diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -3645,13 +3645,13 @@
     // file.
     SmallVector<const IdentifierInfo *, 128> IIs;
     for (const auto &ID : PP.getIdentifierTable())
-      IIs.push_back(ID.second);
-    // Sort the identifiers lexicographically before getting them references so
+      if (Trait.isInterestingNonMacroIdentifier(ID.second))
+        IIs.push_back(ID.second);
+    // Sort the identifiers lexicographically before getting the references so
     // that their order is stable.
     llvm::sort(IIs, llvm::deref<std::less<>>());
     for (const IdentifierInfo *II : IIs)
-      if (Trait.isInterestingNonMacroIdentifier(II))
-        getIdentifierRef(II);
+      getIdentifierRef(II);
 
     // Create the on-disk hash table representation. We only store offsets
     // for identifiers that appear here for the first time.