https://issues.dlang.org/show_bug.cgi?id=23587

Iain Buclaw <ibuclaw@gdcproject.org> changed:

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                 CC|                            |ibuclaw@gdcproject.org

--- Comment #1 from Iain Buclaw <ibuclaw@gdcproject.org> ---
I suspect introduced by https://github.com/dlang/dmd/pull/14494

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https://issues.dlang.org/show_bug.cgi?id=23587

Dlang Bot <dlang-bot@dlang.rocks> changed:

           What    |Removed                     |Added
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           Keywords|                            |pull

--- Comment #2 from Dlang Bot <dlang-bot@dlang.rocks> ---
@ibuclaw updated dlang/dmd pull request #14758 "Revert "Fix Issues 23331, 23379 - fix casts involving noreturn"" fixing this issue:

- fix Issue 23587 - cast(void) doesn't work for noreturn

https://github.com/dlang/dmd/pull/14758

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https://issues.dlang.org/show_bug.cgi?id=23587

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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           Keywords|                            |rejects-valid

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https://issues.dlang.org/show_bug.cgi?id=23587

RazvanN <razvan.nitu1305@gmail.com> changed:

           What    |Removed                     |Added
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                 CC|                            |razvan.nitu1305@gmail.com

--- Comment #3 from RazvanN <razvan.nitu1305@gmail.com> ---
Why does it matter? The call to fun will never return so casting to void (or any other value) it actually a no-op.

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https://issues.dlang.org/show_bug.cgi?id=23587

--- Comment #4 from Iain Buclaw <ibuclaw@gdcproject.org> ---
(In reply to RazvanN from comment #3)
> Why does it matter? The call to fun will never return so casting to void (or any other value) it actually a no-op.
The devils in the detail of the change, not the example code in this bug report.  By blowing a hole in the type system has opened up the flood gates to even worse abominations being accepted.

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https://issues.dlang.org/show_bug.cgi?id=23587

Iain Buclaw <ibuclaw@gdcproject.org> changed:

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           See Also|                            |https://issues.dlang.org/sh
                   |                            |ow_bug.cgi?id=23591

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https://issues.dlang.org/show_bug.cgi?id=23587

--- Comment #5 from artha@samerion.com ---
(In reply to RazvanN from comment #3)
> Why does it matter? The call to fun will never return so casting to void (or any other value) it actually a no-op.

In this case it makes the compiler issue an unwanted warning. The cast is supposed to tell the compiler I'm purposefully discarding the return value.

As a workaround, I could've done this:

```
fun();
static if (!is(typeof(stuff()) == void)) {
    writeln("never written");
}
```

But it's a mess, and I don't want to do that every time I call a template delegate.

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https://issues.dlang.org/show_bug.cgi?id=23587

--- Comment #6 from Iain Buclaw <ibuclaw@gdcproject.org> ---
(In reply to artha from comment #5)
> (In reply to RazvanN from comment #3)
> > Why does it matter? The call to fun will never return so casting to void (or any other value) it actually a no-op.
> 
> In this case it makes the compiler issue an unwanted warning. The cast is supposed to tell the compiler I'm purposefully discarding the return value.
> 

You're not wrong. cast(void) bottom is completely valid and the result should
be void.

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https://issues.dlang.org/show_bug.cgi?id=23587

Dlang Bot <dlang-bot@dlang.rocks> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #7 from Dlang Bot <dlang-bot@dlang.rocks> ---
dlang/dmd pull request #14758 "Revert "Fix Issues 23331, 23379 - fix casts involving noreturn"" was merged into master:

- 8bf1c8dab73adb9b990be334cdde1a068cb0a71e by Iain Buclaw:
  fix Issue 23587 - cast(void) doesn't work for noreturn

https://github.com/dlang/dmd/pull/14758

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