[c++2a] Treat 'concept' and 'requires' as keywords, add compat warning for C++17 and before.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@310803 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/DiagnosticGroups.td

@@ -224,6 +224,8 @@ def CXX1zCompat : DiagGroup<"c++1z-compat", [DeprecatedRegister,
                                              DeprecatedIncrementBool,
                                              CXX1zCompatMangling]>;
 
+def CXX2aCompat : DiagGroup<"c++2a-compat">;
+
 def ExitTimeDestructors : DiagGroup<"exit-time-destructors">;
 def FlexibleArrayExtensions : DiagGroup<"flexible-array-extensions">;
 def FourByteMultiChar : DiagGroup<"four-char-constants">;

include/clang/Basic/DiagnosticLexKinds.td

@@ -71,6 +71,8 @@ def ext_token_used : Extension<"extension used">,
 
 def warn_cxx11_keyword : Warning<"'%0' is a keyword in C++11">,
   InGroup<CXX11Compat>, DefaultIgnore;
+def warn_cxx2a_keyword : Warning<"'%0' is a keyword in C++2a">,
+  InGroup<CXX2aCompat>, DefaultIgnore;
 
 def ext_unterminated_char_or_string : ExtWarn<
   "missing terminating %select{'|'\"'}0 character">, InGroup<InvalidPPToken>;

include/clang/Basic/TokenKinds.def

@@ -27,8 +27,11 @@
 #ifndef CXX11_KEYWORD
 #define CXX11_KEYWORD(X,Y) KEYWORD(X,KEYCXX11|(Y))
 #endif
+#ifndef CXX2A_KEYWORD
+#define CXX2A_KEYWORD(X,Y) KEYWORD(X,KEYCXX2A|(Y))
+#endif
 #ifndef CONCEPTS_KEYWORD
-#define CONCEPTS_KEYWORD(X) KEYWORD(X,KEYCONCEPTS)
+#define CONCEPTS_KEYWORD(X) CXX2A_KEYWORD(X,KEYCONCEPTS)
 #endif
 #ifndef MODULES_KEYWORD
 #define MODULES_KEYWORD(X) KEYWORD(X,KEYMODULES)
@@ -236,6 +239,7 @@ PUNCTUATOR(caretcaret,            "^^")
 //              implementation namespace
 //   KEYNOCXX - This is a keyword in every non-C++ dialect.
 //   KEYCXX11 - This is a C++ keyword introduced to C++ in C++11
+//   KEYCXX2A - This is a C++ keyword introduced to C++ in C++2a
 //   KEYCONCEPTS - This is a keyword if the C++ extensions for concepts
 //                 are enabled.
 //   KEYMODULES - This is a keyword if the C++ extensions for modules
@@ -362,7 +366,7 @@ CXX11_KEYWORD(nullptr               , 0)
 CXX11_KEYWORD(static_assert         , 0)
 CXX11_KEYWORD(thread_local          , 0)
 
-// C++ concepts TS keywords
+// C++2a / concepts TS keywords
 CONCEPTS_KEYWORD(concept)
 CONCEPTS_KEYWORD(requires)
 
@@ -810,6 +814,7 @@ ANNOTATION(module_end)
 #undef TYPE_TRAIT_1
 #undef TYPE_TRAIT
 #undef CONCEPTS_KEYWORD
+#undef CXX2A_KEYWORD
 #undef CXX11_KEYWORD
 #undef KEYWORD
 #undef PUNCTUATOR

lib/Basic/IdentifierTable.cpp

@@ -114,7 +114,9 @@ namespace {
     KEYZVECTOR  = 0x40000,
     KEYCOROUTINES = 0x80000,
     KEYMODULES = 0x100000,
-    KEYALL = (0x1fffff & ~KEYNOMS18 &
+    KEYCXX2A = 0x200000,
+    KEYALLCXX = KEYCXX | KEYCXX11 | KEYCXX2A,
+    KEYALL = (0x3fffff & ~KEYNOMS18 &
               ~KEYNOOPENCL) // KEYNOMS18 and KEYNOOPENCL are used to exclude.
   };
 
