File pr14831.patch of Package llvm

From 08c9add28c1a5b3c80b910d268a2f0a9f4d72995 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lubo=C5=A1=20Lu=C5=88=C3=A1k?= <l.lunak@suse.cz>
Date: Mon, 7 Jan 2013 12:37:28 +0100
Subject: [PATCH] do not warn about "unknown" pragmas in -frewrite-includes
 (pr#14831)

---
 lib/Rewrite/Frontend/InclusionRewriter.cpp |    8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/Rewrite/Frontend/InclusionRewriter.cpp b/lib/Rewrite/Frontend/InclusionRewriter.cpp
index 9d1bec9..dad15fa 100644
--- tools/clang/lib/Rewrite/Frontend/InclusionRewriter.cpp
+++ tools/clang/lib/Rewrite/Frontend/InclusionRewriter.cpp
@@ -13,6 +13,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Rewrite/Frontend/Rewriters.h"
+#include "clang/Lex/Pragma.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Frontend/PreprocessorOutputOptions.h"
@@ -344,6 +345,13 @@ void clang::RewriteIncludesInInput(Preprocessor &PP, raw_ostream *OS,
   InclusionRewriter *Rewrite = new InclusionRewriter(PP, *OS,
                                                      Opts.ShowLineMarkers);
   PP.addPPCallbacks(Rewrite);
+  // Ignore all pragmas, otherwise there will be warnings about unknown pragmas
+  // (because there's nothing to handle them).
+  PP.AddPragmaHandler(new EmptyPragmaHandler());
+  // Ignore also all pragma in all namespaces created
+  // in Preprocessor::RegisterBuiltinPragmas().
+  PP.AddPragmaHandler("GCC",new EmptyPragmaHandler());
+  PP.AddPragmaHandler("clang",new EmptyPragmaHandler());
 
   // First let the preprocessor process the entire file and call callbacks.
   // Callbacks will record which #include's were actually performed.
-- 
1.7.10.4