incorrect generation of API doumentation in doxygen 1.8.13

[Bhumnay]

On generating documentation using doxygen 1.7 for docs/user/interface/Font.dox one can see all 5 operators under the class unicode_block but using latest version of doxygen 1.8.13 it lists 4 of them only-​https://www.haiku-os.org/docs/api/classunicode__block.html

[pulkomandy]

To be clear: the documentation of operator&() is missing from the generated docs. I have confirmed that this issue isn't there when generating with Doxygen 1.7.

I found this possibly related issue: ​https://github.com/doxygen/doxygen/issues/6295 with a similar fix shipped in Doxygen 1.8.15. We should confirm that it fixes the problem, and if it does, update our servers to use that version or a newer one to render api.haiku-os.org

[waddlesplash]

From the site build log:

10:00:30 PM: /opt/build/repo/haiku/docs/user/interface/Font.dox:476: warning: documented symbol `unicode_block unicode_block::operator &' was not declared or defined.
10:00:31 PM: /opt/build/repo/haiku/docs/user/interface/Rect.dox:692: warning: documented symbol `BRect BRect::operator &' was not declared or defined.
10:00:31 PM: /opt/build/repo/haiku/headers/os/interface/Font.h:358: warning: documented symbol `unicode_block unicode_block::operator &' was not declared or defined.

Indeed.

[pulkomandy]

We are now running Doxygen 1.8.16 and that fixed the problem.