# Can someone test this short code (compiler error?)
**URL:** https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121
**Category:** General
**Created:** [January 16, 2026, 5:24pm UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121 "2026-01-16T17:24:48Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@reinert](https://forum.ada-lang.io/u/reinert)
#### Post date: [January 16, 2026, 5:24pm UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/1 "2026-01-16T17:24:48Z")
Could someone test this code:
```ada
with Ada.Text_IO; use Ada.Text_IO;
procedure test1 is
type fam_rel1_t is (f_c, f_d1, f_d2, f_d3, f_d4, f_d5, f_d6);
for fam_rel1_t use (f_c=>1, f_d1=>2, f_d2=>3, f_d3=>4, f_d4=>5, f_d5=>6, f_d6=>7);
begin
for d in fam_rel1_t loop
if d /= f_c then
put_line("Here 1: " & d'Image);
end if;
end loop;
Put_Line("============================");
for d in fam_rel1_t when d /= f_c loop
put_line("Here 2: " & d'Image);
end loop;
end test1;
```
I get this output when I include “for .. use”:
Here 1: F\_D1
Here 1: F\_D2
Here 1: F\_D3
Here 1: F\_D4
Here 1: F\_D5
Here 1: F\_D6
=====================================
Here 2: F\_C
Here 2: F\_D1
Here 2: F\_D2
Here 2: F\_D3
Here 2: F\_D4
Here 2: F\_D5
Here 2: F\_D6
I use latest version of debian and alire.
---
### Author:  [@pmnw](https://forum.ada-lang.io/u/pmnw)
#### Post date: [January 16, 2026, 6:11pm UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/2 "2026-01-16T18:11:29Z")
Here you go: [Compiler Explorer](https://godbolt.org/z/b3sjeY1r3)
(I changed the procedure name to `example` because of some Godbolt peculiarities)
Edit:
a sounder example: [Compiler Explorer](https://godbolt.org/z/5v5q4PvqP)
---
### Author:  [@Irvise](https://forum.ada-lang.io/u/Irvise)
#### Post date: [January 16, 2026, 7:26pm UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/3 "2026-01-16T19:26:54Z")
I changed the compiler to truck and it does the same! Wierd! Mmmmm… This looks like a compiler bug… I think this should be reported to upstream.
---
### Author:  [@charlie5](https://forum.ada-lang.io/u/charlie5)
#### Post date: [January 17, 2026, 4:23am UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/4 "2026-01-17T04:23:47Z")
Same result on Arch gcc version 15.2.1 20260103.
I’ve never seen a ‘when’ in a ‘for’ loop like that before. Is it a new 2022 addition ?
---
### Author:  [@reinert](https://forum.ada-lang.io/u/reinert)
#### Post date: [January 17, 2026, 6:42am UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/5 "2026-01-17T06:42:02Z")
I made an illegal construct (without getting an error message) ?
Note that “for .. use” has an effect. Try to comment it out (or remove it).
---
### Author:  [@Irvise](https://forum.ada-lang.io/u/Irvise)
#### Post date: [January 17, 2026, 8:48am UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/6 "2026-01-17T08:48:59Z")
> [@charlie5](#):
>
> I’ve never seen a ‘when’ in a ‘for’ loop like that before. Is it a new 2022 addition ?
Yup! It is new syntax 🙂
> [@reinert](#):
>
> Note that “for .. use” has an effect. Try to comment it out (or remove it).
Afaik, it is only a representation clause, so it should not affect the logic…
---
### Author:  [@pmnw](https://forum.ada-lang.io/u/pmnw)
#### Post date: [January 17, 2026, 9:24am UTC](https://forum.ada-lang.io/t/can-someone-test-this-short-code-compiler-error/4121/7 "2026-01-17T09:24:58Z")
Has already been reported some time ago:
> **[121316 – representation clause on enumeration type causes iterator filters to...](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121316)**