* 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