r360974 - Refactor constant evaluation of typeid(T) to track a symbolic type_info
Chris Bieneman via cfe-commits
cfe-commits at lists.llvm.org
Thu May 16 22:14:00 PDT 2019
Sorry to do this, but I'm also reverting r360977, because it seems to be on top of this one.
-Chris
> On May 16, 2019, at 9:58 PM, Chris Bieneman via cfe-commits <cfe-commits at lists.llvm.org> wrote:
>
> Hey Richard,
>
> This change is tripping up a bunch of the bots:
>
> http://lab.llvm.org:8011/builders/clang-cmake-armv8-lld/builds/1397
>
> I'm going to revert it so that we don't leave the bots broken overnight.
>
> -Chris
>
>> On May 16, 2019, at 6:46 PM, Richard Smith via cfe-commits <cfe-commits at lists.llvm.org> wrote:
>>
>> Author: rsmith
>> Date: Thu May 16 18:46:05 2019
>> New Revision: 360974
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=360974&view=rev
>> Log:
>> Refactor constant evaluation of typeid(T) to track a symbolic type_info
>> object rather than tracking the originating expression.
>>
>> This is groundwork for supporting polymorphic typeid expressions. (Note
>> that this somewhat regresses our support for DR1968, but it turns out
>> that that never actually worked anyway, at least in non-trivial cases.)
>>
>> Modified:
>> cfe/trunk/include/clang/AST/APValue.h
>> cfe/trunk/include/clang/Basic/DiagnosticASTKinds.td
>> cfe/trunk/lib/AST/APValue.cpp
>> cfe/trunk/lib/AST/ExprConstant.cpp
>> cfe/trunk/lib/CodeGen/CGExprConstant.cpp
>> cfe/trunk/lib/Sema/SemaTemplate.cpp
>> cfe/trunk/test/CXX/drs/dr19xx.cpp
>> cfe/trunk/test/Parser/MicrosoftExtensions.cpp
>> cfe/trunk/test/SemaCXX/builtin-constant-p.cpp
>> cfe/trunk/test/SemaCXX/typeid.cpp
>> cfe/trunk/www/cxx_dr_status.html
>>
>> Modified: cfe/trunk/include/clang/AST/APValue.h
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/APValue.h?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/include/clang/AST/APValue.h (original)
>> +++ cfe/trunk/include/clang/AST/APValue.h Thu May 16 18:46:05 2019
>> @@ -24,14 +24,52 @@ namespace clang {
>> class AddrLabelExpr;
>> class ASTContext;
>> class CharUnits;
>> + class CXXRecordDecl;
>> + class Decl;
>> class DiagnosticBuilder;
>> class Expr;
>> class FieldDecl;
>> - class Decl;
>> + struct PrintingPolicy;
>> + class Type;
>> class ValueDecl;
>> - class CXXRecordDecl;
>> - class QualType;
>>
>> +/// Symbolic representation of typeid(T) for some type T.
>> +class TypeInfoLValue {
>> + const Type *T;
>> +
>> +public:
>> + TypeInfoLValue() : T() {}
>> + explicit TypeInfoLValue(const Type *T);
>> +
>> + const Type *getType() const { return T; }
>> + explicit operator bool() const { return T; }
>> +
>> + void *getOpaqueValue() { return const_cast<Type*>(T); }
>> + static TypeInfoLValue getFromOpaqueValue(void *Value) {
>> + TypeInfoLValue V;
>> + V.T = reinterpret_cast<const Type*>(Value);
>> + return V;
>> + }
>> +
>> + void print(llvm::raw_ostream &Out, const PrintingPolicy &Policy) const;
>> +};
>> +}
>> +
>> +namespace llvm {
>> +template<> struct PointerLikeTypeTraits<clang::TypeInfoLValue> {
>> + static void *getAsVoidPointer(clang::TypeInfoLValue V) {
>> + return V.getOpaqueValue();
>> + }
>> + static clang::TypeInfoLValue getFromVoidPointer(void *P) {
>> + return clang::TypeInfoLValue::getFromOpaqueValue(P);
>> + }
>> + // Validated by static_assert in APValue.cpp; hardcoded to avoid needing
>> + // to include Type.h.
