On Thu, Dec 14, 2017 at 7:03 AM, Daniel James via Boost-users <boost-users@lists.boost.org> wrote:
The second release candidates for the 1.66.0 release are now available at:

<https://dl.bintray.com/boostorg/prerelease/>

The in progress release notes are:

<http://www.boost.org/users/history/in_progress.html>

Library documentation is available at:

<http://www.boost.org/doc/libs/1_66_0/>

The SHA256 checksums are as follows:

596389389c005814ecb2a6b64c31dccd2c3e6fbc5a802b4dfada999ae5844628
boost_1_66_0_rc2.7z
5721818253e6a0989583192f96782c4a98eb6204965316df9f5ad75819225ca9
boost_1_66_0_rc2.tar.bz2
bd0df411efd9a585e5a2212275f8762079fed8842264954675a4fddc46cfcf60
boost_1_66_0_rc2.tar.gz
e1c55ebb00886c1a96528e4024be98a38b815115f62ecfe878fcf587ba715aad
boost_1_66_0_rc2.zip

As always, the release managers would appreciate it if you download
the candidate of your choice and give building it a try. Please report
both success and failure, and anything else that is noteworthy.

Windows builds look good.

toolset     arch    compile Link    Execute 
msvc-8.0    32      X       X       X 
msvc-8.0    64      X       X       X 
msvc-9.0    32      X       X       X 
msvc-9.0    64      X       X       X 
msvc-10.0   32      X       X       X 
msvc-10.0   64      X       X       X 
msvc-11.0   32      X       X       X 
msvc-11.0   64      X       X       X 
msvc-12.0   32      X       X       X 
msvc-12.0   64      X       X       X 
msvc-14.0   32      X       X       X 
msvc-14.0   64      X       X       X 
msvc-14.1   32      X       X       X 
msvc-14.1   64      X       X       X 

Compile means that the b2 command completed without errors 
Link means that visual studio was able to link a sample executable to a library (libboost_thread-vcXXX-mt[-gd]-1_XX.lib)
generated 
Execute means that the linked program executed without errors.

Tom