id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
11582,Regression with -Woverloaded-virtual in unit_test_log_t,Ben Wiederhake <Ben.Wiederhake@…>,Gennadiy Rozental,"While trying to compile my code with ""-Woverloaded-virtual -Werror"", I
found a shortcoming, possibly even a bug.

In 1.59.0 (and, as far as I can see in git, all following versions),
there are the following declarations/definitions:

{{{
class test_observer /* boost/test/tree/observer.hpp:40 */
virtual void test_unit_skipped( test_unit const& tu, const_string)
   { test_unit_skipped( tu ); }
virtual void test_unit_skipped( test_unit const& )
   {} ///< backward compartibility

class unit_test_log_t /* boost/test/unit_test_log.hpp:97 */
virtual void test_unit_skipped( test_unit const&, const_string );
/* Actually uses the message in the implementation */
/* Does not override Test_unit_skipped( test_unit const& ) */
}}}

The problem with this code is that code like the following simply will
not work:

{{{
unit_test_log_t& foobar;
test_unit const& tu;
foobar.test_unit_skipped( tu ); // <-- Error!
}}}

g++ would say ""candidate expects 2 arguments, 1 provided"". clang++ is a
tad more helpful, and would say: ""too few arguments to function call,
expected 2, have 1; did you mean 'test_observer::test_unit_skipped'?""
In case you're unfamiliar with that behaviour, see this specific answer:
http://stackoverflow.com/a/6035884/3070326
(Error messages are from a different compilation, but should be the same.)

I hope I have now established that -Woverloaded-virtual ""has a point"".

I don't fully understand why unit_test_log_t doesn't override the
other signature, too; but it should be easily possible to override
it with something like:

{{{
test_unit_skipped( tu, ""<No message>"" );
}}}

However, I do not yet fully understand the context of unit_test_log_t,
so maybe such a call cannot occur. That's why I'm unable to make a
patch from that idea.

At the very least, this issue is annoying for people who use Boost.Test
and try to compile with -Woverloaded-virtual.

Note that Boost.Test 1.58.0 did *not* exhibit this issue, so I felt free
to put ""regression"" in the subject and 'severity'.

(PS: Thanks to Rene Rivera for redirecting me away from the mailing list,
and  Raffi Enficiaud for redirecting me to this trac.)
",Bugs,closed,To Be Determined,test,Boost Development Trunk,Problem,wontfix,,