>> + static constexpr int NumLowBitsAvailable = 3;
>> +};
>> +}
>> +
>> +namespace clang {
>> /// APValue - This class implements a discriminated union of [uninitialized]
>> /// [APSInt] [APFloat], [Complex APSInt] [Complex APFloat], [Expr + Offset],
>> /// [Vector: N * APValue], [Array: N * APValue]
>> @@ -57,13 +95,18 @@ public:
>>
>> class LValueBase {
>> public:
>> - typedef llvm::PointerUnion<const ValueDecl *, const Expr *> PtrTy;
>> + typedef llvm::PointerUnion<const ValueDecl *, const Expr *, TypeInfoLValue>
>> + PtrTy;
>>
>> - LValueBase() : CallIndex(0), Version(0) {}
>> + LValueBase() : Local{} {}
>>
>> template <class T>
>> - LValueBase(T P, unsigned I = 0, unsigned V = 0)
>> - : Ptr(P), CallIndex(I), Version(V) {}
>> + LValueBase(T P, unsigned I = 0, unsigned V = 0) : Ptr(P), Local{I, V} {
>> + assert(!is<TypeInfoLValue>() &&
>> + "don't use this constructor to form a type_info lvalue");
>> + }
>> +
>> + static LValueBase getTypeInfo(TypeInfoLValue LV, QualType TypeInfo);
>>
>> template <class T>
>> bool is() const { return Ptr.is<T>(); }
>> @@ -78,28 +121,15 @@ public:
>>
>> bool isNull() const;
>>
>> - explicit operator bool () const;
>> + explicit operator bool() const;
>>
>> - PtrTy getPointer() const {
>> - return Ptr;
>> - }
>> + PtrTy getPointer() const { return Ptr; }
>>
>> - unsigned getCallIndex() const {
>> - return CallIndex;
>> - }
>> + unsigned getCallIndex() const;
>> + unsigned getVersion() const;
>> + QualType getTypeInfoType() const;
>>
>> - void setCallIndex(unsigned Index) {
>> - CallIndex = Index;
>> - }
>> -
>> - unsigned getVersion() const {
>> - return Version;
>> - }
>> -
>> - friend bool operator==(const LValueBase &LHS, const LValueBase &RHS) {
>> - return LHS.Ptr == RHS.Ptr && LHS.CallIndex == RHS.CallIndex &&
>> - LHS.Version == RHS.Version;
>> - }
>> + friend bool operator==(const LValueBase &LHS, const LValueBase &RHS);
>> friend bool operator!=(const LValueBase &LHS, const LValueBase &RHS) {
>> return !(LHS == RHS);
>> }
>> @@ -107,7 +137,14 @@ public:
>>
>> private:
>> PtrTy Ptr;
>> - unsigned CallIndex, Version;
>> + struct LocalState {
>> + unsigned CallIndex, Version;
>> + };
>> + union {
>> + LocalState Local;
>> + /// The type std::type_info, if this is a TypeInfoLValue.
>> + void *TypeInfoType;
>> + };
>> };
>>
>> /// A FieldDecl or CXXRecordDecl, along with a flag indicating whether we
>>
>> Modified: cfe/trunk/include/clang/Basic/DiagnosticASTKinds.td
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticASTKinds.td?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/include/clang/Basic/DiagnosticASTKinds.td (original)
>> +++ cfe/trunk/include/clang/Basic/DiagnosticASTKinds.td Thu May 16 18:46:05 2019
>> @@ -160,6 +160,9 @@ def note_constexpr_access_static_tempora
>> "dynamic_cast of}0 temporary "
>> "is not allowed in a constant expression outside the expression that "
>> "created the temporary">;
>> +def note_constexpr_access_unreadable_object : Note<
>> + "%select{read of|assignment to|increment of|decrement of|member call on|"
>> + "dynamic_cast of}0 object '%1' whose value is not known">;
>> def note_constexpr_modify_global : Note<
>> "a constant expression cannot modify an object that is visible outside "
>> "that expression">;
>>
>> Modified: cfe/trunk/lib/AST/APValue.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/APValue.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/lib/AST/APValue.cpp (original)
>> +++ cfe/trunk/lib/AST/APValue.cpp Thu May 16 18:46:05 2019
>> @@ -20,6 +20,56 @@
>> #include "llvm/Support/raw_ostream.h"
>> using namespace clang;
>>
>> +/// The identity of a type_info object depends on the canonical unqualified
>> +/// type only.
