Properly compute triviality for explicitly-defaulted or deleted special members.
Remove pre-standard restriction on explicitly-defaulted copy constructors with
'incorrect' parameter types, and instead just make those special members
non-trivial as the standard requires.
This required making CXXRecordDecl correctly handle classes which have both a
trivial and a non-trivial special member of the same kind.
This also fixes PR13217 by reimplementing DiagnoseNontrivial in terms of the
new triviality computation technology.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169667 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 3c31d41..538dcee 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -1658,13 +1658,6 @@
Parent->markedVirtualFunctionPure();
}
-void FunctionDecl::setConstexpr(bool IC) {
- IsConstexpr = IC;
- CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(this);
- if (IC && CD)
- CD->getParent()->markedConstructorConstexpr(CD);
-}
-
bool FunctionDecl::isMain() const {
const TranslationUnitDecl *tunit =
dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
diff --git a/lib/AST/DeclCXX.cpp b/lib/AST/DeclCXX.cpp
index d3a0c1a..dfcc154 100644
--- a/lib/AST/DeclCXX.cpp
+++ b/lib/AST/DeclCXX.cpp
@@ -43,6 +43,7 @@
HasMutableFields(false), HasOnlyCMembers(true),
HasInClassInitializer(false), HasUninitializedReferenceMember(false),
HasTrivialSpecialMembers(SMF_All),
+ DeclaredNonTrivialSpecialMembers(0),
HasIrrelevantDestructor(true),
HasConstexprNonCopyMoveConstructor(false),
DefaultedDefaultConstructorIsConstexpr(true),
@@ -261,7 +262,7 @@
if (!BaseClassDecl->hasConstexprDefaultConstructor())
data().DefaultedDefaultConstructorIsConstexpr = false;
}
-
+
// C++ [class.ctor]p3:
// A destructor is trivial if all the direct base classes of its class
// have trivial destructors.
@@ -470,14 +471,6 @@
data().Abstract = true;
}
-void CXXRecordDecl::markedConstructorConstexpr(CXXConstructorDecl *CD) {
- if (!CD->isCopyOrMoveConstructor())
- data().HasConstexprNonCopyMoveConstructor = true;
-
- if (CD->isDefaultConstructor())
- data().HasConstexprDefaultConstructor = true;
-}
-
void CXXRecordDecl::addedMember(Decl *D) {
if (!D->isImplicit() &&
!isa<FieldDecl>(D) &&
@@ -638,6 +631,20 @@
}
if (SMKind) {
+ // If this is the first declaration of a special member, we no longer have
+ // an implicit trivial special member.
+ data().HasTrivialSpecialMembers &=
+ data().DeclaredSpecialMembers | ~SMKind;
+
+ if (!Method->isImplicit() && !Method->isUserProvided()) {
+ // This method is user-declared but not user-provided. We can't work out
+ // whether it's trivial yet (not until we get to the end of the class).
+ // We'll handle this method in finishedDefaultedOrDeletedMember.
+ } else if (Method->isTrivial())
+ data().HasTrivialSpecialMembers |= SMKind;
+ else
+ data().DeclaredNonTrivialSpecialMembers |= SMKind;
+
// Note when we have declared a declared special member, and suppress the
// implicit declaration of this special member.
data().DeclaredSpecialMembers |= SMKind;
@@ -658,14 +665,6 @@
// This is an extension in C++03.
data().PlainOldData = false;
}
-
- // C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25,
- // C++11 [class.dtor]p5:
- // A [special member] is trivial if it is not user-provided [...]
- // FIXME: This is bogus. A class can have both (say) a trivial copy
- // constructor *and* a user-provided copy constructor.
- if (Method->isUserProvided())
- data().HasTrivialSpecialMembers &= ~SMKind;
}
return;
@@ -910,6 +909,40 @@
data().Conversions.addDecl(getASTContext(), Shadow, Shadow->getAccess());
}
+void CXXRecordDecl::finishedDefaultedOrDeletedMember(CXXMethodDecl *D) {
+ assert(!D->isImplicit() && !D->isUserProvided());
+
+ // The kind of special member this declaration is, if any.
+ unsigned SMKind = 0;
+
+ if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
+ if (Constructor->isDefaultConstructor()) {
+ SMKind |= SMF_DefaultConstructor;
+ if (Constructor->isConstexpr())
+ data().HasConstexprDefaultConstructor = true;
+ }
+ if (Constructor->isCopyConstructor())
+ SMKind |= SMF_CopyConstructor;
+ else if (Constructor->isMoveConstructor())
+ SMKind |= SMF_MoveConstructor;
+ else if (Constructor->isConstexpr())
+ // We may now know that the constructor is constexpr.
+ data().HasConstexprNonCopyMoveConstructor = true;
+ } else if (isa<CXXDestructorDecl>(D))
+ SMKind |= SMF_Destructor;
+ else if (D->isCopyAssignmentOperator())
+ SMKind |= SMF_CopyAssignment;
+ else if (D->isMoveAssignmentOperator())
+ SMKind |= SMF_MoveAssignment;
+
+ // Update which trivial / non-trivial special members we have.
+ // addedMember will have skipped this step for this member.
