I am completely unable to build Boost libraries. I have been building on this same computer for many years, so this issue is confounding to me. I'm posting here in the hope that this peculiar error message might ring a bell with someone.

After bootstrapping, when executing "b2.exe", before getting into the actual build (which fails), these error messages are repeated multiple times:

error: No best alternative for ./headers
    next alternative: required properties: (empty)
        matched
    next alternative: required properties: (empty)
        matched

I have attached console output from the offending build.

My actual command line is:

.\b2 -j8 toolset=msvc-14.1 --build-type=minimal --without-mpi --without-python address-model=32 link=shared threading=multi runtime-link=shared windows-api=desktop stage

Thanks in advance!