Symbol Undefined: _D4....__ModuleInfoZ

[%u]

== Quote from Rainer Schuetze (r.sagitario at gmx.de)'s article
> The static module constructor causes your module to take part in
the
> module initialization phase, so it creates a data structure that
> contains info about modules which are imported and should be
initialized
> first (referenced directly or maybe indirectly, if an imported
module
> does not have static constructors on it's own).
> The symbol above is the module info struct for core.stdc.stdio.

After playing with it it turned out that it was because the imported
modules weren't compiled in my project.

Not sure if that's a bug or not (it doesn't make much sense to be
forced to compile an external declaration...) but that was the
issue.