+ if (D->isTrivial())
+ data().HasTrivialSpecialMembers |= SMKind;
+ else
+ data().DeclaredNonTrivialSpecialMembers |= SMKind;
+}
+
bool CXXRecordDecl::isCLike() const {
if (getTagKind() == TTK_Class || getTagKind() == TTK_Interface ||
!TemplateOrInstantiation.isNull())
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 502a855..be30053 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -9772,7 +9772,7 @@
QualType EltTy = Context.getBaseElementType(FD->getType());
if (const RecordType *RT = EltTy->getAs<RecordType>()) {
- CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
+ CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
if (RDecl->getDefinition()) {
// We check for copy constructors before constructors
// because otherwise we'll never get complaints about
@@ -9814,194 +9814,15 @@
diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
diag::err_illegal_union_or_anon_struct_member)
<< (int)FD->getParent()->isUnion() << FD->getDeclName() << member;
- DiagnoseNontrivial(RT, member);
+ DiagnoseNontrivial(RDecl, member);
return !getLangOpts().CPlusPlus0x;
}
}
}
-
+
return false;
}
-/// If the given constructor is user-declared, produce a diagnostic explaining
-/// that it makes the class non-trivial.
-static bool diagnoseNonTrivialUserDeclaredCtor(Sema &S, QualType QT,
- CXXConstructorDecl *CD,
- Sema::CXXSpecialMember CSM) {
- if (CD->isImplicit())
- return false;
-
- SourceLocation CtorLoc = CD->getLocation();
- S.Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << CSM;
- return true;
-}
-
-/// DiagnoseNontrivial - Given that a class has a non-trivial
-/// special member, figure out why.
-/// FIXME: These checks are not correct in C++11 mode. Currently, this is OK
-/// since we only use this in C++11 for a -Wc++98-compat warning.
-void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) {
- QualType QT(T, 0U);
- CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl());
-
- // Check whether the member was user-declared.
- switch (member) {
- case CXXInvalid:
- break;
-
- case CXXDefaultConstructor:
- if (RD->hasUserDeclaredConstructor()) {
- typedef CXXRecordDecl::ctor_iterator ctor_iter;
- for (ctor_iter CI = RD->ctor_begin(), CE = RD->ctor_end(); CI != CE; ++CI)
- if (diagnoseNonTrivialUserDeclaredCtor(*this, QT, *CI, member))
- return;
-
- // No user-delcared constructors; look for constructor templates.
- typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl>
- tmpl_iter;
- for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end());
- TI != TE; ++TI) {
- CXXConstructorDecl *CD =
- dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl());
- if (CD && diagnoseNonTrivialUserDeclaredCtor(*this, QT, CD, member))
- return;
- }
- }
- break;
-
- case CXXCopyConstructor:
- if (RD->hasUserDeclaredCopyConstructor()) {
- SourceLocation CtorLoc =
- RD->getCopyConstructor(0)->getLocation();
- Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member;
- return;
- }
- break;
-
- case CXXMoveConstructor:
- if (RD->hasUserDeclaredMoveConstructor()) {
- SourceLocation CtorLoc = RD->getMoveConstructor()->getLocation();
- Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member;
- return;
- }
- break;
-
- case CXXCopyAssignment:
- if (RD->hasUserDeclaredCopyAssignment()) {
- SourceLocation AssignLoc =
- RD->getCopyAssignmentOperator(0)->getLocation();
- Diag(AssignLoc, diag::note_nontrivial_user_defined) << QT << member;
- return;
- }
- break;
-
- case CXXMoveAssignment:
- if (RD->hasUserDeclaredMoveAssignment()) {
- SourceLocation AssignLoc = RD->getMoveAssignmentOperator()->getLocation();
- Diag(AssignLoc, diag::note_nontrivial_user_defined) << QT << member;
- return;
- }
- break;
-
- case CXXDestructor:
- if (RD->hasUserDeclaredDestructor()) {
- SourceLocation DtorLoc = LookupDestructor(RD)->getLocation();
- Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member;
- return;
- }
- break;
- }
-
- typedef CXXRecordDecl::base_class_iterator base_iter;
-
- // Virtual bases and members inhibit trivial copying/construction,
- // but not trivial destruction.
- if (member != CXXDestructor) {
- // Check for virtual bases. vbases includes indirect virtual bases,
- // so we just iterate through the direct bases.
- for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi)
- if (bi->isVirtual()) {
- SourceLocation BaseLoc = bi->getLocStart();
- Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1;
- return;
- }
-
- // Check for virtual methods.
- typedef CXXRecordDecl::method_iterator meth_iter;
- for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
- ++mi) {
- if (mi->isVirtual()) {
- SourceLocation MLoc = mi->getLocStart();
- Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0;
- return;
- }
- }
- }
-
- bool (CXXRecordDecl::*hasNonTrivial)() const;
- switch (member) {
- case CXXDefaultConstructor:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialDefaultConstructor; break;
- case CXXCopyConstructor:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialCopyConstructor; break;
- case CXXCopyAssignment:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialCopyAssignment; break;
- case CXXMoveConstructor:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialMoveConstructor; break;
- case CXXMoveAssignment:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialMoveAssignment; break;
- case CXXDestructor:
- hasNonTrivial = &CXXRecordDecl::hasNonTrivialDestructor; break;
- case CXXInvalid:
- llvm_unreachable("unexpected special member");
- }
-
- // Check for nontrivial bases (and recurse).
