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//===--- Sema.h - Semantic Analysis & AST Building --------------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file defines the Sema class, which performs semantic analysis and
// builds ASTs.
#include "clang/AST/Attr.h"
#include "clang/AST/DeclarationName.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ExternalASTSource.h"
#include "clang/AST/MangleNumberingContext.h"
#include "clang/AST/NSAPI.h"
#include "clang/AST/PrettyPrinter.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/ExpressionTraits.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/Module.h"
#include "clang/Basic/OpenMPKinds.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TemplateKinds.h"
#include "clang/Basic/TypeTraits.h"
#include "clang/Sema/AnalysisBasedWarnings.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/ExternalSemaSource.h"
#include "clang/Sema/IdentifierResolver.h"
#include "clang/Sema/LocInfoType.h"
#include "clang/Sema/ObjCMethodList.h"
#include "clang/Sema/Ownership.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/TypoCorrection.h"
#include "clang/Sema/Weak.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/TinyPtrVector.h"
#include <deque>
#include <memory>
#include <string>
#include <vector>
namespace llvm {
class APSInt;
template <typename ValueT> struct DenseMapInfo;
template <typename ValueT, typename ValueInfoT> class DenseSet;
class SmallBitVector;
class InlineAsmIdentifierInfo;
namespace clang {
class ADLResult;
class ASTConsumer;
class ASTContext;
class ASTMutationListener;
class ASTReader;
class ASTWriter;
class ArrayType;
class AttributeList;
class BlockDecl;
class CapturedDecl;
class CXXBasePath;
class CXXBasePaths;
class CXXBindTemporaryExpr;
typedef SmallVector<CXXBaseSpecifier*, 4> CXXCastPath;
class CXXConstructorDecl;
class CXXConversionDecl;
class CXXDestructorDecl;
class CXXFieldCollector;
class CXXMemberCallExpr;
class CXXMethodDecl;
class CXXScopeSpec;
class CXXTemporary;
class CXXTryStmt;
class CallExpr;
class ClassTemplateDecl;
class ClassTemplatePartialSpecializationDecl;
class ClassTemplateSpecializationDecl;
class VarTemplatePartialSpecializationDecl;
class CodeCompleteConsumer;
class CodeCompletionAllocator;
class CodeCompletionTUInfo;
class CodeCompletionResult;
class Decl;
class DeclAccessPair;
class DeclContext;
class DeclRefExpr;
class DeclaratorDecl;
class DeducedTemplateArgument;
class DependentDiagnostic;
class DesignatedInitExpr;
class Designation;
class EnableIfAttr;
class EnumConstantDecl;
class Expr;
class ExtVectorType;
class ExternalSemaSource;
class FormatAttr;
class FriendDecl;
class FunctionDecl;
class FunctionProtoType;
class FunctionTemplateDecl;
class ImplicitConversionSequence;
class InitListExpr;
class InitializationKind;
class InitializationSequence;
class InitializedEntity;
class IntegerLiteral;
class LabelStmt;
class LambdaExpr;
class LangOptions;
class LocalInstantiationScope;
class LookupResult;
class MacroInfo;
typedef ArrayRef<std::pair<IdentifierInfo *, SourceLocation>> ModuleIdPath;
class ModuleLoader;
class MultiLevelTemplateArgumentList;
class NamedDecl;
class NonNullAttr;
class ObjCCategoryDecl;
class ObjCCategoryImplDecl;
class ObjCCompatibleAliasDecl;
class ObjCContainerDecl;
class ObjCImplDecl;
class ObjCImplementationDecl;
class ObjCInterfaceDecl;
class ObjCIvarDecl;
template <class T> class ObjCList;
class ObjCMessageExpr;
class ObjCMethodDecl;
class ObjCPropertyDecl;
class ObjCProtocolDecl;
class OMPThreadPrivateDecl;
class OMPClause;
class OverloadCandidateSet;
class OverloadExpr;
class ParenListExpr;
class ParmVarDecl;
class Preprocessor;
class PseudoDestructorTypeStorage;
class PseudoObjectExpr;
class QualType;
class StandardConversionSequence;
class Stmt;
class StringLiteral;
class SwitchStmt;
class TemplateArgument;
class TemplateArgumentList;
class TemplateArgumentLoc;
class TemplateDecl;
class TemplateParameterList;
class TemplatePartialOrderingContext;
class TemplateTemplateParmDecl;
class Token;
class TypeAliasDecl;
class TypedefDecl;
class TypedefNameDecl;
class TypeLoc;
class UnqualifiedId;
class UnresolvedLookupExpr;
class UnresolvedMemberExpr;
class UnresolvedSetImpl;
class UnresolvedSetIterator;
class UsingDecl;
class UsingShadowDecl;
class ValueDecl;
class VarDecl;
class VarTemplateSpecializationDecl;
class VisibilityAttr;
class VisibleDeclConsumer;
class IndirectFieldDecl;
struct DeductionFailureInfo;
class TemplateSpecCandidateSet;
namespace sema {
class AccessedEntity;
class BlockScopeInfo;
class CapturedRegionScopeInfo;
class CapturingScopeInfo;
class CompoundScopeInfo;
class DelayedDiagnostic;
class DelayedDiagnosticPool;
class FunctionScopeInfo;
class LambdaScopeInfo;
class PossiblyUnreachableDiag;
class TemplateDeductionInfo;
// FIXME: No way to easily map from TemplateTypeParmTypes to
// TemplateTypeParmDecls, so we have this horrible PointerUnion.
typedef std::pair<llvm::PointerUnion<const TemplateTypeParmType*, NamedDecl*>,
SourceLocation> UnexpandedParameterPack;
/// Sema - This implements semantic analysis and AST building for C.
class Sema {
void operator=(const Sema &) LLVM_DELETED_FUNCTION;
///\brief Source of additional semantic information.
ExternalSemaSource *ExternalSource;
///\brief Whether Sema has generated a multiplexer and has to delete it.
bool isMultiplexExternalSource;
static bool mightHaveNonExternalLinkage(const DeclaratorDecl *FD);
static bool
shouldLinkPossiblyHiddenDecl(const NamedDecl *Old, const NamedDecl *New) {
// We are about to link these. It is now safe to compute the linkage of
// the new decl. If the new decl has external linkage, we will
// link it with the hidden decl (which also has external linkage) and
// it will keep having external linkage. If it has internal linkage, we
// will not link it. Since it has no previous decls, it will remain
// with internal linkage.
return !Old->isHidden() || New->isExternallyVisible();
typedef OpaquePtr<DeclGroupRef> DeclGroupPtrTy;
typedef OpaquePtr<TemplateName> TemplateTy;
typedef OpaquePtr<QualType> TypeTy;
OpenCLOptions OpenCLFeatures;
FPOptions FPFeatures;
const LangOptions &LangOpts;
Preprocessor &PP;
ASTContext &Context;
ASTConsumer &Consumer;
DiagnosticsEngine &Diags;
SourceManager &SourceMgr;
/// \brief Flag indicating whether or not to collect detailed statistics.
bool CollectStats;
/// \brief Code-completion consumer.
CodeCompleteConsumer *CodeCompleter;
/// CurContext - This is the current declaration context of parsing.
DeclContext *CurContext;
/// \brief Generally null except when we temporarily switch decl contexts,
/// like in \see ActOnObjCTemporaryExitContainerContext.
DeclContext *OriginalLexicalContext;
/// VAListTagName - The declaration name corresponding to __va_list_tag.
/// This is used as part of a hack to omit that class from ADL results.
DeclarationName VAListTagName;
/// PackContext - Manages the stack for \#pragma pack. An alignment
/// of 0 indicates default alignment.
void *PackContext; // Really a "PragmaPackStack*"
bool MSStructPragmaOn; // True when \#pragma ms_struct on
/// \brief Controls member pointer representation format under the MS ABI.
enum PragmaVtorDispKind {
PVDK_Push, ///< #pragma vtordisp(push, mode)
PVDK_Set, ///< #pragma vtordisp(mode)
PVDK_Pop, ///< #pragma vtordisp(pop)
PVDK_Reset ///< #pragma vtordisp()
enum PragmaMsStackAction {
PSK_Reset, // #pragma ()
PSK_Set, // #pragma ("name")
PSK_Push, // #pragma (push[, id])
PSK_Push_Set, // #pragma (push[, id], "name")
PSK_Pop, // #pragma (pop[, id])
PSK_Pop_Set, // #pragma (pop[, id], "name")
/// \brief Whether to insert vtordisps prior to virtual bases in the Microsoft
/// C++ ABI. Possible values are 0, 1, and 2, which mean:
/// 0: Suppress all vtordisps
/// 1: Insert vtordisps in the presence of vbase overrides and non-trivial
/// structors
/// 2: Always insert vtordisps to support RTTI on partially constructed
/// objects
/// The stack always has at least one element in it.
SmallVector<MSVtorDispAttr::Mode, 2> VtorDispModeStack;
/// \brief Source location for newly created implicit MSInheritanceAttrs
SourceLocation ImplicitMSInheritanceAttrLoc;
template<typename ValueType>
struct PragmaStack {
struct Slot {
llvm::StringRef StackSlotLabel;
ValueType Value;
SourceLocation PragmaLocation;
Slot(llvm::StringRef StackSlotLabel,
ValueType Value,
SourceLocation PragmaLocation)
: StackSlotLabel(StackSlotLabel), Value(Value),
PragmaLocation(PragmaLocation) {}
void Act(SourceLocation PragmaLocation,
PragmaMsStackAction Action,
llvm::StringRef StackSlotLabel,
ValueType Value);
explicit PragmaStack(const ValueType &Value)
: CurrentValue(Value) {}
SmallVector<Slot, 2> Stack;
ValueType CurrentValue;
SourceLocation CurrentPragmaLocation;
// FIXME: We should serialize / deserialize these if they occur in a PCH (but
// we shouldn't do so if they're in a module).
PragmaStack<StringLiteral *> DataSegStack;
PragmaStack<StringLiteral *> BSSSegStack;
PragmaStack<StringLiteral *> ConstSegStack;
PragmaStack<StringLiteral *> CodeSegStack;
/// Last section used with #pragma init_seg.
StringLiteral *CurInitSeg;
SourceLocation CurInitSegLoc;
/// VisContext - Manages the stack for \#pragma GCC visibility.
void *VisContext; // Really a "PragmaVisStack*"
/// \brief This represents the last location of a "#pragma clang optimize off"
/// directive if such a directive has not been closed by an "on" yet. If
/// optimizations are currently "on", this is set to an invalid location.
SourceLocation OptimizeOffPragmaLocation;
/// \brief Flag indicating if Sema is building a recovery call expression.
/// This flag is used to avoid building recovery call expressions
/// if Sema is already doing so, which would cause infinite recursions.
bool IsBuildingRecoveryCallExpr;
/// ExprNeedsCleanups - True if the current evaluation context
/// requires cleanups to be run at its conclusion.
bool ExprNeedsCleanups;
/// ExprCleanupObjects - This is the stack of objects requiring
/// cleanup that are created by the current full expression. The
/// element type here is ExprWithCleanups::Object.
