boostorg/config — pull request #40 by igaztanaga (2014-09-26 09:05:42+00:00)
Title: Make std lib detection a bit more lightweight

...on environments where cstddef is enough to detect BOOST_STDLIB_CONFIG. Backup to (which has become heavier in C++11, has it needs traits for move_if_noexcept..) if std lib has not been detected.

The patch splits the detection in an auxiliary header and includes it twice in case cstddef is not enough.