On Fri, 16 Nov 2018 at 18:46, Bjorn Reese via Boost-users
The upcoming 1.69 release of Boost.System has built-in support for std::error_code.
I was looking into this and got really confused. - I don't see any mention to that in https://www.boost.org/users/history/version_1_69_0.html - I guess it is https://github.com/boostorg/system/commit/6010be4144ce126e79a7eee56f5b40eef8..., but that has been there since 1.65 One "new" thing listed in the 1.69 release notes is "Boost.System is now header-only". But I can see a reference to BOOST_ERROR_CODE_HEADER_ONLY in Boost.System from 2012 (https://github.com/boostorg/system/commit/65e14ff1670ea4cf41fb31d989b31ce9d9...). And Chrono documentation has been documenting the "undocumented feature" (BOOST_ERROR_CODE_HEADER_ONLY) for a long time. Up to 1.54 it said "but it is buggy (see #7347 duplicate symbol while BOOST_ERROR_CODE_HEADER_ONLY is defined)", but that warning was removed in 1.55. So it looks like, - Boost.System has been getting header-only for years - Boost.Chrono has considered Boost.System header-only-ready since 1.55 - Boost.System considers itself header-only-ready since 1.69 - Boost.System has had built-in support for std::error_code since 1.65... but it has never been officially announced, so it's unclear how good that support is, including in the upcoming 1.69. Anybody has any more info about all this?