SmallVector<BlockDecl*, 8> ExprCleanupObjects;
/// \brief Store a list of either DeclRefExprs or MemberExprs
/// that contain a reference to a variable (constant) that may or may not
/// be odr-used in this Expr, and we won't know until all lvalue-to-rvalue
/// and discarded value conversions have been applied to all subexpressions
/// of the enclosing full expression. This is cleared at the end of each
/// full expression.
llvm::SmallPtrSet<Expr*, 2> MaybeODRUseExprs;
/// \brief Stack containing information about each of the nested
/// function, block, and method scopes that are currently active.
/// This array is never empty. Clients should ignore the first
/// element, which is used to cache a single FunctionScopeInfo
/// that's used to parse every top-level function.
SmallVector<sema::FunctionScopeInfo *, 4> FunctionScopes;
typedef LazyVector<TypedefNameDecl *, ExternalSemaSource,
&ExternalSemaSource::ReadExtVectorDecls, 2, 2>
/// ExtVectorDecls - This is a list all the extended vector types. This allows
/// us to associate a raw vector type with one of the ext_vector type names.
/// This is only necessary for issuing pretty diagnostics.
ExtVectorDeclsType ExtVectorDecls;
/// FieldCollector - Collects CXXFieldDecls during parsing of C++ classes.
std::unique_ptr<CXXFieldCollector> FieldCollector;
typedef llvm::SmallSetVector<const NamedDecl*, 16> NamedDeclSetType;
/// \brief Set containing all declared private fields that are not used.
NamedDeclSetType UnusedPrivateFields;
typedef llvm::SmallPtrSet<const CXXRecordDecl*, 8> RecordDeclSetTy;
/// PureVirtualClassDiagSet - a set of class declarations which we have
/// emitted a list of pure virtual functions. Used to prevent emitting the
/// same list more than once.
std::unique_ptr<RecordDeclSetTy> PureVirtualClassDiagSet;
/// ParsingInitForAutoVars - a set of declarations with auto types for which
/// we are currently parsing the initializer.
llvm::SmallPtrSet<const Decl*, 4> ParsingInitForAutoVars;
/// \brief A mapping from external names to the most recent
/// locally-scoped extern "C" declaration with that name.
/// This map contains external declarations introduced in local
/// scopes, e.g.,
/// \code
/// extern "C" void f() {
/// void foo(int, int);
/// }
/// \endcode
/// Here, the name "foo" will be associated with the declaration of
/// "foo" within f. This name is not visible outside of
/// "f". However, we still find it in two cases:
/// - If we are declaring another global or extern "C" entity with
/// the name "foo", we can find "foo" as a previous declaration,
/// so that the types of this external declaration can be checked
/// for compatibility.
/// - If we would implicitly declare "foo" (e.g., due to a call to
/// "foo" in C when no prototype or definition is visible), then
/// we find this declaration of "foo" and complain that it is
/// not visible.
llvm::DenseMap<DeclarationName, NamedDecl *> LocallyScopedExternCDecls;
/// \brief Look for a locally scoped extern "C" declaration by the given name.
NamedDecl *findLocallyScopedExternCDecl(DeclarationName Name);
typedef LazyVector<VarDecl *, ExternalSemaSource,
&ExternalSemaSource::ReadTentativeDefinitions, 2, 2>
/// \brief All the tentative definitions encountered in the TU.
TentativeDefinitionsType TentativeDefinitions;
typedef LazyVector<const DeclaratorDecl *, ExternalSemaSource,
&ExternalSemaSource::ReadUnusedFileScopedDecls, 2, 2>
/// \brief The set of file scoped decls seen so far that have not been used
/// and must warn if not used. Only contains the first declaration.
UnusedFileScopedDeclsType UnusedFileScopedDecls;
typedef LazyVector<CXXConstructorDecl *, ExternalSemaSource,
&ExternalSemaSource::ReadDelegatingConstructors, 2, 2>
/// \brief All the delegating constructors seen so far in the file, used for
/// cycle detection at the end of the TU.
DelegatingCtorDeclsType DelegatingCtorDecls;
/// \brief All the overriding destructors seen during a class definition
/// (there could be multiple due to nested classes) that had their exception
/// spec checks delayed, plus the overridden destructor.
SmallVector<std::pair<const CXXDestructorDecl*,
const CXXDestructorDecl*>, 2>
/// \brief All the members seen during a class definition which were both
/// explicitly defaulted and had explicitly-specified exception
/// specifications, along with the function type containing their
/// user-specified exception specification. Those exception specifications
/// were overridden with the default specifications, but we still need to
/// check whether they are compatible with the default specification, and
/// we can't do that until the nesting set of class definitions is complete.
SmallVector<std::pair<CXXMethodDecl*, const FunctionProtoType*>, 2>
typedef llvm::DenseMap<const FunctionDecl *, LateParsedTemplate *>
LateParsedTemplateMapT LateParsedTemplateMap;
/// \brief Callback to the parser to parse templated functions when needed.
typedef void LateTemplateParserCB(void *P, LateParsedTemplate &LPT);
LateTemplateParserCB *LateTemplateParser;
void *OpaqueParser;
void SetLateTemplateParser(LateTemplateParserCB *LTP, void *P) {
LateTemplateParser = LTP;
OpaqueParser = P;
class DelayedDiagnostics;
class DelayedDiagnosticsState {
sema::DelayedDiagnosticPool *SavedPool;
friend class Sema::DelayedDiagnostics;
typedef DelayedDiagnosticsState ParsingDeclState;
typedef DelayedDiagnosticsState ProcessingContextState;
/// A class which encapsulates the logic for delaying diagnostics
/// during parsing and other processing.
class DelayedDiagnostics {
/// \brief The current pool of diagnostics into which delayed
/// diagnostics should go.
sema::DelayedDiagnosticPool *CurPool;
DelayedDiagnostics() : CurPool(nullptr) {}
/// Adds a delayed diagnostic.
void add(const sema::DelayedDiagnostic &diag); // in DelayedDiagnostic.h
/// Determines whether diagnostics should be delayed.
bool shouldDelayDiagnostics() { return CurPool != nullptr; }
/// Returns the current delayed-diagnostics pool.
sema::DelayedDiagnosticPool *getCurrentPool() const {
return CurPool;
/// Enter a new scope. Access and deprecation diagnostics will be
/// collected in this pool.
DelayedDiagnosticsState push(sema::DelayedDiagnosticPool &pool) {
DelayedDiagnosticsState state;
state.SavedPool = CurPool;
CurPool = &pool;
return state;
/// Leave a delayed-diagnostic state that was previously pushed.
/// Do not emit any of the diagnostics. This is performed as part
/// of the bookkeeping of popping a pool "properly".
void popWithoutEmitting(DelayedDiagnosticsState state) {
CurPool = state.SavedPool;
/// Enter a new scope where access and deprecation diagnostics are
/// not delayed.
DelayedDiagnosticsState pushUndelayed() {
DelayedDiagnosticsState state;
state.SavedPool = CurPool;
CurPool = nullptr;
return state;
/// Undo a previous pushUndelayed().
void popUndelayed(DelayedDiagnosticsState state) {
assert(CurPool == nullptr);
CurPool = state.SavedPool;
} DelayedDiagnostics;
/// A RAII object to temporarily push a declaration context.
class ContextRAII {
Sema &S;
DeclContext *SavedContext;
ProcessingContextState SavedContextState;
QualType SavedCXXThisTypeOverride;
ContextRAII(Sema &S, DeclContext *ContextToPush, bool NewThisContext = true)
: S(S), SavedContext(S.CurContext),
assert(ContextToPush && "pushing null context");
S.CurContext = ContextToPush;
if (NewThisContext)
S.CXXThisTypeOverride = QualType();
void pop() {
if (!SavedContext) return;
S.CurContext = SavedContext;
S.CXXThisTypeOverride = SavedCXXThisTypeOverride;
SavedContext = nullptr;
~ContextRAII() {
/// \brief RAII object to handle the state changes required to synthesize
/// a function body.
class SynthesizedFunctionScope {
Sema &S;
Sema::ContextRAII SavedContext;
SynthesizedFunctionScope(Sema &S, DeclContext *DC)
: S(S), SavedContext(S, DC)
~SynthesizedFunctionScope() {
/// WeakUndeclaredIdentifiers - Identifiers contained in
/// \#pragma weak before declared. rare. may alias another
/// identifier, declared or undeclared
llvm::DenseMap<IdentifierInfo*,WeakInfo> WeakUndeclaredIdentifiers;
/// ExtnameUndeclaredIdentifiers - Identifiers contained in
/// \#pragma redefine_extname before declared. Used in Solaris system headers
/// to define functions that occur in multiple standards to call the version
/// in the currently selected standard.
llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*> ExtnameUndeclaredIdentifiers;
/// \brief Load weak undeclared identifiers from the external source.
void LoadExternalWeakUndeclaredIdentifiers();
/// WeakTopLevelDecl - Translation-unit scoped declarations generated by
/// \#pragma weak during processing of other Decls.
/// I couldn't figure out a clean way to generate these in-line, so
/// we store them here and handle separately -- which is a hack.
/// It would be best to refactor this.
SmallVector<Decl*,2> WeakTopLevelDecl;
IdentifierResolver IdResolver;
/// Translation Unit Scope - useful to Objective-C actions that need
/// to lookup file scope declarations in the "ordinary" C decl namespace.
/// For example, user-defined classes, built-in "id" type, etc.
Scope *TUScope;
/// \brief The C++ "std" namespace, where the standard library resides.
LazyDeclPtr StdNamespace;
/// \brief The C++ "std::bad_alloc" class, which is defined by the C++
/// standard library.
LazyDeclPtr StdBadAlloc;
/// \brief The C++ "std::initializer_list" template, which is defined in
/// \<initializer_list>.
ClassTemplateDecl *StdInitializerList;
/// \brief The C++ "type_info" declaration, which is defined in \<typeinfo>.
RecordDecl *CXXTypeInfoDecl;
/// \brief The MSVC "_GUID" struct, which is defined in MSVC header files.
RecordDecl *MSVCGuidDecl;
/// \brief Caches identifiers/selectors for NSFoundation APIs.
std::unique_ptr<NSAPI> NSAPIObj;
/// \brief The declaration of the Objective-C NSNumber class.
ObjCInterfaceDecl *NSNumberDecl;
/// \brief Pointer to NSNumber type (NSNumber *).
QualType NSNumberPointer;
/// \brief The Objective-C NSNumber methods used to create NSNumber literals.
ObjCMethodDecl *NSNumberLiteralMethods[NSAPI::NumNSNumberLiteralMethods];
/// \brief The declaration of the Objective-C NSString class.
ObjCInterfaceDecl *NSStringDecl;
/// \brief Pointer to NSString type (NSString *).
QualType NSStringPointer;
/// \brief The declaration of the stringWithUTF8String: method.
ObjCMethodDecl *StringWithUTF8StringMethod;
/// \brief The declaration of the Objective-C NSArray class.
ObjCInterfaceDecl *NSArrayDecl;
/// \brief The declaration of the arrayWithObjects:count: method.
ObjCMethodDecl *ArrayWithObjectsMethod;
/// \brief The declaration of the Objective-C NSDictionary class.
ObjCInterfaceDecl *NSDictionaryDecl;
/// \brief The declaration of the dictionaryWithObjects:forKeys:count: method.
ObjCMethodDecl *DictionaryWithObjectsMethod;
/// \brief id<NSCopying> type.
