5 files changed, 23 insertions, 7 deletions
diff --git a/clang/lib/Basic/LangOptions.cpp b/clang/lib/Basic/LangOptions.cpp
index 61072b7..e5adc03 100644
--- a/clang/lib/Basic/LangOptions.cpp
+++ b/clang/lib/Basic/LangOptions.cpp
@@ -125,6 +125,7 @@ void LangOptions::setLangDefaults(LangOptions &Opts, Language Lang,
   Opts.HexFloats = Std.hasHexFloats();
   Opts.WChar = Std.isCPlusPlus();
   Opts.Digraphs = Std.hasDigraphs();
+  Opts.RawStringLiterals = Std.hasRawStringLiterals();
 
   Opts.HLSL = Lang == Language::HLSL;
   if (Opts.HLSL && Opts.IncludeDefaultHeader)
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 6ba0d56..edb3c20 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -6519,6 +6519,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   Args.AddLastArg(CmdArgs, options::OPT_fheinous_gnu_extensions);
   Args.AddLastArg(CmdArgs, options::OPT_fdigraphs, options::OPT_fno_digraphs);
   Args.AddLastArg(CmdArgs, options::OPT_fzero_call_used_regs_EQ);
+  Args.AddLastArg(CmdArgs, options::OPT_fraw_string_literals,
+                  options::OPT_fno_raw_string_literals);
 
   if (Args.hasFlag(options::OPT_femulated_tls, options::OPT_fno_emulated_tls,
                    Triple.hasDefaultEmulatedTLS()))
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index f42e28b..0082c15 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -610,6 +610,19 @@ static bool FixupInvocation(CompilerInvocation &Invocation,
     LangOpts.NewAlignOverride = 0;
   }
 
+  // The -f[no-]raw-string-literals option is only valid in C and in C++
+  // standards before C++11.
+  if (LangOpts.CPlusPlus11) {
+    if (Args.hasArg(OPT_fraw_string_literals, OPT_fno_raw_string_literals)) {
+      Args.claimAllArgs(OPT_fraw_string_literals, OPT_fno_raw_string_literals);
+      Diags.Report(diag::warn_drv_fraw_string_literals_in_cxx11)
+          << bool(LangOpts.RawStringLiterals);
+    }
+
+    // Do not allow disabling raw string literals in C++11 or later.
+    LangOpts.RawStringLiterals = true;
+  }
+
   // Prevent the user from specifying both -fsycl-is-device and -fsycl-is-host.
   if (LangOpts.SYCLIsDevice && LangOpts.SYCLIsHost)
     Diags.Report(diag::err_drv_argument_not_allowed_with) << "-fsycl-is-device"
diff --git a/clang/lib/Lex/DependencyDirectivesScanner.cpp b/clang/lib/Lex/DependencyDirectivesScanner.cpp
index 0971daa..57652be 100644
--- a/clang/lib/Lex/DependencyDirectivesScanner.cpp
+++ b/clang/lib/Lex/DependencyDirectivesScanner.cpp
@@ -73,8 +73,8 @@ struct Scanner {
     // Set the lexer to use 'tok::at' for '@', instead of 'tok::unknown'.
     LangOpts.ObjC = true;
     LangOpts.LineComment = true;
-    // FIXME: we do not enable C11 or C++11, so we are missing u/u8/U"" and
-    // R"()" literals.
+    LangOpts.RawStringLiterals = true;
+    // FIXME: we do not enable C11 or C++11, so we are missing u/u8/U"".
     return LangOpts;
   }
 
diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index e59c780..ef1e1f4 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -3876,7 +3876,7 @@ LexStart:
                                tok::utf16_char_constant);
 
       // UTF-16 raw string literal
-      if (Char == 'R' && LangOpts.CPlusPlus11 &&
+      if (Char == 'R' && LangOpts.RawStringLiterals &&
           getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
         return LexRawStringLiteral(Result,
                                ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
@@ -3898,7 +3898,7 @@ LexStart:
                                   SizeTmp2, Result),
               tok::utf8_char_constant);
 
-        if (Char2 == 'R' && LangOpts.CPlusPlus11) {
+        if (Char2 == 'R' && LangOpts.RawStringLiterals) {
           unsigned SizeTmp3;
           char Char3 = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
           // UTF-8 raw string literal
@@ -3934,7 +3934,7 @@ LexStart:
                                tok::utf32_char_constant);
 
       // UTF-32 raw string literal
-      if (Char == 'R' && LangOpts.CPlusPlus11 &&
+      if (Char == 'R' && LangOpts.RawStringLiterals &&
           getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
         return LexRawStringLiteral(Result,
                                ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
@@ -3949,7 +3949,7 @@ LexStart:
     // Notify MIOpt that we read a non-whitespace/non-comment token.
     MIOpt.ReadToken();
 
-    if (LangOpts.CPlusPlus11) {
+    if (LangOpts.RawStringLiterals) {
       Char = getCharAndSize(CurPtr, SizeTmp);
 
       if (Char == '"')
@@ -3972,7 +3972,7 @@ LexStart:
                               tok::wide_string_literal);
 
     // Wide raw string literal.
-    if (LangOpts.CPlusPlus11 && Char == 'R' &&
+    if (LangOpts.RawStringLiterals && Char == 'R' &&
         getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
       return LexRawStringLiteral(Result,
                                ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),