[c++1z] Most of N4268 (allow constant evaluation for non-type template arguments).

We don't yet support pointer-to-member template arguments that have undergone
pointer-to-member conversions, mostly because we don't have a mangling for them yet.

llvm-svn: 222807

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -64,6 +64,9 @@ def err_typecheck_converted_constant_expression : Error<
   "value of type %0 is not implicitly convertible to %1">;
 def err_typecheck_converted_constant_expression_disallowed : Error<
   "conversion from %0 to %1 is not allowed in a converted constant expression">;
+def err_typecheck_converted_constant_expression_indirect : Error<
+  "conversion from %0 to %1 in converted constant expression would "
+  "bind reference to a temporary">;
 def err_expr_not_cce : Error<
   "%select{case value|enumerator value|non-type template argument|array size}0 "
   "is not a constant expression">;
@@ -3293,6 +3296,10 @@ def err_template_arg_wrongtype_null_constant : Error<
 def err_deduced_non_type_template_arg_type_mismatch : Error<
   "deduced non-type template argument does not have the same type as the "
   "its corresponding template parameter%diff{ ($ vs $)|}0,1">;
+def err_non_type_template_arg_subobject : Error<
+  "non-type template argument refers to subobject '%0'">;
+def err_non_type_template_arg_addr_label_diff : Error<
+  "template argument / label address difference / what did you expect?">;
 def err_template_arg_not_convertible : Error<
   "non-type template argument of type %0 cannot be converted to a value "
   "of type %1">;
@@ -3344,6 +3351,9 @@ def err_template_arg_not_object_or_func : Error<
   "non-type template argument does not refer to an object or function">;
 def err_template_arg_not_pointer_to_member_form : Error<
   "non-type template argument is not a pointer to member constant">;
+def err_template_arg_member_ptr_base_derived_not_supported : Error<
+  "sorry, non-type template argument of pointer-to-member type %1 that refers "
+  "to member %q0 of a different class is not supported yet">;
 def ext_template_arg_extra_parens : ExtWarn<
   "address non-type template argument cannot be surrounded by parentheses">;
 def warn_cxx98_compat_template_arg_extra_parens : Warning<

clang/include/clang/Sema/Sema.h

@@ -2148,6 +2148,8 @@ public:
   };
   ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
                                               llvm::APSInt &Value, CCEKind CCE);
+  ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
+                                              APValue &Value, CCEKind CCE);
 
   /// \brief Abstract base class used to perform a contextual implicit
   /// conversion from an expression to any type passing a filter.

clang/lib/Sema/SemaExprCXX.cpp

@@ -2780,10 +2780,29 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType,
   // Perform the second implicit conversion
   switch (SCS.Second) {
   case ICK_Identity:
-    // If both sides are functions (or pointers/references to them), there could
-    // be incompatible exception declarations.
-    if (CheckExceptionSpecCompatibility(From, ToType))
-      return ExprError();
+    // C++ [except.spec]p5:
+    //   [For] assignment to and initialization of pointers to functions,
+    //   pointers to member functions, and references to functions: the
+    //   target entity shall allow at least the exceptions allowed by the
+    //   source value in the assignment or initialization.
+    switch (Action) {
+    case AA_Assigning:
+    case AA_Initializing:
+      // Note, function argument passing and returning are initialization.
+    case AA_Passing:
+    case AA_Returning:
+    case AA_Sending:
+    case AA_Passing_CFAudited:
+      if (CheckExceptionSpecCompatibility(From, ToType))
+        return ExprError();
+      break;
+
+    case AA_Casting:
+    case AA_Converting:
+      // Casts and implicit conversions are not initialization, so are not
+      // checked for exception specification mismatches.
+      break;
+    }
     // Nothing else to do.
     break;
 

clang/lib/Sema/SemaOverload.cpp

@@ -4894,41 +4894,51 @@ static bool CheckConvertedConstantConversions(Sema &S,
   // conversions are fine.
   switch (SCS.Second) {
   case ICK_Identity:
+  case ICK_NoReturn_Adjustment:
   case ICK_Integral_Promotion:
-  case ICK_Integral_Conversion:
-  case ICK_Zero_Event_Conversion:
+  case ICK_Integral_Conversion: // Narrowing conversions are checked elsewhere.
     return true;
 
