topic Re: Nested defined assignment not called with parameterized derived type in Intel® Fortran Compiler

Nested defined assignment not called with parameterized derived type

WileyOne — Fri, 27 Jun 2025 18:43:48 GMT

Compiler: ifx (IFX) 2025.2.0

OS: Rocky Linux 8.10 (Green Obsidian)

I've found a bug at the intersection of parameterized derived types and defined assignment, specifically when nested 3 classes deep. In the following code, the print statement should display, but it does not.

module Classes_Header implicit none type :: class1 integer :: ii contains generic, public :: assignment(=) => copy procedure, private :: copy end type type :: class2 type(class1) :: myClass1 end type type :: class3(n) integer, len :: n type(class2) :: myClass2 end type contains subroutine copy(lhs,rhs) class(class1), intent(out) :: lhs class(class1), intent(in) :: rhs lhs%ii = 7 print *, 'copy was called - worked as expected' end subroutine function constructor() result(this) type(class3(4)) :: this this%myClass2%myClass1%ii = 42 end function end module program main use Classes_Header implicit none type(class3(:)), allocatable :: myClass3 myClass3 = constructor() end program

Note that if class3 is not a parameterized derived type, the defined assignment is called as expected. This is true even if class3 remains an allocatable in the program main.

Re: Nested defined assignment not called with parameterized derived type

WileyOne — Fri, 27 Jun 2025 19:55:57 GMT

Note the similarities and differences between this and another issue I just updated. In both bugs, the defined assignment is not called. Here, the problem comes from the parameterized derived type, while the other issue is a nested class structure containing an `allocatable` class.

Re:Nested defined assignment not called with parameterized derived type

Ron_Green — Fri, 27 Jun 2025 19:58:19 GMT

Thank you for sending this to us. The bug ID is CMPLRLLVM-68773

Re: Nested defined assignment not called with parameterized derived type

WileyOne — Tue, 01 Jul 2025 12:06:24 GMT

Three other cases to add here. They are subtle differences from my original post, but I wanted to make sure these edge cases were caught. In short, the defined assignment is neither called when class3 is a class-allocatable nor when it extends from an abstract class nor when it's a type with the same parameter; see the attached files for specifics. I appended "TypeAllocatable_OriginalPost" onto the name of the file above for clarity, but it is the same otherwise.

@Ron_Green, should I make separate issues for these bugs or leave them as part of this one?

Re:Nested defined assignment not called with parameterized derived type

Igor_V_Intel — Thu, 15 Jan 2026 21:53:08 GMT

The fix is implemented and will be available in the next major compiler release.

Re: Re:Nested defined assignment not called with parameterized derived type

WileyOne — Fri, 16 Jan 2026 12:17:31 GMT

Thank you for the update, @Igor_V_Intel!

Re: Nested defined assignment not called with parameterized derived type

WileyOne — Wed, 06 May 2026 12:36:27 GMT

I have confirmed that this is working correctly with the latest compiler version (2026.0.0). Thank you, Intel team!