>> +TypeInfoLValue::TypeInfoLValue(const Type *T)
>> + : T(T->getCanonicalTypeUnqualified().getTypePtr()) {}
>> +
>> +void TypeInfoLValue::print(llvm::raw_ostream &Out,
>> + const PrintingPolicy &Policy) const {
>> + Out << "typeid(";
>> + QualType(getType(), 0).print(Out, Policy);
>> + Out << ")";
>> +}
>> +
>> +static_assert(
>> + 1 << llvm::PointerLikeTypeTraits<TypeInfoLValue>::NumLowBitsAvailable <=
>> + alignof(const Type *),
>> + "Type is insufficiently aligned");
>> +
>> +APValue::LValueBase APValue::LValueBase::getTypeInfo(TypeInfoLValue LV,
>> + QualType TypeInfo) {
>> + LValueBase Base;
>> + Base.Ptr = LV;
>> + Base.TypeInfoType = TypeInfo.getAsOpaquePtr();
>> + return Base;
>> +}
>> +
>> +unsigned APValue::LValueBase::getCallIndex() const {
>> + return is<TypeInfoLValue>() ? 0 : Local.CallIndex;
>> +}
>> +
>> +unsigned APValue::LValueBase::getVersion() const {
>> + return is<TypeInfoLValue>() ? 0 : Local.Version;
>> +}
>> +
>> +QualType APValue::LValueBase::getTypeInfoType() const {
>> + assert(is<TypeInfoLValue>() && "not a type_info lvalue");
>> + return QualType::getFromOpaquePtr(TypeInfoType);
>> +}
>> +
>> +namespace clang {
>> +bool operator==(const APValue::LValueBase &LHS,
>> + const APValue::LValueBase &RHS) {
>> + if (LHS.Ptr != RHS.Ptr)
>> + return false;
>> + if (LHS.is<TypeInfoLValue>())
>> + return true;
>> + return LHS.Local.CallIndex == RHS.Local.CallIndex &&
>> + LHS.Local.Version == RHS.Local.Version;
>> +}
>> +}
>> +
>> namespace {
>> struct LVBase {
>> APValue::LValueBase Base;
>> @@ -60,6 +110,8 @@ llvm::DenseMapInfo<clang::APValue::LValu
>>
>> namespace clang {
>> llvm::hash_code hash_value(const APValue::LValueBase &Base) {
>> + if (Base.is<TypeInfoLValue>())
>> + return llvm::hash_value(Base.getOpaqueValue());
>> return llvm::hash_combine(Base.getOpaqueValue(), Base.getCallIndex(),
>> Base.getVersion());
>> }
>> @@ -470,7 +522,9 @@ void APValue::printPretty(raw_ostream &O
>>
>> if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
>> Out << *VD;
>> - else {
>> + else if (TypeInfoLValue TI = Base.dyn_cast<TypeInfoLValue>()) {
>> + TI.print(Out, Ctx.getPrintingPolicy());
>> + } else {
>> assert(Base.get<const Expr *>() != nullptr &&
>> "Expecting non-null Expr");
>> Base.get<const Expr*>()->printPretty(Out, nullptr,
>> @@ -495,6 +549,9 @@ void APValue::printPretty(raw_ostream &O
>> if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
>> Out << *VD;
>> ElemTy = VD->getType();
>> + } else if (TypeInfoLValue TI = Base.dyn_cast<TypeInfoLValue>()) {
>> + TI.print(Out, Ctx.getPrintingPolicy());
>> + ElemTy = Base.getTypeInfoType();
>> } else {
>> const Expr *E = Base.get<const Expr*>();
>> assert(E != nullptr && "Expecting non-null Expr");
>>
>> Modified: cfe/trunk/lib/AST/ExprConstant.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/lib/AST/ExprConstant.cpp (original)
>> +++ cfe/trunk/lib/AST/ExprConstant.cpp Thu May 16 18:46:05 2019
>> @@ -87,6 +87,9 @@ namespace {
>> return D->getType();
>> }
>>
>> + if (TypeInfoLValue TI = B.dyn_cast<TypeInfoLValue>())
>> + return B.getTypeInfoType();
>> +
>> const Expr *Base = B.get<const Expr*>();
>>
>> // For a materialized temporary, the type of the temporary we materialized
>> @@ -1783,6 +1786,9 @@ static bool IsGlobalLValue(APValue::LVal
>> return isa<FunctionDecl>(D);
>> }
>>
>> + if (B.is<TypeInfoLValue>())
>> + return true;
>> +
>> const Expr *E = B.get<const Expr*>();
>> switch (E->getStmtClass()) {
>> default:
>> @@ -1800,7 +1806,6 @@ static bool IsGlobalLValue(APValue::LVal
>> case Expr::PredefinedExprClass:
>> case Expr::ObjCStringLiteralClass:
>> case Expr::ObjCEncodeExprClass:
>> - case Expr::CXXTypeidExprClass:
>> case Expr::CXXUuidofExprClass:
>> return true;
>> case Expr::ObjCBoxedExprClass:
>> @@ -1878,9 +1883,9 @@ static void NoteLValueLocation(EvalInfo
>> const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
>> if (VD)
>> Info.Note(VD->getLocation(), diag::note_declared_at);
>> - else
>> - Info.Note(Base.get<const Expr*>()->getExprLoc(),
>> - diag::note_constexpr_temporary_here);
>> + else if (const Expr *E = Base.dyn_cast<const Expr*>())
>> + Info.Note(E->getExprLoc(), diag::note_constexpr_temporary_here);
>> + // We have no information to show for a typeid(T) object.
>> }
>>
>> /// Check that this reference or pointer core constant expression is a valid
>> @@ -3404,7 +3409,7 @@ static CompleteObject findCompleteObject
>>
>> if (!Frame) {
>> if (const MaterializeTemporaryExpr *MTE =
>> - dyn_cast<MaterializeTemporaryExpr>(Base)) {
>> + dyn_cast_or_null<MaterializeTemporaryExpr>(Base)) {
>> assert(MTE->getStorageDuration() == SD_Static &&
>> "should have a frame for a non-global materialized temporary");
>>
>> @@ -3439,7 +3444,13 @@ static CompleteObject findCompleteObject
>> } else {
>> if (!IsAccess)
>> return CompleteObject(LVal.getLValueBase(), nullptr, BaseType);
>> - Info.FFDiag(E);
>> + APValue Val;
>> + LVal.moveInto(Val);
>> + Info.FFDiag(E, diag::note_constexpr_access_unreadable_object)
>> + << AK
>> + << Val.getAsString(Info.Ctx,
>> + Info.Ctx.getLValueReferenceType(LValType));
>> + NoteLValueLocation(Info, LVal.Base);
>> return CompleteObject();
>> }
>> } else {
>> @@ -5777,13 +5788,13 @@ public:
>> // - Literals
>> // * CompoundLiteralExpr in C (and in global scope in C++)
>> // * StringLiteral
>> -// * CXXTypeidExpr
>> // * PredefinedExpr
>> // * ObjCStringLiteralExpr
>> // * ObjCEncodeExpr
>> // * AddrLabelExpr
>> // * BlockExpr
>> // * CallExpr for a MakeStringConstant builtin
>> +// - typeid(T) expressions, as TypeInfoLValues
>> // - Locals and temporaries
>> // * MaterializeTemporaryExpr
>> // * Any Expr, with a CallIndex indicating the function in which the temporary
>> @@ -6018,8 +6029,14 @@ LValueExprEvaluator::VisitCompoundLitera
>> }
>>
>> bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) {
>> - if (!E->isPotentiallyEvaluated())
>> - return Success(E);
>> + if (!E->isPotentiallyEvaluated()) {
>> + TypeInfoLValue TypeInfo;
>> + if (E->isTypeOperand())
>> + TypeInfo = TypeInfoLValue(E->getTypeOperand(Info.Ctx).getTypePtr());
>> + else
>> + TypeInfo = TypeInfoLValue(E->getExprOperand()->getType().getTypePtr());
>> + return Success(APValue::LValueBase::getTypeInfo(TypeInfo, E->getType()));
>> + }
>>
>> Info.FFDiag(E, diag::note_constexpr_typeid_polymorphic)
>> << E->getExprOperand()->getType()
>> @@ -6615,9 +6632,11 @@ bool PointerExprEvaluator::VisitBuiltinC
>> if (const ValueDecl *VD =
>> OffsetResult.Base.dyn_cast<const ValueDecl*>()) {
>> BaseAlignment = Info.Ctx.getDeclAlign(VD);
>> + } else if (const Expr *E = OffsetResult.Base.dyn_cast<const Expr *>()) {
>> + BaseAlignment = GetAlignOfExpr(Info, E, UETT_AlignOf);
>> } else {
>> - BaseAlignment = GetAlignOfExpr(
>> - Info, OffsetResult.Base.get<const Expr *>(), UETT_AlignOf);
>> + BaseAlignment = GetAlignOfType(
>> + Info, OffsetResult.Base.getTypeInfoType(), UETT_AlignOf);
>> }
>>
>> if (BaseAlignment < Align) {
>> @@ -8335,6 +8354,10 @@ static bool EvaluateBuiltinConstantPForL
>> if (!isa<StringLiteral>(E))
>> return false;
>> return LV.getLValueOffset().isZero();
>> + } else if (Base.is<TypeInfoLValue>()) {
>> + // Surprisingly, GCC considers __builtin_constant_p(&typeid(int)) to
>> + // evaluate to true.
