Add cc1 option -fconcepts-ts + feature test macro

[hubert.reinterpretcast]

Summary

This adds -fconcepts-ts as a cc1 option for enabling the
in-progress implementation of the Concepts TS. The recommended feature
test macro __cpp_experimental_concepts is set to 1 (as opposed to
201501) to indicate that the feature is enabled, but the
implementation is incomplete.

The link to the Concepts TS in cxx_status is updated to refer to the
PDTS (N4377). Additional changes related to __has_feature and
__has_extension are to follow in a later change.

[faisalv]

Committed as r237982.

http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20150518/129643.html

Richard - are you ok with us proceeding like this (for tiny innocuous
patches), until Hubert gets his access?

Thanks!

Faisal Vali

[hubert.reinterpretcast]

This was incorporated in r237982.

include/clang/Basic/LangOptions.def

 LANGOPT(CUDA              , 1, 0, "CUDA")
 LANGOPT(OpenMP            , 1, 0, "OpenMP support")
 LANGOPT(CUDAIsDevice      , 1, 0, "Compiling for CUDA device")
 LANGOPT(CUDAAllowHostCallsFromHostDevice, 1, 0, "Allow host device functions to call host functions")
 LANGOPT(CUDADisableTargetCallChecks, 1, 0, "Disable checks for call targets (host, device, etc.)")
 
 LANGOPT(AssumeSaneOperatorNew , 1, 1, "implicit __attribute__((malloc)) for C++'s new operators")
 LANGOPT(SizedDeallocation , 1, 0, "enable sized deallocation functions")
+LANGOPT(ConceptsTS , 1, 0, "enable C++ Extensions for Concepts")
 BENIGN_LANGOPT(ElideConstructors , 1, 1, "C++ copy constructor elision")
 BENIGN_LANGOPT(DumpRecordLayouts , 1, 0, "dumping the layout of IRgen'd records")
 BENIGN_LANGOPT(DumpRecordLayoutsSimple , 1, 0, "dumping the layout of IRgen'd records in a simple form")
 BENIGN_LANGOPT(DumpVTableLayouts , 1, 0, "dumping the layouts of emitted vtables")
 LANGOPT(NoConstantCFStrings , 1, 0, "no constant CoreFoundation strings")
 BENIGN_LANGOPT(InlineVisibilityHidden , 1, 0, "hidden default visibility for inline C++ methods")
 BENIGN_LANGOPT(ParseUnknownAnytype, 1, 0, "__unknown_anytype")
 BENIGN_LANGOPT(DebuggerSupport , 1, 0, "debugger support")

include/clang/Driver/CC1Options.td

HelpText<"Use the current working directory as the home directory of "
            "module maps specified by -fmodule-map-file=<FILE>">;
 def fmodule_feature : Separate<["-"], "fmodule-feature">,
   MetaVarName<"<feature>">,
   HelpText<"Enable <feature> in module map requires declarations">;
 def fmodules_local_submodule_visibility :
   Flag<["-"], "fmodules-local-submodule-visibility">,
   HelpText<"Enforce name visibility rules across submodules of the same "
            "top-level module.">;
+def fconcepts_ts : Flag<["-"], "fconcepts-ts">,
+  HelpText<"Enable C++ Extensions for Concepts.">;
 
 let Group = Action_Group in {
 
 def Eonly : Flag<["-"], "Eonly">,
   HelpText<"Just run preprocessor, no output (for timings)">;
 def dump_raw_tokens : Flag<["-"], "dump-raw-tokens">,
   HelpText<"Lex file in raw mode and dump raw tokens">;
 def analyze : Flag<["-"], "analyze">,