- for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) {
- const RecordType *BaseRT = bi->getType()->getAs<RecordType>();
- assert(BaseRT && "Don't know how to handle dependent bases");
- CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl());
- if ((BaseRecTy->*hasNonTrivial)()) {
- SourceLocation BaseLoc = bi->getLocStart();
- Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member;
- DiagnoseNontrivial(BaseRT, member);
- return;
- }
- }
-
- // Check for nontrivial members (and recurse).
- typedef RecordDecl::field_iterator field_iter;
- for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe;
- ++fi) {
- QualType EltTy = Context.getBaseElementType(fi->getType());
- if (const RecordType *EltRT = EltTy->getAs<RecordType>()) {
- CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl());
-
- if ((EltRD->*hasNonTrivial)()) {
- SourceLocation FLoc = fi->getLocation();
- Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member;
- DiagnoseNontrivial(EltRT, member);
- return;
- }
- }
-
- if (EltTy->isObjCLifetimeType()) {
- switch (EltTy.getObjCLifetime()) {
- case Qualifiers::OCL_None:
- case Qualifiers::OCL_ExplicitNone:
- break;
-
- case Qualifiers::OCL_Autoreleasing:
- case Qualifiers::OCL_Weak:
- case Qualifiers::OCL_Strong:
- Diag(fi->getLocation(), diag::note_nontrivial_objc_ownership)
- << QT << EltTy.getObjCLifetime();
- return;
- }
- }
- }
-}
-
/// TranslateIvarVisibility - Translate visibility from a token ID to an
/// AST enum value.
static ObjCIvarDecl::AccessControl
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 88cc0aa..f4b9a92 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -3990,42 +3990,6 @@
}
}
- // C++0x [dcl.constexpr]p8: A constexpr specifier for a non-static member
- // function that is not a constructor declares that member function to be
- // const. [...] The class of which that function is a member shall be
- // a literal type.
- //
- // If the class has virtual bases, any constexpr members will already have
- // been diagnosed by the checks performed on the member declaration, so
- // suppress this (less useful) diagnostic.
- if (LangOpts.CPlusPlus0x && !Record->isDependentType() &&
- !Record->isLiteral() && !Record->getNumVBases()) {
- for (CXXRecordDecl::method_iterator M = Record->method_begin(),
- MEnd = Record->method_end();
- M != MEnd; ++M) {
- if (M->isConstexpr() && M->isInstance() && !isa<CXXConstructorDecl>(*M)) {
- switch (Record->getTemplateSpecializationKind()) {
- case TSK_ImplicitInstantiation:
- case TSK_ExplicitInstantiationDeclaration:
- case TSK_ExplicitInstantiationDefinition:
- // If a template instantiates to a non-literal type, but its members
- // instantiate to constexpr functions, the template is technically
- // ill-formed, but we allow it for sanity.
- continue;
-
- case TSK_Undeclared:
- case TSK_ExplicitSpecialization:
- RequireLiteralType(M->getLocation(), Context.getRecordType(Record),
- diag::err_constexpr_method_non_literal);
- break;
- }
-
- // Only produce one error per class.
- break;
- }
- }
- }
-
// Declare inherited constructors. We do this eagerly here because:
// - The standard requires an eager diagnostic for conflicting inherited
// constructors from different classes.
@@ -4036,12 +4000,25 @@
DeclareInheritedConstructors(Record);
}
-void Sema::CheckExplicitlyDefaultedMethods(CXXRecordDecl *Record) {
+void Sema::CheckExplicitlyDefaultedAndDeletedMethods(CXXRecordDecl *Record) {
for (CXXRecordDecl::method_iterator MI = Record->method_begin(),
ME = Record->method_end();
- MI != ME; ++MI)
+ MI != ME; ++MI) {
if (!MI->isInvalidDecl() && MI->isExplicitlyDefaulted())
CheckExplicitlyDefaultedSpecialMember(*MI);
+
+ if (!MI->isImplicit() && !MI->isUserProvided()) {
+ // For an explicitly defaulted or deleted special member, we defer
+ // determining triviality until the class is complete. That time is now!
+ CXXSpecialMember CSM = getSpecialMember(*MI);
+ if (CSM != CXXInvalid) {
+ MI->setTrivial(SpecialMemberIsTrivial(*MI, CSM));
+
+ // Inform the class that we've finished declaring this member.
+ Record->finishedDefaultedOrDeletedMember(*MI);
+ }
+ }
+ }
}
/// Is the special member function which would be selected to perform the
@@ -4231,33 +4208,11 @@
const FunctionProtoType *Type = MD->getType()->getAs<FunctionProtoType>();
- // Compute argument constness, constexpr, and triviality.
bool CanHaveConstParam = false;
- bool Trivial = false;
- switch (CSM) {
- case CXXDefaultConstructor:
- Trivial = RD->hasTrivialDefaultConstructor();
- break;
- case CXXCopyConstructor:
+ if (CSM == CXXCopyConstructor)
CanHaveConstParam = RD->implicitCopyConstructorHasConstParam();
- Trivial = RD->hasTrivialCopyConstructor();
- break;
- case CXXCopyAssignment:
+ else if (CSM == CXXCopyAssignment)
CanHaveConstParam = RD->implicitCopyAssignmentHasConstParam();
- Trivial = RD->hasTrivialCopyAssignment();
- break;
- case CXXMoveConstructor:
- Trivial = RD->hasTrivialMoveConstructor();
- break;
- case CXXMoveAssignment:
- Trivial = RD->hasTrivialMoveAssignment();
- break;
- case CXXDestructor:
- Trivial = RD->hasTrivialDestructor();
- break;
- case CXXInvalid:
- llvm_unreachable("non-special member explicitly defaulted!");
- }
QualType ReturnType = Context.VoidTy;
if (CSM == CXXCopyAssignment || CSM == CXXMoveAssignment) {
@@ -4306,14 +4261,6 @@
}
HadError = true;
}
-
- // If a function is explicitly defaulted on its first declaration, it shall
- // have the same parameter type as if it had been implicitly declared.
