diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index 012189a..61bcef8 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -2550,7 +2550,7 @@
     return true;
   }
   
-  if (PP->isRecordingPreamble() && !PP->isInMainFile()) {
+  if (PP->isRecordingPreamble() && PP->isInPrimaryFile()) {
     PP->setRecordedPreambleConditionalStack(ConditionalStack);
     ConditionalStack.clear();
   }