1	//===- Decl.cpp - Declaration AST Node Implementation ---------------------===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	// This file implements the Decl subclasses.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#include "clang/AST/Decl.h"
14	#include "Linkage.h"
15	#include "clang/AST/ASTContext.h"
16	#include "clang/AST/ASTDiagnostic.h"
17	#include "clang/AST/ASTLambda.h"
18	#include "clang/AST/ASTMutationListener.h"
19	#include "clang/AST/Attr.h"
20	#include "clang/AST/CanonicalType.h"
21	#include "clang/AST/DeclBase.h"
22	#include "clang/AST/DeclCXX.h"
23	#include "clang/AST/DeclObjC.h"
24	#include "clang/AST/DeclOpenMP.h"
25	#include "clang/AST/DeclTemplate.h"
26	#include "clang/AST/DeclarationName.h"
27	#include "clang/AST/Expr.h"
28	#include "clang/AST/ExprCXX.h"
29	#include "clang/AST/ExternalASTSource.h"
30	#include "clang/AST/ODRHash.h"
31	#include "clang/AST/PrettyDeclStackTrace.h"
32	#include "clang/AST/PrettyPrinter.h"
33	#include "clang/AST/Randstruct.h"
34	#include "clang/AST/RecordLayout.h"
35	#include "clang/AST/Redeclarable.h"
36	#include "clang/AST/Stmt.h"
37	#include "clang/AST/TemplateBase.h"
38	#include "clang/AST/Type.h"
39	#include "clang/AST/TypeLoc.h"
40	#include "clang/Basic/Builtins.h"
41	#include "clang/Basic/IdentifierTable.h"
42	#include "clang/Basic/LLVM.h"
43	#include "clang/Basic/LangOptions.h"
44	#include "clang/Basic/Linkage.h"
45	#include "clang/Basic/Module.h"
46	#include "clang/Basic/NoSanitizeList.h"
47	#include "clang/Basic/PartialDiagnostic.h"
48	#include "clang/Basic/Sanitizers.h"
49	#include "clang/Basic/SourceLocation.h"
50	#include "clang/Basic/SourceManager.h"
51	#include "clang/Basic/Specifiers.h"
52	#include "clang/Basic/TargetCXXABI.h"
53	#include "clang/Basic/TargetInfo.h"
54	#include "clang/Basic/Visibility.h"
55	#include "llvm/ADT/APSInt.h"
56	#include "llvm/ADT/ArrayRef.h"
57	#include "llvm/ADT/STLExtras.h"
58	#include "llvm/ADT/SmallVector.h"
59	#include "llvm/ADT/StringRef.h"
60	#include "llvm/ADT/StringSwitch.h"
61	#include "llvm/Support/Casting.h"
62	#include "llvm/Support/ErrorHandling.h"
63	#include "llvm/Support/raw_ostream.h"
64	#include "llvm/TargetParser/Triple.h"
65	#include <algorithm>
66	#include <cassert>
67	#include <cstddef>
68	#include <cstring>
69	#include <memory>
70	#include <optional>
71	#include <string>
72	#include <tuple>
73	#include <type_traits>
74
75	using namespace clang;
76
77	Decl *clang::getPrimaryMergedDecl(Decl *D) {
78	return D->getASTContext().getPrimaryMergedDecl(D);
79	}
80
81	void PrettyDeclStackTraceEntry::print(raw_ostream &OS) const {
82	SourceLocation Loc = this->Loc;
83	if (!Loc.isValid() && TheDecl) Loc = TheDecl->getLocation();
84	if (Loc.isValid()) {
85	Loc.print(OS, SM: Context.getSourceManager());
86	OS << ": ";
87	}
88	OS << Message;
89
90	if (auto *ND = dyn_cast_if_present<NamedDecl>(Val: TheDecl)) {
91	OS << " '";
92	ND->getNameForDiagnostic(OS, Policy: Context.getPrintingPolicy(), Qualified: true);
93	OS << "'";
94	}
95
96	OS << '\n';
97	}
98
99	// Defined here so that it can be inlined into its direct callers.
100	bool Decl::isOutOfLine() const {
101	return !getLexicalDeclContext()->Equals(DC: getDeclContext());
102	}
103
104	TranslationUnitDecl::TranslationUnitDecl(ASTContext &ctx)
105	: Decl(TranslationUnit, nullptr, SourceLocation()),
106	DeclContext(TranslationUnit), redeclarable_base(ctx), Ctx(ctx) {}
107
108	//===----------------------------------------------------------------------===//
109	// NamedDecl Implementation
110	//===----------------------------------------------------------------------===//
111
112	// Visibility rules aren't rigorously externally specified, but here
113	// are the basic principles behind what we implement:
114	//
115	// 1. An explicit visibility attribute is generally a direct expression
116	// of the user's intent and should be honored. Only the innermost
117	// visibility attribute applies. If no visibility attribute applies,
118	// global visibility settings are considered.
119	//
120	// 2. There is one caveat to the above: on or in a template pattern,
121	// an explicit visibility attribute is just a default rule, and
122	// visibility can be decreased by the visibility of template
123	// arguments. But this, too, has an exception: an attribute on an
124	// explicit specialization or instantiation causes all the visibility
125	// restrictions of the template arguments to be ignored.
126	//
127	// 3. A variable that does not otherwise have explicit visibility can
128	// be restricted by the visibility of its type.
129	//
130	// 4. A visibility restriction is explicit if it comes from an
131	// attribute (or something like it), not a global visibility setting.
132	// When emitting a reference to an external symbol, visibility
133	// restrictions are ignored unless they are explicit.
134	//
135	// 5. When computing the visibility of a non-type, including a
136	// non-type member of a class, only non-type visibility restrictions
137	// are considered: the 'visibility' attribute, global value-visibility
138	// settings, and a few special cases like __private_extern.
139	//
140	// 6. When computing the visibility of a type, including a type member
141	// of a class, only type visibility restrictions are considered:
142	// the 'type_visibility' attribute and global type-visibility settings.
143	// However, a 'visibility' attribute counts as a 'type_visibility'
144	// attribute on any declaration that only has the former.
145	//
146	// The visibility of a "secondary" entity, like a template argument,
147	// is computed using the kind of that entity, not the kind of the
148	// primary entity for which we are computing visibility. For example,
149	// the visibility of a specialization of either of these templates:
150	// template <class T, bool (&compare)(T, X)> bool has_match(list<T>, X);
151	// template <class T, bool (&compare)(T, X)> class matcher;
152	// is restricted according to the type visibility of the argument 'T',
153	// the type visibility of 'bool(&)(T,X)', and the value visibility of
154	// the argument function 'compare'. That 'has_match' is a value
155	// and 'matcher' is a type only matters when looking for attributes
156	// and settings from the immediate context.
157
158	/// Does this computation kind permit us to consider additional
159	/// visibility settings from attributes and the like?
160	static bool hasExplicitVisibilityAlready(LVComputationKind computation) {
161	return computation.IgnoreExplicitVisibility;
162	}
163
164	/// Given an LVComputationKind, return one of the same type/value sort
165	/// that records that it already has explicit visibility.
166	static LVComputationKind
167	withExplicitVisibilityAlready(LVComputationKind Kind) {
168	Kind.IgnoreExplicitVisibility = true;
169	return Kind;
170	}
171
172	static std::optional<Visibility> getExplicitVisibility(const NamedDecl *D,
173	LVComputationKind kind) {
174	assert(!kind.IgnoreExplicitVisibility &&
175	"asking for explicit visibility when we shouldn't be");
176	return D->getExplicitVisibility(kind: kind.getExplicitVisibilityKind());
177	}
178
179	/// Is the given declaration a "type" or a "value" for the purposes of
180	/// visibility computation?
181	static bool usesTypeVisibility(const NamedDecl *D) {
182	return isa<TypeDecl>(Val: D) ||
183	isa<ClassTemplateDecl>(Val: D) ||
184	isa<ObjCInterfaceDecl>(Val: D);
185	}
186
187	/// Does the given declaration have member specialization information,
188	/// and if so, is it an explicit specialization?
189	template <class T>
190	static std::enable_if_t<!std::is_base_of_v<RedeclarableTemplateDecl, T>, bool>
191	isExplicitMemberSpecialization(const T *D) {
192	if (const MemberSpecializationInfo *member =
193	D->getMemberSpecializationInfo()) {
194	return member->isExplicitSpecialization();
195	}
196	return false;
197	}
198
199	/// For templates, this question is easier: a member template can't be
200	/// explicitly instantiated, so there's a single bit indicating whether
201	/// or not this is an explicit member specialization.
202	static bool isExplicitMemberSpecialization(const RedeclarableTemplateDecl *D) {
203	return D->isMemberSpecialization();
204	}
205
206	/// Given a visibility attribute, return the explicit visibility
207	/// associated with it.
208	template <class T>
209	static Visibility getVisibilityFromAttr(const T *attr) {
210	switch (attr->getVisibility()) {
211	case T::Default:
212	return DefaultVisibility;
213	case T::Hidden:
214	return HiddenVisibility;
215	case T::Protected:
216	return ProtectedVisibility;
217	}
218	llvm_unreachable("bad visibility kind");
219	}
220
221	/// Return the explicit visibility of the given declaration.
222	static std::optional<Visibility>
223	getVisibilityOf(const NamedDecl *D, NamedDecl::ExplicitVisibilityKind kind) {
224	// If we're ultimately computing the visibility of a type, look for
225	// a 'type_visibility' attribute before looking for 'visibility'.
226	if (kind == NamedDecl::VisibilityForType) {
227	if (const auto *A = D->getAttr<TypeVisibilityAttr>()) {
228	return getVisibilityFromAttr(A);
229	}
230	}
231
232	// If this declaration has an explicit visibility attribute, use it.