- // (Presumably this is to prevent it from being trivial?)
- if (!HasConstParam && CanHaveConstParam && First)
- Diag(MD->getLocation(),
- diag::err_defaulted_special_member_copy_non_const_param)
- << (CSM == CXXCopyAssignment);
} else if (ExpectedParams) {
// A copy assignment operator can take its argument by value, but a
// defaulted one cannot.
@@ -4363,10 +4310,6 @@
// -- it is implicitly considered to have the same exception-specification
// as if it had been implicitly declared,
MD->setType(QualType(ImplicitType, 0));
-
- // Such a function is also trivial if the implicitly-declared function
- // would have been.
- MD->setTrivial(Trivial);
}
if (ShouldDeleteSpecialMember(MD, CSM)) {
@@ -4805,6 +4748,427 @@
return false;
}
+/// Perform lookup for a special member of the specified kind, and determine
+/// whether it is trivial. If the triviality can be determined without the
+/// lookup, skip it. This is intended for use when determining whether a
+/// special member of a containing object is trivial, and thus does not ever
+/// perform overload resolution for default constructors.
+///
+/// If \p Selected is not \c NULL, \c *Selected will be filled in with the
+/// member that was most likely to be intended to be trivial, if any.
+static bool findTrivialSpecialMember(Sema &S, CXXRecordDecl *RD,
+ Sema::CXXSpecialMember CSM, unsigned Quals,
+ CXXMethodDecl **Selected) {
+ if (Selected)
+ *Selected = 0;
+
+ switch (CSM) {
+ case Sema::CXXInvalid:
+ llvm_unreachable("not a special member");
+
+ case Sema::CXXDefaultConstructor:
+ // C++11 [class.ctor]p5:
+ // A default constructor is trivial if:
+ // - all the [direct subobjects] have trivial default constructors
+ //
+ // Note, no overload resolution is performed in this case.
+ if (RD->hasTrivialDefaultConstructor())
+ return true;
+
+ if (Selected) {
+ // If there's a default constructor which could have been trivial, dig it
+ // out. Otherwise, if there's any user-provided default constructor, point
+ // to that as an example of why there's not a trivial one.
+ CXXConstructorDecl *DefCtor = 0;
+ if (RD->needsImplicitDefaultConstructor())
+ S.DeclareImplicitDefaultConstructor(RD);
+ for (CXXRecordDecl::ctor_iterator CI = RD->ctor_begin(),
+ CE = RD->ctor_end(); CI != CE; ++CI) {
+ if (!CI->isDefaultConstructor())
+ continue;
+ DefCtor = *CI;
+ if (!DefCtor->isUserProvided())
+ break;
+ }
+
+ *Selected = DefCtor;
+ }
+
+ return false;
+
+ case Sema::CXXDestructor:
+ // C++11 [class.dtor]p5:
+ // A destructor is trivial if:
+ // - all the direct [subobjects] have trivial destructors
+ if (RD->hasTrivialDestructor())
+ return true;
+
+ if (Selected) {
+ if (RD->needsImplicitDestructor())
+ S.DeclareImplicitDestructor(RD);
+ *Selected = RD->getDestructor();
+ }
+
+ return false;
+
+ case Sema::CXXCopyConstructor:
+ // C++11 [class.copy]p12:
+ // A copy constructor is trivial if:
+ // - the constructor selected to copy each direct [subobject] is trivial
+ if (RD->hasTrivialCopyConstructor()) {
+ if (Quals == Qualifiers::Const)
+ // We must either select the trivial copy constructor or reach an
+ // ambiguity; no need to actually perform overload resolution.
+ return true;
+ } else if (!Selected) {
+ return false;
+ }
+ // In C++98, we are not supposed to perform overload resolution here, but we
+ // treat that as a language defect, as suggested on cxx-abi-dev, to treat
+ // cases like B as having a non-trivial copy constructor:
+ // struct A { template<typename T> A(T&); };
+ // struct B { mutable A a; };
+ goto NeedOverloadResolution;
+
+ case Sema::CXXCopyAssignment:
+ // C++11 [class.copy]p25:
+ // A copy assignment operator is trivial if:
+ // - the assignment operator selected to copy each direct [subobject] is
+ // trivial
+ if (RD->hasTrivialCopyAssignment()) {
+ if (Quals == Qualifiers::Const)
+ return true;
+ } else if (!Selected) {
+ return false;
+ }
+ // In C++98, we are not supposed to perform overload resolution here, but we
+ // treat that as a language defect.
