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git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@123370 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/StaticAnalyzer/PathSensitive/ExplodedGraph.h b/include/clang/StaticAnalyzer/PathSensitive/ExplodedGraph.h
index 3a7a991..853d3c5 100644
--- a/include/clang/StaticAnalyzer/PathSensitive/ExplodedGraph.h
+++ b/include/clang/StaticAnalyzer/PathSensitive/ExplodedGraph.h
@@ -47,6 +47,9 @@
 // on top of these classes.
 //===----------------------------------------------------------------------===//
 
+// ExplodedNode is not constified all over the engine because we need to add
+// successors to it at any time after creating it.
+
 class ExplodedNode : public llvm::FoldingSetNode {
   friend class ExplodedGraph;
   friend class CoreEngine;