diff --git a/include/clang-c/Index.h b/include/clang-c/Index.h
index 858b2ce..b9197b8 100644
--- a/include/clang-c/Index.h
+++ b/include/clang-c/Index.h
@@ -840,7 +840,17 @@
    * a large amount of storage to due preprocessor metaprogramming. Moreover,
    * its fairly rare that this information is useful for libclang clients.
    */
-  CXTranslationUnit_NestedMacroInstantiations = 0x40
+  CXTranslationUnit_NestedMacroExpansions = 0x40,
+
+  /**
+   * \brief Legacy name to indicate that the "detailed" preprocessing record,
+   * if requested, should contain nested macro instantiations.
+   *
+   * \see CXTranslationUnit_NestedMacroExpansions for the current name for this
+   * value, and its semantics. This is just an alias.
+   */
+  CXTranslationUnit_NestedMacroInstantiations =
+    CXTranslationUnit_NestedMacroExpansions
 };
 
 /**
diff --git a/include/clang/Frontend/ASTUnit.h b/include/clang/Frontend/ASTUnit.h
index b475880..58a60a1 100644
--- a/include/clang/Frontend/ASTUnit.h
+++ b/include/clang/Frontend/ASTUnit.h
@@ -249,9 +249,9 @@
   /// \brief Whether we should be caching code-completion results.
   bool ShouldCacheCodeCompletionResults;
   
-  /// \brief Whether we want to include nested macro instantiations in the
+  /// \brief Whether we want to include nested macro expansions in the
   /// detailed preprocessing record.
-  bool NestedMacroInstantiations;
+  bool NestedMacroExpansions;
   
   static void ConfigureDiags(llvm::IntrusiveRefCntPtr<Diagnostic> &Diags,
                              const char **ArgBegin, const char **ArgEnd,
@@ -612,7 +612,7 @@
                                              bool PrecompilePreamble = false,
                                           bool CompleteTranslationUnit = true,
                                        bool CacheCodeCompletionResults = false,
-                                       bool NestedMacroInstantiations = true);
+                                       bool NestedMacroExpansions = true);
 
   /// LoadFromCommandLine - Create an ASTUnit from a vector of command line
   /// arguments, which must specify exactly one source file.
@@ -642,7 +642,7 @@
                                       bool CacheCodeCompletionResults = false,
                                       bool CXXPrecompilePreamble = false,
                                       bool CXXChainedPCH = false,
-                                      bool NestedMacroInstantiations = true);
+                                      bool NestedMacroExpansions = true);
   
   /// \brief Reparse the source files using the same command-line options that
   /// were originally used to produce this translation unit.
diff --git a/include/clang/Frontend/PreprocessorOptions.h b/include/clang/Frontend/PreprocessorOptions.h
index 5ab4ed5..8856805 100644
--- a/include/clang/Frontend/PreprocessorOptions.h
+++ b/include/clang/Frontend/PreprocessorOptions.h
@@ -51,8 +51,8 @@
                                /// instantiations.
   
   /// \brief Whether the detailed preprocessing record includes nested macro 
-  /// instantiations.
-  unsigned DetailedRecordIncludesNestedMacroInstantiations : 1;
+  /// expansions.
+  unsigned DetailedRecordIncludesNestedMacroExpansions : 1;
   
   /// The implicit PCH included at the start of the translation unit, or empty.
   std::string ImplicitPCHInclude;
@@ -154,7 +154,7 @@
   
 public:
   PreprocessorOptions() : UsePredefines(true), DetailedRecord(false),
-                          DetailedRecordIncludesNestedMacroInstantiations(true),
+                          DetailedRecordIncludesNestedMacroExpansions(true),
                           DisablePCHValidation(false), DisableStatCache(false),
                           DumpDeserializedPCHDecls(false),
                           PrecompiledPreambleBytes(0, true),
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index ad47645..5b0a52c 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -102,7 +102,7 @@
     ConcurrencyCheckValue(CheckUnlocked), 
     PreambleRebuildCounter(0), SavedMainFileBuffer(0), PreambleBuffer(0),
     ShouldCacheCodeCompletionResults(false),
-    NestedMacroInstantiations(true),
+    NestedMacroExpansions(true),
     CompletionCacheTopLevelHashValue(0),
     PreambleTopLevelHashValue(0),
     CurrentTopLevelHashValue(0),
@@ -934,8 +934,8 @@
   // If the main file has been overridden due to the use of a preamble,
   // make that override happen and introduce the preamble.
   PreprocessorOptions &PreprocessorOpts = Clang->getPreprocessorOpts();
-  PreprocessorOpts.DetailedRecordIncludesNestedMacroInstantiations
-    = NestedMacroInstantiations;
+  PreprocessorOpts.DetailedRecordIncludesNestedMacroExpansions
+    = NestedMacroExpansions;
   std::string PriorImplicitPCHInclude;
   if (OverrideMainBuffer) {
     PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
@@ -1725,7 +1725,7 @@
                                              bool PrecompilePreamble,
                                              bool CompleteTranslationUnit,
                                              bool CacheCodeCompletionResults,
-                                             bool NestedMacroInstantiations) {  
+                                             bool NestedMacroExpansions) {  
   // Create the AST unit.
   llvm::OwningPtr<ASTUnit> AST;
   AST.reset(new ASTUnit(false));
@@ -1736,7 +1736,7 @@
   AST->CompleteTranslationUnit = CompleteTranslationUnit;
   AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
   AST->Invocation = CI;
-  AST->NestedMacroInstantiations = NestedMacroInstantiations;
+  AST->NestedMacroExpansions = NestedMacroExpansions;
   