+ goto NeedOverloadResolution;
+
+ case Sema::CXXMoveConstructor:
+ case Sema::CXXMoveAssignment:
+ NeedOverloadResolution:
+ Sema::SpecialMemberOverloadResult *SMOR =
+ S.LookupSpecialMember(RD, CSM,
+ Quals & Qualifiers::Const,
+ Quals & Qualifiers::Volatile,
+ /*RValueThis*/false, /*ConstThis*/false,
+ /*VolatileThis*/false);
+
+ // The standard doesn't describe how to behave if the lookup is ambiguous.
+ // We treat it as not making the member non-trivial, just like the standard
+ // mandates for the default constructor. This should rarely matter, because
+ // the member will also be deleted.
+ if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
+ return true;
+
+ if (!SMOR->getMethod()) {
+ assert(SMOR->getKind() ==
+ Sema::SpecialMemberOverloadResult::NoMemberOrDeleted);
+ return false;
+ }
+
+ // We deliberately don't check if we found a deleted special member. We're
+ // not supposed to!
+ if (Selected)
+ *Selected = SMOR->getMethod();
+ return SMOR->getMethod()->isTrivial();
+ }
+
+ llvm_unreachable("unknown special method kind");
+}
+
+CXXConstructorDecl *findUserDeclaredCtor(CXXRecordDecl *RD) {
+ for (CXXRecordDecl::ctor_iterator CI = RD->ctor_begin(), CE = RD->ctor_end();
+ CI != CE; ++CI)
+ if (!CI->isImplicit())
+ return *CI;
+
+ // Look for constructor templates.
+ typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl> tmpl_iter;
+ for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end()); TI != TE; ++TI) {
+ if (CXXConstructorDecl *CD =
+ dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl()))
+ return CD;
+ }
+
+ return 0;
+}
+
+/// The kind of subobject we are checking for triviality. The values of this
+/// enumeration are used in diagnostics.
+enum TrivialSubobjectKind {
+ /// The subobject is a base class.
+ TSK_BaseClass,
+ /// The subobject is a non-static data member.
+ TSK_Field,
+ /// The object is actually the complete object.
+ TSK_CompleteObject
+};
+
+/// Check whether the special member selected for a given type would be trivial.
+static bool checkTrivialSubobjectCall(Sema &S, SourceLocation SubobjLoc,
+ QualType SubType,
+ Sema::CXXSpecialMember CSM,
+ TrivialSubobjectKind Kind,
+ bool Diagnose) {
+ CXXRecordDecl *SubRD = SubType->getAsCXXRecordDecl();
+ if (!SubRD)
+ return true;
+
+ CXXMethodDecl *Selected;
+ if (findTrivialSpecialMember(S, SubRD, CSM, SubType.getCVRQualifiers(),
+ Diagnose ? &Selected : 0))
+ return true;
+
+ if (Diagnose) {
+ if (!Selected && CSM == Sema::CXXDefaultConstructor) {
+ S.Diag(SubobjLoc, diag::note_nontrivial_no_def_ctor)
+ << Kind << SubType.getUnqualifiedType();
+ if (CXXConstructorDecl *CD = findUserDeclaredCtor(SubRD))
+ S.Diag(CD->getLocation(), diag::note_user_declared_ctor);
+ } else if (!Selected)
+ S.Diag(SubobjLoc, diag::note_nontrivial_no_copy)
+ << Kind << SubType.getUnqualifiedType() << CSM << SubType;
+ else if (Selected->isUserProvided()) {
+ if (Kind == TSK_CompleteObject)
+ S.Diag(Selected->getLocation(), diag::note_nontrivial_user_provided)
+ << Kind << SubType.getUnqualifiedType() << CSM;
+ else {
+ S.Diag(SubobjLoc, diag::note_nontrivial_user_provided)
+ << Kind << SubType.getUnqualifiedType() << CSM;
+ S.Diag(Selected->getLocation(), diag::note_declared_at);
+ }
+ } else {
+ if (Kind != TSK_CompleteObject)
+ S.Diag(SubobjLoc, diag::note_nontrivial_subobject)
+ << Kind << SubType.getUnqualifiedType() << CSM;
+
+ // Explain why the defaulted or deleted special member isn't trivial.
+ S.SpecialMemberIsTrivial(Selected, CSM, Diagnose);
+ }
+ }
+
+ return false;
+}
+
+/// Check whether the members of a class type allow a special member to be
+/// trivial.
+static bool checkTrivialClassMembers(Sema &S, CXXRecordDecl *RD,
+ Sema::CXXSpecialMember CSM,
+ bool ConstArg, bool Diagnose) {
+ for (CXXRecordDecl::field_iterator FI = RD->field_begin(),
+ FE = RD->field_end(); FI != FE; ++FI) {
+ if (FI->isInvalidDecl() || FI->isUnnamedBitfield())
+ continue;
+
+ QualType FieldType = S.Context.getBaseElementType(FI->getType());
+
+ // Pretend anonymous struct or union members are members of this class.
+ if (FI->isAnonymousStructOrUnion()) {
+ if (!checkTrivialClassMembers(S, FieldType->getAsCXXRecordDecl(),
+ CSM, ConstArg, Diagnose))
+ return false;
+ continue;
+ }
+
+ // C++11 [class.ctor]p5:
+ // A default constructor is trivial if [...]