QualType QIDNSCopying;
/// \brief will hold 'respondsToSelector:'
Selector RespondsToSelectorSel;
/// A flag to remember whether the implicit forms of operator new and delete
/// have been declared.
bool GlobalNewDeleteDeclared;
/// A flag to indicate that we're in a context that permits abstract
/// references to fields. This is really a
bool AllowAbstractFieldReference;
/// \brief Describes how the expressions currently being parsed are
/// evaluated at run-time, if at all.
enum ExpressionEvaluationContext {
/// \brief The current expression and its subexpressions occur within an
/// unevaluated operand (C++11 [expr]p7), such as the subexpression of
/// \c sizeof, where the type of the expression may be significant but
/// no code will be generated to evaluate the value of the expression at
/// run time.
/// \brief The current expression occurs within an unevaluated
/// operand that unconditionally permits abstract references to
/// fields, such as a SIZE operator in MS-style inline assembly.
/// \brief The current context is "potentially evaluated" in C++11 terms,
/// but the expression is evaluated at compile-time (like the values of
/// cases in a switch statement).
/// \brief The current expression is potentially evaluated at run time,
/// which means that code may be generated to evaluate the value of the
/// expression at run time.
/// \brief The current expression is potentially evaluated, but any
/// declarations referenced inside that expression are only used if
/// in fact the current expression is used.
/// This value is used when parsing default function arguments, for which
/// we would like to provide diagnostics (e.g., passing non-POD arguments
/// through varargs) but do not want to mark declarations as "referenced"
/// until the default argument is used.
/// \brief Data structure used to record current or nested
/// expression evaluation contexts.
struct ExpressionEvaluationContextRecord {
/// \brief The expression evaluation context.
ExpressionEvaluationContext Context;
/// \brief Whether the enclosing context needed a cleanup.
bool ParentNeedsCleanups;
/// \brief Whether we are in a decltype expression.
bool IsDecltype;
/// \brief The number of active cleanup objects when we entered
/// this expression evaluation context.
unsigned NumCleanupObjects;
llvm::SmallPtrSet<Expr*, 2> SavedMaybeODRUseExprs;
/// \brief The lambdas that are present within this context, if it
/// is indeed an unevaluated context.
SmallVector<LambdaExpr *, 2> Lambdas;
/// \brief The declaration that provides context for lambda expressions
/// and block literals if the normal declaration context does not
/// suffice, e.g., in a default function argument.
Decl *ManglingContextDecl;
/// \brief The context information used to mangle lambda expressions
/// and block literals within this context.
/// This mangling information is allocated lazily, since most contexts
/// do not have lambda expressions or block literals.
IntrusiveRefCntPtr<MangleNumberingContext> MangleNumbering;
/// \brief If we are processing a decltype type, a set of call expressions
/// for which we have deferred checking the completeness of the return type.
SmallVector<CallExpr *, 8> DelayedDecltypeCalls;
/// \brief If we are processing a decltype type, a set of temporary binding
/// expressions for which we have deferred checking the destructor.
SmallVector<CXXBindTemporaryExpr *, 8> DelayedDecltypeBinds;
ExpressionEvaluationContextRecord(ExpressionEvaluationContext Context,
unsigned NumCleanupObjects,
bool ParentNeedsCleanups,
Decl *ManglingContextDecl,
bool IsDecltype)
: Context(Context), ParentNeedsCleanups(ParentNeedsCleanups),
IsDecltype(IsDecltype), NumCleanupObjects(NumCleanupObjects),
ManglingContextDecl(ManglingContextDecl), MangleNumbering() { }
/// \brief Retrieve the mangling numbering context, used to consistently
/// number constructs like lambdas for mangling.
MangleNumberingContext &getMangleNumberingContext(ASTContext &Ctx);
bool isUnevaluated() const {
return Context == Unevaluated || Context == UnevaluatedAbstract;
/// A stack of expression evaluation contexts.
SmallVector<ExpressionEvaluationContextRecord, 8> ExprEvalContexts;
/// \brief Compute the mangling number context for a lambda expression or
/// block literal.
/// \param DC - The DeclContext containing the lambda expression or
/// block literal.
/// \param[out] ManglingContextDecl - Returns the ManglingContextDecl
/// associated with the context, if relevant.
MangleNumberingContext *getCurrentMangleNumberContext(
const DeclContext *DC,
Decl *&ManglingContextDecl);
/// SpecialMemberOverloadResult - The overloading result for a special member
/// function.
/// This is basically a wrapper around PointerIntPair. The lowest bits of the
/// integer are used to determine whether overload resolution succeeded.
class SpecialMemberOverloadResult : public llvm::FastFoldingSetNode {
enum Kind {
llvm::PointerIntPair<CXXMethodDecl*, 2> Pair;
SpecialMemberOverloadResult(const llvm::FoldingSetNodeID &ID)
: FastFoldingSetNode(ID)
CXXMethodDecl *getMethod() const { return Pair.getPointer(); }
void setMethod(CXXMethodDecl *MD) { Pair.setPointer(MD); }
Kind getKind() const { return static_cast<Kind>(Pair.getInt()); }
void setKind(Kind K) { Pair.setInt(K); }
/// \brief A cache of special member function overload resolution results
/// for C++ records.
llvm::FoldingSet<SpecialMemberOverloadResult> SpecialMemberCache;
/// \brief The kind of translation unit we are processing.
/// When we're processing a complete translation unit, Sema will perform
/// end-of-translation-unit semantic tasks (such as creating
/// initializers for tentative definitions in C) once parsing has
/// completed. Modules and precompiled headers perform different kinds of
/// checks.
TranslationUnitKind TUKind;
llvm::BumpPtrAllocator BumpAlloc;
/// \brief The number of SFINAE diagnostics that have been trapped.
unsigned NumSFINAEErrors;
typedef llvm::DenseMap<ParmVarDecl *, llvm::TinyPtrVector<ParmVarDecl *>>
/// \brief A mapping from parameters with unparsed default arguments to the
/// set of instantiations of each parameter.
/// This mapping is a temporary data structure used when parsing
/// nested class templates or nested classes of class templates,
/// where we might end up instantiating an inner class before the
/// default arguments of its methods have been parsed.
UnparsedDefaultArgInstantiationsMap UnparsedDefaultArgInstantiations;
// Contains the locations of the beginning of unparsed default
// argument locations.
llvm::DenseMap<ParmVarDecl *, SourceLocation> UnparsedDefaultArgLocs;
/// UndefinedInternals - all the used, undefined objects which require a
/// definition in this translation unit.
llvm::DenseMap<NamedDecl *, SourceLocation> UndefinedButUsed;
/// Obtain a sorted list of functions that are undefined but ODR-used.
void getUndefinedButUsed(
SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> > &Undefined);
typedef std::pair<ObjCMethodList, ObjCMethodList> GlobalMethods;
typedef llvm::DenseMap<Selector, GlobalMethods> GlobalMethodPool;
/// Method Pool - allows efficient lookup when typechecking messages to "id".
/// We need to maintain a list, since selectors can have differing signatures
/// across classes. In Cocoa, this happens to be extremely uncommon (only 1%
/// of selectors are "overloaded").
/// At the head of the list it is recorded whether there were 0, 1, or >= 2
/// methods inside categories with a particular selector.
GlobalMethodPool MethodPool;
/// Method selectors used in a \@selector expression. Used for implementation
/// of -Wselector.
llvm::DenseMap<Selector, SourceLocation> ReferencedSelectors;
/// Kinds of C++ special members.
enum CXXSpecialMember {
typedef std::pair<CXXRecordDecl*, CXXSpecialMember> SpecialMemberDecl;
/// The C++ special members which we are currently in the process of
/// declaring. If this process recursively triggers the declaration of the
/// same special member, we should act as if it is not yet declared.
llvm::SmallSet<SpecialMemberDecl, 4> SpecialMembersBeingDeclared;
void ReadMethodPool(Selector Sel);
/// Private Helper predicate to check for 'self'.
bool isSelfExpr(Expr *RExpr);
bool isSelfExpr(Expr *RExpr, const ObjCMethodDecl *Method);
/// \brief Cause the active diagnostic on the DiagosticsEngine to be
/// emitted. This is closely coupled to the SemaDiagnosticBuilder class and
/// should not be used elsewhere.
void EmitCurrentDiagnostic(unsigned DiagID);
/// Records and restores the FP_CONTRACT state on entry/exit of compound
/// statements.
class FPContractStateRAII {
FPContractStateRAII(Sema& S)
: S(S), OldFPContractState(S.FPFeatures.fp_contract) {}
~FPContractStateRAII() {
S.FPFeatures.fp_contract = OldFPContractState;
Sema& S;
bool OldFPContractState : 1;
void addImplicitTypedef(StringRef Name, QualType T);
Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
TranslationUnitKind TUKind = TU_Complete,
CodeCompleteConsumer *CompletionConsumer = nullptr);
/// \brief Perform initialization that occurs after the parser has been
/// initialized but before it parses anything.
void Initialize();
const LangOptions &getLangOpts() const { return LangOpts; }
OpenCLOptions &getOpenCLOptions() { return OpenCLFeatures; }
FPOptions &getFPOptions() { return FPFeatures; }
DiagnosticsEngine &getDiagnostics() const { return Diags; }
SourceManager &getSourceManager() const { return SourceMgr; }
Preprocessor &getPreprocessor() const { return PP; }
ASTContext &getASTContext() const { return Context; }
ASTConsumer &getASTConsumer() const { return Consumer; }
ASTMutationListener *getASTMutationListener() const;
ExternalSemaSource* getExternalSource() const { return ExternalSource; }
///\brief Registers an external source. If an external source already exists,
/// creates a multiplex external source and appends to it.
///\param[in] E - A non-null external sema source.
void addExternalSource(ExternalSemaSource *E);
void PrintStats() const;
/// \brief Helper class that creates diagnostics with optional
/// template instantiation stacks.
/// This class provides a wrapper around the basic DiagnosticBuilder
/// class that emits diagnostics. SemaDiagnosticBuilder is
/// responsible for emitting the diagnostic (as DiagnosticBuilder
/// does) and, if the diagnostic comes from inside a template
/// instantiation, printing the template instantiation stack as
/// well.
class SemaDiagnosticBuilder : public DiagnosticBuilder {
Sema &SemaRef;
unsigned DiagID;
SemaDiagnosticBuilder(DiagnosticBuilder &DB, Sema &SemaRef, unsigned DiagID)
: DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) { }
~SemaDiagnosticBuilder() {
// If we aren't active, there is nothing to do.
if (!isActive()) return;
// Otherwise, we need to emit the diagnostic. First flush the underlying
// DiagnosticBuilder data, and clear the diagnostic builder itself so it
// won't emit the diagnostic in its own destructor.
// This seems wasteful, in that as written the DiagnosticBuilder dtor will
// do its own needless checks to see if the diagnostic needs to be
// emitted. However, because we take care to ensure that the builder
// objects never escape, a sufficiently smart compiler will be able to
// eliminate that code.
// Dispatch to Sema to emit the diagnostic.
/// Teach operator<< to produce an object of the correct type.
template<typename T>
friend const SemaDiagnosticBuilder &operator<<(
const SemaDiagnosticBuilder &Diag, const T &Value) {
const DiagnosticBuilder &BaseDiag = Diag;
BaseDiag << Value;
return Diag;
/// \brief Emit a diagnostic.
