[Issue 20802] [REG2.088.0] Link failure with writefln

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20802

--- Comment #7 from Iain Buclaw <ibuclaw at gdcproject.org> ---
(In reply to anonymous4 from comment #6)
> This looks like a rather fundamental collision between speculative
> instantiation and conditional compilation. __switch_errorT can't be in
> druntime unconditionally because its behavior changes depending on
> compilation options.
Because it's a weak symbol, any local instantiation would override the
unconditional instantiation in druntime.

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