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git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60516 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/RegionStore.cpp b/lib/Analysis/RegionStore.cpp
index 9753b91..006b613 100644
--- a/lib/Analysis/RegionStore.cpp
+++ b/lib/Analysis/RegionStore.cpp
@@ -148,7 +148,13 @@
   Store BindStructToVal(Store store, const TypedRegion* BaseR, SVal V);
   Store BindStructToSymVal(Store store, const TypedRegion* BaseR);
 
+  /// Retrieve the values in a struct and return a CompoundVal, used when doing
+  /// struct copy: 
+  /// struct s x, y; 
+  /// x = y;
+  /// y's value is retrieved by this method.
   SVal RetrieveStruct(Store store, const TypedRegion* R);
+
   Store BindStruct(Store store, const TypedRegion* R, SVal V);
 
   // Utility methods.