Description:
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This feature request finds broken links. In other words, typically the following creates a link:

  <function>foo</function>

But if it doesn't then we have a problem... usually because foo should have been fooos.

This applies to others such as <methodname> too.

While building with PhD, these broken links may be reported to the builder depending on the verbosity of the error level. 

Depends on implementation, but I reckon a VERBOSE_BROKEN_LINKS in PhDErrors.php and format_function_text() in themes. Use VERBOSE_NOVERSION implementation as a guide.