   case ICK_Boolean_Conversion:
     // Conversion from an integral or unscoped enumeration type to bool is
-    // classified as ICK_Boolean_Conversion, but it's also an integral
-    // conversion, so it's permitted in a converted constant expression.
+    // classified as ICK_Boolean_Conversion, but it's also arguably an integral
+    // conversion, so we allow it in a converted constant expression.
+    //
+    // FIXME: Per core issue 1407, we should not allow this, but that breaks
+    // a lot of popular code. We should at least add a warning for this
+    // (non-conforming) extension.
     return SCS.getFromType()->isIntegralOrUnscopedEnumerationType() &&
            SCS.getToType(2)->isBooleanType();
 
+  case ICK_Pointer_Conversion:
+  case ICK_Pointer_Member:
+    // C++1z: null pointer conversions and null member pointer conversions are
+    // only permitted if the source type is std::nullptr_t.
+    return SCS.getFromType()->isNullPtrType();
+
+  case ICK_Floating_Promotion:
+  case ICK_Complex_Promotion:
+  case ICK_Floating_Conversion:
+  case ICK_Complex_Conversion:
   case ICK_Floating_Integral:
+  case ICK_Compatible_Conversion:
+  case ICK_Derived_To_Base:
+  case ICK_Vector_Conversion:
+  case ICK_Vector_Splat:
   case ICK_Complex_Real:
+  case ICK_Block_Pointer_Conversion:
+  case ICK_TransparentUnionConversion:
+  case ICK_Writeback_Conversion:
+  case ICK_Zero_Event_Conversion:
     return false;
 
   case ICK_Lvalue_To_Rvalue:
   case ICK_Array_To_Pointer:
   case ICK_Function_To_Pointer:
-  case ICK_NoReturn_Adjustment:
+    llvm_unreachable("found a first conversion kind in Second");
+
   case ICK_Qualification:
-  case ICK_Compatible_Conversion:
-  case ICK_Vector_Conversion:
-  case ICK_Vector_Splat:
-  case ICK_Derived_To_Base:
-  case ICK_Pointer_Conversion:
-  case ICK_Pointer_Member:
-  case ICK_Block_Pointer_Conversion:
-  case ICK_Writeback_Conversion:
-  case ICK_Floating_Promotion:
-  case ICK_Complex_Promotion:
-  case ICK_Complex_Conversion:
-  case ICK_Floating_Conversion:
-  case ICK_TransparentUnionConversion:
-    llvm_unreachable("unexpected second conversion kind");
+    llvm_unreachable("found a third conversion kind in Second");
 
   case ICK_Num_Conversion_Kinds:
     break;
@@ -4940,67 +4950,71 @@ static bool CheckConvertedConstantConversions(Sema &S,
 /// CheckConvertedConstantExpression - Check that the expression From is a
 /// converted constant expression of type T, perform the conversion and produce
 /// the converted expression, per C++11 [expr.const]p3.
-ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
-                                                  llvm::APSInt &Value,
-                                                  CCEKind CCE) {
-  assert(LangOpts.CPlusPlus11 && "converted constant expression outside C++11");
-  assert(T->isIntegralOrEnumerationType() && "unexpected converted const type");
+static ExprResult CheckConvertedConstantExpression(Sema &S, Expr *From,
+                                                   QualType T, APValue &Value,
+                                                   Sema::CCEKind CCE,
+                                                   bool RequireInt) {
+  assert(S.getLangOpts().CPlusPlus11 &&
+         "converted constant expression outside C++11");
 
-  if (checkPlaceholderForOverload(*this, From))
+  if (checkPlaceholderForOverload(S, From))
     return ExprError();
 
