[Issue 19917] unions should require that all members are `= void` initialised

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19917

--- Comment #6 from Manu <turkeyman at gmail.com> ---
Either way. I like the `= void` personally. It's explicit, and there's no magic
rules to implement in the compiler.
It's also not always convenient to express a default construction.

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