@@ -134,6 +136,7 @@ static KeywordStatus getKeywordStatus(const LangOptions &LangOpts,
   if (Flags == KEYALL) return KS_Enabled;
   if (LangOpts.CPlusPlus && (Flags & KEYCXX)) return KS_Enabled;
   if (LangOpts.CPlusPlus11 && (Flags & KEYCXX11)) return KS_Enabled;
+  if (LangOpts.CPlusPlus2a && (Flags & KEYCXX2A)) return KS_Enabled;
   if (LangOpts.C99 && (Flags & KEYC99)) return KS_Enabled;
   if (LangOpts.GNUKeywords && (Flags & KEYGNU)) return KS_Extension;
   if (LangOpts.MicrosoftExt && (Flags & KEYMS)) return KS_Extension;
@@ -152,7 +155,7 @@ static KeywordStatus getKeywordStatus(const LangOptions &LangOpts,
   if (LangOpts.ConceptsTS && (Flags & KEYCONCEPTS)) return KS_Enabled;
   if (LangOpts.CoroutinesTS && (Flags & KEYCOROUTINES)) return KS_Enabled;
   if (LangOpts.ModulesTS && (Flags & KEYMODULES)) return KS_Enabled;
-  if (LangOpts.CPlusPlus && (Flags & KEYCXX11)) return KS_Future;
+  if (LangOpts.CPlusPlus && (Flags & KEYALLCXX)) return KS_Future;
   return KS_Disabled;
 }
 
@@ -264,6 +267,7 @@ bool IdentifierInfo::isCPlusPlusKeyword(const LangOptions &LangOpts) const {
   LangOptions LangOptsNoCPP = LangOpts;
   LangOptsNoCPP.CPlusPlus = false;
   LangOptsNoCPP.CPlusPlus11 = false;
+  LangOptsNoCPP.CPlusPlus2a = false;
   return !isKeyword(LangOptsNoCPP);
 }
 

lib/Lex/Preprocessor.cpp

@@ -630,6 +630,8 @@ static diag::kind getFutureCompatDiagKind(const IdentifierInfo &II,
     return llvm::StringSwitch<diag::kind>(II.getName())
 #define CXX11_KEYWORD(NAME, FLAGS)                                             \
         .Case(#NAME, diag::warn_cxx11_keyword)
+#define CXX2A_KEYWORD(NAME, FLAGS)                                             \
+        .Case(#NAME, diag::warn_cxx2a_keyword)
 #include "clang/Basic/TokenKinds.def"
         ;
 

test/Lexer/keywords_test.cpp

@@ -1,6 +1,7 @@
 // RUN: %clang_cc1 -std=c++03 -fsyntax-only %s
 // RUN: %clang_cc1 -std=c++11 -DCXX11 -fsyntax-only %s
 // RUN: %clang_cc1 -std=c++14 -fconcepts-ts -DCXX11 -DCONCEPTS -fsyntax-only %s
+// RUN: %clang_cc1 -std=c++2a -DCXX11 -DCXX2A -fsyntax-only %s
 // RUN: %clang_cc1 -std=c++03 -fdeclspec -DDECLSPEC -fsyntax-only %s
 // RUN: %clang_cc1 -std=c++03 -fms-extensions -DDECLSPEC -fsyntax-only %s
 // RUN: %clang_cc1 -std=c++03 -fborland-extensions -DDECLSPEC -fsyntax-only %s
@@ -19,7 +20,7 @@
 #define NOT_KEYWORD(NAME) _Static_assert(__is_identifier(NAME), #NAME)
 #define IS_TYPE(NAME) void is_##NAME##_type() { int f(NAME); }
 
-#ifdef CONCEPTS
+#if defined(CONCEPTS) || defined(CXX2A)
 #define CONCEPTS_KEYWORD(NAME)  IS_KEYWORD(NAME)
 #else
 #define CONCEPTS_KEYWORD(NAME)  NOT_KEYWORD(NAME)