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) {
DiagnosticBuilder DB = Diags.Report(Loc, DiagID);
return SemaDiagnosticBuilder(DB, *this, DiagID);
/// \brief Emit a partial diagnostic.
SemaDiagnosticBuilder Diag(SourceLocation Loc, const PartialDiagnostic& PD);
/// \brief Build a partial diagnostic.
PartialDiagnostic PDiag(unsigned DiagID = 0); // in SemaInternal.h
bool findMacroSpelling(SourceLocation &loc, StringRef name);
/// \brief Get a string to suggest for zero-initialization of a type.
getFixItZeroInitializerForType(QualType T, SourceLocation Loc) const;
std::string getFixItZeroLiteralForType(QualType T, SourceLocation Loc) const;
/// \brief Calls \c Lexer::getLocForEndOfToken()
SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset = 0);
/// \brief Retrieve the module loader associated with the preprocessor.
ModuleLoader &getModuleLoader() const;
void ActOnEndOfTranslationUnit();
void CheckDelegatingCtorCycles();
Scope *getScopeForContext(DeclContext *Ctx);
void PushFunctionScope();
void PushBlockScope(Scope *BlockScope, BlockDecl *Block);
sema::LambdaScopeInfo *PushLambdaScope();
/// \brief This is used to inform Sema what the current TemplateParameterDepth
/// is during Parsing. Currently it is used to pass on the depth
/// when parsing generic lambda 'auto' parameters.
void RecordParsingTemplateParameterDepth(unsigned Depth);
void PushCapturedRegionScope(Scope *RegionScope, CapturedDecl *CD,
RecordDecl *RD,
CapturedRegionKind K);
PopFunctionScopeInfo(const sema::AnalysisBasedWarnings::Policy *WP = nullptr,
const Decl *D = nullptr,
const BlockExpr *blkExpr = nullptr);
sema::FunctionScopeInfo *getCurFunction() const {
return FunctionScopes.back();
sema::FunctionScopeInfo *getEnclosingFunction() const {
if (FunctionScopes.empty())
return nullptr;
for (int e = FunctionScopes.size()-1; e >= 0; --e) {
if (isa<sema::BlockScopeInfo>(FunctionScopes[e]))
return FunctionScopes[e];
return nullptr;
template <typename ExprT>
void recordUseOfEvaluatedWeak(const ExprT *E, bool IsRead=true) {
if (!isUnevaluatedContext())
getCurFunction()->recordUseOfWeak(E, IsRead);
void PushCompoundScope();
void PopCompoundScope();
sema::CompoundScopeInfo &getCurCompoundScope() const;
bool hasAnyUnrecoverableErrorsInThisFunction() const;
/// \brief Retrieve the current block, if any.
sema::BlockScopeInfo *getCurBlock();
/// \brief Retrieve the current lambda scope info, if any.
sema::LambdaScopeInfo *getCurLambda();
/// \brief Retrieve the current generic lambda info, if any.
sema::LambdaScopeInfo *getCurGenericLambda();
/// \brief Retrieve the current captured region, if any.
sema::CapturedRegionScopeInfo *getCurCapturedRegion();
/// WeakTopLevelDeclDecls - access to \#pragma weak-generated Decls
SmallVectorImpl<Decl *> &WeakTopLevelDecls() { return WeakTopLevelDecl; }
void ActOnComment(SourceRange Comment);
// Type Analysis / Processing: SemaType.cpp.
QualType BuildQualifiedType(QualType T, SourceLocation Loc, Qualifiers Qs,
const DeclSpec *DS = nullptr);
QualType BuildQualifiedType(QualType T, SourceLocation Loc, unsigned CVRA,
const DeclSpec *DS = nullptr);
QualType BuildPointerType(QualType T,
SourceLocation Loc, DeclarationName Entity);
QualType BuildReferenceType(QualType T, bool LValueRef,
SourceLocation Loc, DeclarationName Entity);
QualType BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
Expr *ArraySize, unsigned Quals,
SourceRange Brackets, DeclarationName Entity);
QualType BuildExtVectorType(QualType T, Expr *ArraySize,
SourceLocation AttrLoc);
bool CheckFunctionReturnType(QualType T, SourceLocation Loc);
/// \brief Build a function type.
/// This routine checks the function type according to C++ rules and
/// under the assumption that the result type and parameter types have
/// just been instantiated from a template. It therefore duplicates
/// some of the behavior of GetTypeForDeclarator, but in a much
/// simpler form that is only suitable for this narrow use case.
/// \param T The return type of the function.
/// \param ParamTypes The parameter types of the function. This array
/// will be modified to account for adjustments to the types of the
/// function parameters.
/// \param Loc The location of the entity whose type involves this
/// function type or, if there is no such entity, the location of the
/// type that will have function type.
/// \param Entity The name of the entity that involves the function
/// type, if known.
/// \param EPI Extra information about the function type. Usually this will
/// be taken from an existing function with the same prototype.
/// \returns A suitable function type, if there are no errors. The
/// unqualified type will always be a FunctionProtoType.
/// Otherwise, returns a NULL type.
QualType BuildFunctionType(QualType T,
MutableArrayRef<QualType> ParamTypes,
SourceLocation Loc, DeclarationName Entity,
const FunctionProtoType::ExtProtoInfo &EPI);
QualType BuildMemberPointerType(QualType T, QualType Class,
SourceLocation Loc,
DeclarationName Entity);
QualType BuildBlockPointerType(QualType T,
SourceLocation Loc, DeclarationName Entity);
QualType BuildParenType(QualType T);
QualType BuildAtomicType(QualType T, SourceLocation Loc);
TypeSourceInfo *GetTypeForDeclarator(Declarator &D, Scope *S);
TypeSourceInfo *GetTypeForDeclaratorCast(Declarator &D, QualType FromTy);
TypeSourceInfo *GetTypeSourceInfoForDeclarator(Declarator &D, QualType T,
TypeSourceInfo *ReturnTypeInfo);
/// \brief Package the given type and TSI into a ParsedType.
ParsedType CreateParsedType(QualType T, TypeSourceInfo *TInfo);
DeclarationNameInfo GetNameForDeclarator(Declarator &D);
DeclarationNameInfo GetNameFromUnqualifiedId(const UnqualifiedId &Name);
static QualType GetTypeFromParser(ParsedType Ty,
TypeSourceInfo **TInfo = nullptr);
CanThrowResult canThrow(const Expr *E);
const FunctionProtoType *ResolveExceptionSpec(SourceLocation Loc,
const FunctionProtoType *FPT);
void UpdateExceptionSpec(FunctionDecl *FD,
const FunctionProtoType::ExtProtoInfo &EPI);
bool CheckSpecifiedExceptionType(QualType &T, const SourceRange &Range);
bool CheckDistantExceptionSpec(QualType T);
bool CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New);
bool CheckEquivalentExceptionSpec(
const FunctionProtoType *Old, SourceLocation OldLoc,
const FunctionProtoType *New, SourceLocation NewLoc);
bool CheckEquivalentExceptionSpec(
const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
const FunctionProtoType *Old, SourceLocation OldLoc,
const FunctionProtoType *New, SourceLocation NewLoc,
bool *MissingExceptionSpecification = nullptr,
bool *MissingEmptyExceptionSpecification = nullptr,
bool AllowNoexceptAllMatchWithNoSpec = false,
bool IsOperatorNew = false);
bool CheckExceptionSpecSubset(
const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
const FunctionProtoType *Superset, SourceLocation SuperLoc,
const FunctionProtoType *Subset, SourceLocation SubLoc);
bool CheckParamExceptionSpec(const PartialDiagnostic & NoteID,
const FunctionProtoType *Target, SourceLocation TargetLoc,
const FunctionProtoType *Source, SourceLocation SourceLoc);
TypeResult ActOnTypeName(Scope *S, Declarator &D);
/// \brief The parser has parsed the context-sensitive type 'instancetype'
/// in an Objective-C message declaration. Return the appropriate type.
ParsedType ActOnObjCInstanceType(SourceLocation Loc);
/// \brief Abstract class used to diagnose incomplete types.
