Reference extension is weird/surprising and unnecessary, let's not do that.

Found by Chris Wailes

llvm-svn: 189859
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 8453a47..4fc54bd 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -10236,7 +10236,7 @@
     computeNRVO(Body, getCurBlock());
   
   BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy);
-  const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy();
+  AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
   PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result);
 
   // If the block isn't obviously global, i.e. it captures anything at