-  // C++11 [expr.const]p3 with proposed wording fixes:
-  //  A converted constant expression of type T is a core constant expression,
-  //  implicitly converted to a prvalue of type T, where the converted
-  //  expression is a literal constant expression and the implicit conversion
-  //  sequence contains only user-defined conversions, lvalue-to-rvalue
-  //  conversions, integral promotions, and integral conversions other than
-  //  narrowing conversions.
+  // C++1z [expr.const]p3:
+  //  A converted constant expression of type T is an expression,
+  //  implicitly converted to type T, where the converted
+  //  expression is a constant expression and the implicit conversion
+  //  sequence contains only [... list of conversions ...].
   ImplicitConversionSequence ICS =
-    TryImplicitConversion(From, T,
+    TryCopyInitialization(S, From, T,
                           /*SuppressUserConversions=*/false,
-                          /*AllowExplicit=*/false,
                           /*InOverloadResolution=*/false,
-                          /*CStyle=*/false,
-                          /*AllowObjcWritebackConversion=*/false);
+                          /*AllowObjcWritebackConversion=*/false,
+                          /*AllowExplicit=*/false);
   StandardConversionSequence *SCS = nullptr;
   switch (ICS.getKind()) {
   case ImplicitConversionSequence::StandardConversion:
-    if (!CheckConvertedConstantConversions(*this, ICS.Standard))
-      return Diag(From->getLocStart(),
-                  diag::err_typecheck_converted_constant_expression_disallowed)
-               << From->getType() << From->getSourceRange() << T;
     SCS = &ICS.Standard;
     break;
   case ImplicitConversionSequence::UserDefinedConversion:
-    // We are converting from class type to an integral or enumeration type, so
-    // the Before sequence must be trivial.
-    if (!CheckConvertedConstantConversions(*this, ICS.UserDefined.After))
-      return Diag(From->getLocStart(),
-                  diag::err_typecheck_converted_constant_expression_disallowed)
-               << From->getType() << From->getSourceRange() << T;
+    // We are converting to a non-class type, so the Before sequence
+    // must be trivial.
     SCS = &ICS.UserDefined.After;
     break;
   case ImplicitConversionSequence::AmbiguousConversion:
   case ImplicitConversionSequence::BadConversion:
-    if (!DiagnoseMultipleUserDefinedConversion(From, T))
-      return Diag(From->getLocStart(),
-                  diag::err_typecheck_converted_constant_expression)
-                    << From->getType() << From->getSourceRange() << T;
+    if (!S.DiagnoseMultipleUserDefinedConversion(From, T))
+      return S.Diag(From->getLocStart(),
+                    diag::err_typecheck_converted_constant_expression)
+                << From->getType() << From->getSourceRange() << T;
     return ExprError();
 
   case ImplicitConversionSequence::EllipsisConversion:
     llvm_unreachable("ellipsis conversion in converted constant expression");
   }
 
-  ExprResult Result = PerformImplicitConversion(From, T, ICS, AA_Converting);
+  // Check that we would only use permitted conversions.
+  if (!CheckConvertedConstantConversions(S, *SCS)) {
+    return S.Diag(From->getLocStart(),
+                  diag::err_typecheck_converted_constant_expression_disallowed)
+             << From->getType() << From->getSourceRange() << T;
+  }
+  // [...] and where the reference binding (if any) binds directly.
+  if (SCS->ReferenceBinding && !SCS->DirectBinding) {
+    return S.Diag(From->getLocStart(),
+                  diag::err_typecheck_converted_constant_expression_indirect)
+             << From->getType() << From->getSourceRange() << T;
+  }
+
+  ExprResult Result =
+      S.PerformImplicitConversion(From, T, ICS, Sema::AA_Converting);
   if (Result.isInvalid())
     return Result;
 
   // Check for a narrowing implicit conversion.
   APValue PreNarrowingValue;
   QualType PreNarrowingType;
-  switch (SCS->getNarrowingKind(Context, Result.get(), PreNarrowingValue,
+  switch (SCS->getNarrowingKind(S.Context, Result.get(), PreNarrowingValue,
                                 PreNarrowingType)) {
   case NK_Variable_Narrowing:
     // Implicit conversion to a narrower type, and the value is not a constant
@@ -5009,13 +5023,13 @@ ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
     break;
 
   case NK_Constant_Narrowing:
-    Diag(From->getLocStart(), diag::ext_cce_narrowing)
+    S.Diag(From->getLocStart(), diag::ext_cce_narrowing)
       << CCE << /*Constant*/1
-      << PreNarrowingValue.getAsString(Context, PreNarrowingType) << T;
+      << PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << T;
     break;
 
   case NK_Type_Narrowing:
-    Diag(From->getLocStart(), diag::ext_cce_narrowing)
+    S.Diag(From->getLocStart(), diag::ext_cce_narrowing)
       << CCE << /*Constant*/0 << From->getType() << T;
     break;
   }
@@ -5025,12 +5039,15 @@ ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
   Expr::EvalResult Eval;
   Eval.Diag = &Notes;
 