struct TypeDiagnoser {
bool Suppressed;
TypeDiagnoser(bool Suppressed = false) : Suppressed(Suppressed) { }
virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) = 0;
virtual ~TypeDiagnoser() {}
static int getPrintable(int I) { return I; }
static unsigned getPrintable(unsigned I) { return I; }
static bool getPrintable(bool B) { return B; }
static const char * getPrintable(const char *S) { return S; }
static StringRef getPrintable(StringRef S) { return S; }
static const std::string &getPrintable(const std::string &S) { return S; }
static const IdentifierInfo *getPrintable(const IdentifierInfo *II) {
return II;
static DeclarationName getPrintable(DeclarationName N) { return N; }
static QualType getPrintable(QualType T) { return T; }
static SourceRange getPrintable(SourceRange R) { return R; }
static SourceRange getPrintable(SourceLocation L) { return L; }
static SourceRange getPrintable(Expr *E) { return E->getSourceRange(); }
static SourceRange getPrintable(TypeLoc TL) { return TL.getSourceRange();}
template<typename T1>
class BoundTypeDiagnoser1 : public TypeDiagnoser {
unsigned DiagID;
const T1 &Arg1;
BoundTypeDiagnoser1(unsigned DiagID, const T1 &Arg1)
: TypeDiagnoser(DiagID == 0), DiagID(DiagID), Arg1(Arg1) { }
void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
if (Suppressed) return;
S.Diag(Loc, DiagID) << getPrintable(Arg1) << T;
virtual ~BoundTypeDiagnoser1() { }
template<typename T1, typename T2>
class BoundTypeDiagnoser2 : public TypeDiagnoser {
unsigned DiagID;
const T1 &Arg1;
const T2 &Arg2;
BoundTypeDiagnoser2(unsigned DiagID, const T1 &Arg1,
const T2 &Arg2)
: TypeDiagnoser(DiagID == 0), DiagID(DiagID), Arg1(Arg1),
Arg2(Arg2) { }
void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
if (Suppressed) return;
S.Diag(Loc, DiagID) << getPrintable(Arg1) << getPrintable(Arg2) << T;
virtual ~BoundTypeDiagnoser2() { }
template<typename T1, typename T2, typename T3>
class BoundTypeDiagnoser3 : public TypeDiagnoser {
unsigned DiagID;
const T1 &Arg1;
const T2 &Arg2;
const T3 &Arg3;
BoundTypeDiagnoser3(unsigned DiagID, const T1 &Arg1,
const T2 &Arg2, const T3 &Arg3)
: TypeDiagnoser(DiagID == 0), DiagID(DiagID), Arg1(Arg1),
Arg2(Arg2), Arg3(Arg3) { }
void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
if (Suppressed) return;
S.Diag(Loc, DiagID)
<< getPrintable(Arg1) << getPrintable(Arg2) << getPrintable(Arg3) << T;
virtual ~BoundTypeDiagnoser3() { }
bool RequireCompleteTypeImpl(SourceLocation Loc, QualType T,
TypeDiagnoser &Diagnoser);
bool RequireCompleteType(SourceLocation Loc, QualType T,
TypeDiagnoser &Diagnoser);
bool RequireCompleteType(SourceLocation Loc, QualType T,
unsigned DiagID);
template<typename T1>
bool RequireCompleteType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1) {
BoundTypeDiagnoser1<T1> Diagnoser(DiagID, Arg1);
return RequireCompleteType(Loc, T, Diagnoser);
template<typename T1, typename T2>
bool RequireCompleteType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1, const T2 &Arg2) {
BoundTypeDiagnoser2<T1, T2> Diagnoser(DiagID, Arg1, Arg2);
return RequireCompleteType(Loc, T, Diagnoser);
template<typename T1, typename T2, typename T3>
bool RequireCompleteType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1, const T2 &Arg2,
const T3 &Arg3) {
BoundTypeDiagnoser3<T1, T2, T3> Diagnoser(DiagID, Arg1, Arg2,
return RequireCompleteType(Loc, T, Diagnoser);
bool RequireCompleteExprType(Expr *E, TypeDiagnoser &Diagnoser);
bool RequireCompleteExprType(Expr *E, unsigned DiagID);
template<typename T1>
bool RequireCompleteExprType(Expr *E, unsigned DiagID, const T1 &Arg1) {
BoundTypeDiagnoser1<T1> Diagnoser(DiagID, Arg1);
return RequireCompleteExprType(E, Diagnoser);
template<typename T1, typename T2>
bool RequireCompleteExprType(Expr *E, unsigned DiagID, const T1 &Arg1,
const T2 &Arg2) {
BoundTypeDiagnoser2<T1, T2> Diagnoser(DiagID, Arg1, Arg2);
return RequireCompleteExprType(E, Diagnoser);
template<typename T1, typename T2, typename T3>
bool RequireCompleteExprType(Expr *E, unsigned DiagID, const T1 &Arg1,
const T2 &Arg2, const T3 &Arg3) {
BoundTypeDiagnoser3<T1, T2, T3> Diagnoser(DiagID, Arg1, Arg2,
return RequireCompleteExprType(E, Diagnoser);
bool RequireLiteralType(SourceLocation Loc, QualType T,
TypeDiagnoser &Diagnoser);
bool RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID);
template<typename T1>
bool RequireLiteralType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1) {
BoundTypeDiagnoser1<T1> Diagnoser(DiagID, Arg1);
return RequireLiteralType(Loc, T, Diagnoser);
template<typename T1, typename T2>
bool RequireLiteralType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1, const T2 &Arg2) {
BoundTypeDiagnoser2<T1, T2> Diagnoser(DiagID, Arg1, Arg2);
return RequireLiteralType(Loc, T, Diagnoser);
template<typename T1, typename T2, typename T3>
bool RequireLiteralType(SourceLocation Loc, QualType T,
unsigned DiagID, const T1 &Arg1, const T2 &Arg2,
const T3 &Arg3) {
BoundTypeDiagnoser3<T1, T2, T3> Diagnoser(DiagID, Arg1, Arg2,
return RequireLiteralType(Loc, T, Diagnoser);
QualType getElaboratedType(ElaboratedTypeKeyword Keyword,
const CXXScopeSpec &SS, QualType T);
QualType BuildTypeofExprType(Expr *E, SourceLocation Loc);
QualType BuildDecltypeType(Expr *E, SourceLocation Loc);
QualType BuildUnaryTransformType(QualType BaseType,
UnaryTransformType::UTTKind UKind,
SourceLocation Loc);
// Symbol table / Decl tracking callbacks: SemaDecl.cpp.
/// List of decls defined in a function prototype. This contains EnumConstants
/// that incorrectly end up in translation unit scope because there is no
/// function to pin them on. ActOnFunctionDeclarator reads this list and patches
/// them into the FunctionDecl.
std::vector<NamedDecl*> DeclsInPrototypeScope;
DeclGroupPtrTy ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType = nullptr);
void DiagnoseUseOfUnimplementedSelectors();
bool isSimpleTypeSpecifier(tok::TokenKind Kind) const;
ParsedType getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
Scope *S, CXXScopeSpec *SS = nullptr,
bool isClassName = false,
bool HasTrailingDot = false,
ParsedType ObjectType = ParsedType(),
bool IsCtorOrDtorName = false,
bool WantNontrivialTypeSourceInfo = false,
IdentifierInfo **CorrectedII = nullptr);
TypeSpecifierType isTagName(IdentifierInfo &II, Scope *S);
bool isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S);
void DiagnoseUnknownTypeName(IdentifierInfo *&II,
SourceLocation IILoc,
Scope *S,
CXXScopeSpec *SS,
ParsedType &SuggestedType,
bool AllowClassTemplates = false);
/// \brief For compatibility with MSVC, we delay parsing of some default
/// template type arguments until instantiation time. Emits a warning and
/// returns a synthesized DependentNameType that isn't really dependent on any
/// other template arguments.
ParsedType ActOnDelayedDefaultTemplateArg(const IdentifierInfo &II,
SourceLocation NameLoc);
/// \brief Describes the result of the name lookup and resolution performed
/// by \c ClassifyName().
enum NameClassificationKind {
class NameClassification {
NameClassificationKind Kind;
ExprResult Expr;
TemplateName Template;
ParsedType Type;
const IdentifierInfo *Keyword;
explicit NameClassification(NameClassificationKind Kind) : Kind(Kind) {}
NameClassification(ExprResult Expr) : Kind(NC_Expression), Expr(Expr) {}
NameClassification(ParsedType Type) : Kind(NC_Type), Type(Type) {}
NameClassification(const IdentifierInfo *Keyword)
: Kind(NC_Keyword), Keyword(Keyword) { }
static NameClassification Error() {
return NameClassification(NC_Error);
static NameClassification Unknown() {
return NameClassification(NC_Unknown);
static NameClassification NestedNameSpecifier() {
return NameClassification(NC_NestedNameSpecifier);
static NameClassification TypeTemplate(TemplateName Name) {
NameClassification Result(NC_TypeTemplate);
Result.Template = Name;
return Result;
static NameClassification VarTemplate(TemplateName Name) {
NameClassification Result(NC_VarTemplate);
Result.Template = Name;
return Result;
static NameClassification FunctionTemplate(TemplateName Name) {
NameClassification Result(NC_FunctionTemplate);
Result.Template = Name;
return Result;
NameClassificationKind getKind() const { return Kind; }
ParsedType getType() const {
assert(Kind == NC_Type);
return Type;
ExprResult getExpression() const {
assert(Kind == NC_Expression);
return Expr;
TemplateName getTemplateName() const {
assert(Kind == NC_TypeTemplate || Kind == NC_FunctionTemplate ||
Kind == NC_VarTemplate);
return Template;
TemplateNameKind getTemplateNameKind() const {
switch (Kind) {
case NC_TypeTemplate:
return TNK_Type_template;
case NC_FunctionTemplate:
return TNK_Function_template;
case NC_VarTemplate:
return TNK_Var_template;
llvm_unreachable("unsupported name classification.");
/// \brief Perform name lookup on the given name, classifying it based on
/// the results of name lookup and the following token.
/// This routine is used by the parser to resolve identifiers and help direct
/// parsing. When the identifier cannot be found, this routine will attempt
/// to correct the typo and classify based on the resulting name.
/// \param S The scope in which we're performing name lookup.
/// \param SS The nested-name-specifier that precedes the name.
/// \param Name The identifier. If typo correction finds an alternative name,
/// this pointer parameter will be updated accordingly.
/// \param NameLoc The location of the identifier.
/// \param NextToken The token following the identifier. Used to help
/// disambiguate the name.
/// \param IsAddressOfOperand True if this name is the operand of a unary
/// address of ('&') expression, assuming it is classified as an
/// expression.
/// \param CCC The correction callback, if typo correction is desired.
NameClassification ClassifyName(Scope *S,
CXXScopeSpec &SS,
IdentifierInfo *&Name,
SourceLocation NameLoc,
const Token &NextToken,
bool IsAddressOfOperand,
CorrectionCandidateCallback *CCC = nullptr);
Decl *ActOnDeclarator(Scope *S, Declarator &D);
NamedDecl *HandleDeclarator(Scope *S, Declarator &D,
MultiTemplateParamsArg TemplateParameterLists);
void RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S);
bool DiagnoseClassNameShadow(DeclContext *DC, DeclarationNameInfo Info);
bool diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
DeclarationName Name,
SourceLocation Loc);
diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
SourceLocation FallbackLoc,
SourceLocation ConstQualLoc = SourceLocation(),
SourceLocation VolatileQualLoc = SourceLocation(),
SourceLocation RestrictQualLoc = SourceLocation(),
SourceLocation AtomicQualLoc = SourceLocation());
static bool adjustContextForLocalExternDecl(DeclContext *&DC);
void DiagnoseFunctionSpecifiers(const DeclSpec &DS);
void CheckShadow(Scope *S, VarDecl *D, const LookupResult& R);
void CheckShadow(Scope *S, VarDecl *D);
void CheckCastAlign(Expr *Op, QualType T, SourceRange TRange);
void CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *D);
NamedDecl* ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
TypeSourceInfo *TInfo,
LookupResult &Previous);
NamedDecl* ActOnTypedefNameDecl(Scope* S, DeclContext* DC, TypedefNameDecl *D,
LookupResult &Previous, bool &Redeclaration);
NamedDecl *ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
TypeSourceInfo *TInfo,
LookupResult &Previous,
MultiTemplateParamsArg TemplateParamLists,
bool &AddToScope);
// Returns true if the variable declaration is a redeclaration
bool CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous);
void CheckVariableDeclarationType(VarDecl *NewVD);
void CheckCompleteVariableDeclaration(VarDecl *var);
void MaybeSuggestAddingStaticToDecl(const FunctionDecl *D);
NamedDecl* ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
TypeSourceInfo *TInfo,
LookupResult &Previous,
MultiTemplateParamsArg TemplateParamLists,
bool &AddToScope);
bool AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD);
bool CheckConstexprFunctionDecl(const FunctionDecl *FD);
bool CheckConstexprFunctionBody(const FunctionDecl *FD, Stmt *Body);
void DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD);
void FindHiddenVirtualMethods(CXXMethodDecl *MD,
SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
void NoteHiddenVirtualMethods(CXXMethodDecl *MD,
SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
// Returns true if the function declaration is a redeclaration
bool CheckFunctionDeclaration(Scope *S,
FunctionDecl *NewFD, LookupResult &Previous,
bool IsExplicitSpecialization);
void CheckMain(FunctionDecl *FD, const DeclSpec &D);
void CheckMSVCRTEntryPoint(FunctionDecl *FD);
Decl *ActOnParamDeclarator(Scope *S, Declarator &D);
ParmVarDecl *BuildParmVarDeclForTypedef(DeclContext *DC,
SourceLocation Loc,
QualType T);
ParmVarDecl *CheckParameter(DeclContext *DC, SourceLocation StartLoc,
SourceLocation NameLoc, IdentifierInfo *Name,
QualType T, TypeSourceInfo *TSInfo,
StorageClass SC);
void ActOnParamDefaultArgument(Decl *param,
SourceLocation EqualLoc,
Expr *defarg);
void ActOnParamUnparsedDefaultArgument(Decl *param,
SourceLocation EqualLoc,
SourceLocation ArgLoc);
void ActOnParamDefaultArgumentError(Decl *param, SourceLocation EqualLoc);
bool SetParamDefaultArgument(ParmVarDecl *Param, Expr *DefaultArg,
SourceLocation EqualLoc);
void AddInitializerToDecl(Decl *dcl, Expr *init, bool DirectInit,
bool TypeMayContainAuto);
void ActOnUninitializedDecl(Decl *dcl, bool TypeMayContainAuto);
void ActOnInitializerError(Decl *Dcl);
void ActOnCXXForRangeDecl(Decl *D);
StmtResult ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
IdentifierInfo *Ident,
ParsedAttributes &Attrs,
SourceLocation AttrEnd);
void SetDeclDeleted(Decl *dcl, SourceLocation DelLoc);
void SetDeclDefaulted(Decl *dcl, SourceLocation DefaultLoc);
void FinalizeDeclaration(Decl *D);
DeclGroupPtrTy FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
ArrayRef<Decl *> Group);
DeclGroupPtrTy BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
bool TypeMayContainAuto = true);
/// Should be called on all declarations that might have attached
/// documentation comments.