233	if (const auto *A = D->getAttr<VisibilityAttr>()) {
234	return getVisibilityFromAttr(A);
235	}
236
237	return std::nullopt;
238	}
239
240	LinkageInfo LinkageComputer::getLVForType(const Type &T,
241	LVComputationKind computation) {
242	if (computation.IgnoreAllVisibility)
243	return LinkageInfo(T.getLinkage(), DefaultVisibility, true);
244	return getTypeLinkageAndVisibility(T: &T);
245	}
246
247	/// Get the most restrictive linkage for the types in the given
248	/// template parameter list. For visibility purposes, template
249	/// parameters are part of the signature of a template.
250	LinkageInfo LinkageComputer::getLVForTemplateParameterList(
251	const TemplateParameterList *Params, LVComputationKind computation) {
252	LinkageInfo LV;
253	for (const NamedDecl *P : *Params) {
254	// Template type parameters are the most common and never
255	// contribute to visibility, pack or not.
256	if (isa<TemplateTypeParmDecl>(Val: P))
257	continue;
258
259	// Non-type template parameters can be restricted by the value type, e.g.
260	// template <enum X> class A { ... };
261	// We have to be careful here, though, because we can be dealing with
262	// dependent types.
263	if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Val: P)) {
264	// Handle the non-pack case first.
265	if (!NTTP->isExpandedParameterPack()) {
266	if (!NTTP->getType()->isDependentType()) {
267	LV.merge(other: getLVForType(T: *NTTP->getType(), computation));
268	}
269	continue;
270	}
271
272	// Look at all the types in an expanded pack.
273	for (unsigned i = 0, n = NTTP->getNumExpansionTypes(); i != n; ++i) {
274	QualType type = NTTP->getExpansionType(I: i);
275	if (!type->isDependentType())
276	LV.merge(other: getTypeLinkageAndVisibility(T: type));
277	}
278	continue;
279	}
280
281	// Template template parameters can be restricted by their
282	// template parameters, recursively.
283	const auto *TTP = cast<TemplateTemplateParmDecl>(Val: P);
284
285	// Handle the non-pack case first.
286	if (!TTP->isExpandedParameterPack()) {
287	LV.merge(other: getLVForTemplateParameterList(Params: TTP->getTemplateParameters(),
288	computation));
289	continue;
290	}
291
292	// Look at all expansions in an expanded pack.
293	for (unsigned i = 0, n = TTP->getNumExpansionTemplateParameters();
294	i != n; ++i) {
295	LV.merge(other: getLVForTemplateParameterList(
296	Params: TTP->getExpansionTemplateParameters(I: i), computation));
297	}
298	}
299
300	return LV;
301	}
302
303	static const Decl *getOutermostFuncOrBlockContext(const Decl *D) {
304	const Decl *Ret = nullptr;
305	const DeclContext *DC = D->getDeclContext();
306	while (DC->getDeclKind() != Decl::TranslationUnit) {
307	if (isa<FunctionDecl>(Val: DC) || isa<BlockDecl>(Val: DC))
308	Ret = cast<Decl>(Val: DC);
309	DC = DC->getParent();
310	}
311	return Ret;
312	}
313
314	/// Get the most restrictive linkage for the types and
315	/// declarations in the given template argument list.
316	///
317	/// Note that we don't take an LVComputationKind because we always
318	/// want to honor the visibility of template arguments in the same way.
319	LinkageInfo
320	LinkageComputer::getLVForTemplateArgumentList(ArrayRef<TemplateArgument> Args,
321	LVComputationKind computation) {
322	LinkageInfo LV;
323
324	for (const TemplateArgument &Arg : Args) {
325	switch (Arg.getKind()) {
326	case TemplateArgument::Null:
327	case TemplateArgument::Integral:
328	case TemplateArgument::Expression:
329	continue;
330
331	case TemplateArgument::Type:
332	LV.merge(other: getLVForType(T: *Arg.getAsType(), computation));
333	continue;
334
335	case TemplateArgument::Declaration: {
336	const NamedDecl *ND = Arg.getAsDecl();
337	assert(!usesTypeVisibility(ND));
338	LV.merge(other: getLVForDecl(D: ND, computation));
339	continue;
340	}
341
342	case TemplateArgument::NullPtr:
343	LV.merge(other: getTypeLinkageAndVisibility(T: Arg.getNullPtrType()));
344	continue;
345
346	case TemplateArgument::StructuralValue:
347	LV.merge(other: getLVForValue(V: Arg.getAsStructuralValue(), computation));
348	continue;
349
350	case TemplateArgument::Template:
351	case TemplateArgument::TemplateExpansion:
352	if (TemplateDecl *Template =
353	Arg.getAsTemplateOrTemplatePattern().getAsTemplateDecl())
354	LV.merge(other: getLVForDecl(Template, computation));
355	continue;
356
357	case TemplateArgument::Pack:
358	LV.merge(other: getLVForTemplateArgumentList(Args: Arg.getPackAsArray(), computation));
359	continue;
360	}
361	llvm_unreachable("bad template argument kind");
362	}
363
364	return LV;
365	}
366
367	LinkageInfo
368	LinkageComputer::getLVForTemplateArgumentList(const TemplateArgumentList &TArgs,
369	LVComputationKind computation) {
370	return getLVForTemplateArgumentList(Args: TArgs.asArray(), computation);
371	}
372
373	static bool shouldConsiderTemplateVisibility(const FunctionDecl *fn,
374	const FunctionTemplateSpecializationInfo *specInfo) {
375	// Include visibility from the template parameters and arguments
376	// only if this is not an explicit instantiation or specialization
377	// with direct explicit visibility. (Implicit instantiations won't
378	// have a direct attribute.)
379	if (!specInfo->isExplicitInstantiationOrSpecialization())
380	return true;
381
382	return !fn->hasAttr<VisibilityAttr>();
383	}
384
385	/// Merge in template-related linkage and visibility for the given
386	/// function template specialization.
387	///
388	/// We don't need a computation kind here because we can assume
389	/// LVForValue.
390	///
391	/// \param[out] LV the computation to use for the parent
392	void LinkageComputer::mergeTemplateLV(
393	LinkageInfo &LV, const FunctionDecl *fn,
394	const FunctionTemplateSpecializationInfo *specInfo,
395	LVComputationKind computation) {
396	bool considerVisibility =
397	shouldConsiderTemplateVisibility(fn, specInfo);
398
399	FunctionTemplateDecl *temp = specInfo->getTemplate();
400	// Merge information from the template declaration.
401	LinkageInfo tempLV = getLVForDecl(temp, computation);
402	// The linkage of the specialization should be consistent with the
403	// template declaration.
404	LV.setLinkage(tempLV.getLinkage());
405
406	// Merge information from the template parameters.
407	LinkageInfo paramsLV =
408	getLVForTemplateParameterList(Params: temp->getTemplateParameters(), computation);
409	LV.mergeMaybeWithVisibility(other: paramsLV, withVis: considerVisibility);
410
411	// Merge information from the template arguments.
412	const TemplateArgumentList &templateArgs = *specInfo->TemplateArguments;
413	LinkageInfo argsLV = getLVForTemplateArgumentList(TArgs: templateArgs, computation);
414	LV.mergeMaybeWithVisibility(other: argsLV, withVis: considerVisibility);
415	}
416
417	/// Does the given declaration have a direct visibility attribute
418	/// that would match the given rules?
419	static bool hasDirectVisibilityAttribute(const NamedDecl *D,
420	LVComputationKind computation) {
421	if (computation.IgnoreAllVisibility)
422	return false;
423
424	return (computation.isTypeVisibility() && D->hasAttr<TypeVisibilityAttr>()) ||
425	D->hasAttr<VisibilityAttr>();
426	}
427
428	/// Should we consider visibility associated with the template
429	/// arguments and parameters of the given class template specialization?
430	static bool shouldConsiderTemplateVisibility(
431	const ClassTemplateSpecializationDecl *spec,
432	LVComputationKind computation) {
433	// Include visibility from the template parameters and arguments
434	// only if this is not an explicit instantiation or specialization
435	// with direct explicit visibility (and note that implicit
436	// instantiations won't have a direct attribute).
437	//
438	// Furthermore, we want to ignore template parameters and arguments
439	// for an explicit specialization when computing the visibility of a
440	// member thereof with explicit visibility.
441	//
442	// This is a bit complex; let's unpack it.
443	//
444	// An explicit class specialization is an independent, top-level
445	// declaration. As such, if it or any of its members has an
446	// explicit visibility attribute, that must directly express the
447	// user's intent, and we should honor it. The same logic applies to
448	// an explicit instantiation of a member of such a thing.
449
450	// Fast path: if this is not an explicit instantiation or
451	// specialization, we always want to consider template-related
452	// visibility restrictions.
453	if (!spec->isExplicitInstantiationOrSpecialization())
454	return true;
455
456	// This is the 'member thereof' check.
457	if (spec->isExplicitSpecialization() &&
458	hasExplicitVisibilityAlready(computation))
459	return false;
460
461	return !hasDirectVisibilityAttribute(spec, computation);
462	}
463
464	/// Merge in template-related linkage and visibility for the given
465	/// class template specialization.
466	void LinkageComputer::mergeTemplateLV(
467	LinkageInfo &LV, const ClassTemplateSpecializationDecl *spec,
468	LVComputationKind computation) {
469	bool considerVisibility = shouldConsiderTemplateVisibility(spec, computation);
470
471	// Merge information from the template parameters, but ignore
472	// visibility if we're only considering template arguments.
473	ClassTemplateDecl *temp = spec->getSpecializedTemplate();
474	// Merge information from the template declaration.
475	LinkageInfo tempLV = getLVForDecl(temp, computation);
476	// The linkage of the specialization should be consistent with the
477	// template declaration.
478	LV.setLinkage(tempLV.getLinkage());
479
480	LinkageInfo paramsLV =
481	getLVForTemplateParameterList(Params: temp->getTemplateParameters(), computation);
482	LV.mergeMaybeWithVisibility(other: paramsLV,
483	withVis: considerVisibility && !hasExplicitVisibilityAlready(computation));
484
485	// Merge information from the template arguments. We ignore
486	// template-argument visibility if we've got an explicit
487	// instantiation with a visibility attribute.