-  if (!Result.get()->EvaluateAsRValue(Eval, Context) || !Eval.Val.isInt()) {
+  if ((T->isReferenceType()
+           ? !Result.get()->EvaluateAsLValue(Eval, S.Context)
+           : !Result.get()->EvaluateAsRValue(Eval, S.Context)) ||
+      (RequireInt && !Eval.Val.isInt())) {
     // The expression can't be folded, so we can't keep it at this position in
     // the AST.
     Result = ExprError();
   } else {
-    Value = Eval.Val.getInt();
+    Value = Eval.Val;
 
     if (Notes.empty()) {
       // It's a constant expression.
@@ -5041,16 +5058,34 @@ ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
   // It's not a constant expression. Produce an appropriate diagnostic.
   if (Notes.size() == 1 &&
       Notes[0].second.getDiagID() == diag::note_invalid_subexpr_in_const_expr)
-    Diag(Notes[0].first, diag::err_expr_not_cce) << CCE;
+    S.Diag(Notes[0].first, diag::err_expr_not_cce) << CCE;
   else {
-    Diag(From->getLocStart(), diag::err_expr_not_cce)
+    S.Diag(From->getLocStart(), diag::err_expr_not_cce)
       << CCE << From->getSourceRange();
     for (unsigned I = 0; I < Notes.size(); ++I)
-      Diag(Notes[I].first, Notes[I].second);
+      S.Diag(Notes[I].first, Notes[I].second);
   }
-  return Result;
+  return ExprError();
 }
 
+ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
+                                                  APValue &Value, CCEKind CCE) {
+  return ::CheckConvertedConstantExpression(*this, From, T, Value, CCE, false);
+}
+
+ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
+                                                  llvm::APSInt &Value,
+                                                  CCEKind CCE) {
+  assert(T->isIntegralOrEnumerationType() && "unexpected converted const type");
+
+  APValue V;
+  auto R = ::CheckConvertedConstantExpression(*this, From, T, V, CCE, true);
+  if (!R.isInvalid())
+    Value = V.getInt();
+  return R;
+}
+
+
 /// dropPointerConversions - If the given standard conversion sequence
 /// involves any pointer conversions, remove them.  This may change
 /// the result type of the conversion sequence.

clang/lib/Sema/SemaTemplate.cpp

@@ -4759,13 +4759,111 @@ ExprResult Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
     return Arg;
   }
 
