# Function \`associated\` bug for Intel Fortran compiler?

**URL:** <https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730>\
**Category:** Help\
**Created:** [June 12, 2022, 10:19am UTC](https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730 "2022-06-12T10:19:42Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![zoziha](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/zoziha/32/582_2.png) [@zoziha](https://fortran-lang.discourse.group/u/zoziha)\
**Post date:** [June 12, 2022, 10:19am UTC](https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730/1 "2022-06-12T10:19:42Z")

</div>

Initially, in the process of learning `procedure pointer`, I made the following attempt:

```fortran
module test_m

    implicit none
    private

    public :: f, set_method

    ! local procedure pointer
    procedure(func), pointer :: f

    abstract interface
        function func(x)
            character(*), intent(in) :: x
            character(:), allocatable :: func
        end function func
    end interface

contains

    ! set method
    subroutine set_method(ifunc)
        integer, intent(in) :: ifunc
        if (ifunc == 1) then
            if (.not. associated(f, starts)) f => starts ! This line 👈
        elseif (ifunc == 2) then
            !...
        end if
    end subroutine set_method

    function starts(x)
        character(*), intent(in) :: x
        character(:), allocatable :: starts
        starts = ">"//x
    end function starts

end module test_m

program main

    use test_m
    implicit none

    call set_method(1)
    print *, f("string")

end program main

```

This code works fine on `gfortran` and `flang(old)`, returning the result:

```auto
 >string

```

But it fails on `ifort`:

```nohighlight
/app/example.f90: catastrophic error: **Internal compiler error: segmentation violation signal raised** Please report this error along with the circumstances in which it occurred in a Software Problem Report. Note: File and line given may not be explicit cause of this error.
compilation aborted for /app/example.f90 (code 1)

```

`ifx` shows that `associated` is not implemented:

> **ifx error**
>
> ```nohighlight
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x1376b6a]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10126fd]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x106beb2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x106be86]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0xfb2f5d]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0xfa9606]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10f19a5]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10f44e7]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10ea90e]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x106e741]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x1072233]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x104d5a1]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x104d407]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x104e26d]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10ba5c4]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bcea2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bd51c]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10ba687]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bcea2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bd51c]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bf79d]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bcea2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bd51c]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bac32]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bcea2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10ba34a]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x10bcea2]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0xf80496]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0xf7fc24]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0x11065be]
> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3)[0x7f0b682ce0b3]
> /opt/compiler-explorer/intel-fortran-2021.4.0.3224/compiler/2021.4.0/linux/bin/xfortcom[0xd9d2a9]
> 
> /app/example.f90(24): error #5533: Feature found on this line is not yet supported in ifx 
> if (.not. associated(f, starts)) f => starts
> ------------^
> compilation aborted for /app/example.f90 (code 3)
> 
> ```

**Remove the `associated` judgment , the code runs normally on all these compilers.**

> **no-associated judgment**
>
> ```fortran
> module test_m
> 
> implicit none
> private
> 
> public :: f, set_method
> 
> ! local procedure pointer
> procedure(func), pointer :: f
> 
> abstract interface
> function func(x)
> character(*), intent(in) :: x
> character(:), allocatable :: func
> end function func
> end interface
> 
> contains
> 
> ! set method
> subroutine set_method(ifunc)
> integer, intent(in) :: ifunc
> if (ifunc == 1) then
> f => starts ! Note here 👈
> elseif (ifunc == 2) then
> !...
> end if
> end subroutine set_method
> 
> function starts(x)
> character(*), intent(in) :: x
> character(:), allocatable :: starts
> starts = ">"//x
> end function starts
> 
> end module test_m
> 
> program main
> 
> use test_m
> implicit none
> 
> call set_method(1)
> print *, f("string")
> 
> end program main
> 
> ```

Online compiler: [Compiler Explorer (godbolt.org)](https://godbolt.org/)

Update: [ICE: Function `associated` bug for Intel Fortran compiler (ifort)? - Intel Communities](https://community.intel.com/t5/Intel-Fortran-Compiler/ICE-Function-associated-bug-for-Intel-Fortran-compiler-ifort/m-p/1391864#M161676)

---

<div class="post-metadata">

**Author:** ![septc](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/septc/32/77_2.png) [@septc](https://fortran-lang.discourse.group/u/septc)\
**Post date:** [June 12, 2022, 1:06pm UTC](https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730/2 "2022-06-12T13:06:03Z")

</div>

Making a function pointer (`starts_p`) somewhere (as a local or module variable) and using it in the `associated` statement worked for me with ifort-2021.6 + Ubuntu20.

```fortran
subroutine set_method(ifunc)
    integer, intent(in) :: ifunc

    procedure(starts), pointer :: starts_p => starts !! (*)

    if (ifunc == 1) then
        if (.not. associated(f, starts_p)) f => starts !! (*)

```

But declaring it as `procedure(func), pointer` gave an error like

```auto
test.f90(13): error #6303: The assignment operation
or the binary expression operation is invalid for
the data types of the two operands. [STARTS]
    procedure(func), pointer :: starts_p => starts

```

which I cannot understand…

Anyway, I guess the internal compiler error (ICE) is an issue of the compiler (to be hopefully reported), regardless of the contents of the code itself.

---

<div class="post-metadata">

**Author:** ![FortranFan](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@FortranFan](https://fortran-lang.discourse.group/u/FortranFan)\
**Post date:** [June 12, 2022, 1:43pm UTC](https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730/3 "2022-06-12T13:43:37Z")

</div>

@zoziha ,

As you will know, an internal compiler error can be viewed as a compiler bug regardless of any other considerations as to whether the code conforms, etc. As such, compiler developers are generally keen to get such errors reported to them.

So you may want to post this at the Intel Fortran forum as well; Intel Software Team follows up on such posts and forwards them to the Fortran team as appropriate:

> **[Intel® Fortran Compiler](https://community.intel.com/t5/Intel-Fortran-Compiler/bd-p/fortran-compiler)**
>
> Build applications that can scale for the future with optimized code designed for Intel® Xeon® and compatible processors.

---

<div class="post-metadata">

**Author:** ![greenrongreen](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/greenrongreen/32/1249_2.png) [@greenrongreen](https://fortran-lang.discourse.group/u/greenrongreen)\
**Post date:** [June 14, 2022, 10:40pm UTC](https://fortran-lang.discourse.group/t/function-associated-bug-for-intel-fortran-compiler/3730/4 "2022-06-14T22:40:32Z")

</div>

We opened a bug report CMPLRIL0-34800. Thanks for sending this over to the Intel Fortran Community Forum.