488	const TemplateArgumentList &templateArgs = spec->getTemplateArgs();
489	LinkageInfo argsLV = getLVForTemplateArgumentList(TArgs: templateArgs, computation);
490	if (considerVisibility)
491	LV.mergeVisibility(other: argsLV);
492	LV.mergeExternalVisibility(Other: argsLV);
493	}
494
495	/// Should we consider visibility associated with the template
496	/// arguments and parameters of the given variable template
497	/// specialization? As usual, follow class template specialization
498	/// logic up to initialization.
499	static bool shouldConsiderTemplateVisibility(
500	const VarTemplateSpecializationDecl *spec,
501	LVComputationKind computation) {
502	// Include visibility from the template parameters and arguments
503	// only if this is not an explicit instantiation or specialization
504	// with direct explicit visibility (and note that implicit
505	// instantiations won't have a direct attribute).
506	if (!spec->isExplicitInstantiationOrSpecialization())
507	return true;
508
509	// An explicit variable specialization is an independent, top-level
510	// declaration. As such, if it has an explicit visibility attribute,
511	// that must directly express the user's intent, and we should honor
512	// it.
513	if (spec->isExplicitSpecialization() &&
514	hasExplicitVisibilityAlready(computation))
515	return false;
516
517	return !hasDirectVisibilityAttribute(spec, computation);
518	}
519
520	/// Merge in template-related linkage and visibility for the given
521	/// variable template specialization. As usual, follow class template
522	/// specialization logic up to initialization.
523	void LinkageComputer::mergeTemplateLV(LinkageInfo &LV,
524	const VarTemplateSpecializationDecl *spec,
525	LVComputationKind computation) {
526	bool considerVisibility = shouldConsiderTemplateVisibility(spec, computation);
527
528	// Merge information from the template parameters, but ignore
529	// visibility if we're only considering template arguments.
530	VarTemplateDecl *temp = spec->getSpecializedTemplate();
531	LinkageInfo tempLV =
532	getLVForTemplateParameterList(Params: temp->getTemplateParameters(), computation);
533	LV.mergeMaybeWithVisibility(other: tempLV,
534	withVis: considerVisibility && !hasExplicitVisibilityAlready(computation));
535
536	// Merge information from the template arguments. We ignore
537	// template-argument visibility if we've got an explicit
538	// instantiation with a visibility attribute.
539	const TemplateArgumentList &templateArgs = spec->getTemplateArgs();
540	LinkageInfo argsLV = getLVForTemplateArgumentList(TArgs: templateArgs, computation);
541	if (considerVisibility)
542	LV.mergeVisibility(other: argsLV);
543	LV.mergeExternalVisibility(Other: argsLV);
544	}
545
546	static bool useInlineVisibilityHidden(const NamedDecl *D) {
547	// FIXME: we should warn if -fvisibility-inlines-hidden is used with c.
548	const LangOptions &Opts = D->getASTContext().getLangOpts();
549	if (!Opts.CPlusPlus || !Opts.InlineVisibilityHidden)
550	return false;
551
552	const auto *FD = dyn_cast<FunctionDecl>(Val: D);
553	if (!FD)
554	return false;
555
556	TemplateSpecializationKind TSK = TSK_Undeclared;
557	if (FunctionTemplateSpecializationInfo *spec
558	= FD->getTemplateSpecializationInfo()) {
559	TSK = spec->getTemplateSpecializationKind();
560	} else if (MemberSpecializationInfo *MSI =
561	FD->getMemberSpecializationInfo()) {
562	TSK = MSI->getTemplateSpecializationKind();
563	}
564
565	const FunctionDecl *Def = nullptr;
566	// InlineVisibilityHidden only applies to definitions, and
567	// isInlined() only gives meaningful answers on definitions
568	// anyway.
569	return TSK != TSK_ExplicitInstantiationDeclaration &&
570	TSK != TSK_ExplicitInstantiationDefinition &&
571	FD->hasBody(Def) && Def->isInlined() && !Def->hasAttr<GNUInlineAttr>();
572	}
573
574	template <typename T> static bool isFirstInExternCContext(T *D) {
575	const T *First = D->getFirstDecl();
576	return First->isInExternCContext();
577	}
578
579	static bool isSingleLineLanguageLinkage(const Decl &D) {
580	if (const auto *SD = dyn_cast<LinkageSpecDecl>(Val: D.getDeclContext()))
581	if (!SD->hasBraces())
582	return true;
583	return false;
584	}
585
586	static bool isDeclaredInModuleInterfaceOrPartition(const NamedDecl *D) {
587	if (auto *M = D->getOwningModule())
588	return M->isInterfaceOrPartition();
589	return false;
590	}
591
592	static LinkageInfo getExternalLinkageFor(const NamedDecl *D) {
593	return LinkageInfo::external();
594	}
595
596	static StorageClass getStorageClass(const Decl *D) {
597	if (auto *TD = dyn_cast<TemplateDecl>(Val: D))
598	D = TD->getTemplatedDecl();
599	if (D) {
600	if (auto *VD = dyn_cast<VarDecl>(Val: D))
601	return VD->getStorageClass();
602	if (auto *FD = dyn_cast<FunctionDecl>(Val: D))
603	return FD->getStorageClass();
604	}
605	return SC_None;
606	}
607
608	LinkageInfo
609	LinkageComputer::getLVForNamespaceScopeDecl(const NamedDecl *D,
610	LVComputationKind computation,
611	bool IgnoreVarTypeLinkage) {
612	assert(D->getDeclContext()->getRedeclContext()->isFileContext() &&
613	"Not a name having namespace scope");
614	ASTContext &Context = D->getASTContext();
615
616	// C++ [basic.link]p3:
617	// A name having namespace scope (3.3.6) has internal linkage if it
618	// is the name of
619
620	if (getStorageClass(D->getCanonicalDecl()) == SC_Static) {
621	// - a variable, variable template, function, or function template
622	// that is explicitly declared static; or
623	// (This bullet corresponds to C99 6.2.2p3.)
624	return LinkageInfo::internal();
625	}
626
627	if (const auto *Var = dyn_cast<VarDecl>(Val: D)) {
628	// - a non-template variable of non-volatile const-qualified type, unless
629	// - it is explicitly declared extern, or
630	// - it is declared in the purview of a module interface unit
631	// (outside the private-module-fragment, if any) or module partition, or
632	// - it is inline, or
633	// - it was previously declared and the prior declaration did not have
634	// internal linkage
635	// (There is no equivalent in C99.)
636	if (Context.getLangOpts().CPlusPlus && Var->getType().isConstQualified() &&
637	!Var->getType().isVolatileQualified() && !Var->isInline() &&
638	!isDeclaredInModuleInterfaceOrPartition(Var) &&
639	!isa<VarTemplateSpecializationDecl>(Val: Var) &&
640	!Var->getDescribedVarTemplate()) {
641	const VarDecl *PrevVar = Var->getPreviousDecl();
642	if (PrevVar)
643	return getLVForDecl(PrevVar, computation);
644
645	if (Var->getStorageClass() != SC_Extern &&
646	Var->getStorageClass() != SC_PrivateExtern &&
647	!isSingleLineLanguageLinkage(*Var))
648	return LinkageInfo::internal();
649	}
650
651	for (const VarDecl *PrevVar = Var->getPreviousDecl(); PrevVar;
652	PrevVar = PrevVar->getPreviousDecl()) {
653	if (PrevVar->getStorageClass() == SC_PrivateExtern &&
654	Var->getStorageClass() == SC_None)
655	return getDeclLinkageAndVisibility(PrevVar);
656	// Explicitly declared static.
657	if (PrevVar->getStorageClass() == SC_Static)
658	return LinkageInfo::internal();
659	}
660	} else if (const auto *IFD = dyn_cast<IndirectFieldDecl>(Val: D)) {
661	// - a data member of an anonymous union.
662	const VarDecl *VD = IFD->getVarDecl();
663	assert(VD && "Expected a VarDecl in this IndirectFieldDecl!");
664	return getLVForNamespaceScopeDecl(VD, computation, IgnoreVarTypeLinkage);
665	}
666	assert(!isa<FieldDecl>(D) && "Didn't expect a FieldDecl!");
667
668	// FIXME: This gives internal linkage to names that should have no linkage
669	// (those not covered by [basic.link]p6).
670	if (D->isInAnonymousNamespace()) {
671	const auto *Var = dyn_cast<VarDecl>(Val: D);
672	const auto *Func = dyn_cast<FunctionDecl>(Val: D);
673	// FIXME: The check for extern "C" here is not justified by the standard
674	// wording, but we retain it from the pre-DR1113 model to avoid breaking
675	// code.
676	//
677	// C++11 [basic.link]p4:
678	// An unnamed namespace or a namespace declared directly or indirectly
679	// within an unnamed namespace has internal linkage.
680	if ((!Var || !isFirstInExternCContext(D: Var)) &&
681	(!Func || !isFirstInExternCContext(D: Func)))
682	return LinkageInfo::internal();
683	}
684
685	// Set up the defaults.
686
687	// C99 6.2.2p5:
688	// If the declaration of an identifier for an object has file
689	// scope and no storage-class specifier, its linkage is
690	// external.
691	LinkageInfo LV = getExternalLinkageFor(D);
692
693	if (!hasExplicitVisibilityAlready(computation)) {
694	if (std::optional<Visibility> Vis = getExplicitVisibility(D, kind: computation)) {
695	LV.mergeVisibility(newVis: *Vis, newExplicit: true);
696	} else {
697	// If we're declared in a namespace with a visibility attribute,
698	// use that namespace's visibility, and it still counts as explicit.
