gfortran recent trunk r227512 does not invoke the finalizer for the intrinsic assignment (as required by F2008 4.5.6.3p9) to the array section of `b` in the following example: module tes_final_mod implicit none type :: my_final integer :: n = 0 contains final :: destroy_rank1_array end type my_final contains subroutine destroy_rank1_array(self) type(my_final), intent(inout) :: self(:) if (size(self) /= 0) then print "(A,I0,A,*(I0,:,', '))", & 'destroy_rank1_array executed for object of size ', & size(self), & ' and component values ', & self%n else print "(A)", & 'destroy_rank1_array executed for object of size 0' end if end subroutine destroy_rank1_array end module tes_final_mod program test_finalizer use tes_final_mod implicit none type(my_final) :: b(4), c(2) b%n = 2 c%n = 3 b(1:2) = c end program test_finalizer No output is generated, while expected output is: destroy_rank1_array executed for object of size 2 and component values 2,2 See also https://software.intel.com/en-us/forums/intel-fortran-compiler-for-linux-and-mac-os-x/topic/591918#comment-1838428
Confirmed from 4.9 up to trunk (6.0). Added to the list of PRs blocking pr37336 (I let you check that it is not a duplicate).
The master branch has been updated by Paul Thomas <pault@gcc.gnu.org>: https://gcc.gnu.org/g:d7caf313525a46f200d7f5db1ba893f853774aee commit r13-6747-gd7caf313525a46f200d7f5db1ba893f853774aee Author: Paul Thomas <pault@gcc.gnu.org> Date: Sat Mar 18 07:56:23 2023 +0000 Fortran: Fix bugs and missing features in finalization [PR37336] 2023-03-18 Paul Thomas <pault@gcc.gnu.org> gcc/fortran PR fortran/103854 PR fortran/96122 PR fortran/37336 * class.cc (finalize_component): Include the missing arguments in the call to the component's finalizer wrapper. (has_finalizer_component): Do not return true for procedure pointer components. (finalizer_insert_packed_call): Remove the redundant argument in the call to the final subroutine. (generate_finalization_wrapper): Add support for assumed rank finalizers. (gfc_may_be_finalized): New helper function. * dump-parse-tree.cc (write_proc): Whitespace. * gfortran.h : Add prototype for gfc_may_be_finalized. * resolve.cc (resolve_function): Correct derived types that have an incomplete namespace. (resolve_where, gfc_resolve_where_code_in_forall, gfc_resolve_forall_body, gfc_resolve_code): Check that the op code is still EXEC_ASSIGN. If it is set lhs to must finalize. (is_finalizable_type): New function. (generate_component_assignments): Set must_finalize if needed. (gfc_resolve_finalizers): Error if assumed rank finalizer is not the only one. Warning on lack of scalar finalizer modified to account for assumed rank finalizers. (generate_final_call): New function. (generate_component_assignments): Enclose the outermost call in a block to capture automatic deallocation and final calls. Set must_finalize as required to satisfy the standards. Use an explicit pointer assignment for pointer components to capture finalization of the target. Likewise use explicit assignment for allocatable components. Do not use the temporary copy of the lhs in defined assignment if the component is allocatable. Put the temporary in the same namespace as the lhs symbol if the component may be finalized. Remove the leading assignment from the expansion of assignment of components that have their own defined assignment components. Suppress finalization of assignment of temporary components to the lhs. Make an explicit final call for the rhs function temporary if it exists. (gfc_resolve_code): Set must_finalize for assignments with an array constructor on the rhs. (gfc_resolve_finalizers): Ensure that an assumed rank finalizer is the only finalizer for that type and correct the surprising warning for the lack of a scalar finalizer. (check_defined_assignments): Handle allocatable components. (resolve_fl_derived): Set referenced the vtab for use associated symbols. (resolve_symbol): Set referenced an unreferenced symbol that will be finalized. * trans-array.cc (gfc_trans_array_constructor_value): Add code to finalize the constructor result. Warn that this feature was removed