void ActOnDocumentableDecl(Decl *D);
void ActOnDocumentableDecls(ArrayRef<Decl *> Group);
void ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
SourceLocation LocAfterDecls);
void CheckForFunctionRedefinition(FunctionDecl *FD,
const FunctionDecl *EffectiveDefinition =
Decl *ActOnStartOfFunctionDef(Scope *S, Declarator &D);
Decl *ActOnStartOfFunctionDef(Scope *S, Decl *D);
void ActOnStartOfObjCMethodDef(Scope *S, Decl *D);
bool isObjCMethodDecl(Decl *D) {
return D && isa<ObjCMethodDecl>(D);
/// \brief Determine whether we can delay parsing the body of a function or
/// function template until it is used, assuming we don't care about emitting
/// code for that function.
/// This will be \c false if we may need the body of the function in the
/// middle of parsing an expression (where it's impractical to switch to
/// parsing a different function), for instance, if it's constexpr in C++11
/// or has an 'auto' return type in C++14. These cases are essentially bugs.
bool canDelayFunctionBody(const Declarator &D);
/// \brief Determine whether we can skip parsing the body of a function
/// definition, assuming we don't care about analyzing its body or emitting
/// code for that function.
/// This will be \c false only if we may need the body of the function in
/// order to parse the rest of the program (for instance, if it is
/// \c constexpr in C++11 or has an 'auto' return type in C++14).
bool canSkipFunctionBody(Decl *D);
void computeNRVO(Stmt *Body, sema::FunctionScopeInfo *Scope);
Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body);
Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body, bool IsInstantiation);
Decl *ActOnSkippedFunctionBody(Decl *Decl);
void ActOnFinishInlineMethodDef(CXXMethodDecl *D);
/// ActOnFinishDelayedAttribute - Invoked when we have finished parsing an
/// attribute for which parsing is delayed.
void ActOnFinishDelayedAttribute(Scope *S, Decl *D, ParsedAttributes &Attrs);
/// \brief Diagnose any unused parameters in the given sequence of
/// ParmVarDecl pointers.
void DiagnoseUnusedParameters(ParmVarDecl * const *Begin,
ParmVarDecl * const *End);
/// \brief Diagnose whether the size of parameters or return value of a
/// function or obj-c method definition is pass-by-value and larger than a
/// specified threshold.
void DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Begin,
ParmVarDecl * const *End,
QualType ReturnTy,
NamedDecl *D);
void DiagnoseInvalidJumps(Stmt *Body);
Decl *ActOnFileScopeAsmDecl(Expr *expr,
SourceLocation AsmLoc,
SourceLocation RParenLoc);
/// \brief Handle a C++11 empty-declaration and attribute-declaration.
Decl *ActOnEmptyDeclaration(Scope *S,
AttributeList *AttrList,
SourceLocation SemiLoc);
/// \brief The parser has processed a module import declaration.
/// \param AtLoc The location of the '@' symbol, if any.
/// \param ImportLoc The location of the 'import' keyword.
/// \param Path The module access path.
DeclResult ActOnModuleImport(SourceLocation AtLoc, SourceLocation ImportLoc,
ModuleIdPath Path);
/// \brief The parser has processed a module import translated from a
/// #include or similar preprocessing directive.
void ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod);
/// \brief Create an implicit import of the given module at the given
/// source location, for error recovery, if possible.
/// This routine is typically used when an entity found by name lookup
/// is actually hidden within a module that we know about but the user
/// has forgotten to import.
void createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
Module *Mod);
/// \brief Retrieve a suitable printing policy.
PrintingPolicy getPrintingPolicy() const {
return getPrintingPolicy(Context, PP);
/// \brief Retrieve a suitable printing policy.
static PrintingPolicy getPrintingPolicy(const ASTContext &Ctx,
const Preprocessor &PP);
/// Scope actions.
void ActOnPopScope(SourceLocation Loc, Scope *S);
void ActOnTranslationUnitScope(Scope *S);
Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
DeclSpec &DS);
Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
DeclSpec &DS,
MultiTemplateParamsArg TemplateParams,
bool IsExplicitInstantiation = false);
Decl *BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
AccessSpecifier AS,
RecordDecl *Record,
const PrintingPolicy &Policy);
Decl *BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
RecordDecl *Record);
bool isAcceptableTagRedeclaration(const TagDecl *Previous,
TagTypeKind NewTag, bool isDefinition,
SourceLocation NewTagLoc,
const IdentifierInfo &Name);
enum TagUseKind {
TUK_Reference, // Reference to a tag: 'struct foo *X;'
TUK_Declaration, // Fwd decl of a tag: 'struct foo;'
TUK_Definition, // Definition of a tag: 'struct foo { int X; } Y;'
TUK_Friend // Friend declaration: 'friend struct foo;'
Decl *ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
SourceLocation KWLoc, CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
AttributeList *Attr, AccessSpecifier AS,
SourceLocation ModulePrivateLoc,
MultiTemplateParamsArg TemplateParameterLists,
bool &OwnedDecl, bool &IsDependent,
SourceLocation ScopedEnumKWLoc,
bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
bool IsTypeSpecifier);
Decl *ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
unsigned TagSpec, SourceLocation TagLoc,
CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
AttributeList *Attr,
MultiTemplateParamsArg TempParamLists);
TypeResult ActOnDependentTag(Scope *S,
unsigned TagSpec,
TagUseKind TUK,
const CXXScopeSpec &SS,
IdentifierInfo *Name,
SourceLocation TagLoc,
SourceLocation NameLoc);
void ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
IdentifierInfo *ClassName,
SmallVectorImpl<Decl *> &Decls);
Decl *ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth);
FieldDecl *HandleField(Scope *S, RecordDecl *TagD, SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth,
InClassInitStyle InitStyle,
AccessSpecifier AS);
MSPropertyDecl *HandleMSProperty(Scope *S, RecordDecl *TagD,
SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth,
InClassInitStyle InitStyle,
AccessSpecifier AS,
AttributeList *MSPropertyAttr);
FieldDecl *CheckFieldDecl(DeclarationName Name, QualType T,
TypeSourceInfo *TInfo,
RecordDecl *Record, SourceLocation Loc,
bool Mutable, Expr *BitfieldWidth,
InClassInitStyle InitStyle,
SourceLocation TSSL,
AccessSpecifier AS, NamedDecl *PrevDecl,
Declarator *D = nullptr);
bool CheckNontrivialField(FieldDecl *FD);
void DiagnoseNontrivial(const CXXRecordDecl *Record, CXXSpecialMember CSM);
bool SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
bool Diagnose = false);
CXXSpecialMember getSpecialMember(const CXXMethodDecl *MD);
void ActOnLastBitfield(SourceLocation DeclStart,
SmallVectorImpl<Decl *> &AllIvarDecls);
Decl *ActOnIvar(Scope *S, SourceLocation DeclStart,
Declarator &D, Expr *BitfieldWidth,
tok::ObjCKeywordKind visibility);
// This is used for both record definitions and ObjC interface declarations.
void ActOnFields(Scope* S, SourceLocation RecLoc, Decl *TagDecl,
ArrayRef<Decl *> Fields,
SourceLocation LBrac, SourceLocation RBrac,
AttributeList *AttrList);
/// ActOnTagStartDefinition - Invoked when we have entered the
/// scope of a tag's definition (e.g., for an enumeration, class,
/// struct, or union).
void ActOnTagStartDefinition(Scope *S, Decl *TagDecl);
Decl *ActOnObjCContainerStartDefinition(Decl *IDecl);
/// ActOnStartCXXMemberDeclarations - Invoked when we have parsed a
/// C++ record definition's base-specifiers clause and are starting its
/// member declarations.
void ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagDecl,
SourceLocation FinalLoc,
bool IsFinalSpelledSealed,
SourceLocation LBraceLoc);
/// ActOnTagFinishDefinition - Invoked once we have finished parsing
/// the definition of a tag (enumeration, class, struct, or union).
void ActOnTagFinishDefinition(Scope *S, Decl *TagDecl,
SourceLocation RBraceLoc);
void ActOnObjCContainerFinishDefinition();
/// \brief Invoked when we must temporarily exit the objective-c container
/// scope for parsing/looking-up C constructs.
/// Must be followed by a call to \see ActOnObjCReenterContainerContext
void ActOnObjCTemporaryExitContainerContext(DeclContext *DC);
void ActOnObjCReenterContainerContext(DeclContext *DC);
/// ActOnTagDefinitionError - Invoked when there was an unrecoverable
/// error parsing the definition of a tag.
void ActOnTagDefinitionError(Scope *S, Decl *TagDecl);
EnumConstantDecl *CheckEnumConstant(EnumDecl *Enum,
EnumConstantDecl *LastEnumConst,
SourceLocation IdLoc,
IdentifierInfo *Id,
Expr *val);
bool CheckEnumUnderlyingType(TypeSourceInfo *TI);
bool CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped,
QualType EnumUnderlyingTy, const EnumDecl *Prev);
Decl *ActOnEnumConstant(Scope *S, Decl *EnumDecl, Decl *LastEnumConstant,
SourceLocation IdLoc, IdentifierInfo *Id,
AttributeList *Attrs,
SourceLocation EqualLoc, Expr *Val);
void ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
SourceLocation RBraceLoc, Decl *EnumDecl,
ArrayRef<Decl *> Elements,
Scope *S, AttributeList *Attr);
DeclContext *getContainingDC(DeclContext *DC);
/// Set the current declaration context until it gets popped.
void PushDeclContext(Scope *S, DeclContext *DC);
void PopDeclContext();
/// EnterDeclaratorContext - Used when we must lookup names in the context
/// of a declarator's nested name specifier.
void EnterDeclaratorContext(Scope *S, DeclContext *DC);
void ExitDeclaratorContext(Scope *S);
/// Push the parameters of D, which must be a function, into scope.
void ActOnReenterFunctionContext(Scope* S, Decl* D);
void ActOnExitFunctionContext();
DeclContext *getFunctionLevelDeclContext();
/// getCurFunctionDecl - If inside of a function body, this returns a pointer
/// to the function decl for the function being parsed. If we're currently
/// in a 'block', this returns the containing context.
