Clang: Inclusion gathering isn't working after the first time

Index: CIndexInclusionStack.cpp
===================================================================
--- CIndexInclusionStack.cpp	(revision 246452)
+++ CIndexInclusionStack.cpp	(working copy)
@@ -35,12 +35,28 @@
 
   SmallVector<CXSourceLocation, 10> InclusionStack;
   unsigned n =  SM.local_sloc_entry_size();
+  unsigned n2 = 0;
 
+  const SrcMgr::SLocEntry &(SourceManager::*Getter)(unsigned, bool*) const;
+  Getter = &SourceManager::getLocalSLocEntry;
+
+  for (unsigned i = 0 ; i < n ; ++i) {
+    bool Invalid = false;
+    const SrcMgr::SLocEntry &SL = (SM.*Getter)(i, &Invalid);
+
+    if (!SL.isFile() || Invalid)
+      continue;
+
+    const SrcMgr::FileInfo &FI = SL.getFile();
+    if (!FI.getContentCache()->OrigEntry)
+      continue;
+
+    ++n2;
+    }
   // In the case where all the SLocEntries are in an external source, traverse
   // those SLocEntries as well.  This is the case where we are looking
   // at the inclusion stack of an AST/PCH file.
-  const SrcMgr::SLocEntry &(SourceManager::*Getter)(unsigned, bool*) const;
-  if (n == 1) {
+  if (n2 == 1) {
     Getter = &SourceManager::getLoadedSLocEntry;
     n = SM.loaded_sloc_entry_size();
   } else