+  QualType ParamType = InstantiatedParamType;
+  if (getLangOpts().CPlusPlus1z) {
+    // FIXME: We can do some limited checking for a value-dependent but not
+    // type-dependent argument.
+    if (Arg->isValueDependent()) {
+      Converted = TemplateArgument(Arg);
+      return Arg;
+    }
+
+    // C++1z [temp.arg.nontype]p1:
+    //   A template-argument for a non-type template parameter shall be
+    //   a converted constant expression of the type of the template-parameter.
+    APValue Value;
+    ExprResult ArgResult = CheckConvertedConstantExpression(
+        Arg, ParamType, Value, CCEK_TemplateArg);
+    if (ArgResult.isInvalid())
+      return ExprError();
+
+    // Convert the APValue to a TemplateArgument.
+    switch (Value.getKind()) {
+    case APValue::Uninitialized:
+      assert(ParamType->isNullPtrType());
+      Converted = TemplateArgument(ParamType, /*isNullPtr*/true);
+      break;
+    case APValue::Int:
+      assert(ParamType->isIntegralOrEnumerationType());
+      Converted = TemplateArgument(Context, Value.getInt(), ParamType);
+      break;
+    case APValue::MemberPointer: {
+      assert(ParamType->isMemberPointerType());
+
+      // FIXME: We need TemplateArgument representation and mangling for these.
+      if (!Value.getMemberPointerPath().empty()) {
+        Diag(Arg->getLocStart(),
+             diag::err_template_arg_member_ptr_base_derived_not_supported)
+            << Value.getMemberPointerDecl() << ParamType
+            << Arg->getSourceRange();
+        return ExprError();
+      }
+
+      auto *VD = const_cast<ValueDecl*>(Value.getMemberPointerDecl());
+      Converted = VD ? TemplateArgument(VD, ParamType)
+                     : TemplateArgument(ParamType, /*isNullPtr*/true);
+      break;
+    }
+    case APValue::LValue: {
+      //   For a non-type template-parameter of pointer or reference type,
+      //   the value of the constant expression shall not refer to
+      assert(ParamType->isPointerType() || ParamType->isReferenceType());
+      // -- a temporary object
+      // -- a string literal
+      // -- the result of a typeid expression, or
+      // -- a predefind __func__ variable
+      if (auto *E = Value.getLValueBase().dyn_cast<const Expr*>()) {
+        if (isa<CXXUuidofExpr>(E)) {
+          Converted = TemplateArgument(const_cast<Expr*>(E));
+          break;
+        }
+        Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
+          << Arg->getSourceRange();
+        return ExprError();
+      }
+      auto *VD = const_cast<ValueDecl *>(
+          Value.getLValueBase().dyn_cast<const ValueDecl *>());
+      // -- a subobject
+      if (Value.hasLValuePath() && Value.getLValuePath().size() == 1 &&
+          VD && VD->getType()->isArrayType() &&
+          Value.getLValuePath()[0].ArrayIndex == 0 &&
+          !Value.isLValueOnePastTheEnd() && ParamType->isPointerType()) {
+        // Per defect report (no number yet):
+        //   ... other than a pointer to the first element of a complete array
+        //       object.
+      } else if (!Value.hasLValuePath() || Value.getLValuePath().size() ||
+                 Value.isLValueOnePastTheEnd()) {
+        Diag(StartLoc, diag::err_non_type_template_arg_subobject)
+          << Value.getAsString(Context, ParamType);
+        return ExprError();
+      }
+      assert((VD || ParamType->isPointerType()) &&
+             "null reference should not be a constant expression");
+      Converted = VD ? TemplateArgument(VD, ParamType)
+                     : TemplateArgument(ParamType, /*isNullPtr*/true);
+      break;
+    }
+    case APValue::AddrLabelDiff:
+      return Diag(StartLoc, diag::err_non_type_template_arg_addr_label_diff);
+    case APValue::Float:
+    case APValue::ComplexInt:
+    case APValue::ComplexFloat:
+    case APValue::Vector:
+    case APValue::Array:
+    case APValue::Struct:
+    case APValue::Union:
+      llvm_unreachable("invalid kind for template argument");
+    }
+
+    return ArgResult.get();
+  }
+
   // C++ [temp.arg.nontype]p5:
   //   The following conversions are performed on each expression used
   //   as a non-type template-argument. If a non-type
   //   template-argument cannot be converted to the type of the
   //   corresponding template-parameter then the program is
   //   ill-formed.
-  QualType ParamType = InstantiatedParamType;
   if (ParamType->isIntegralOrEnumerationType()) {
     // C++11:
     //   -- for a non-type template-parameter of integral or

clang/test/CXX/drs/dr0xx.cpp

@@ -521,17 +521,28 @@ namespace dr48 { // dr48: yes
 }
 
 namespace dr49 { // dr49: yes
-  template<int*> struct A {}; // expected-note {{here}}
+  template<int*> struct A {}; // expected-note 0-2{{here}}
   int k;
 #if __has_feature(cxx_constexpr)
   constexpr
 #endif
-  int *const p = &k;
+  int *const p = &k; // expected-note 0-2{{here}}
   A<&k> a;
-  A<p> b; // expected-error {{must have its address taken}}
+  A<p> b;
+#if __cplusplus <= 201402L
+  // expected-error@-2 {{must have its address taken}}
+#endif
 #if __cplusplus < 201103L
-  // expected-error@-2 {{internal linkage}}
-  // expected-note@-5 {{here}}
+  // expected-error@-5 {{internal linkage}}
+#endif
+  int *q = &k;
+  A<q> c;
+#if __cplusplus < 201103L
+  // expected-error@-2 {{must have its address taken}}
+#else
+  // expected-error@-4 {{constant expression}}
+  // expected-note@-5 {{read of non-constexpr}}
+  // expected-note@-7 {{declared here}}
 #endif
 }
 
@@ -995,6 +1006,10 @@ namespace dr92 { // dr92: yes
     g(q); // expected-error {{is not superset}}
   }
 