699	for (const DeclContext *DC = D->getDeclContext();
700	!isa<TranslationUnitDecl>(Val: DC);
701	DC = DC->getParent()) {
702	const auto *ND = dyn_cast<NamespaceDecl>(Val: DC);
703	if (!ND) continue;
704	if (std::optional<Visibility> Vis =
705	getExplicitVisibility(ND, computation)) {
706	LV.mergeVisibility(newVis: *Vis, newExplicit: true);
707	break;
708	}
709	}
710	}
711
712	// Add in global settings if the above didn't give us direct visibility.
713	if (!LV.isVisibilityExplicit()) {
714	// Use global type/value visibility as appropriate.
715	Visibility globalVisibility =
716	computation.isValueVisibility()
717	? Context.getLangOpts().getValueVisibilityMode()
718	: Context.getLangOpts().getTypeVisibilityMode();
719	LV.mergeVisibility(newVis: globalVisibility, /*explicit*/ newExplicit: false);
720
721	// If we're paying attention to global visibility, apply
722	// -finline-visibility-hidden if this is an inline method.
723	if (useInlineVisibilityHidden(D))
724	LV.mergeVisibility(newVis: HiddenVisibility, /*visibilityExplicit=*/newExplicit: false);
725	}
726	}
727
728	// C++ [basic.link]p4:
729
730	// A name having namespace scope that has not been given internal linkage
731	// above and that is the name of
732	// [...bullets...]
733	// has its linkage determined as follows:
734	// - if the enclosing namespace has internal linkage, the name has
735	// internal linkage; [handled above]
736	// - otherwise, if the declaration of the name is attached to a named
737	// module and is not exported, the name has module linkage;
738	// - otherwise, the name has external linkage.
739	// LV is currently set up to handle the last two bullets.
740	//
741	// The bullets are:
742
743	// - a variable; or
744	if (const auto *Var = dyn_cast<VarDecl>(Val: D)) {
745	// GCC applies the following optimization to variables and static
746	// data members, but not to functions:
747	//
748	// Modify the variable's LV by the LV of its type unless this is
749	// C or extern "C". This follows from [basic.link]p9:
750	// A type without linkage shall not be used as the type of a
751	// variable or function with external linkage unless
752	// - the entity has C language linkage, or
753	// - the entity is declared within an unnamed namespace, or
754	// - the entity is not used or is defined in the same
755	// translation unit.
756	// and [basic.link]p10:
757	// ...the types specified by all declarations referring to a
758	// given variable or function shall be identical...
759	// C does not have an equivalent rule.
760	//
761	// Ignore this if we've got an explicit attribute; the user
762	// probably knows what they're doing.
763	//
764	// Note that we don't want to make the variable non-external
765	// because of this, but unique-external linkage suits us.
766
767	if (Context.getLangOpts().CPlusPlus && !isFirstInExternCContext(D: Var) &&
768	!IgnoreVarTypeLinkage) {
769	LinkageInfo TypeLV = getLVForType(T: *Var->getType(), computation);
770	if (!isExternallyVisible(L: TypeLV.getLinkage()))
771	return LinkageInfo::uniqueExternal();
772	if (!LV.isVisibilityExplicit())
773	LV.mergeVisibility(other: TypeLV);
774	}
775
776	if (Var->getStorageClass() == SC_PrivateExtern)
777	LV.mergeVisibility(newVis: HiddenVisibility, newExplicit: true);
778
779	// Note that Sema::MergeVarDecl already takes care of implementing
780	// C99 6.2.2p4 and propagating the visibility attribute, so we don't have
781	// to do it here.
782
783	// As per function and class template specializations (below),
784	// consider LV for the template and template arguments. We're at file
785	// scope, so we do not need to worry about nested specializations.
786	if (const auto *spec = dyn_cast<VarTemplateSpecializationDecl>(Val: Var)) {
787	mergeTemplateLV(LV, spec, computation);
788	}
789
790	// - a function; or
791	} else if (const auto *Function = dyn_cast<FunctionDecl>(Val: D)) {
792	// In theory, we can modify the function's LV by the LV of its
793	// type unless it has C linkage (see comment above about variables
794	// for justification). In practice, GCC doesn't do this, so it's
795	// just too painful to make work.
796
797	if (Function->getStorageClass() == SC_PrivateExtern)
798	LV.mergeVisibility(newVis: HiddenVisibility, newExplicit: true);
799
800	// OpenMP target declare device functions are not callable from the host so
801	// they should not be exported from the device image. This applies to all
802	// functions as the host-callable kernel functions are emitted at codegen.
803	if (Context.getLangOpts().OpenMP &&
804	Context.getLangOpts().OpenMPIsTargetDevice &&
805	((Context.getTargetInfo().getTriple().isAMDGPU() ||
806	Context.getTargetInfo().getTriple().isNVPTX()) ||
807	OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Function)))
808	LV.mergeVisibility(newVis: HiddenVisibility, /*newExplicit=*/false);
809
810	// Note that Sema::MergeCompatibleFunctionDecls already takes care of
811	// merging storage classes and visibility attributes, so we don't have to
812	// look at previous decls in here.
813
814	// In C++, then if the type of the function uses a type with
815	// unique-external linkage, it's not legally usable from outside
816	// this translation unit. However, we should use the C linkage
817	// rules instead for extern "C" declarations.
818	if (Context.getLangOpts().CPlusPlus && !isFirstInExternCContext(D: Function)) {
819	// Only look at the type-as-written. Otherwise, deducing the return type
820	// of a function could change its linkage.
821	QualType TypeAsWritten = Function->getType();
822	if (TypeSourceInfo *TSI = Function->getTypeSourceInfo())
823	TypeAsWritten = TSI->getType();
824	if (!isExternallyVisible(L: TypeAsWritten->getLinkage()))
825	return LinkageInfo::uniqueExternal();
826	}
827
828	// Consider LV from the template and the template arguments.
829	// We're at file scope, so we do not need to worry about nested
830	// specializations.
831	if (FunctionTemplateSpecializationInfo *specInfo
832	= Function->getTemplateSpecializationInfo()) {
833	mergeTemplateLV(LV, fn: Function, specInfo, computation);
834	}
835
836	// - a named class (Clause 9), or an unnamed class defined in a
837	// typedef declaration in which the class has the typedef name
838	// for linkage purposes (7.1.3); or
839	// - a named enumeration (7.2), or an unnamed enumeration
840	// defined in a typedef declaration in which the enumeration
841	// has the typedef name for linkage purposes (7.1.3); or
842	} else if (const auto *Tag = dyn_cast<TagDecl>(Val: D)) {
843	// Unnamed tags have no linkage.
844	if (!Tag->hasNameForLinkage())
845	return LinkageInfo::none();
846
847	// If this is a class template specialization, consider the
848	// linkage of the template and template arguments. We're at file
849	// scope, so we do not need to worry about nested specializations.
850	if (const auto *spec = dyn_cast<ClassTemplateSpecializationDecl>(Val: Tag)) {
851	mergeTemplateLV(LV, spec, computation);
852	}
853
854	// FIXME: This is not part of the C++ standard any more.
855	// - an enumerator belonging to an enumeration with external linkage; or
856	} else if (isa<EnumConstantDecl>(Val: D)) {
857	LinkageInfo EnumLV = getLVForDecl(D: cast<NamedDecl>(D->getDeclContext()),
858	computation);
859	if (!isExternalFormalLinkage(L: EnumLV.getLinkage()))
860	return LinkageInfo::none();
861	LV.merge(other: EnumLV);
862
863	// - a template
864	} else if (const auto *temp = dyn_cast<TemplateDecl>(Val: D)) {
865	bool considerVisibility = !hasExplicitVisibilityAlready(computation);
866	LinkageInfo tempLV =
867	getLVForTemplateParameterList(Params: temp->getTemplateParameters(), computation);
868	LV.mergeMaybeWithVisibility(other: tempLV, withVis: considerVisibility);
869
870	// An unnamed namespace or a namespace declared directly or indirectly
871	// within an unnamed namespace has internal linkage. All other namespaces
872	// have external linkage.
873	//
874	// We handled names in anonymous namespaces above.
875	} else if (isa<NamespaceDecl>(Val: D)) {
876	return LV;
877
878	// By extension, we assign external linkage to Objective-C
879	// interfaces.
880	} else if (isa<ObjCInterfaceDecl>(Val: D)) {
881	// fallout
882
883	} else if (auto *TD = dyn_cast<TypedefNameDecl>(Val: D)) {
884	// A typedef declaration has linkage if it gives a type a name for
885	// linkage purposes.
886	if (!TD->getAnonDeclWithTypedefName(/*AnyRedecl*/true))
887	return LinkageInfo::none();
888
889	} else if (isa<MSGuidDecl>(Val: D)) {
890	// A GUID behaves like an inline variable with external linkage. Fall
891	// through.
892
893	// Everything not covered here has no linkage.
894	} else {
895	return LinkageInfo::none();
896	}
897
898	// If we ended up with non-externally-visible linkage, visibility should
899	// always be default.
900	if (!isExternallyVisible(L: LV.getLinkage()))
901	return LinkageInfo(LV.getLinkage(), DefaultVisibility, false);
902
903	return LV;
904	}
905
906	LinkageInfo
907	LinkageComputer::getLVForClassMember(const NamedDecl *D,
908	LVComputationKind computation,
909	bool IgnoreVarTypeLinkage) {
910	// Only certain class members have linkage. Note that fields don't
911	// really have linkage, but it's convenient to say they do for the
912	// purposes of calculating linkage of pointer-to-data-member
913	// template arguments.
914	//
915	// Templates also don't officially have linkage, but since we ignore
916	// the C++ standard and look at template arguments when determining
917	// linkage and visibility of a template specialization, we might hit
918	// a template template argument that way. If we do, we need to
919	// consider its linkage.
920	if (!(isa<CXXMethodDecl>(Val: D) ||
921	isa<VarDecl>(Val: D) ||
922	isa<FieldDecl>(Val: D) ||
923	isa<IndirectFieldDecl>(Val: D) ||
924	isa<TagDecl>(Val: D) ||
925	isa<TemplateDecl>(Val: D)))
926	return LinkageInfo::none();
927
928	LinkageInfo LV;
929
930	// If we have an explicit visibility attribute, merge that in.