FunctionDecl *getCurFunctionDecl();
/// getCurMethodDecl - If inside of a method body, this returns a pointer to
/// the method decl for the method being parsed. If we're currently
/// in a 'block', this returns the containing context.
ObjCMethodDecl *getCurMethodDecl();
/// getCurFunctionOrMethodDecl - Return the Decl for the current ObjC method
/// or C function we're in, otherwise return null. If we're currently
/// in a 'block', this returns the containing context.
NamedDecl *getCurFunctionOrMethodDecl();
/// Add this decl to the scope shadowed decl chains.
void PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext = true);
/// \brief Make the given externally-produced declaration visible at the
/// top level scope.
/// \param D The externally-produced declaration to push.
/// \param Name The name of the externally-produced declaration.
void pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name);
/// isDeclInScope - If 'Ctx' is a function/method, isDeclInScope returns true
/// if 'D' is in Scope 'S', otherwise 'S' is ignored and isDeclInScope returns
/// true if 'D' belongs to the given declaration context.
/// \param AllowInlineNamespace If \c true, allow the declaration to be in the
/// enclosing namespace set of the context, rather than contained
/// directly within it.
bool isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S = nullptr,
bool AllowInlineNamespace = false);
/// Finds the scope corresponding to the given decl context, if it
/// happens to be an enclosing scope. Otherwise return NULL.
static Scope *getScopeForDeclContext(Scope *S, DeclContext *DC);
/// Subroutines of ActOnDeclarator().
TypedefDecl *ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
TypeSourceInfo *TInfo);
bool isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New);
/// Attribute merging methods. Return true if a new attribute was added.
AvailabilityAttr *mergeAvailabilityAttr(NamedDecl *D, SourceRange Range,
IdentifierInfo *Platform,
VersionTuple Introduced,
VersionTuple Deprecated,
VersionTuple Obsoleted,
bool IsUnavailable,
StringRef Message,
bool Override,
unsigned AttrSpellingListIndex);
TypeVisibilityAttr *mergeTypeVisibilityAttr(Decl *D, SourceRange Range,
TypeVisibilityAttr::VisibilityType Vis,
unsigned AttrSpellingListIndex);
VisibilityAttr *mergeVisibilityAttr(Decl *D, SourceRange Range,
VisibilityAttr::VisibilityType Vis,
unsigned AttrSpellingListIndex);
DLLImportAttr *mergeDLLImportAttr(Decl *D, SourceRange Range,
unsigned AttrSpellingListIndex);
DLLExportAttr *mergeDLLExportAttr(Decl *D, SourceRange Range,
unsigned AttrSpellingListIndex);
MSInheritanceAttr *
mergeMSInheritanceAttr(Decl *D, SourceRange Range, bool BestCase,
unsigned AttrSpellingListIndex,
MSInheritanceAttr::Spelling SemanticSpelling);
FormatAttr *mergeFormatAttr(Decl *D, SourceRange Range,
IdentifierInfo *Format, int FormatIdx,
int FirstArg, unsigned AttrSpellingListIndex);
SectionAttr *mergeSectionAttr(Decl *D, SourceRange Range, StringRef Name,
unsigned AttrSpellingListIndex);
/// \brief Describes the kind of merge to perform for availability
/// attributes (including "deprecated", "unavailable", and "availability").
enum AvailabilityMergeKind {
/// \brief Don't merge availability attributes at all.
/// \brief Merge availability attributes for a redeclaration, which requires
/// an exact match.
/// \brief Merge availability attributes for an override, which requires
/// an exact match or a weakening of constraints.
void mergeDeclAttributes(NamedDecl *New, Decl *Old,
AvailabilityMergeKind AMK = AMK_Redeclaration);
void MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls);
bool MergeFunctionDecl(FunctionDecl *New, NamedDecl *&Old, Scope *S,
bool MergeTypeWithOld);
bool MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
Scope *S, bool MergeTypeWithOld);
void mergeObjCMethodDecls(ObjCMethodDecl *New, ObjCMethodDecl *Old);
void MergeVarDecl(VarDecl *New, LookupResult &Previous);
void MergeVarDeclTypes(VarDecl *New, VarDecl *Old, bool MergeTypeWithOld);
void MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old);
bool MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old, Scope *S);
// AssignmentAction - This is used by all the assignment diagnostic functions
// to represent what is actually causing the operation
enum AssignmentAction {
/// C++ Overloading.
enum OverloadKind {
/// This is a legitimate overload: the existing declarations are
/// functions or function templates with different signatures.
/// This is not an overload because the signature exactly matches
/// an existing declaration.
/// This is not an overload because the lookup results contain a
/// non-function.
OverloadKind CheckOverload(Scope *S,
FunctionDecl *New,
const LookupResult &OldDecls,
NamedDecl *&OldDecl,
bool IsForUsingDecl);
bool IsOverload(FunctionDecl *New, FunctionDecl *Old, bool IsForUsingDecl);
/// \brief Checks availability of the function depending on the current
/// function context.Inside an unavailable function,unavailability is ignored.
/// \returns true if \p FD is unavailable and current context is inside
/// an available function, false otherwise.
bool isFunctionConsideredUnavailable(FunctionDecl *FD);
TryImplicitConversion(Expr *From, QualType ToType,
bool SuppressUserConversions,
bool AllowExplicit,
bool InOverloadResolution,
bool CStyle,
bool AllowObjCWritebackConversion);
bool IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType);
bool IsFloatingPointPromotion(QualType FromType, QualType ToType);
bool IsComplexPromotion(QualType FromType, QualType ToType);
bool IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
bool InOverloadResolution,
QualType& ConvertedType, bool &IncompatibleObjC);
bool isObjCPointerConversion(QualType FromType, QualType ToType,
QualType& ConvertedType, bool &IncompatibleObjC);
bool isObjCWritebackConversion(QualType FromType, QualType ToType,
QualType &ConvertedType);
bool IsBlockPointerConversion(QualType FromType, QualType ToType,
QualType& ConvertedType);
bool FunctionParamTypesAreEqual(const FunctionProtoType *OldType,
const FunctionProtoType *NewType,
unsigned *ArgPos = nullptr);
void HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
QualType FromType, QualType ToType);
CastKind PrepareCastToObjCObjectPointer(ExprResult &E);
bool CheckPointerConversion(Expr *From, QualType ToType,
CastKind &Kind,
CXXCastPath& BasePath,
bool IgnoreBaseAccess);
bool IsMemberPointerConversion(Expr *From, QualType FromType, QualType ToType,
bool InOverloadResolution,
QualType &ConvertedType);
bool CheckMemberPointerConversion(Expr *From, QualType ToType,
CastKind &Kind,
CXXCastPath &BasePath,
bool IgnoreBaseAccess);
bool IsQualificationConversion(QualType FromType, QualType ToType,
bool CStyle, bool &ObjCLifetimeConversion);
bool IsNoReturnConversion(QualType FromType, QualType ToType,
QualType &ResultTy);
bool DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType);
bool isSameOrCompatibleFunctionType(CanQualType Param, CanQualType Arg);
ExprResult PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
const VarDecl *NRVOCandidate,
QualType ResultType,
Expr *Value,
bool AllowNRVO = true);
bool CanPerformCopyInitialization(const InitializedEntity &Entity,
ExprResult Init);
ExprResult PerformCopyInitialization(const InitializedEntity &Entity,
SourceLocation EqualLoc,
ExprResult Init,
bool TopLevelOfInitList = false,
bool AllowExplicit = false);
ExprResult PerformObjectArgumentInitialization(Expr *From,
NestedNameSpecifier *Qualifier,
NamedDecl *FoundDecl,
CXXMethodDecl *Method);
ExprResult PerformContextuallyConvertToBool(Expr *From);
ExprResult PerformContextuallyConvertToObjCPointer(Expr *From);
/// Contexts in which a converted constant expression is required.
enum CCEKind {
CCEK_CaseValue, ///< Expression in a case label.
CCEK_Enumerator, ///< Enumerator value with fixed underlying type.
CCEK_TemplateArg, ///< Value of a non-type template parameter.
CCEK_NewExpr ///< Constant expression in a noptr-new-declarator.
ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
llvm::APSInt &Value, CCEKind CCE);
/// \brief Abstract base class used to perform a contextual implicit
/// conversion from an expression to any type passing a filter.
class ContextualImplicitConverter {
bool Suppress;
bool SuppressConversion;
ContextualImplicitConverter(bool Suppress = false,
bool SuppressConversion = false)
: Suppress(Suppress), SuppressConversion(SuppressConversion) {}
/// \brief Determine whether the specified type is a valid destination type
/// for this conversion.
virtual bool match(QualType T) = 0;
/// \brief Emits a diagnostic complaining that the expression does not have
/// integral or enumeration type.
virtual SemaDiagnosticBuilder
diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) = 0;
/// \brief Emits a diagnostic when the expression has incomplete class type.
virtual SemaDiagnosticBuilder
diagnoseIncomplete(Sema &S, SourceLocation Loc, QualType T) = 0;
/// \brief Emits a diagnostic when the only matching conversion function
/// is explicit.
virtual SemaDiagnosticBuilder diagnoseExplicitConv(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
/// \brief Emits a note for the explicit conversion function.
virtual SemaDiagnosticBuilder
noteExplicitConv(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
/// \brief Emits a diagnostic when there are multiple possible conversion
/// functions.
virtual SemaDiagnosticBuilder
diagnoseAmbiguous(Sema &S, SourceLocation Loc, QualType T) = 0;
/// \brief Emits a note for one of the candidate conversions.
virtual SemaDiagnosticBuilder
noteAmbiguous(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
/// \brief Emits a diagnostic when we picked a conversion function
/// (for cases when we are not allowed to pick a conversion function).
virtual SemaDiagnosticBuilder diagnoseConversion(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
virtual ~ContextualImplicitConverter() {}
class ICEConvertDiagnoser : public ContextualImplicitConverter {
bool AllowScopedEnumerations;
ICEConvertDiagnoser(bool AllowScopedEnumerations,
bool Suppress, bool SuppressConversion)
: ContextualImplicitConverter(Suppress, SuppressConversion),
AllowScopedEnumerations(AllowScopedEnumerations) {}
/// Match an integral or (possibly scoped) enumeration type.
bool match(QualType T) override;
diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) override {
return diagnoseNotInt(S, Loc, T);
/// \brief Emits a diagnostic complaining that the expression does not have
/// integral or enumeration type.
virtual SemaDiagnosticBuilder
diagnoseNotInt(Sema &S, SourceLocation Loc, QualType T) = 0;
/// Perform a contextual implicit conversion.
ExprResult PerformContextualImplicitConversion(
SourceLocation Loc, Expr *FromE, ContextualImplicitConverter &Converter);
enum ObjCSubscriptKind {
ObjCSubscriptKind CheckSubscriptingKind(Expr *FromE);
// Note that LK_String is intentionally after the other literals, as
// this is used for diagnostics logic.
enum ObjCLiteralKind {
ObjCLiteralKind CheckLiteralKind(Expr *FromE);
ExprResult PerformObjectMemberConversion(Expr *From,
NestedNameSpecifier *Qualifier,
NamedDecl *FoundDecl,
NamedDecl *Member);
// Members have to be NamespaceDecl* or TranslationUnitDecl*.