+  // Prior to C++17, this is OK because the exception specification is not
+  // considered in this context. In C++17, we *do* perform an implicit
+  // conversion (which performs initialization), but we convert to the type of
+  // the template parameter, which does not include the exception specification.
   template<void() throw()> struct X {};
   X<&f> xp; // ok
 }

clang/test/CXX/drs/dr1xx.cpp

@@ -4,8 +4,8 @@
 // RUN: %clang_cc1 -std=c++1z -triple x86_64-unknown-unknown %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
 
 namespace dr100 { // dr100: yes
-  template<const char *> struct A {}; // expected-note {{declared here}}
-  template<const char (&)[4]> struct B {}; // expected-note {{declared here}}
+  template<const char *> struct A {}; // expected-note 0-1{{declared here}}
+  template<const char (&)[4]> struct B {}; // expected-note 0-1{{declared here}}
   A<"foo"> a; // expected-error {{does not refer to any declaration}}
   B<"bar"> b; // expected-error {{does not refer to any declaration}}
 }

clang/test/CXX/drs/dr2xx.cpp

@@ -991,12 +991,11 @@ namespace dr289 { // dr289: yes
 namespace dr294 { // dr294: no
   void f() throw(int);
   int main() {
-    // FIXME: we reject this for the wrong reason, because we don't implement
-    // dr87 yet.
-    (void)static_cast<void (*)() throw()>(f); // expected-error {{not superset}}
-    void (*p)() throw() = f; // expected-error {{not superset}}
-
+    (void)static_cast<void (*)() throw()>(f); // FIXME: ill-formed
     (void)static_cast<void (*)() throw(int)>(f); // FIXME: ill-formed
+
+    void (*p)() throw() = f; // expected-error {{not superset}}
+    void (*q)() throw(int) = f;
   }
 }
 

clang/test/CXX/drs/dr3xx.cpp

@@ -705,7 +705,7 @@ namespace dr354 { // dr354: yes c++11
   // FIXME: Should we allow this in C++98 too?
   struct S {};
 
-  template<int*> struct ptr {}; // expected-note +{{here}}
+  template<int*> struct ptr {}; // expected-note 0-4{{here}}
   ptr<0> p0;
   ptr<(int*)0> p1;
   ptr<(float*)0> p2;
@@ -715,11 +715,16 @@ namespace dr354 { // dr354: yes c++11
   // expected-error@-5 {{does not refer to any decl}}
   // expected-error@-5 {{does not refer to any decl}}
   // expected-error@-5 {{does not refer to any decl}}
-#else
+#elif __cplusplus <= 201402L
   // expected-error@-10 {{must be cast}}
   // ok
   // expected-error@-10 {{does not match}}
   // expected-error@-10 {{does not match}}
+#else
+  // expected-error@-15 {{conversion from 'int' to 'int *' is not allowed}}
+  // ok
+  // expected-error@-15 {{'float *' is not implicitly convertible to 'int *'}}
+  // expected-error@-15 {{'int dr354::S::*' is not implicitly convertible to 'int *'}}
 #endif
 
   template<int*> int both();
@@ -732,7 +737,7 @@ namespace dr354 { // dr354: yes c++11
   // expected-note@-6 {{candidate}}
 #endif
 
-  template<int S::*> struct ptr_mem {}; // expected-note +{{here}}
+  template<int S::*> struct ptr_mem {}; // expected-note 0-4{{here}}
   ptr_mem<0> m0;
   ptr_mem<(int S::*)0> m1;
   ptr_mem<(float S::*)0> m2;
@@ -742,11 +747,16 @@ namespace dr354 { // dr354: yes c++11
   // expected-error@-5 {{is not a pointer to member constant}}
   // expected-error@-5 {{cannot be converted}}
   // expected-error@-5 {{cannot be converted}}
-#else
+#elif __cplusplus <= 201402L
   // expected-error@-10 {{must be cast}}
   // ok
   // expected-error@-10 {{does not match}}
   // expected-error@-10 {{does not match}}
+#else
+  // expected-error@-15 {{conversion from 'int' to 'int dr354::S::*' is not allowed}}
+  // ok
+  // expected-error@-15 {{'float dr354::S::*' is not implicitly convertible to 'int dr354::S::*'}}
+  // expected-error@-15 {{'int *' is not implicitly convertible to 'int dr354::S::*'}}
 #endif
 }
 