+ // -- no non-static data member of its class has a
+ // brace-or-equal-initializer
+ if (CSM == Sema::CXXDefaultConstructor && FI->hasInClassInitializer()) {
+ if (Diagnose)
+ S.Diag(FI->getLocation(), diag::note_nontrivial_in_class_init) << *FI;
+ return false;
+ }
+
+ // Objective C ARC 4.3.5:
+ // [...] nontrivally ownership-qualified types are [...] not trivially
+ // default constructible, copy constructible, move constructible, copy
+ // assignable, move assignable, or destructible [...]
+ if (S.getLangOpts().ObjCAutoRefCount &&
+ FieldType.hasNonTrivialObjCLifetime()) {
+ if (Diagnose)
+ S.Diag(FI->getLocation(), diag::note_nontrivial_objc_ownership)
+ << RD << FieldType.getObjCLifetime();
+ return false;
+ }
+
+ if (ConstArg && !FI->isMutable())
+ FieldType.addConst();
+ if (!checkTrivialSubobjectCall(S, FI->getLocation(), FieldType, CSM,
+ TSK_Field, Diagnose))
+ return false;
+ }
+
+ return true;
+}
+
+/// Diagnose why the specified class does not have a trivial special member of
+/// the given kind.
+void Sema::DiagnoseNontrivial(const CXXRecordDecl *RD, CXXSpecialMember CSM) {
+ QualType Ty = Context.getRecordType(RD);
+ if (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)
+ Ty.addConst();
+
+ checkTrivialSubobjectCall(*this, RD->getLocation(), Ty, CSM,
+ TSK_CompleteObject, /*Diagnose*/true);
+}
+
+/// Determine whether a defaulted or deleted special member function is trivial,
+/// as specified in C++11 [class.ctor]p5, C++11 [class.copy]p12,
+/// C++11 [class.copy]p25, and C++11 [class.dtor]p5.
+bool Sema::SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
+ bool Diagnose) {
+ // Note that we can't work out CSM for ourselves. Consider this:
+ //
+ // struct S { S(int); S(const S&=0) = delete; };
+ //
+ // The same function is a trivial copy constructor but a non-trivial default
+ // constructor.
+ assert(!MD->isUserProvided() && CSM != CXXInvalid && "not special enough");
+
+ CXXRecordDecl *RD = MD->getParent();
+
+ bool ConstArg = false;
+ ParmVarDecl *Param0 = MD->getNumParams() ? MD->getParamDecl(0) : 0;
+
+ // C++11 [class.copy]p12, p25:
+ // A [special member] is trivial if its declared parameter type is the same
+ // as if it had been implicitly declared [...]
+ switch (CSM) {
+ case CXXDefaultConstructor:
+ case CXXDestructor:
+ // Trivial default constructors and destructors cannot have parameters.
+ break;
+
+ case CXXCopyConstructor:
+ case CXXCopyAssignment: {
+ // Trivial copy operations always have const, non-volatile parameter types.
+ ConstArg = true;
+ const ReferenceType *RT = Param0->getType()->getAs<ReferenceType>();
+ if (!RT || RT->getPointeeType().getCVRQualifiers() != Qualifiers::Const) {
+ if (Diagnose)
+ Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
+ << Param0->getSourceRange() << Param0->getType()
+ << Context.getLValueReferenceType(
+ Context.getRecordType(RD).withConst());
+ return false;
+ }
+ break;
+ }
+
+ case CXXMoveConstructor:
+ case CXXMoveAssignment: {
+ // Trivial move operations always have non-cv-qualified parameters.
+ const RValueReferenceType *RT =
+ Param0->getType()->getAs<RValueReferenceType>();
+ if (!RT || RT->getPointeeType().getCVRQualifiers()) {
+ if (Diagnose)
+ Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
+ << Param0->getSourceRange() << Param0->getType()
+ << Context.getRValueReferenceType(Context.getRecordType(RD));
+ return false;
+ }
+ break;
+ }
+
+ case CXXInvalid:
+ llvm_unreachable("not a special member");
+ }
+
+ // FIXME: We require that the parameter-declaration-clause is equivalent to
+ // that of an implicit declaration, not just that the declared parameter type
+ // matches, in order to prevent absuridities like a function simultaneously
+ // being a trivial copy constructor and a non-trivial default constructor.
+ // This issue has not yet been assigned a core issue number.
+ if (MD->getMinRequiredArguments() < MD->getNumParams()) {
+ if (Diagnose)
+ Diag(MD->getParamDecl(MD->getMinRequiredArguments())->getLocation(),
+ diag::note_nontrivial_default_arg)
+ << MD->getParamDecl(MD->getMinRequiredArguments())->getSourceRange();
+ return false;
+ }
+ if (MD->isVariadic()) {
+ if (Diagnose)
+ Diag(MD->getLocation(), diag::note_nontrivial_variadic);
+ return false;
+ }
+
+ // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
+ // A copy/move [constructor or assignment operator] is trivial if
+ // -- the [member] selected to copy/move each direct base class subobject
+ // is trivial
+ //
+ // C++11 [class.copy]p12, C++11 [class.copy]p25:
+ // A [default constructor or destructor] is trivial if
+ // -- all the direct base classes have trivial [default constructors or
+ // destructors]
+ for (CXXRecordDecl::base_class_iterator BI = RD->bases_begin(),
+ BE = RD->bases_end(); BI != BE; ++BI)
+ if (!checkTrivialSubobjectCall(*this, BI->getLocStart(),
+ ConstArg ? BI->getType().withConst()
+ : BI->getType(),
+ CSM, TSK_BaseClass, Diagnose))
+ return false;
+
+ // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
+ // A copy/move [constructor or assignment operator] for a class X is
+ // trivial if
+ // -- for each non-static data member of X that is of class type (or array
+ // thereof), the constructor selected to copy/move that member is
+ // trivial
+ //
+ // C++11 [class.copy]p12, C++11 [class.copy]p25:
+ // A [default constructor or destructor] is trivial if
+ // -- for all of the non-static data members of its class that are of class
+ // type (or array thereof), each such class has a trivial [default
+ // constructor or destructor]
+ if (!checkTrivialClassMembers(*this, RD, CSM, ConstArg, Diagnose))
+ return false;
+
+ // C++11 [class.dtor]p5:
+ // A destructor is trivial if [...]