>> + return true;
>> } else {
>> // Any other base is not constant enough for GCC.
>> return false;
>> @@ -8399,6 +8422,8 @@ static QualType getObjectType(APValue::L
>> } else if (const Expr *E = B.get<const Expr*>()) {
>> if (isa<CompoundLiteralExpr>(E))
>> return E->getType();
>> + } else if (B.is<TypeInfoLValue>()) {
>> + return B.getTypeInfoType();
>> }
>>
>> return QualType();
>>
>> Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprConstant.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/lib/CodeGen/CGExprConstant.cpp (original)
>> +++ cfe/trunk/lib/CodeGen/CGExprConstant.cpp Thu May 16 18:46:05 2019
>> @@ -1735,6 +1735,17 @@ ConstantLValueEmitter::tryEmitBase(const
>> return nullptr;
>> }
>>
>> + // Handle typeid(T).
>> + if (TypeInfoLValue TI = base.dyn_cast<TypeInfoLValue>()) {
>> + llvm::Type *StdTypeInfoPtrTy =
>> + CGM.getTypes().ConvertType(base.getTypeInfoType())->getPointerTo();
>> + llvm::Constant *TypeInfo =
>> + CGM.GetAddrOfRTTIDescriptor(QualType(TI.getType(), 0));
>> + if (TypeInfo->getType() != StdTypeInfoPtrTy)
>> + TypeInfo = llvm::ConstantExpr::getBitCast(TypeInfo, StdTypeInfoPtrTy);
>> + return TypeInfo;
>> + }
>> +
>> // Otherwise, it must be an expression.
>> return Visit(base.get<const Expr*>());
>> }
>>
>> Modified: cfe/trunk/lib/Sema/SemaTemplate.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplate.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/lib/Sema/SemaTemplate.cpp (original)
>> +++ cfe/trunk/lib/Sema/SemaTemplate.cpp Thu May 16 18:46:05 2019
>> @@ -6424,8 +6424,11 @@ ExprResult Sema::CheckTemplateArgument(N
>> // -- a string literal
>> // -- the result of a typeid expression, or
>> // -- a predefined __func__ variable
>> - if (auto *E = Value.getLValueBase().dyn_cast<const Expr*>()) {
>> - if (isa<CXXUuidofExpr>(E)) {
>> + APValue::LValueBase Base = Value.getLValueBase();
>> + auto *VD = const_cast<ValueDecl *>(Base.dyn_cast<const ValueDecl *>());
>> + if (Base && !VD) {
>> + auto *E = Base.dyn_cast<const Expr *>();
>> + if (E && isa<CXXUuidofExpr>(E)) {
>> Converted = TemplateArgument(ArgResult.get()->IgnoreImpCasts());
>> break;
>> }
>> @@ -6433,8 +6436,6 @@ ExprResult Sema::CheckTemplateArgument(N
>> << 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() &&
>>
>> Modified: cfe/trunk/test/CXX/drs/dr19xx.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CXX/drs/dr19xx.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/test/CXX/drs/dr19xx.cpp (original)
>> +++ cfe/trunk/test/CXX/drs/dr19xx.cpp Thu May 16 18:46:05 2019
>> @@ -167,9 +167,14 @@ namespace dr1959 { // dr1959: 3.9
>> #endif
>> }
>>
>> -namespace dr1968 { // dr1968: yes
>> +namespace dr1968 { // dr1968: no
>> #if __cplusplus >= 201103L
>> - static_assert(&typeid(int) == &typeid(int), ""); // expected-error{{not an integral constant expression}}
>> + // FIXME: According to DR1968, both of these should be considered
>> + // non-constant.
