Lexer: Add extremely limited support for -traditional-cpp, ignoring BCPL

comments.

llvm-svn: 127910

2 files changed, 8 insertions, 3 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 31fcee2de88..9d9c99611cf 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -574,6 +574,8 @@ static void LangOptsToArgs(const LangOptions &Opts,
     Res.push_back("-fcxx-exceptions");
   if (Opts.SjLjExceptions)
     Res.push_back("-fsjlj-exceptions");
+  if (Opts.TraditionalCPP)
+    Res.push_back("-traditional-cpp");
   if (!Opts.RTTI)
     Res.push_back("-fno-rtti");
   if (Opts.MSBitfields)
@@ -1442,6 +1444,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.ObjCExceptions = Args.hasArg(OPT_fobjc_exceptions);
   Opts.CXXExceptions = Args.hasArg(OPT_fcxx_exceptions);
   Opts.SjLjExceptions = Args.hasArg(OPT_fsjlj_exceptions);
+  Opts.TraditionalCPP = Args.hasArg(OPT_traditional_cpp);
 
   Opts.RTTI = !Args.hasArg(OPT_fno_rtti);
   Opts.Blocks = Args.hasArg(OPT_fblocks);
diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index b511421ee77..6f3d611fb07 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -2091,7 +2091,7 @@ LexNextToken:
     // If the next token is obviously a // or /* */ comment, skip it efficiently
     // too (without going through the big switch stmt).
     if (CurPtr[0] == '/' && CurPtr[1] == '/' && !inKeepCommentMode() &&
-        Features.BCPLComment) {
+        Features.BCPLComment && !Features.TraditionalCPP) {
       if (SkipBCPLComment(Result, CurPtr+2))
         return; // There is a token to return.
       goto SkipIgnoredUnits;
@@ -2280,8 +2280,10 @@ LexNextToken:
       // this as "foo / bar" and langauges with BCPL comments would lex it as
       // "foo".  Check to see if the character after the second slash is a '*'.
       // If so, we will lex that as a "/" instead of the start of a comment.
-      if (Features.BCPLComment ||
-          getCharAndSize(CurPtr+SizeTmp, SizeTmp2) != '*') {
+      // However, we never do this in -traditional-cpp mode.
+      if ((Features.BCPLComment ||
+           getCharAndSize(CurPtr+SizeTmp, SizeTmp2) != '*') &&
+          !Features.TraditionalCPP) {
         if (SkipBCPLComment(Result, ConsumeChar(CurPtr, SizeTmp, Result)))
           return; // There is a token to return.