Hi, quite a number of headers in boost/config/compiler have bits like this: # error "Unknown compiler version - please run the configure tests and report the results" I think this cause more hard than good these days. If a new version of an otherwise perfectly conforming compiler is released, this error will be emitted when compiling Boost. So, users would have to manually hack the config headers and keep this change locally. And, it's likely that some users won't even bother -- especially given that the message say to run some configure tests, and where those configure tests are is not clear. And definitely, those tests have nothing to do with the 'configure' script at the top-level dir. So, the message is likely to totally confuse some users, and force other users to keep local modifications to boost. Can we either remove this check, or assume that unknown version of compiler is identical in behaviour to the last known one? Thanks, Volodya