// TODO: make this is a typesafe union.
typedef llvm::SmallPtrSet<DeclContext *, 16> AssociatedNamespaceSet;
typedef llvm::SmallPtrSet<CXXRecordDecl *, 16> AssociatedClassSet;
void AddOverloadCandidate(FunctionDecl *Function,
DeclAccessPair FoundDecl,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool SuppressUserConversions = false,
bool PartialOverloading = false,
bool AllowExplicit = false);
void AddFunctionCandidates(const UnresolvedSetImpl &Functions,
ArrayRef<Expr *> Args,
OverloadCandidateSet &CandidateSet,
bool SuppressUserConversions = false,
TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr);
void AddMethodCandidate(DeclAccessPair FoundDecl,
QualType ObjectType,
Expr::Classification ObjectClassification,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool SuppressUserConversion = false);
void AddMethodCandidate(CXXMethodDecl *Method,
DeclAccessPair FoundDecl,
CXXRecordDecl *ActingContext, QualType ObjectType,
Expr::Classification ObjectClassification,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool SuppressUserConversions = false);
void AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl,
DeclAccessPair FoundDecl,
CXXRecordDecl *ActingContext,
TemplateArgumentListInfo *ExplicitTemplateArgs,
QualType ObjectType,
Expr::Classification ObjectClassification,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool SuppressUserConversions = false);
void AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate,
DeclAccessPair FoundDecl,
TemplateArgumentListInfo *ExplicitTemplateArgs,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool SuppressUserConversions = false);
void AddConversionCandidate(CXXConversionDecl *Conversion,
DeclAccessPair FoundDecl,
CXXRecordDecl *ActingContext,
Expr *From, QualType ToType,
OverloadCandidateSet& CandidateSet,
bool AllowObjCConversionOnExplicit);
void AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate,
DeclAccessPair FoundDecl,
CXXRecordDecl *ActingContext,
Expr *From, QualType ToType,
OverloadCandidateSet &CandidateSet,
bool AllowObjCConversionOnExplicit);
void AddSurrogateCandidate(CXXConversionDecl *Conversion,
DeclAccessPair FoundDecl,
CXXRecordDecl *ActingContext,
const FunctionProtoType *Proto,
Expr *Object, ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet);
void AddMemberOperatorCandidates(OverloadedOperatorKind Op,
SourceLocation OpLoc, ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
SourceRange OpRange = SourceRange());
void AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys,
ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet,
bool IsAssignmentOperator = false,
unsigned NumContextualBoolArguments = 0);
void AddBuiltinOperatorCandidates(OverloadedOperatorKind Op,
SourceLocation OpLoc, ArrayRef<Expr *> Args,
OverloadCandidateSet& CandidateSet);
void AddArgumentDependentLookupCandidates(DeclarationName Name,
SourceLocation Loc,
ArrayRef<Expr *> Args,
TemplateArgumentListInfo *ExplicitTemplateArgs,
OverloadCandidateSet& CandidateSet,
bool PartialOverloading = false);
// Emit as a 'note' the specific overload candidate
void NoteOverloadCandidate(FunctionDecl *Fn, QualType DestType = QualType());
// Emit as a series of 'note's all template and non-templates
// identified by the expression Expr
void NoteAllOverloadCandidates(Expr* E, QualType DestType = QualType());
/// Check the enable_if expressions on the given function. Returns the first
/// failing attribute, or NULL if they were all successful.
EnableIfAttr *CheckEnableIf(FunctionDecl *Function, ArrayRef<Expr *> Args,
bool MissingImplicitThis = false);
// [PossiblyAFunctionType] --> [Return]
// NonFunctionType --> NonFunctionType
// R (A) --> R(A)
// R (*)(A) --> R (A)
// R (&)(A) --> R (A)
// R (S::*)(A) --> R (A)
QualType ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType);
FunctionDecl *
ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr,
QualType TargetType,
bool Complain,
DeclAccessPair &Found,
bool *pHadMultipleCandidates = nullptr);
FunctionDecl *
ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl,
bool Complain = false,
DeclAccessPair *Found = nullptr);
bool ResolveAndFixSingleFunctionTemplateSpecialization(
ExprResult &SrcExpr,
bool DoFunctionPointerConverion = false,
bool Complain = false,
const SourceRange& OpRangeForComplaining = SourceRange(),
QualType DestTypeForComplaining = QualType(),
unsigned DiagIDForComplaining = 0);
Expr *FixOverloadedFunctionReference(Expr *E,
DeclAccessPair FoundDecl,
FunctionDecl *Fn);
ExprResult FixOverloadedFunctionReference(ExprResult,
DeclAccessPair FoundDecl,
FunctionDecl *Fn);
void AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE,
ArrayRef<Expr *> Args,
OverloadCandidateSet &CandidateSet,
bool PartialOverloading = false);
// An enum used to represent the different possible results of building a
// range-based for loop.
enum ForRangeStatus {
// An enum to represent whether something is dealing with a call to begin()
// or a call to end() in a range-based for loop.
enum BeginEndFunction {
ForRangeStatus BuildForRangeBeginEndCall(Scope *S, SourceLocation Loc,
SourceLocation RangeLoc,
VarDecl *Decl,
BeginEndFunction BEF,
const DeclarationNameInfo &NameInfo,
LookupResult &MemberLookup,
OverloadCandidateSet *CandidateSet,
Expr *Range, ExprResult *CallExpr);
ExprResult BuildOverloadedCallExpr(Scope *S, Expr *Fn,
UnresolvedLookupExpr *ULE,
SourceLocation LParenLoc,
MultiExprArg Args,
SourceLocation RParenLoc,
Expr *ExecConfig,
bool AllowTypoCorrection=true);
bool buildOverloadedCallSet(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE,
MultiExprArg Args, SourceLocation RParenLoc,
OverloadCandidateSet *CandidateSet,
ExprResult *Result);
ExprResult CreateOverloadedUnaryOp(SourceLocation OpLoc,
unsigned Opc,
const UnresolvedSetImpl &Fns,
Expr *input);
ExprResult CreateOverloadedBinOp(SourceLocation OpLoc,
unsigned Opc,
const UnresolvedSetImpl &Fns,
Expr *LHS, Expr *RHS);
ExprResult CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
SourceLocation RLoc,
Expr *Base,Expr *Idx);
BuildCallToMemberFunction(Scope *S, Expr *MemExpr,
SourceLocation LParenLoc,
MultiExprArg Args,
SourceLocation RParenLoc);
BuildCallToObjectOfClassType(Scope *S, Expr *Object, SourceLocation LParenLoc,
MultiExprArg Args,
SourceLocation RParenLoc);
ExprResult BuildOverloadedArrowExpr(Scope *S, Expr *Base,
SourceLocation OpLoc,
bool *NoArrowOperatorFound = nullptr);
/// CheckCallReturnType - Checks that a call expression's return type is
/// complete. Returns true on failure. The location passed in is the location
/// that best represents the call.
bool CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
CallExpr *CE, FunctionDecl *FD);
/// Helpers for dealing with blocks and functions.
bool CheckParmsForFunctionDef(ParmVarDecl *const *Param,
ParmVarDecl *const *ParamEnd,
bool CheckParameterNames);
void CheckCXXDefaultArguments(FunctionDecl *FD);
void CheckExtraCXXDefaultArguments(Declarator &D);
Scope *getNonFieldDeclScope(Scope *S);
/// \name Name lookup
/// These routines provide name lookup that is used during semantic
/// analysis to resolve the various kinds of names (identifiers,
/// overloaded operator names, constructor names, etc.) into zero or
/// more declarations within a particular scope. The major entry
/// points are LookupName, which performs unqualified name lookup,
/// and LookupQualifiedName, which performs qualified name lookup.
/// All name lookup is performed based on some specific criteria,
/// which specify what names will be visible to name lookup and how
/// far name lookup should work. These criteria are important both
/// for capturing language semantics (certain lookups will ignore
/// certain names, for example) and for performance, since name
/// lookup is often a bottleneck in the compilation of C++. Name
/// lookup criteria is specified via the LookupCriteria enumeration.
/// The results of name lookup can vary based on the kind of name
/// lookup performed, the current language, and the translation
/// unit. In C, for example, name lookup will either return nothing
/// (no entity found) or a single declaration. In C++, name lookup
/// can additionally refer to a set of overloaded functions or
/// result in an ambiguity. All of the possible results of name
/// lookup are captured by the LookupResult class, which provides
/// the ability to distinguish among them.
/// @brief Describes the kind of name lookup to perform.
enum LookupNameKind {
/// Ordinary name lookup, which finds ordinary names (functions,
/// variables, typedefs, etc.) in C and most kinds of names
/// (functions, variables, members, types, etc.) in C++.
LookupOrdinaryName = 0,
/// Tag name lookup, which finds the names of enums, classes,
/// structs, and unions.
/// Label name lookup.
/// Member name lookup, which finds the names of
/// class/struct/union members.
/// Look up of an operator name (e.g., operator+) for use with
/// operator overloading. This lookup is similar to ordinary name
/// lookup, but will ignore any declarations that are class members.
/// Look up of a name that precedes the '::' scope resolution
/// operator in C++. This lookup completely ignores operator, object,
/// function, and enumerator names (C++ [basic.lookup.qual]p1).
/// Look up a namespace name within a C++ using directive or
/// namespace alias definition, ignoring non-namespace names (C++
/// [basic.lookup.udir]p1).
/// Look up all declarations in a scope with the given name,
/// including resolved using declarations. This is appropriate
/// for checking redeclarations for a using declaration.
/// Look up an ordinary name that is going to be redeclared as a
/// name with linkage. This lookup ignores any declarations that
/// are outside of the current scope unless they have linkage. See
/// C99 6.2.2p4-5 and C++ []p6.
/// Look up a friend of a local class. This lookup does not look
/// outside the innermost non-class scope. See C++11 [class.friend]p11.
/// Look up the name of an Objective-C protocol.
/// Look up implicit 'self' parameter of an objective-c method.
/// \brief Look up any declaration with any name.
/// \brief Specifies whether (or how) name lookup is being performed for a
/// redeclaration (vs. a reference).
enum RedeclarationKind {
/// \brief The lookup is a reference to this name that is not for the
/// purpose of redeclaring the name.
NotForRedeclaration = 0,
/// \brief The lookup results will be used for redeclaration of a name,
/// if an entity by that name already exists.
/// \brief The possible outcomes of name lookup for a literal operator.
enum LiteralOperatorLookupResult {
/// \brief The lookup resulted in an error.
/// \brief The lookup found a single 'cooked' literal operator, which
/// expects a normal literal to be built and passed to it.
/// \brief The lookup found a single 'raw' literal operator, which expects
/// a string literal containing the spelling of the literal token.
/// \brief The lookup found an overload set of literal operator templates,
/// which expect the characters of the spelling of the literal token to be
/// passed as a non-type template argument pack.
/// \brief The lookup found an overload set of literal operator templates,
/// which expect the character type and characters of the spelling of the
/// string literal token to be passed as template arguments.
SpecialMemberOverloadResult *LookupSpecialMember(CXXRecordDecl *D,
CXXSpecialMember SM,
bool ConstArg,
bool VolatileArg,
bool RValueThis,
bool ConstThis,
bool VolatileThis);
bool CppLookupName(LookupResult &R, Scope *S</