   // Recover resources if we crash before exiting this method.
   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
@@ -1762,7 +1762,7 @@
                                       bool CacheCodeCompletionResults,
                                       bool CXXPrecompilePreamble,
                                       bool CXXChainedPCH,
-                                      bool NestedMacroInstantiations) {
+                                      bool NestedMacroExpansions) {
   if (!Diags.getPtr()) {
     // No diagnostics engine was provided, so create our own diagnostics object
     // with the default options.
@@ -1829,7 +1829,7 @@
   AST->NumStoredDiagnosticsInPreamble = StoredDiagnostics.size();
   AST->StoredDiagnostics.swap(StoredDiagnostics);
   AST->Invocation = CI;
-  AST->NestedMacroInstantiations = NestedMacroInstantiations;
+  AST->NestedMacroExpansions = NestedMacroExpansions;
   
   // Recover resources if we crash before exiting this method.
   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index cb91c89..c58e3af 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -229,7 +229,7 @@
 
   if (PPOpts.DetailedRecord)
     PP->createPreprocessingRecord(
-                       PPOpts.DetailedRecordIncludesNestedMacroInstantiations);
+                       PPOpts.DetailedRecordIncludesNestedMacroExpansions);
   
   InitializePreprocessor(*PP, PPOpts, HSOpts, FEOpts);
 
diff --git a/tools/c-index-test/c-index-test.c b/tools/c-index-test/c-index-test.c
index e574b87..6e0aaac 100644
--- a/tools/c-index-test/c-index-test.c
+++ b/tools/c-index-test/c-index-test.c
@@ -38,7 +38,7 @@
   if (getenv("CINDEXTEST_COMPLETION_CACHING"))
     options |= CXTranslationUnit_CacheCompletionResults;
   if (getenv("CINDEXTEST_NESTED_MACROS"))
-    options |= CXTranslationUnit_NestedMacroInstantiations;
+    options |= CXTranslationUnit_NestedMacroExpansions;
   
   return options;
 }
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 02ef6f8..c78584a 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -2391,7 +2391,7 @@
                                           unsigned num_unsaved_files,
                                           struct CXUnsavedFile *unsaved_files) {
   unsigned Options = CXTranslationUnit_DetailedPreprocessingRecord |
-                     CXTranslationUnit_NestedMacroInstantiations;
+                     CXTranslationUnit_NestedMacroExpansions;
   return clang_parseTranslationUnit(CIdx, source_filename,
                                     command_line_args, num_command_line_args,
                                     unsaved_files, num_unsaved_files,
@@ -2496,12 +2496,12 @@
     Args->push_back(source_filename);
 
   // Do we need the detailed preprocessing record?
-  bool NestedMacroInstantiations = false;
+  bool NestedMacroExpansions = false;
   if (options & CXTranslationUnit_DetailedPreprocessingRecord) {
     Args->push_back("-Xclang");
     Args->push_back("-detailed-preprocessing-record");
-    NestedMacroInstantiations
-      = (options & CXTranslationUnit_NestedMacroInstantiations);
+    NestedMacroExpansions
+      = (options & CXTranslationUnit_NestedMacroExpansions);
   }
   
   unsigned NumErrors = Diags->getClient()->getNumErrors();
@@ -2521,7 +2521,7 @@
                                  CacheCodeCompetionResults,
                                  CXXPrecompilePreamble,
                                  CXXChainedPCH,
-                                 NestedMacroInstantiations));
+                                 NestedMacroExpansions));
 
   if (NumErrors != Diags->getClient()->getNumErrors()) {
     // Make sure to check that 'Unit' is non-NULL.