+ // -- the destructor is not virtual
+ if (CSM == CXXDestructor && MD->isVirtual()) {
+ if (Diagnose)
+ Diag(MD->getLocation(), diag::note_nontrivial_virtual_dtor) << RD;
+ return false;
+ }
+
+ // C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25:
+ // A [special member] for class X is trivial if [...]
+ // -- class X has no virtual functions and no virtual base classes
+ if (CSM != CXXDestructor && MD->getParent()->isDynamicClass()) {
+ if (!Diagnose)
+ return false;
+
+ if (RD->getNumVBases()) {
+ // Check for virtual bases. We already know that the corresponding
+ // member in all bases is trivial, so vbases must all be direct.
+ CXXBaseSpecifier &BS = *RD->vbases_begin();
+ assert(BS.isVirtual());
+ Diag(BS.getLocStart(), diag::note_nontrivial_has_virtual) << RD << 1;
+ return false;
+ }
+
+ // Must have a virtual method.
+ for (CXXRecordDecl::method_iterator MI = RD->method_begin(),
+ ME = RD->method_end(); MI != ME; ++MI) {
+ if (MI->isVirtual()) {
+ SourceLocation MLoc = MI->getLocStart();
+ Diag(MLoc, diag::note_nontrivial_has_virtual) << RD << 0;
+ return false;
+ }
+ }
+
+ llvm_unreachable("dynamic class with no vbases and no virtual functions");
+ }
+
+ // Looks like it's trivial!
+ return true;
+}
+
/// \brief Data used with FindHiddenVirtualMethod
namespace {
struct FindHiddenVirtualMethodData {
@@ -7113,7 +7477,46 @@
CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(D);
if (!ClassDecl->isDependentType())
- CheckExplicitlyDefaultedMethods(ClassDecl);
+ CheckExplicitlyDefaultedAndDeletedMethods(ClassDecl);
+
+ // C++11 [dcl.constexpr]p8: A constexpr specifier for a non-static member
+ // function that is not a constructor declares that member function to be
+ // const. [...] The class of which that function is a member shall be
+ // a literal type.
+ //
+ // If the class has virtual bases, any constexpr members will already have
+ // been diagnosed by the checks performed on the member declaration, so
+ // suppress this (less useful) diagnostic.
+ //
+ // We delay this until we know whether an explicitly-defaulted (or deleted)
+ // destructor for the class is trivial.
+ if (LangOpts.CPlusPlus0x && !ClassDecl->isDependentType() &&
+ !ClassDecl->isLiteral() && !ClassDecl->getNumVBases()) {
+ for (CXXRecordDecl::method_iterator M = ClassDecl->method_begin(),
+ MEnd = ClassDecl->method_end();
+ M != MEnd; ++M) {
+ if (M->isConstexpr() && M->isInstance() && !isa<CXXConstructorDecl>(*M)) {
+ switch (ClassDecl->getTemplateSpecializationKind()) {
+ case TSK_ImplicitInstantiation:
+ case TSK_ExplicitInstantiationDeclaration:
+ case TSK_ExplicitInstantiationDefinition:
+ // If a template instantiates to a non-literal type, but its members
+ // instantiate to constexpr functions, the template is technically
+ // ill-formed, but we allow it for sanity.
+ continue;
+
+ case TSK_Undeclared:
+ case TSK_ExplicitSpecialization:
+ RequireLiteralType(M->getLocation(), Context.getRecordType(ClassDecl),
+ diag::err_constexpr_method_non_literal);
+ break;
+ }
+
+ // Only produce one error per class.
+ break;
+ }
+ }
+ }
}
void Sema::DeclareInheritedConstructors(CXXRecordDecl *ClassDecl) {
@@ -10395,35 +10798,6 @@
// recovery.
}
Fn->setDeletedAsWritten();
-
- CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Dcl);
- if (!MD)
- return;
-
- // A deleted special member function is trivial if the corresponding
- // implicitly-declared function would have been.