in F2018 and that it is suppressed by -std=2018. (trans_array_constructor): Add finalblock, pass to previous and apply to loop->post if filled. (gfc_add_loop_ss_code): Add se finalblock to outer loop post. (gfc_trans_array_cobounds, gfc_trans_array_bounds): Add any generated finalization code to the main block. (structure_alloc_comps): Add boolean argument to suppress finalization and use it for calls from gfc_deallocate_alloc_comp_no_caf. Otherwise it defaults to false. (gfc_copy_alloc_comp_no_fini): New wrapper for structure_alloc_comps. (gfc_alloc_allocatable_for_assignment): Suppress finalization by setting new arg in call to gfc_deallocate_alloc_comp_no_caf. (gfc_trans_deferred_array): Use gfc_may_be_finalized and do not deallocate the components of entities with a leading '_' in the name that are also marked as artificial. * trans-array.h : Add the new boolean argument to the prototype of gfc_deallocate_alloc_comp_no_caf with a default of false. Add prototype for gfc_copy_alloc_comp_no_fini. * trans-decl.cc(init_intent_out_dt): Tidy up the code. * trans-expr.cc (gfc_init_se): Initialize finalblock. (gfc_conv_procedure_call): Use gfc_finalize_tree_expr to finalize function results. Replace in-line block for class results with call to new function. (gfc_conv_expr): Finalize structure constructors for F2003 and F2008. Warn that this feature was deleted in F2018 and, unlike array constructors, is not default. Add array constructor finalblock to the post block. (gfc_trans_scalar_assign): Suppress finalization by setting new argument in call to gfc_deallocate_alloc_comp_no_caf. Add the finalization blocks to the main block. (gfc_trans_arrayfunc_assign): Use gfc_assignment_finalizer_call and ensure that finalization occurs after the evaluation of the rhs but using the initial value for the lhs. Finalize rhs function results using gfc_finalize_tree_expr. (trans_class_assignment, gfc_trans_assignment_1): As previous function, taking care to order evaluation, assignment and finalization correctly. * trans-io.cc (gfc_trans_transfer): Add the final block. * trans-stmt.cc (gfc_trans_call, gfc_trans_allocate): likewise. (trans_associate_var): Nullify derived allocatable components and finalize function targets with defined assignment components on leaving the block scope. (trans_allocate): Finalize source expressions, if required, and set init_expr artificial temporarily to suppress the finalization in gfc_trans_assignment. * trans.cc (gfc_add_finalizer_call): Do not finalize the temporaries generated in type assignment with defined assignment components. (gfc_assignment_finalizer_call): New function. (gfc_finalize_tree_expr): New function. * trans.h: Add finalblock to gfc_se. Add the prototypes for gfc_finalize_tree_expr and gfc_assignment_finalizer_call. gcc/testsuite/ PR fortran/64290 * gfortran.dg/finalize_38.f90 : New test. * gfortran.dg/finalize_38a.f90 : New test. * gfortran.dg/allocate_with_source_25.f90 : The number of final calls goes down from 6 to 4. * gfortran.dg/associate_25.f90 : Remove the incorrect comment. * gfortran.dg/auto_dealloc_2.f90 : Change the tree dump expr but the final count remains the same. * gfortran.dg/unlimited_polymorphic_8.f90 : Tree dump reveals foo.1.x rather than foo.0.x PR fortran/67444 * gfortran.dg/finalize_39.f90 : New test. PR fortran/67471 * gfortran.dg/finalize_40.f90 : New test. PR fortran/69298 PR fortran/70863 * gfortran.dg/finalize_41.f90 : New test. PR fortran/71798 * gfortran.dg/finalize_42.f90 : New test. PR fortran/80524 * gfortran.dg/finalize_43.f90 : New test. PR fortran/82996 * gfortran.dg/finalize_44.f90 : New test. PR fortran/84472 * gfortran.dg/finalize_45.f90 : New test. PR fortran/88735 PR fortran/93691 * gfortran.dg/finalize_46.f90 : New test. PR fortran/91316 * gfortran.dg/finalize_47.f90 : New test. PR fortran/106576 * gfortran.dg/finalize_48.f90 : New test. PR fortran/37336 * gfortran.dg/finalize_49.f90 : New test. * gfortran.dg/finalize_50.f90 : New test. * gfortran.dg/finalize_51.f90 : New test.
This is fixed on mainline. I will ask if I can backport to 12-branch in a few weeks. Cheers Paul