>> + static_assert(&typeid(int) == &typeid(int), "");
>> +
>> + constexpr const std::type_info *f() { return &typeid(int); }
>> + static_assert(f() == f(), "");
>> #endif
>> }
>>
>>
>> Modified: cfe/trunk/test/Parser/MicrosoftExtensions.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Parser/MicrosoftExtensions.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/test/Parser/MicrosoftExtensions.cpp (original)
>> +++ cfe/trunk/test/Parser/MicrosoftExtensions.cpp Thu May 16 18:46:05 2019
>> @@ -138,6 +138,8 @@ typedef COM_CLASS_TEMPLATE_REF<struct_wi
>> COM_CLASS_TEMPLATE_REF<int, __uuidof(struct_with_uuid)> good_template_arg;
>>
>> COM_CLASS_TEMPLATE<int, __uuidof(struct_with_uuid)> bad_template_arg; // expected-error {{non-type template argument of type 'const _GUID' is not a constant expression}}
>> +// expected-note at -1 {{read of object '__uuidof(struct_with_uuid)' whose value is not known}}
>> +// expected-note at -2 {{temporary created here}}
>>
>> namespace PR16911 {
>> struct __declspec(uuid("{12345678-1234-1234-1234-1234567890aB}")) uuid;
>>
>> Modified: cfe/trunk/test/SemaCXX/builtin-constant-p.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/builtin-constant-p.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/test/SemaCXX/builtin-constant-p.cpp (original)
>> +++ cfe/trunk/test/SemaCXX/builtin-constant-p.cpp Thu May 16 18:46:05 2019
>> @@ -130,3 +130,8 @@ constexpr int mutate6(bool mutate) {
>> static_assert(mutate6(false) == 11);
>> // Mutation of state outside __builtin_constant_p: evaluates to false.
>> static_assert(mutate6(true) == 10);
>> +
>> +// GCC strangely returns true for the address of a type_info object, despite it
>> +// not being a pointer to the start of a string literal.
>> +namespace std { struct type_info; }
>> +static_assert(__builtin_constant_p(&typeid(int)));
>>
>> Modified: cfe/trunk/test/SemaCXX/typeid.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/typeid.cpp?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/test/SemaCXX/typeid.cpp (original)
>> +++ cfe/trunk/test/SemaCXX/typeid.cpp Thu May 16 18:46:05 2019
>> @@ -6,7 +6,7 @@ void f()
>> }
>>
>> namespace std {
>> - class type_info;
>> + struct type_info { const char *name; };
>> }
>>
>> void g()
>> @@ -27,3 +27,6 @@ void h(int i) {
>> typeid(V); // expected-error{{'typeid' of variably modified type 'char [i]'}}
>> typeid(char [i]); // expected-error{{'typeid' of variably modified type 'char [i]'}}
>> }
>> +
>> +// expected-note at +1 {{read of object 'typeid(int).name' whose value is not known}}
>> +constexpr const char *name = typeid(int).name; // expected-error {{constant expression}}
>>
>> Modified: cfe/trunk/www/cxx_dr_status.html
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/www/cxx_dr_status.html?rev=360974&r1=360973&r2=360974&view=diff
>> ==============================================================================
>> --- cfe/trunk/www/cxx_dr_status.html (original)
>> +++ cfe/trunk/www/cxx_dr_status.html Thu May 16 18:46:05 2019
>> @@ -11623,7 +11623,7 @@ and <I>POD class</I></td>
>> <td><a href="http://wg21.link/cwg1968">1968</a></td>
>> <td>NAD</td>
>> <td>Address of <TT>typeid</TT> in constant expressions</td>
>> - <td class="full" align="center">Yes</td>
>> + <td class="none" align="center">No</td>
>> </tr>
>> <tr class="open" id="1969">
>> <td><a href="http://wg21.link/cwg1969">1969</a></td>
>>
>>
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