- switch (getSpecialMember(MD)) {
- case CXXInvalid:
- break;
- case CXXDefaultConstructor:
- MD->setTrivial(MD->getParent()->hasTrivialDefaultConstructor());
- break;
- case CXXCopyConstructor:
- MD->setTrivial(MD->getParent()->hasTrivialCopyConstructor());
- break;
- case CXXMoveConstructor:
- MD->setTrivial(MD->getParent()->hasTrivialMoveConstructor());
- break;
- case CXXCopyAssignment:
- MD->setTrivial(MD->getParent()->hasTrivialCopyAssignment());
- break;
- case CXXMoveAssignment:
- MD->setTrivial(MD->getParent()->hasTrivialMoveAssignment());
- break;
- case CXXDestructor:
- MD->setTrivial(MD->getParent()->hasTrivialDestructor());
- break;
- }
}
void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index b785e54..5345e8d 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -3058,6 +3058,13 @@
//
// 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
// 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
+ //
+ // Note that these builtins do not behave as documented in g++: if a class
+ // has both a trivial and a non-trivial special member of a particular kind,
+ // they return false! For now, we emulate this behavior.
+ // FIXME: This appears to be a g++ bug: more complex cases reveal that it
+ // does not correctly compute triviality in the presence of multiple special
+ // members of the same kind. Revisit this once the g++ bug is fixed.
case UTT_HasTrivialDefaultConstructor:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If __is_pod (type) is true then the trait is true, else if type is
@@ -3065,9 +3072,9 @@
// constructor ([class.ctor]) then the trait is true, else it is false.
if (T.isPODType(Self.Context))
return true;
- if (const RecordType *RT =
- C.getBaseElementType(T)->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDefaultConstructor();
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
+ return RD->hasTrivialDefaultConstructor() &&
+ !RD->hasNonTrivialDefaultConstructor();
return false;
case UTT_HasTrivialCopy:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3077,8 +3084,9 @@
// is true, else it is false.
if (T.isPODType(Self.Context) || T->isReferenceType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor();
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
+ return RD->hasTrivialCopyConstructor() &&
+ !RD->hasNonTrivialCopyConstructor();
return false;
case UTT_HasTrivialAssign:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3093,12 +3101,13 @@
// errors if the copy assignment operator is actually used, q.v.
// [class.copy]p12).
- if (C.getBaseElementType(T).isConstQualified())
+ if (T.isConstQualified())
return false;
if (T.isPODType(Self.Context))
return true;
- if (const RecordType *RT = T->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment();
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
+ return RD->hasTrivialCopyAssignment() &&
+ !RD->hasNonTrivialCopyAssignment();
return false;
case UTT_HasTrivialDestructor:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
@@ -3115,9 +3124,8 @@
T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
return true;
- if (const RecordType *RT =
- C.getBaseElementType(T)->getAs<RecordType>())
- return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor();
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
+ return RD->hasTrivialDestructor();
return false;
// TODO: Propagate nothrowness for implicitly declared special members.
case UTT_HasNothrowAssign:
@@ -3134,9 +3142,8 @@
return false;
if (T.isPODType(Self.Context) || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>()) {
- CXXRecordDecl* RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialCopyAssignment())
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialCopyAssignment() && !RD->hasNonTrivialCopyAssignment())
return true;
bool FoundAssign = false;
@@ -3175,9 +3182,9 @@
// false.
if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = T->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialCopyConstructor())
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialCopyConstructor() &&
+ !RD->hasNonTrivialCopyConstructor())
return true;
bool FoundConstructor = false;
@@ -3216,9 +3223,9 @@
// throw an exception then the trait is true, else it is false.
if (T.isPODType(C) || T->isObjCLifetimeType())
return true;
- if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
- if (RD->hasTrivialDefaultConstructor())
+ if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
+ if (RD->hasTrivialDefaultConstructor() &&
+ !RD->hasNonTrivialDefaultConstructor())
return true;
DeclContext::lookup_const_iterator Con, ConEnd;
@@ -3245,11 +3252,9 @@
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If type is a class type with a virtual destructor ([class.dtor])
// then the trait is true, else it is false.
- if (const RecordType *Record = T->getAs<RecordType>()) {
- CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
+ if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
return Destructor->isVirtual();
- }
return false;
// These type trait expressions are modeled on the specifications for the
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 2355544..337534e 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -1581,10 +1581,10 @@
SemaRef.CheckOverrideControl(Method);
// If a function is defined as defaulted or deleted, mark it as such now.
- if (D->isDefaulted())
- Method->setDefaulted();
+ if (D->isExplicitlyDefaulted())
+ SemaRef.SetDeclDefaulted(Method, Method->getLocation());
if (D->isDeletedAsWritten())
- Method->setDeletedAsWritten();
+ SemaRef.SetDeclDeleted(Method, Method->getLocation());
// If there's a function template, let our caller handle it.
if (FunctionTemplate) {
@@ -1610,13 +1610,6 @@
Owner->addDecl(Method);
}
- if (D->isExplicitlyDefaulted()) {
- SemaRef.SetDeclDefaulted(Method, Method->getLocation());
- } else {
- assert(!D->isDefaulted() &&
- "should not implicitly default uninstantiated function");
- }
-
return Method;
}
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 7b2973f..2c7b7c1 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -4564,6 +4564,8 @@
Diag(Dtor->getLocation(), Dtor->isUserProvided() ?
diag::note_non_literal_user_provided_dtor :
diag::note_non_literal_nontrivial_dtor) << RD;
+ if (!Dtor->isUserProvided())
+ SpecialMemberIsTrivial(Dtor, CXXDestructor, /*Diagnose*/true);
}
return true;