clang/test/CXX/expr/expr.const/p2-0x.cpp

@@ -131,14 +131,14 @@ namespace IncompleteClassTypeAddr {
 namespace UndefinedBehavior {
   void f(int n) {
     switch (n) {
-    case (int)4.4e9: // expected-error {{constant expression}} expected-note {{value 4.4E+9 is outside the range of representable values of type 'int'}} expected-note {{previous case defined here}}
+    case (int)4.4e9: // expected-error {{constant expression}} expected-note {{value 4.4E+9 is outside the range of representable values of type 'int'}}
     case (int)0x80000000u: // ok
     case (int)10000000000ll: // expected-note {{here}}
     case (unsigned int)10000000000ll: // expected-error {{duplicate case value}}
     case (int)(unsigned)(long long)4.4e9: // ok
-    case (int)(float)1e300: // expected-error {{constant expression}} expected-note {{value 1.0E+300 is outside the range of representable values of type 'float'}} expected-error {{duplicate case value '2147483647'}} expected-note {{previous case defined here}}
+    case (int)(float)1e300: // expected-error {{constant expression}} expected-note {{value 1.0E+300 is outside the range of representable values of type 'float'}}
     case (int)((float)1e37 / 1e30): // ok
-    case (int)(__fp16)65536: // expected-error {{constant expression}} expected-note {{value 65536 is outside the range of representable values of type '__fp16'}} expected-error {{duplicate case value '2147483647'}}
+    case (int)(__fp16)65536: // expected-error {{constant expression}} expected-note {{value 65536 is outside the range of representable values of type '__fp16'}}
       break;
     }
   }

