August 28
https://issues.dlang.org/show_bug.cgi?id=24730

--- Comment #1 from Max Samukha <maxsamukha@gmail.com> ---
Works with an explicit cast:

ref S s = cast(S)s2;

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December 13
https://issues.dlang.org/show_bug.cgi?id=24730

--- Comment #2 from dlangBugzillaToGithub <robert.schadek@posteo.de> ---
THIS ISSUE HAS BEEN MOVED TO GITHUB

https://github.com/dlang/dmd/issues/20504

DO NOT COMMENT HERE ANYMORE, NOBODY WILL SEE IT, THIS ISSUE HAS BEEN MOVED TO GITHUB

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