[boost] autolink should not require MSC language extensions

Recently I puzzled why autolink did not work for some programs. After some stumbling about, I realised that this was because _MSC_EXTENSIONS is a required definition (as well as MSVC). I can't see why this should be - autolink works perfectly well regardless of the compiler setting chosen. (But I can see why most people will not see this - because MS require the language extensions). But I suggest that in autolink.hpp #if (defined(BOOST_MSVC) && defined(_MSC_EXTENSIONS)) can helpfully be replaced by #if (defined(BOOST_MSVC)) for those whose preferences are for strictness'. Paul Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539 561830 +44 7714 330204 mailto: pbristow@hetp.u-net.com