931	if (!hasExplicitVisibilityAlready(computation)) {
932	if (std::optional<Visibility> Vis = getExplicitVisibility(D, kind: computation))
933	LV.mergeVisibility(newVis: *Vis, newExplicit: true);
934	// If we're paying attention to global visibility, apply
935	// -finline-visibility-hidden if this is an inline method.
936	//
937	// Note that we do this before merging information about
938	// the class visibility.
939	if (!LV.isVisibilityExplicit() && useInlineVisibilityHidden(D))
940	LV.mergeVisibility(newVis: HiddenVisibility, /*visibilityExplicit=*/newExplicit: false);
941	}
942
943	// If this class member has an explicit visibility attribute, the only
944	// thing that can change its visibility is the template arguments, so
945	// only look for them when processing the class.
946	LVComputationKind classComputation = computation;
947	if (LV.isVisibilityExplicit())
948	classComputation = withExplicitVisibilityAlready(Kind: computation);
949
950	LinkageInfo classLV =
951	getLVForDecl(D: cast<RecordDecl>(D->getDeclContext()), computation: classComputation);
952	// The member has the same linkage as the class. If that's not externally
953	// visible, we don't need to compute anything about the linkage.
954	// FIXME: If we're only computing linkage, can we bail out here?
955	if (!isExternallyVisible(L: classLV.getLinkage()))
956	return classLV;
957
958
959	// Otherwise, don't merge in classLV yet, because in certain cases
960	// we need to completely ignore the visibility from it.
961
962	// Specifically, if this decl exists and has an explicit attribute.
963	const NamedDecl *explicitSpecSuppressor = nullptr;
964
965	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: D)) {
966	// Only look at the type-as-written. Otherwise, deducing the return type
967	// of a function could change its linkage.
968	QualType TypeAsWritten = MD->getType();
969	if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
970	TypeAsWritten = TSI->getType();
971	if (!isExternallyVisible(L: TypeAsWritten->getLinkage()))
972	return LinkageInfo::uniqueExternal();
973
974	// If this is a method template specialization, use the linkage for
975	// the template parameters and arguments.
976	if (FunctionTemplateSpecializationInfo *spec
977	= MD->getTemplateSpecializationInfo()) {
978	mergeTemplateLV(LV, MD, spec, computation);
979	if (spec->isExplicitSpecialization()) {
980	explicitSpecSuppressor = MD;
981	} else if (isExplicitMemberSpecialization(spec->getTemplate())) {
982	explicitSpecSuppressor = spec->getTemplate()->getTemplatedDecl();
983	}
984	} else if (isExplicitMemberSpecialization(D: MD)) {
985	explicitSpecSuppressor = MD;
986	}
987
988	// OpenMP target declare device functions are not callable from the host so
989	// they should not be exported from the device image. This applies to all
990	// functions as the host-callable kernel functions are emitted at codegen.
991	ASTContext &Context = D->getASTContext();
992	if (Context.getLangOpts().OpenMP &&
993	Context.getLangOpts().OpenMPIsTargetDevice &&
994	((Context.getTargetInfo().getTriple().isAMDGPU() ||
995	Context.getTargetInfo().getTriple().isNVPTX()) ||
996	OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(MD)))
997	LV.mergeVisibility(newVis: HiddenVisibility, /*newExplicit=*/false);
998
999	} else if (const auto *RD = dyn_cast<CXXRecordDecl>(Val: D)) {
1000	if (const auto *spec = dyn_cast<ClassTemplateSpecializationDecl>(Val: RD)) {
1001	mergeTemplateLV(LV, spec, computation);
1002	if (spec->isExplicitSpecialization()) {
1003	explicitSpecSuppressor = spec;
1004	} else {
1005	const ClassTemplateDecl *temp = spec->getSpecializedTemplate();
1006	if (isExplicitMemberSpecialization(temp)) {
1007	explicitSpecSuppressor = temp->getTemplatedDecl();
1008	}
1009	}
1010	} else if (isExplicitMemberSpecialization(D: RD)) {
1011	explicitSpecSuppressor = RD;
1012	}
1013
1014	// Static data members.
1015	} else if (const auto *VD = dyn_cast<VarDecl>(Val: D)) {
1016	if (const auto *spec = dyn_cast<VarTemplateSpecializationDecl>(Val: VD))
1017	mergeTemplateLV(LV, spec, computation);
1018
1019	// Modify the variable's linkage by its type, but ignore the
1020	// type's visibility unless it's a definition.
1021	if (!IgnoreVarTypeLinkage) {
1022	LinkageInfo typeLV = getLVForType(T: *VD->getType(), computation);
1023	// FIXME: If the type's linkage is not externally visible, we can
1024	// give this static data member UniqueExternalLinkage.
1025	if (!LV.isVisibilityExplicit() && !classLV.isVisibilityExplicit())
1026	LV.mergeVisibility(other: typeLV);
1027	LV.mergeExternalVisibility(Other: typeLV);
1028	}
1029
1030	if (isExplicitMemberSpecialization(D: VD)) {
1031	explicitSpecSuppressor = VD;
1032	}
1033
1034	// Template members.
1035	} else if (const auto *temp = dyn_cast<TemplateDecl>(Val: D)) {
1036	bool considerVisibility =
1037	(!LV.isVisibilityExplicit() &&
1038	!classLV.isVisibilityExplicit() &&
1039	!hasExplicitVisibilityAlready(computation));
1040	LinkageInfo tempLV =
1041	getLVForTemplateParameterList(Params: temp->getTemplateParameters(), computation);
1042	LV.mergeMaybeWithVisibility(other: tempLV, withVis: considerVisibility);
1043
1044	if (const auto *redeclTemp = dyn_cast<RedeclarableTemplateDecl>(Val: temp)) {
1045	if (isExplicitMemberSpecialization(D: redeclTemp)) {
1046	explicitSpecSuppressor = temp->getTemplatedDecl();
1047	}
1048	}
1049	}
1050
1051	// We should never be looking for an attribute directly on a template.
1052	assert(!explicitSpecSuppressor || !isa<TemplateDecl>(explicitSpecSuppressor));
1053
1054	// If this member is an explicit member specialization, and it has
1055	// an explicit attribute, ignore visibility from the parent.
1056	bool considerClassVisibility = true;
1057	if (explicitSpecSuppressor &&
1058	// optimization: hasDVA() is true only with explicit visibility.
1059	LV.isVisibilityExplicit() &&
1060	classLV.getVisibility() != DefaultVisibility &&
1061	hasDirectVisibilityAttribute(D: explicitSpecSuppressor, computation)) {
1062	considerClassVisibility = false;
1063	}
1064
1065	// Finally, merge in information from the class.
1066	LV.mergeMaybeWithVisibility(other: classLV, withVis: considerClassVisibility);
1067	return LV;
1068	}
1069
1070	void NamedDecl::anchor() {}
1071
1072	bool NamedDecl::isLinkageValid() const {
1073	if (!hasCachedLinkage())
1074	return true;
1075
1076	Linkage L = LinkageComputer{}
1077	.computeLVForDecl(D: this, computation: LVComputationKind::forLinkageOnly())
1078	.getLinkage();
1079	return L == getCachedLinkage();
1080	}
1081
1082	bool NamedDecl::isPlaceholderVar(const LangOptions &LangOpts) const {
1083	// [C++2c] [basic.scope.scope]/p5
1084	// A declaration is name-independent if its name is _ and it declares
1085	// - a variable with automatic storage duration,
1086	// - a structured binding not inhabiting a namespace scope,
1087	// - the variable introduced by an init-capture
1088	// - or a non-static data member.
1089
1090	if (!LangOpts.CPlusPlus || !getIdentifier() ||
1091	!getIdentifier()->isPlaceholder())
1092	return false;
1093	if (isa<FieldDecl>(Val: this))
1094	return true;
1095	if (const auto *IFD = dyn_cast<IndirectFieldDecl>(Val: this)) {
1096	if (!getDeclContext()->isFunctionOrMethod() &&
1097	!getDeclContext()->isRecord())
1098	return false;
1099	const VarDecl *VD = IFD->getVarDecl();
1100	return !VD || VD->getStorageDuration() == SD_Automatic;
1101	}
1102	// and it declares a variable with automatic storage duration
1103	if (const auto *VD = dyn_cast<VarDecl>(Val: this)) {
1104	if (isa<ParmVarDecl>(Val: VD))
1105	return false;
1106	if (VD->isInitCapture())
1107	return true;
1108	return VD->getStorageDuration() == StorageDuration::SD_Automatic;
1109	}
1110	if (const auto *BD = dyn_cast<BindingDecl>(Val: this);
1111	BD && getDeclContext()->isFunctionOrMethod()) {
1112	const VarDecl *VD = BD->getHoldingVar();
1113	return !VD || VD->getStorageDuration() == StorageDuration::SD_Automatic;
1114	}
1115	return false;
1116	}
1117
1118	ReservedIdentifierStatus
1119	NamedDecl::isReserved(const LangOptions &LangOpts) const {
1120	const IdentifierInfo *II = getIdentifier();
1121
1122	// This triggers at least for CXXLiteralIdentifiers, which we already checked
1123	// at lexing time.
1124	if (!II)
1125	return ReservedIdentifierStatus::NotReserved;
1126
1127	ReservedIdentifierStatus Status = II->isReserved(LangOpts);
1128	if (isReservedAtGlobalScope(Status) && !isReservedInAllContexts(Status)) {
1129	// This name is only reserved at global scope. Check if this declaration
1130	// conflicts with a global scope declaration.
1131	if (isa<ParmVarDecl>(Val: this) || isTemplateParameter())
1132	return ReservedIdentifierStatus::NotReserved;
1133
1134	// C++ [dcl.link]/7:
1135	// Two declarations [conflict] if [...] one declares a function or
1136	// variable with C language linkage, and the other declares [...] a
1137	// variable that belongs to the global scope.
