Revert r147664; it's breaking clang regression tests.

llvm-svn: 147681
diff --git a/clang/lib/CodeGen/CGExprAgg.cpp b/clang/lib/CodeGen/CGExprAgg.cpp
index 8f0e584..47984af 100644
--- a/clang/lib/CodeGen/CGExprAgg.cpp
+++ b/clang/lib/CodeGen/CGExprAgg.cpp
@@ -469,7 +469,7 @@
   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
 
   // Bind the common expression if necessary.
-  CodeGenFunction::OpaqueValueMapping(CGF, E);
+  CodeGenFunction::OpaqueValueMapping binding(CGF, E);
 
   CodeGenFunction::ConditionalEvaluation eval(CGF);
   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);