Don't record nested macro expansions in the preprocessing record,
it can only bring pain when dealing with preprocessor abuse (see: boost).

rdar://10898986

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151427 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 53c7634..924a843 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -2454,8 +2454,7 @@
                                           const char * const *command_line_args,
                                           unsigned num_unsaved_files,
                                           struct CXUnsavedFile *unsaved_files) {
-  unsigned Options = CXTranslationUnit_DetailedPreprocessingRecord |
-                     CXTranslationUnit_NestedMacroExpansions;
+  unsigned Options = CXTranslationUnit_DetailedPreprocessingRecord;
   return clang_parseTranslationUnit(CIdx, source_filename,
                                     command_line_args, num_command_line_args,
                                     unsaved_files, num_unsaved_files,
@@ -2557,12 +2556,9 @@
     Args->push_back(source_filename);
 
   // Do we need the detailed preprocessing record?
-  bool NestedMacroExpansions = false;
   if (options & CXTranslationUnit_DetailedPreprocessingRecord) {
     Args->push_back("-Xclang");
     Args->push_back("-detailed-preprocessing-record");
-    NestedMacroExpansions
-      = (options & CXTranslationUnit_NestedMacroExpansions);
   }
   
   unsigned NumErrors = Diags->getClient()->getNumErrors();
@@ -2579,8 +2575,7 @@
                                  /*RemappedFilesKeepOriginalName=*/true,
                                  PrecompilePreamble,
                                  TUKind,
-                                 CacheCodeCompetionResults,
-                                 NestedMacroExpansions));
+                                 CacheCodeCompetionResults));
 
   if (NumErrors != Diags->getClient()->getNumErrors()) {
     // Make sure to check that 'Unit' is non-NULL.