Merged revisions 61928 via svnmerge from

https://svn.boost.org/svn/boost/trunk

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  r61928 | eric_niebler | 2010-05-11 23:35:30 -0700 (Tue, 11 May 2010) | 1 line
  
  fix clang/cygwin bbv2 problem (with Doug's blessing)
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[SVN r62133]

tools/build

@@ -1 +1 @@
-Subproject commit 71957d2eaf730cc2211f7bae9e5976401e72be5f
+Subproject commit a407890ca2e7a52fdda5c3b94ca18ddff58ca65c