https://issues.dlang.org/show_bug.cgi?id=23774

mhh <maxhaton@gmail.com> changed:

           What    |Removed                     |Added
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                 CC|                            |maxhaton@gmail.com

--- Comment #1 from mhh <maxhaton@gmail.com> ---
Part of the wtf is warning on inline failure by default.

dmd's IR seems to make some kind of inlining basically impossible in practice. The transformation is mathematically possible but has not been implemented (for such a fundamental concept as inlining)

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https://issues.dlang.org/show_bug.cgi?id=23774

--- Comment #2 from Rainer Schuetze <r.sagitario@gmx.de> ---
Something changed about the `__ctfe` branch in

```
union Split64
{
    ulong u64;
    uint lo;

    pragma(inline, true)
    this(ulong u64)
    {
        if (__ctfe)
            lo = cast(uint) u64;
        else
            this.u64 = u64;
    }
}

int foo(ulong v)
{
        const sv = Split64(v);
        return (sv.lo == 0);
}
```

If you replace `__ctfe` with `false` the wwarning disappears.

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