https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112316
Bug ID: 112316
Summary: [13 Regression] Fix for PR87477 rejects valid code
with a bogus error about pointer assignment and causes
an ICE
Product: gcc
Version: 13.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: trnka at scm dot com
Target Milestone: ---
Current releases/gcc-13 rejects the following testcase (compiled simply using
gfortran -c test-bogus-pointer-arg-error.f90):
===== test-bogus-pointer-arg-error.f90 =====
module BogusPointerArgError
implicit none
type :: AType
end type
contains
subroutine A ()
class(AType), allocatable :: x
allocate(x)
call B (x)
end subroutine
subroutine B (y)
class(AType), intent(in) :: y
end subroutine
subroutine C (z)
class(AType), intent(in) :: z(:)
associate (xxx => z(1))
end associate
end subroutine
end module
==========
14 | call B (x)
| 1
Error: Actual argument for ‘y’ at (1) must be a pointer or a valid target for
the dummy pointer in a pointer assignment statement
Apparently, both the associate block in C (which is never called) and routines
A and B need to be present to trigger the issue. It also seems to only happen
when "x" is polymorphic (class(AType)).
A related testcase is also rejected, this time with an ICE:
===== test-ICE-get_descriptor_field.f90 =====
module AModule
implicit none
private
public AType
type, abstract :: AType
contains
generic, public :: assignment(=) => Assign
procedure, private :: Assign
end type AType
contains
subroutine Assign(lhs, rhs)
class(AType), intent(inout) :: lhs
class(AType), intent(in) :: rhs
end subroutine
end module AModule
module ICEGetDescriptorField
use AModule
implicit none
contains
subroutine Foo (x)
class(AType), intent(in) :: x(:)
class(AType), allocatable :: y
associate (xxx => x(1))
y = xxx
end associate
end subroutine
end module ICEGetDescriptorField
==========
test-ICE-get_descriptor_field.f90:38:16:
38 | y = xxx
| 1
internal compiler error: in gfc_get_descriptor_field, at
fortran/trans-array.cc:245
This time, AType needs to be in a separate module and have a defined assignment
to trigger the bug.
Both issues bisect to the following commit. Reverting this change on top of
current releases/gcc-13 makes both issues go away. (GCC 14 is likely also
affected, not tested.)
https://gcc.gnu.org/g:d6997a5aab7aaa325946a6283bfee8ac2bd9f540
commit r13-7761-gd6997a5aab7aaa325946a6283bfee8ac2bd9f540
Author: Paul Thomas <pa...@gcc.gnu.org>
Date: Sun Aug 27 09:51:32 2023 +0100
Fortran: Fix some problems blocking associate meta-bug [PR87477]
