3 files changed, 15 insertions, 0 deletions
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index 6cd960be20d..421d69d2430 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -9,6 +9,7 @@
 
 #include "clang/Frontend/FrontendActions.h"
 #include "clang/AST/ASTConsumer.h"
+#include "clang/Lex/Pragma.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Parse/Parser.h"
 #include "clang/Basic/FileManager.h"
@@ -223,6 +224,9 @@ void ParseOnlyAction::ExecuteAction() {
 void PreprocessOnlyAction::ExecuteAction() {
   Preprocessor &PP = getCompilerInstance().getPreprocessor();
 
+  // Ignore unknown pragmas.
+  PP.AddPragmaHandler(0, new EmptyPragmaHandler());
+
   Token Tok;
   // Start parsing the specified input file.
   PP.EnterMainSourceFile();
diff --git a/clang/lib/Frontend/PrintPreprocessedOutput.cpp b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
index b6c18b77316..e89c425f470 100644
--- a/clang/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -454,6 +454,9 @@ static int MacroIDCompare(const void* a, const void* b) {
 }
 
 static void DoPrintMacros(Preprocessor &PP, llvm::raw_ostream *OS) {
+  // Ignore unknown pragmas.
+  PP.AddPragmaHandler(0, new EmptyPragmaHandler());
+
   // -dM mode just scans and ignores all tokens in the files, then dumps out
   // the macro table at the end.
   PP.EnterMainSourceFile();
diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index 92332a00686..58a632618fd 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -27,6 +27,14 @@ PragmaHandler::~PragmaHandler() {
 }
 
 //===----------------------------------------------------------------------===//
+// EmptyPragmaHandler Implementation.
+//===----------------------------------------------------------------------===//
+
+EmptyPragmaHandler::EmptyPragmaHandler() : PragmaHandler(0) {}
+
+void EmptyPragmaHandler::HandlePragma(Preprocessor &PP, Token &FirstToken) {}
+
+//===----------------------------------------------------------------------===//
 // PragmaNamespace Implementation.
 //===----------------------------------------------------------------------===//