1138	//
1139	// Therefore names that are reserved at global scope are also reserved as
1140	// names of variables and functions with C language linkage.
1141	const DeclContext *DC = getDeclContext()->getRedeclContext();
1142	if (DC->isTranslationUnit())
1143	return Status;
1144	if (auto *VD = dyn_cast<VarDecl>(Val: this))
1145	if (VD->isExternC())
1146	return ReservedIdentifierStatus::StartsWithUnderscoreAndIsExternC;
1147	if (auto *FD = dyn_cast<FunctionDecl>(Val: this))
1148	if (FD->isExternC())
1149	return ReservedIdentifierStatus::StartsWithUnderscoreAndIsExternC;
1150	return ReservedIdentifierStatus::NotReserved;
1151	}
1152
1153	return Status;
1154	}
1155
1156	ObjCStringFormatFamily NamedDecl::getObjCFStringFormattingFamily() const {
1157	StringRef name = getName();
1158	if (name.empty()) return SFF_None;
1159
1160	if (name.front() == 'C')
1161	if (name == "CFStringCreateWithFormat" ||
1162	name == "CFStringCreateWithFormatAndArguments" ||
1163	name == "CFStringAppendFormat" ||
1164	name == "CFStringAppendFormatAndArguments")
1165	return SFF_CFString;
1166	return SFF_None;
1167	}
1168
1169	Linkage NamedDecl::getLinkageInternal() const {
1170	// We don't care about visibility here, so ask for the cheapest
1171	// possible visibility analysis.
1172	return LinkageComputer{}
1173	.getLVForDecl(D: this, computation: LVComputationKind::forLinkageOnly())
1174	.getLinkage();
1175	}
1176
1177	/// Determine whether D is attached to a named module.
1178	static bool isInNamedModule(const NamedDecl *D) {
1179	if (auto *M = D->getOwningModule())
1180	return M->isNamedModule();
1181	return false;
1182	}
1183
1184	static bool isExportedFromModuleInterfaceUnit(const NamedDecl *D) {
1185	// FIXME: Handle isModulePrivate.
1186	switch (D->getModuleOwnershipKind()) {
1187	case Decl::ModuleOwnershipKind::Unowned:
1188	case Decl::ModuleOwnershipKind::ReachableWhenImported:
1189	case Decl::ModuleOwnershipKind::ModulePrivate:
1190	return false;
1191	case Decl::ModuleOwnershipKind::Visible:
1192	case Decl::ModuleOwnershipKind::VisibleWhenImported:
1193	return isInNamedModule(D);
1194	}
1195	llvm_unreachable("unexpected module ownership kind");
1196	}
1197
1198	/// Get the linkage from a semantic point of view. Entities in
1199	/// anonymous namespaces are external (in c++98).
1200	Linkage NamedDecl::getFormalLinkage() const {
1201	Linkage InternalLinkage = getLinkageInternal();
1202
1203	// C++ [basic.link]p4.8:
1204	// - if the declaration of the name is attached to a named module and is not
1205	// exported
1206	// the name has module linkage;
1207	//
1208	// [basic.namespace.general]/p2
1209	// A namespace is never attached to a named module and never has a name with
1210	// module linkage.
1211	if (isInNamedModule(D: this) && InternalLinkage == Linkage::External &&
1212	!isExportedFromModuleInterfaceUnit(
1213	cast<NamedDecl>(this->getCanonicalDecl())) &&
1214	!isa<NamespaceDecl>(Val: this))
1215	InternalLinkage = Linkage::Module;
1216
1217	return clang::getFormalLinkage(L: InternalLinkage);
1218	}
1219
1220	LinkageInfo NamedDecl::getLinkageAndVisibility() const {
1221	return LinkageComputer{}.getDeclLinkageAndVisibility(D: this);
1222	}
1223
1224	static std::optional<Visibility>
1225	getExplicitVisibilityAux(const NamedDecl *ND,
1226	NamedDecl::ExplicitVisibilityKind kind,
1227	bool IsMostRecent) {
1228	assert(!IsMostRecent || ND == ND->getMostRecentDecl());
1229
1230	// Check the declaration itself first.
1231	if (std::optional<Visibility> V = getVisibilityOf(D: ND, kind))
1232	return V;
1233
1234	// If this is a member class of a specialization of a class template
1235	// and the corresponding decl has explicit visibility, use that.
1236	if (const auto *RD = dyn_cast<CXXRecordDecl>(Val: ND)) {
1237	CXXRecordDecl *InstantiatedFrom = RD->getInstantiatedFromMemberClass();
1238	if (InstantiatedFrom)
1239	return getVisibilityOf(InstantiatedFrom, kind);
1240	}
1241
1242	// If there wasn't explicit visibility there, and this is a
1243	// specialization of a class template, check for visibility
1244	// on the pattern.
1245	if (const auto *spec = dyn_cast<ClassTemplateSpecializationDecl>(Val: ND)) {
1246	// Walk all the template decl till this point to see if there are
1247	// explicit visibility attributes.
1248	const auto *TD = spec->getSpecializedTemplate()->getTemplatedDecl();
1249	while (TD != nullptr) {
1250	auto Vis = getVisibilityOf(TD, kind);
1251	if (Vis != std::nullopt)
1252	return Vis;
1253	TD = TD->getPreviousDecl();
1254	}
1255	return std::nullopt;
1256	}
1257
1258	// Use the most recent declaration.
1259	if (!IsMostRecent && !isa<NamespaceDecl>(Val: ND)) {
1260	const NamedDecl *MostRecent = ND->getMostRecentDecl();
1261	if (MostRecent != ND)
1262	return getExplicitVisibilityAux(ND: MostRecent, kind, IsMostRecent: true);
1263	}
1264
1265	if (const auto *Var = dyn_cast<VarDecl>(Val: ND)) {
1266	if (Var->isStaticDataMember()) {
1267	VarDecl *InstantiatedFrom = Var->getInstantiatedFromStaticDataMember();
1268	if (InstantiatedFrom)
1269	return getVisibilityOf(InstantiatedFrom, kind);
1270	}
1271
1272	if (const auto *VTSD = dyn_cast<VarTemplateSpecializationDecl>(Val: Var))
1273	return getVisibilityOf(VTSD->getSpecializedTemplate()->getTemplatedDecl(),
1274	kind);
1275
1276	return std::nullopt;
1277	}
1278	// Also handle function template specializations.
1279	if (const auto *fn = dyn_cast<FunctionDecl>(Val: ND)) {
1280	// If the function is a specialization of a template with an
1281	// explicit visibility attribute, use that.
1282	if (FunctionTemplateSpecializationInfo *templateInfo
1283	= fn->getTemplateSpecializationInfo())
1284	return getVisibilityOf(templateInfo->getTemplate()->getTemplatedDecl(),
1285	kind);
1286
1287	// If the function is a member of a specialization of a class template
1288	// and the corresponding decl has explicit visibility, use that.
1289	FunctionDecl *InstantiatedFrom = fn->getInstantiatedFromMemberFunction();
1290	if (InstantiatedFrom)
1291	return getVisibilityOf(InstantiatedFrom, kind);
1292
1293	return std::nullopt;
1294	}
1295
1296	// The visibility of a template is stored in the templated decl.
1297	if (const auto *TD = dyn_cast<TemplateDecl>(Val: ND))
1298	return getVisibilityOf(D: TD->getTemplatedDecl(), kind);
1299
1300	return std::nullopt;
1301	}
1302
1303	std::optional<Visibility>
1304	NamedDecl::getExplicitVisibility(ExplicitVisibilityKind kind) const {
1305	return getExplicitVisibilityAux(ND: this, kind, IsMostRecent: false);
1306	}
1307
1308	LinkageInfo LinkageComputer::getLVForClosure(const DeclContext *DC,
1309	Decl *ContextDecl,
1310	LVComputationKind computation) {
1311	// This lambda has its linkage/visibility determined by its owner.
1312	const NamedDecl *Owner;
1313	if (!ContextDecl)
1314	Owner = dyn_cast<NamedDecl>(Val: DC);
1315	else if (isa<ParmVarDecl>(Val: ContextDecl))
1316	Owner =
1317	dyn_cast<NamedDecl>(Val: ContextDecl->getDeclContext()->getRedeclContext());
1318	else if (isa<ImplicitConceptSpecializationDecl>(Val: ContextDecl)) {
1319	// Replace with the concept's owning decl, which is either a namespace or a
1320	// TU, so this needs a dyn_cast.
1321	Owner = dyn_cast<NamedDecl>(Val: ContextDecl->getDeclContext());
1322	} else {
1323	Owner = cast<NamedDecl>(Val: ContextDecl);
1324	}
1325
1326	if (!Owner)
1327	return LinkageInfo::none();
1328
1329	// If the owner has a deduced type, we need to skip querying the linkage and
1330	// visibility of that type, because it might involve this closure type. The
1331	// only effect of this is that we might give a lambda VisibleNoLinkage rather
1332	// than NoLinkage when we don't strictly need to, which is benign.
1333	auto *VD = dyn_cast<VarDecl>(Val: Owner);
1334	LinkageInfo OwnerLV =
1335	VD && VD->getType()->getContainedDeducedType()
1336	? computeLVForDecl(D: Owner, computation, /*IgnoreVarTypeLinkage*/true)
1337	: getLVForDecl(D: Owner, computation);
1338
1339	// A lambda never formally has linkage. But if the owner is externally
1340	// visible, then the lambda is too. We apply the same rules to blocks.
