improve comment.
llvm-svn: 48083
diff --git a/clang/Lex/PPLexerChange.cpp b/clang/Lex/PPLexerChange.cpp
index ed4e1eb..c5998c9 100644
--- a/clang/Lex/PPLexerChange.cpp
+++ b/clang/Lex/PPLexerChange.cpp
@@ -29,7 +29,7 @@
//===----------------------------------------------------------------------===//
/// isInPrimaryFile - Return true if we're in the top-level file, not in a
-/// #include.
+/// #include. This looks through macro expansions and active _Pragma lexers.
bool Preprocessor::isInPrimaryFile() const {
if (CurLexer && !CurLexer->Is_PragmaLexer)
return IncludeMacroStack.empty();