[Issue 23972] class identity check is broken

Jun 05, 2023

Bolpat

Oct 16, 2023

Dlang Bot

Oct 17, 2023

Oct 17, 2023

Oct 19, 2023

Oct 20, 2023

Nov 14, 2023

Nov 14, 2023

Dec 16, 2023

https://issues.dlang.org/show_bug.cgi?id=23972 Bolpat <qs.il.paperinik@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |qs.il.paperinik@gmail.com --

https://issues.dlang.org/show_bug.cgi?id=23972 Dlang Bot <dlang-bot@dlang.rocks> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |pull --- Comment #1 from Dlang Bot <dlang-bot@dlang.rocks> --- @SixthDot created dlang/dmd pull request #15696 "fix issue 23972 - class identity check is broken" fixing this issue: - fix issue 23972 - class identity check is broken insert casts to Object when interfaces are used as IdentityExp operands https://github.com/dlang/dmd/pull/15696 --

https://issues.dlang.org/show_bug.cgi?id=23972 RazvanN <razvan.nitu1305@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED CC| |razvan.nitu1305@gmail.com Resolution|--- |INVALID --- Comment #2 from RazvanN <razvan.nitu1305@gmail.com> --- Thank you for taking the time of writing this bug report, however, as explained in this comment [1], the bug report is invalid. I1 and I2 are different types, therefore the is expression is correct in returning false. The fact that the pointer points to the same memory address is not relevant in this case since the compiler does not do any dataflow analysis to see where the interface was assigned. [1] https://github.com/dlang/dmd/pull/15696#pullrequestreview-1682054176 --

https://issues.dlang.org/show_bug.cgi?id=23972 Dennis <dkorpel@live.nl> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dkorpel@live.nl --- Comment #4 from Dennis <dkorpel@live.nl> --- I think the spec is wrong (or too vague) here. The interface object has a slightly different address than the class object, so the pointers aren't equal. `is` should be a simple bit compare, and not be doing casting logic for classes. --

October 20, 2023

[Issue 23972] class identity check is broken

Posted by Bolpat

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Bolpat

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https://issues.dlang.org/show_bug.cgi?id=23972

--- Comment #5 from Bolpat <qs.il.paperinik@gmail.com> ---
(In reply to Dennis from comment #4)
> I think the spec is wrong (or too vague) here. The interface object has a
> slightly different address than the class object, so the pointers aren't
> equal.
> `is` should be a simple bit compare, and not be doing casting logic for
> classes.

No, in this case, it shouldn't. If one actually wants to compare the pointer values, one can always cast to `void*` and compare the pointers. The fact that the class handles are represented by pointers is really an implementation detail. The current behavior is both surprising and useless. If the `is` operator does not provide class object identity, it should not be there at all; the error message in that case could point out that an explicit cast to Object is needed, but if that's what programmers will do anyways, why not provide something like an operator for it that does The Right Thing™?

--

https://issues.dlang.org/show_bug.cgi?id=23972 --- Comment #6 from Dlang Bot <dlang-bot@dlang.rocks> --- @dkorpel created dlang/dlang.org pull request #3726 "Fix 23972 - class identity check is broken" fixing this issue: - Fix 23972 - class identity check is broken https://github.com/dlang/dlang.org/pull/3726 --

https://issues.dlang.org/show_bug.cgi?id=23972 Dlang Bot <dlang-bot@dlang.rocks> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|REOPENED |RESOLVED Resolution|--- |FIXED --- Comment #7 from Dlang Bot <dlang-bot@dlang.rocks> --- dlang/dlang.org pull request #3726 "Fix 23972 - class identity check is broken" was merged into master: - 99530f59602022930f6c2e634f3809a03fd0c8b6 by Dennis Korpel: Fix 23972 - class identity check is broken https://github.com/dlang/dlang.org/pull/3726 --

https://issues.dlang.org/show_bug.cgi?id=23972 Basile-z <b2.temp@gmx.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dhasenan@gmail.com --- Comment #8 from Basile-z <b2.temp@gmx.com> --- *** Issue 19633 has been marked as a duplicate of this issue. *** --

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