From 04ebde017f768c87895209e0dee9074ed145a0f3 Mon Sep 17 00:00:00 2001
From: Daniel Dunbar <daniel@zuster.org>
Date: Wed, 8 Sep 2010 18:19:55 +0000
Subject: [PATCH] Frontend/-H: Add comment on why I used a temporary string
 here.

llvm-svn: 113379
---
 clang/lib/Frontend/PrintPreprocessedOutput.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/clang/lib/Frontend/PrintPreprocessedOutput.cpp b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
index cfaf8a23b118..5ae02f97bd4b 100644
--- a/clang/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -263,6 +263,7 @@ void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,
   // predefines buffer.
   if (DumpHeaderIncludes && HasProcessedPredefines &&
       Reason == PPCallbacks::EnterFile) {
+    // Write to a temporary string to avoid unnecessary flushing on errs().
     llvm::SmallString<256> Msg;
     llvm::raw_svector_ostream OS(Msg);
     for (unsigned i = 0; i != CurrentIncludeDepth; ++i)