https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125528
Bug ID: 125528
Summary: ICE or wrong-code for ASSOCIATE selector that is a
type-bound user-defined operator
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: jvdelisle at gcc dot gnu.org
Target Milestone: ---
gfortran fails to compile ASSOCIATE constructs whose
selector is a type-bound user-defined operator (UDO)
expression. Three related cases are affected:
1. A direct type-bound UDO as the selector
(associate (g => .grad. s)).
2. An inherited UDO defined on a parent type
(associate (q => .sq. s)).
3. Nested UDO expressions
(associate (r => .div. (.grad. s))).
In case 1 gfortran produces an ICE ("Syntax error in
expression") inside the ASSOCIATE body because the
associate variable is left without a type. Cases 2 and 3
produce similar failures. Intel Fortran and NAG Fortran
accept all three cases.
module m
implicit none
type :: scalar_t
real :: val
contains
generic :: operator(.grad.) => do_grad
procedure, private :: do_grad
generic :: operator(.sq.) => do_sq
procedure, private :: do_sq
generic :: get => get_val
procedure :: get_val
end type
type, extends(scalar_t) :: vector_t
contains
generic :: operator(.div.) => do_div
procedure, private :: do_div
end type
contains
pure function do_grad (self) result (r)
class(scalar_t), intent(in) :: self
type(vector_t) :: r
r%val = self%val * 2.0
end function
pure function do_sq (self) result (r)
class(scalar_t), intent(in) :: self
type(scalar_t) :: r
r%val = self%val * self%val
end function
pure function do_div (self) result (r)
class(vector_t), intent(in) :: self
type(scalar_t) :: r
r%val = self%val / 2.0
end function
pure function get_val (self) result (r)
class(scalar_t), intent(in) :: self
real :: r
r = self%val
end function
end module m
program p
use m
implicit none
type(scalar_t) :: s
s%val = 3.0
associate (g => .grad. s) ! case 1
if (abs (g%val - 6.0) > 1.0e-6) stop 1
end associate
associate (q => .sq. s) ! case 2
if (abs (q%val - 9.0) > 1.0e-6) stop 2
end associate
associate (r => .div. (.grad. s)) ! case 3
if (abs (r%val - 3.0) > 1.0e-6) stop 3
end associate
end program p
$ gfortran associate.f90
gfortran ICEs or rejects the code. The program should
compile and run cleanly.