1341	if (!isExternallyVisible(L: OwnerLV.getLinkage()))
1342	return LinkageInfo::none();
1343	return LinkageInfo(Linkage::VisibleNone, OwnerLV.getVisibility(),
1344	OwnerLV.isVisibilityExplicit());
1345	}
1346
1347	LinkageInfo LinkageComputer::getLVForLocalDecl(const NamedDecl *D,
1348	LVComputationKind computation) {
1349	if (const auto *Function = dyn_cast<FunctionDecl>(Val: D)) {
1350	if (Function->isInAnonymousNamespace() &&
1351	!isFirstInExternCContext(D: Function))
1352	return LinkageInfo::internal();
1353
1354	// This is a "void f();" which got merged with a file static.
1355	if (Function->getCanonicalDecl()->getStorageClass() == SC_Static)
1356	return LinkageInfo::internal();
1357
1358	LinkageInfo LV;
1359	if (!hasExplicitVisibilityAlready(computation)) {
1360	if (std::optional<Visibility> Vis =
1361	getExplicitVisibility(Function, computation))
1362	LV.mergeVisibility(newVis: *Vis, newExplicit: true);
1363	}
1364
1365	// Note that Sema::MergeCompatibleFunctionDecls already takes care of
1366	// merging storage classes and visibility attributes, so we don't have to
1367	// look at previous decls in here.
1368
1369	return LV;
1370	}
1371
1372	if (const auto *Var = dyn_cast<VarDecl>(Val: D)) {
1373	if (Var->hasExternalStorage()) {
1374	if (Var->isInAnonymousNamespace() && !isFirstInExternCContext(D: Var))
1375	return LinkageInfo::internal();
1376
1377	LinkageInfo LV;
1378	if (Var->getStorageClass() == SC_PrivateExtern)
1379	LV.mergeVisibility(newVis: HiddenVisibility, newExplicit: true);
1380	else if (!hasExplicitVisibilityAlready(computation)) {
1381	if (std::optional<Visibility> Vis =
1382	getExplicitVisibility(Var, computation))
1383	LV.mergeVisibility(newVis: *Vis, newExplicit: true);
1384	}
1385
1386	if (const VarDecl *Prev = Var->getPreviousDecl()) {
1387	LinkageInfo PrevLV = getLVForDecl(Prev, computation);
1388	if (PrevLV.getLinkage() != Linkage::Invalid)
1389	LV.setLinkage(PrevLV.getLinkage());
1390	LV.mergeVisibility(other: PrevLV);
1391	}
1392
1393	return LV;
1394	}
1395
1396	if (!Var->isStaticLocal())
1397	return LinkageInfo::none();
1398	}
1399
1400	ASTContext &Context = D->getASTContext();
1401	if (!Context.getLangOpts().CPlusPlus)
1402	return LinkageInfo::none();
1403
1404	const Decl *OuterD = getOutermostFuncOrBlockContext(D);
1405	if (!OuterD || OuterD->isInvalidDecl())
1406	return LinkageInfo::none();
1407
1408	LinkageInfo LV;
1409	if (const auto *BD = dyn_cast<BlockDecl>(OuterD)) {
1410	if (!BD->getBlockManglingNumber())
1411	return LinkageInfo::none();
1412
1413	LV = getLVForClosure(DC: BD->getDeclContext()->getRedeclContext(),
1414	ContextDecl: BD->getBlockManglingContextDecl(), computation);
1415	} else {
1416	const auto *FD = cast<FunctionDecl>(Val: OuterD);
1417	if (!FD->isInlined() &&
1418	!isTemplateInstantiation(FD->getTemplateSpecializationKind()))
1419	return LinkageInfo::none();
1420
1421	// If a function is hidden by -fvisibility-inlines-hidden option and
1422	// is not explicitly attributed as a hidden function,
1423	// we should not make static local variables in the function hidden.
1424	LV = getLVForDecl(D: FD, computation);
1425	if (isa<VarDecl>(Val: D) && useInlineVisibilityHidden(FD) &&
1426	!LV.isVisibilityExplicit() &&
1427	!Context.getLangOpts().VisibilityInlinesHiddenStaticLocalVar) {
1428	assert(cast<VarDecl>(D)->isStaticLocal());
1429	// If this was an implicitly hidden inline method, check again for
1430	// explicit visibility on the parent class, and use that for static locals
1431	// if present.
1432	if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
1433	LV = getLVForDecl(D: MD->getParent(), computation);
1434	if (!LV.isVisibilityExplicit()) {
1435	Visibility globalVisibility =
1436	computation.isValueVisibility()
1437	? Context.getLangOpts().getValueVisibilityMode()
1438	: Context.getLangOpts().getTypeVisibilityMode();
1439	return LinkageInfo(Linkage::VisibleNone, globalVisibility,
1440	/*visibilityExplicit=*/false);
1441	}
1442	}
1443	}
1444	if (!isExternallyVisible(L: LV.getLinkage()))
1445	return LinkageInfo::none();
1446	return LinkageInfo(Linkage::VisibleNone, LV.getVisibility(),
1447	LV.isVisibilityExplicit());
1448	}
1449
1450	LinkageInfo LinkageComputer::computeLVForDecl(const NamedDecl *D,
1451	LVComputationKind computation,
1452	bool IgnoreVarTypeLinkage) {
1453	// Internal_linkage attribute overrides other considerations.
1454	if (D->hasAttr<InternalLinkageAttr>())
1455	return LinkageInfo::internal();
1456
1457	// Objective-C: treat all Objective-C declarations as having external
1458	// linkage.
1459	switch (D->getKind()) {
1460	default:
1461	break;
1462
1463	// Per C++ [basic.link]p2, only the names of objects, references,
1464	// functions, types, templates, namespaces, and values ever have linkage.
1465	//
1466	// Note that the name of a typedef, namespace alias, using declaration,
1467	// and so on are not the name of the corresponding type, namespace, or
1468	// declaration, so they do *not* have linkage.
1469	case Decl::ImplicitParam:
1470	case Decl::Label:
1471	case Decl::NamespaceAlias:
1472	case Decl::ParmVar:
1473	case Decl::Using:
1474	case Decl::UsingEnum:
1475	case Decl::UsingShadow:
1476	case Decl::UsingDirective:
1477	return LinkageInfo::none();
1478
1479	case Decl::EnumConstant:
1480	// C++ [basic.link]p4: an enumerator has the linkage of its enumeration.
1481	if (D->getASTContext().getLangOpts().CPlusPlus)
1482	return getLVForDecl(D: cast<EnumDecl>(D->getDeclContext()), computation);
1483	return LinkageInfo::visible_none();
1484
1485	case Decl::Typedef:
1486	case Decl::TypeAlias:
1487	// A typedef declaration has linkage if it gives a type a name for
1488	// linkage purposes.
1489	if (!cast<TypedefNameDecl>(Val: D)
1490	->getAnonDeclWithTypedefName(/*AnyRedecl*/true))
1491	return LinkageInfo::none();
1492	break;
1493
1494	case Decl::TemplateTemplateParm: // count these as external
1495	case Decl::NonTypeTemplateParm:
1496	case Decl::ObjCAtDefsField:
1497	case Decl::ObjCCategory:
1498	case Decl::ObjCCategoryImpl:
1499	case Decl::ObjCCompatibleAlias:
1500	case Decl::ObjCImplementation:
1501	case Decl::ObjCMethod:
1502	case Decl::ObjCProperty:
1503	case Decl::ObjCPropertyImpl:
1504	case Decl::ObjCProtocol:
1505	return getExternalLinkageFor(D);
1506
1507	case Decl::CXXRecord: {
1508	const auto *Record = cast<CXXRecordDecl>(Val: D);
1509	if (Record->isLambda()) {
1510	if (Record->hasKnownLambdaInternalLinkage() ||
1511	!Record->getLambdaManglingNumber()) {
1512	// This lambda has no mangling number, so it's internal.
1513	return LinkageInfo::internal();
1514	}
1515
1516	return getLVForClosure(
1517	DC: Record->getDeclContext()->getRedeclContext(),
1518	ContextDecl: Record->getLambdaContextDecl(), computation);
1519	}
1520
1521	break;
1522	}
1523
1524	case Decl::TemplateParamObject: {
1525	// The template parameter object can be referenced from anywhere its type
1526	// and value can be referenced.
1527	auto *TPO = cast<TemplateParamObjectDecl>(Val: D);
1528	LinkageInfo LV = getLVForType(T: *TPO->getType(), computation);
1529	LV.merge(other: getLVForValue(V: TPO->getValue(), computation));
1530	return LV;
1531	}
1532	}
1533
1534	// Handle linkage for namespace-scope names.
1535	if (D->getDeclContext()->getRedeclContext()->isFileContext())
1536	return getLVForNamespaceScopeDecl(D, computation, IgnoreVarTypeLinkage);
1537
1538	// C++ [basic.link]p5:
1539	// In addition, a member function, static data member, a named
1540	// class or enumeration of class scope, or an unnamed class or
1541	// enumeration defined in a class-scope typedef declaration such
1542	// that the class or enumeration has the typedef name for linkage
1543	// purposes (7.1.3), has external linkage if the name of the class
1544	// has external linkage.
1545	if (D->getDeclContext()->isRecord())
1546	return getLVForClassMember(D, computation, IgnoreVarTypeLinkage);
1547
1548	// C++ [basic.link]p6:
1549	// The name of a function declared in block scope and the name of
1550	// an object declared by a block scope extern declaration have
1551	// linkage. If there is a visible declaration of an entity with
1552	// linkage having the same name and type, ignoring entities
1553	// declared outside the innermost enclosing namespace scope, the
1554	// block scope declaration declares that same entity and receives
1555	// the linkage of the previous declaration. If there is more than
1556	// one such matching entity, the program is ill-formed. Otherwise,
1557	// if no matching entity is found, the block scope entity receives
1558	// external linkage.
1559	if (D->getDeclContext()->isFunctionOrMethod())
1560	return getLVForLocalDecl(D, computation);
1561
1562	// C++ [basic.link]p6:
1563	// Names not covered by these rules have no linkage.
1564	return LinkageInfo::none();
1565	}
1566
1567	/// getLVForDecl - Get the linkage and visibility for the given declaration.
