commit 259c0cf27d0a88eecc90af1aa500f88f6108cb04
Author: Torvald Riegel <triegel@redhat.com>
Date:   Thu Jan 21 16:21:33 2016 +0100

    libitm: Disable testing transaction-safe exceptions on Darwin and AIX.
    
    	* testsuite/libitm.c++/libstdc++-safeexc.C: Not supported on darwin
    	or AIX.

diff --git a/libitm/testsuite/libitm.c++/libstdc++-safeexc.C b/libitm/testsuite/libitm.c++/libstdc++-safeexc.C
index 3e1655e..55ebd25 100644
--- a/libitm/testsuite/libitm.c++/libstdc++-safeexc.C
+++ b/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>