clang/test/SemaTemplate/temp_arg_nontype_cxx1z.cpp

@@ -0,0 +1,112 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z %s
+
+template<typename T, T val> struct A {};
+
+template<typename T, typename U> constexpr bool is_same = false; // expected-note +{{here}}
+template<typename T> constexpr bool is_same<T, T> = true;
+
+namespace String {
+  A<const char*, "test"> a; // expected-error {{does not refer to any declaration}}
+  A<const char (&)[5], "test"> b; // expected-error {{does not refer to any declaration}}
+}
+
+namespace Array {
+  char arr[3];
+  char x;
+  A<const char*, arr> a;
+  A<const char(&)[3], arr> b;
+  A<const char*, &arr[0]> c;
+  A<const char*, &arr[1]> d; // expected-error {{refers to subobject '&arr[1]'}}
+  A<const char*, (&arr)[0]> e;
+  A<const char*, &x> f;
+  A<const char*, &(&x)[0]> g;
+  A<const char*, &(&x)[1]> h; // expected-error {{refers to subobject '&x + 1'}}
+  A<const char*, 0> i; // expected-error {{not allowed in a converted constant}}
+  A<const char*, nullptr> j;
+}
+
+namespace Function {
+  void f();
+  void g() noexcept;
+  void h();
+  void h(int);
+  template<typename...T> void i(T...);
+  typedef A<void (*)(), f> a;
+  typedef A<void (*)(), &f> a;
+  typedef A<void (*)(), g> b;
+  typedef A<void (*)(), &g> b;
+  typedef A<void (*)(), h> c;
+  typedef A<void (*)(), &h> c;
+  typedef A<void (*)(), i> d;
+  typedef A<void (*)(), &i> d;
+  typedef A<void (*)(), i<>> d;
+  typedef A<void (*)(), i<int>> e; // expected-error {{is not implicitly convertible}}
+
+  typedef A<void (*)(), 0> x; // expected-error {{not allowed in a converted constant}}
+  typedef A<void (*)(), nullptr> y;
+}
+
+void Func() {
+  A<const char*, __func__> a; // expected-error {{does not refer to any declaration}}
+}
+
+namespace LabelAddrDiff {
+  void f() {
+    a: b: A<int, __builtin_constant_p(true) ? (long)&&b - (long)&&a : 0> s; // expected-error {{label address difference}}
+  };
+}
+
+namespace Temp {
+  struct S { int n; };
+  constexpr S &addr(S &&s) { return s; }
+  A<S &, addr({})> a; // expected-error {{constant}} expected-note 2{{temporary}}
+  A<S *, &addr({})> b; // expected-error {{constant}} expected-note 2{{temporary}}
+  A<int &, addr({}).n> c; // expected-error {{constant}} expected-note 2{{temporary}}
+  A<int *, &addr({}).n> d; // expected-error {{constant}} expected-note 2{{temporary}}
+}
+
+namespace std { struct type_info; }
+
+namespace RTTI {
+  A<const std::type_info&, typeid(int)> a; // expected-error {{does not refer to any declaration}}
+  A<const std::type_info*, &typeid(int)> b; // expected-error {{does not refer to any declaration}}
+}
+
+namespace PtrMem {
+  struct B { int b; };
+  struct C : B {};
+  struct D : B {};
+  struct E : C, D { int e; };
+
+  constexpr int B::*b = &B::b;
+  constexpr int C::*cb = b;
+  constexpr int D::*db = b;
+  constexpr int E::*ecb = cb; // expected-note +{{here}}
+  constexpr int E::*edb = db; // expected-note +{{here}}
+
+  constexpr int E::*e = &E::e;
+  constexpr int D::*de = (int D::*)e;
+  constexpr int C::*ce = (int C::*)e;
+  constexpr int B::*bde = (int B::*)de; // expected-note +{{here}}
+  constexpr int B::*bce = (int B::*)ce; // expected-note +{{here}}
+
+  // FIXME: This should all be accepted, but we don't yet have a representation
+  // nor mangling for this form of template argument.
+  using Ab = A<int B::*, b>;
+  using Ab = A<int B::*, &B::b>;
+  using Abce = A<int B::*, bce>; // expected-error {{not supported}}
+  using Abde = A<int B::*, bde>; // expected-error {{not supported}}
+  static_assert(!is_same<Ab, Abce>, ""); // expected-error {{undeclared}} expected-error {{must be a type}}
+  static_assert(!is_same<Ab, Abde>, ""); // expected-error {{undeclared}} expected-error {{must be a type}}
+  static_assert(!is_same<Abce, Abde>, ""); // expected-error 2{{undeclared}} expected-error {{must be a type}}
+  static_assert(is_same<Abce, A<int B::*, (int B::*)(int C::*)&E::e>, ""); // expected-error {{undeclared}} expected-error {{not supported}}
+
+  using Ae = A<int E::*, e>;
+  using Ae = A<int E::*, &E::e>;
+  using Aecb = A<int E::*, ecb>; // expected-error {{not supported}}
+  using Aedb = A<int E::*, edb>; // expected-error {{not supported}}
+  static_assert(!is_same<Ae, Aecb>, ""); // expected-error {{undeclared}} expected-error {{must be a type}}
+  static_assert(!is_same<Ae, Aedb>, ""); // expected-error {{undeclared}} expected-error {{must be a type}}
+  static_assert(!is_same<Aecb, Aedb>, ""); // expected-error 2{{undeclared}} expected-error {{must be a type}}
+  static_assert(is_same<Aecb, A<int E::*, (int E::*)(int C::*)&B::b>, ""); // expected-error {{undeclared}} expected-error {{not supported}}
+}

clang/www/cxx_status.html

@@ -533,7 +533,7 @@ as the draft C++1z standard evolves.</p>
     <!-- Rapperswil papers -->
     <tr>
       <td>Disabling trigraph expansion by default</td>
-      <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3981.html">N3981</a></td>
+      <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4086.html">N4086</a></td>
       <td class="full" align="center">Clang 3.5</td>
     </tr>
     <tr>
@@ -546,6 +546,11 @@ as the draft C++1z standard evolves.</p>
       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4051.html">N4051</a></td>
       <td class="full" align="center">Clang 3.5</td>
     </tr>
+    <tr>
+      <td>New <tt>auto</tt> rules for direct-list-initialization
+      <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3922.html">N3922</a></td>
+      <td class="no" align="center">No</td>
+    </tr>
     <!-- Urbana papers -->
     <tr>
       <td>Fold expressions</td>
@@ -567,6 +572,11 @@ as the draft C++1z standard evolves.</p>
       <td><!--<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4266.html">-->N4266<!--</a>--></td>
       <td class="svn" align="center">SVN</td>
     </tr>
+    <tr>
+      <td>Allow constant evaluation for all non-type template arguments</td>
+      <td><!--<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4268.html">-->N4268<!--</a>--></td>
+      <td class="svn" align="center">SVN</td>
+    </tr>
 </table>
 
 <h2 id="ts">Technical specifications and standing documents</h2>