lib/Frontend/CompilerInvocation.cpp

#include "clang/Frontend/LangStandards.def"
   Opts.WChar = Opts.CPlusPlus && !Args.hasArg(OPT_fno_wchar);
   Opts.ShortWChar = Args.hasFlag(OPT_fshort_wchar, OPT_fno_short_wchar, false);
   Opts.ShortEnums = Args.hasArg(OPT_fshort_enums);
   Opts.Freestanding = Args.hasArg(OPT_ffreestanding);
   Opts.NoBuiltin = Args.hasArg(OPT_fno_builtin) || Opts.Freestanding;
   Opts.NoMathBuiltin = Args.hasArg(OPT_fno_math_builtin);
   Opts.AssumeSaneOperatorNew = !Args.hasArg(OPT_fno_assume_sane_operator_new);
   Opts.SizedDeallocation = Args.hasArg(OPT_fsized_deallocation);
+  Opts.ConceptsTS = Args.hasArg(OPT_fconcepts_ts);
   Opts.HeinousExtensions = Args.hasArg(OPT_fheinous_gnu_extensions);
   Opts.AccessControl = !Args.hasArg(OPT_fno_access_control);
   Opts.ElideConstructors = !Args.hasArg(OPT_fno_elide_constructors);
   Opts.MathErrno = !Opts.OpenCL && Args.hasArg(OPT_fmath_errno);
   Opts.InstantiationDepth =
       getLastArgIntValue(Args, OPT_ftemplate_depth, 256, Diags);
   Opts.ArrowDepth =
       getLastArgIntValue(Args, OPT_foperator_arrow_depth, 256, Diags);

lib/Frontend/InitPreprocessor.cpp

if (LangOpts.CPlusPlus14) {
     Builder.defineMacro("__cpp_generic_lambdas", "201304");
     Builder.defineMacro("__cpp_decltype_auto", "201304");
     Builder.defineMacro("__cpp_return_type_deduction", "201304");
     Builder.defineMacro("__cpp_aggregate_nsdmi", "201304");
     Builder.defineMacro("__cpp_variable_templates", "201304");
   }
   if (LangOpts.SizedDeallocation)
     Builder.defineMacro("__cpp_sized_deallocation", "201309");
+  if (LangOpts.ConceptsTS)
+    Builder.defineMacro("__cpp_experimental_concepts", "1");
 }
 
 static void InitializePredefinedMacros(const TargetInfo &TI,
                                        const LangOptions &LangOpts,
                                        const FrontendOptions &FEOpts,
                                        MacroBuilder &Builder) {
   // Compiler version introspection macros.
   Builder.defineMacro("__llvm__");  // LLVM Backend

test/Lexer/cxx-features.cpp

 // RUN: %clang_cc1 -std=c++98 -verify %s
 // RUN: %clang_cc1 -std=c++11 -verify %s
 // RUN: %clang_cc1 -std=c++1y -fsized-deallocation -verify %s
+// RUN: %clang_cc1 -std=c++1y -fsized-deallocation -fconcepts-ts -DCONCEPTS_TS=1 -verify %s
 
 // expected-no-diagnostics
 
 #if __cplusplus < 201103L
 #define check(macro, cxx98, cxx11, cxx1y) cxx98 == 0 ? defined(__cpp_##macro) : __cpp_##macro != cxx98
 #elif __cplusplus < 201304L
 #define check(macro, cxx98, cxx11, cxx1y) cxx11 == 0 ? defined(__cpp_##macro) : __cpp_##macro != cxx11
 #else

 
 #if check(ref_qualifiers, 0, 200710, 200710)
 #error "wrong value for __cpp_ref_qualifiers"
 #endif
 
 #if check(alias_templates, 0, 200704, 200704)
 #error "wrong value for __cpp_alias_templates"
 #endif
+
+#if check(experimental_concepts, 0, 0, CONCEPTS_TS)
+#error "wrong value for __cpp_experimental_concepts"
+#endif

www/cxx_status.html

</tr>
     </tr>
     <tr>
       <td>[DRAFT TS] Library fundamentals (invocation type traits)</td>
       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3908.html">N3908</a></td>
       <td class="none" align="center">No</td>
     </tr>
     <tr>
       <td>[DRAFT TS] Concepts</td>
-      <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3929.pdf">N3929</a></td>
+      <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4377.pdf">N4377</a></td>
       <td class="none" align="center">No</td>
     </tr>
 </table>
 
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