* libsupc++/unwind-cxx.h: Include sys/sdt.h if detected. (PROBE2): New macro. * libsupc++/eh_throw.cc (__cxa_throw, __cxa_rethrow): Add probe. * libsupc++/eh_catch.cc (__cxa_begin_catch): Add probe. * configure.ac: Check for sys/sdt.h. * configure, config.h.in: Rebuild. From-SVN: r196674