'
end subroutine
subroutine beginning_of_alphabet(self)
implicit none
class(DataStructure), intent(inout) :: self
write(*,*) 'beginning_of_alphabet'
end subroutine
subroutine init_data_logger(self, data_structure)
implicit none
class(DataLogger), intent(inout) :: self
class(DataStructure), target :: data_structure
write(*,*) 'init_data_logger'
self%data_structure => data_structure
call self%do_something()
end subroutine
subroutine do_something(self)
implicit none
class(DataLogger), intent(inout) :: self
write(*,*) 'do_something'
end subroutine
end module
program main
use minimalisticcase
implicit none
type(DataStructure) :: data_structure
type(DataLogger) :: data_logger
call data_structure%init()
call data_logger%init(data_structure)
end program
produces
init_data_structure
init_data_logger
beginning_of_alphabet
rather than
init_data_structure
init_data_logger
do_something
The tree dump reveals that the vptr of 'self' is being set to the address of
the 'DataStructure' vtable.
Paul
