libitm: Disable testing transaction-safe exceptions on Darwin and AIX.

	* testsuite/libitm.c++/libstdc++-safeexc.C: Not supported on darwin
	or AIX.

From-SVN: r232693

libitm/ChangeLog

+2016-01-21  Torvald Riegel  <triegel@redhat.com>
+
+	* testsuite/libitm.c++/libstdc++-safeexc.C: Not supported on darwin
+	or AIX.
+
 2016-01-19  Richard Henderson  <rth@redhat.com>
 
 	PR bootstrap/69343

libitm/testsuite/libitm.c++/libstdc++-safeexc.C

@@ -2,7 +2,10 @@
 // are indeed that.  Thus, this also tests the transactional clones in
 // libstdc++ and libsupc++.
 
-// { dg-do run }
+// Not supported on Darwin nor AIX because those lack the support for
+// weak references to undefined functions that we need in libstdc++ to make
+// exceptions transaction-safe.
+// { dg-do run { target { ! { *-*-darwin* powerpc-ibm-aix* } } } }
 
 #include <iostream>
 #include <exception>