-Wc++98-compat warnings for the lexer.

This also adds a -Wc++98-compat-pedantic for warning on constructs which would
be diagnosed by -std=c++98 -pedantic (that is, it warns even on C++11 features
which we enable by default, with no warning, in C++98 mode).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142034 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 28 insertions, 8 deletions

diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index 802024f79b..a98d889dbc 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -1373,6 +1373,12 @@ void Lexer::LexStringLiteral(Token &Result, const char *CurPtr,
                              tok::TokenKind Kind) {
   const char *NulCharacter = 0; // Does this string contain the \0 character?
 
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf8_string_literal ||
+       Kind == tok::utf16_string_literal ||
+       Kind == tok::utf32_string_literal))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
   char C = getAndAdvanceChar(CurPtr, Result);
   while (C != '"') {
     // Skip escaped characters.  Escaped newlines will already be processed by
@@ -1419,6 +1425,9 @@ void Lexer::LexRawStringLiteral(Token &Result, const char *CurPtr,
   //  any transformations performed in phases 1 and 2 (trigraphs,
   //  universal-character-names, and line splicing) are reverted.
 
+  if (!isLexingRawMode())
+    Diag(BufferPtr, diag::warn_cxx98_compat_raw_string_literal);
+
   unsigned PrefixLen = 0;
 
   while (PrefixLen != 16 && isRawStringDelimBody(CurPtr[PrefixLen]))
@@ -1523,6 +1532,10 @@ void Lexer::LexCharConstant(Token &Result, const char *CurPtr,
                             tok::TokenKind Kind) {
   const char *NulCharacter = 0; // Does this character contain the \0 character?
 
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf16_char_constant || Kind == tok::utf32_char_constant))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
   char C = getAndAdvanceChar(CurPtr, Result);
   if (C == '\'') {
     if (!isLexingRawMode() && !Features.AsmPreprocessor)
@@ -2799,6 +2812,8 @@ LexNextToken:
         char After = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
         if (After != ':' && After != '>') {
           Kind = tok::less;
+          if (!isLexingRawMode())
+            Diag(BufferPtr, diag::warn_cxx98_compat_less_colon_colon);
           break;
         }
       }
diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index 482dd77e7e..de50c750e4 100644
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -777,6 +777,8 @@ void Preprocessor::HandleLineDirective(Token &Tok) {
     LineLimit = 2147483648U;
   if (LineNo >= LineLimit)
     Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit;
+  else if (Features.CPlusPlus0x && LineNo >= 32768U)
+    Diag(DigitTok, diag::warn_cxx98_compat_pp_line_too_big);
 
   int FilenameID = -1;
   Token StrTok;
@@ -1367,8 +1369,10 @@ bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) {
       Diag(Tok, diag::err_pp_expected_ident_in_arg_list);
       return true;
     case tok::ellipsis:  // #define X(... -> C99 varargs
-      if (!Features.C99 && !Features.CPlusPlus0x)
-        Diag(Tok, diag::ext_variadic_macro);
+      if (!Features.C99)
+        Diag(Tok, Features.CPlusPlus0x ? 
+             diag::warn_cxx98_compat_variadic_macro :
+             diag::ext_variadic_macro);
 
       // Lex the token after the identifier.
       LexUnexpandedToken(Tok);
diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
index 84156d59b9..20f624a0bb 100644
--- a/lib/Lex/PPExpressions.cpp
+++ b/lib/Lex/PPExpressions.cpp
@@ -216,9 +216,9 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     assert(Literal.isIntegerLiteral() && "Unknown ppnumber");
 
     // long long is a C99 feature.
-    if (!PP.getLangOptions().C99 && !PP.getLangOptions().CPlusPlus0x
-        && Literal.isLongLong)
-      PP.Diag(PeekTok, diag::ext_longlong);
+    if (!PP.getLangOptions().C99 && Literal.isLongLong)
+      PP.Diag(PeekTok, PP.getLangOptions().CPlusPlus0x ?
+              diag::warn_cxx98_compat_longlong : diag::ext_longlong);
 
     // Parse the integer literal into Result.
     if (Literal.GetIntegerValue(Result.Val)) {
@@ -778,4 +778,3 @@ EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro) {
   DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective;
   return ResVal.Val != 0;
 }
-
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 9b20605124..e10c95c75f 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -421,8 +421,10 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
 
     // Empty arguments are standard in C99 and C++0x, and are supported as an extension in
     // other modes.
-    if (ArgTokens.size() == ArgTokenStart && !Features.C99 && !Features.CPlusPlus0x)
-      Diag(Tok, diag::ext_empty_fnmacro_arg);
+    if (ArgTokens.size() == ArgTokenStart && !Features.C99)
+      Diag(Tok, Features.CPlusPlus0x ?
+           diag::warn_cxx98_compat_empty_fnmacro_arg :
+           diag::ext_empty_fnmacro_arg);
 
     // Add a marker EOF token to the end of the token list for this argument.
     Token EOFTok;