Hi Everyone, I need the advice from the experts, on what is the recommended way to handle the following situation with regression tests. A number of tests of Boost.Optional fail. (see here: http://www.boost.org/development/tests/develop/developer/optional.html) These are the failures in optional<T&> (optional references), because quite a lot of compilers implement reference binding in a non-standard-conforming manner. (For details of these bugs see here: http://www.boost.org/doc/libs/develop/libs/optional/doc/html/boost_optional/... ). The question is, how these testing failures should be reflected in regression testing configuration, so that they do not appear as bugs in the implementation of Boost.Optional? 1. I hear that marking explicit failures is not recommended, and build config based on Boost.Config should be preferred. Also, the markup will not work because from the toolset name alone I cannot make the decision whether to mark the explicit failure or not. 2. On the other hand, I hear that Boost.config should not be used to detect any bug in a compiler that is relevant only to a single Boost library. These two pieces of advice appear contradictory in my case. I would like to abide to the recommendations in Boost, but in this case it appears that I am stuck. Is there any recommendation in such case for Boost developers? Regards, &rzej