1568	LinkageInfo LinkageComputer::getLVForDecl(const NamedDecl *D,
1569	LVComputationKind computation) {
1570	// Internal_linkage attribute overrides other considerations.
1571	if (D->hasAttr<InternalLinkageAttr>())
1572	return LinkageInfo::internal();
1573
1574	if (computation.IgnoreAllVisibility && D->hasCachedLinkage())
1575	return LinkageInfo(D->getCachedLinkage(), DefaultVisibility, false);
1576
1577	if (std::optional<LinkageInfo> LI = lookup(ND: D, Kind: computation))
1578	return *LI;
1579
1580	LinkageInfo LV = computeLVForDecl(D, computation);
1581	if (D->hasCachedLinkage())
1582	assert(D->getCachedLinkage() == LV.getLinkage());
1583
1584	D->setCachedLinkage(LV.getLinkage());
1585	cache(ND: D, Kind: computation, Info: LV);
1586
1587	#ifndef NDEBUG
1588	// In C (because of gnu inline) and in c++ with microsoft extensions an
1589	// static can follow an extern, so we can have two decls with different
1590	// linkages.
1591	const LangOptions &Opts = D->getASTContext().getLangOpts();
1592	if (!Opts.CPlusPlus || Opts.MicrosoftExt)
1593	return LV;
1594
1595	// We have just computed the linkage for this decl. By induction we know
1596	// that all other computed linkages match, check that the one we just
1597	// computed also does.
1598	NamedDecl *Old = nullptr;
1599	for (auto *I : D->redecls()) {
1600	auto *T = cast<NamedDecl>(I);
1601	if (T == D)
1602	continue;
1603	if (!T->isInvalidDecl() && T->hasCachedLinkage()) {
1604	Old = T;
1605	break;
1606	}
1607	}
1608	assert(!Old || Old->getCachedLinkage() == D->getCachedLinkage());
1609	#endif
1610
1611	return LV;
1612	}
1613
1614	LinkageInfo LinkageComputer::getDeclLinkageAndVisibility(const NamedDecl *D) {
1615	NamedDecl::ExplicitVisibilityKind EK = usesTypeVisibility(D)
1616	? NamedDecl::VisibilityForType
1617	: NamedDecl::VisibilityForValue;
1618	LVComputationKind CK(EK);
1619	return getLVForDecl(D, computation: D->getASTContext().getLangOpts().IgnoreXCOFFVisibility
1620	? CK.forLinkageOnly()
1621	: CK);
1622	}
1623
1624	Module *Decl::getOwningModuleForLinkage(bool IgnoreLinkage) const {
1625	if (isa<NamespaceDecl>(Val: this))
1626	// Namespaces never have module linkage. It is the entities within them
1627	// that [may] do.
1628	return nullptr;
1629
1630	Module *M = getOwningModule();
1631	if (!M)
1632	return nullptr;
1633
1634	switch (M->Kind) {
1635	case Module::ModuleMapModule:
1636	// Module map modules have no special linkage semantics.
1637	return nullptr;
1638
1639	case Module::ModuleInterfaceUnit:
1640	case Module::ModuleImplementationUnit:
1641	case Module::ModulePartitionInterface:
1642	case Module::ModulePartitionImplementation:
1643	return M;
1644
1645	case Module::ModuleHeaderUnit:
1646	case Module::ExplicitGlobalModuleFragment:
1647	case Module::ImplicitGlobalModuleFragment: {
1648	// External linkage declarations in the global module have no owning module
1649	// for linkage purposes. But internal linkage declarations in the global
1650	// module fragment of a particular module are owned by that module for
1651	// linkage purposes.
1652	// FIXME: p1815 removes the need for this distinction -- there are no
1653	// internal linkage declarations that need to be referred to from outside
1654	// this TU.
1655	if (IgnoreLinkage)
1656	return nullptr;
1657	bool InternalLinkage;
1658	if (auto *ND = dyn_cast<NamedDecl>(Val: this))
1659	InternalLinkage = !ND->hasExternalFormalLinkage();
1660	else
1661	InternalLinkage = isInAnonymousNamespace();
1662	return InternalLinkage ? M->Kind == Module::ModuleHeaderUnit ? M : M->Parent
1663	: nullptr;
1664	}
1665
1666	case Module::PrivateModuleFragment:
1667	// The private module fragment is part of its containing module for linkage
1668	// purposes.
1669	return M->Parent;
1670	}
1671
1672	llvm_unreachable("unknown module kind");
1673	}
1674
1675	void NamedDecl::printName(raw_ostream &OS, const PrintingPolicy &Policy) const {
1676	Name.print(OS, Policy);
1677	}
1678
1679	void NamedDecl::printName(raw_ostream &OS) const {
1680	printName(OS, getASTContext().getPrintingPolicy());
1681	}
1682
1683	std::string NamedDecl::getQualifiedNameAsString() const {
1684	std::string QualName;
1685	llvm::raw_string_ostream OS(QualName);
1686	printQualifiedName(OS, getASTContext().getPrintingPolicy());
1687	return QualName;
1688	}
1689
1690	void NamedDecl::printQualifiedName(raw_ostream &OS) const {
1691	printQualifiedName(OS, getASTContext().getPrintingPolicy());
1692	}
1693
1694	void NamedDecl::printQualifiedName(raw_ostream &OS,
1695	const PrintingPolicy &P) const {
1696	if (getDeclContext()->isFunctionOrMethod()) {
1697	// We do not print '(anonymous)' for function parameters without name.
1698	printName(OS, Policy: P);
1699	return;
1700	}
1701	printNestedNameSpecifier(OS, Policy: P);
1702	if (getDeclName())
1703	OS << *this;
1704	else {
1705	// Give the printName override a chance to pick a different name before we
1706	// fall back to "(anonymous)".
1707	SmallString<64> NameBuffer;
1708	llvm::raw_svector_ostream NameOS(NameBuffer);
1709	printName(OS&: NameOS, Policy: P);
1710	if (NameBuffer.empty())
1711	OS << "(anonymous)";
1712	else
1713	OS << NameBuffer;
1714	}
1715	}
1716
1717	void NamedDecl::printNestedNameSpecifier(raw_ostream &OS) const {
1718	printNestedNameSpecifier(OS, getASTContext().getPrintingPolicy());
1719	}
1720
1721	void NamedDecl::printNestedNameSpecifier(raw_ostream &OS,
1722	const PrintingPolicy &P) const {
1723	const DeclContext *Ctx = getDeclContext();
1724
1725	// For ObjC methods and properties, look through categories and use the
1726	// interface as context.
1727	if (auto *MD = dyn_cast<ObjCMethodDecl>(Val: this)) {
1728	if (auto *ID = MD->getClassInterface())
1729	Ctx = ID;
1730	} else if (auto *PD = dyn_cast<ObjCPropertyDecl>(Val: this)) {
1731	if (auto *MD = PD->getGetterMethodDecl())
1732	if (auto *ID = MD->getClassInterface())
1733	Ctx = ID;
1734	} else if (auto *ID = dyn_cast<ObjCIvarDecl>(Val: this)) {
1735	if (auto *CI = ID->getContainingInterface())
1736	Ctx = CI;
1737	}
1738
1739	if (Ctx->isFunctionOrMethod())
1740	return;
1741
1742	using ContextsTy = SmallVector<const DeclContext *, 8>;
1743	ContextsTy Contexts;
1744
1745	// Collect named contexts.
1746	DeclarationName NameInScope = getDeclName();
1747	for (; Ctx; Ctx = Ctx->getParent()) {
1748	// Suppress anonymous namespace if requested.
1749	if (P.SuppressUnwrittenScope && isa<NamespaceDecl>(Val: Ctx) &&
1750	cast<NamespaceDecl>(Val: Ctx)->isAnonymousNamespace())
1751	continue;
1752
1753	// Suppress inline namespace if it doesn't make the result ambiguous.
1754	if (P.SuppressInlineNamespace && Ctx->isInlineNamespace() && NameInScope &&
1755	cast<NamespaceDecl>(Val: Ctx)->isRedundantInlineQualifierFor(Name: NameInScope))
1756	continue;
1757
1758	// Skip non-named contexts such as linkage specifications and ExportDecls.
1759	const NamedDecl *ND = dyn_cast<NamedDecl>(Val: Ctx);
1760	if (!ND)
1761	continue;
1762
1763	Contexts.push_back(Elt: Ctx);
1764	NameInScope = ND->getDeclName();
1765	}
1766
1767	for (const DeclContext *DC : llvm::reverse(C&: Contexts)) {
1768	if (const auto *Spec = dyn_cast<ClassTemplateSpecializationDecl>(Val: DC)) {
1769	OS << Spec->getName();
1770	const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
1771	printTemplateArgumentList(
1772	OS, TemplateArgs.asArray(), P,
1773	Spec->getSpecializedTemplate()->getTemplateParameters());
1774	} else if (const auto *ND = dyn_cast<NamespaceDecl>(Val: DC)) {
1775	if (ND->isAnonymousNamespace()) {
1776	OS << (P.MSVCFormatting ? "`anonymous namespace\'"
1777	: "(anonymous namespace)");
1778	}
1779	else
1780	OS << *ND;
1781	} else if (const auto *RD = dyn_cast<RecordDecl>(Val: DC)) {
1782	if (!RD->getIdentifier())
1783	OS << "(anonymous " << RD->getKindName() << ')';
1784	else
1785	OS << *RD;
1786	} else if (const auto *FD = dyn_cast<FunctionDecl>(Val: DC)) {
1787	const FunctionProtoType *FT = nullptr;
1788	if (FD->hasWrittenPrototype())
1789	FT = dyn_cast<FunctionProtoType>(FD->getType()->castAs<FunctionType>());
1790
1791	OS << *FD << '(';
1792	if (FT) {
1793	unsigned NumParams = FD->getNumParams();
1794	for (unsigned i = 0; i < NumParams; ++i) {
1795	if (i)
1796	OS << ", ";
1797	OS << FD->getParamDecl(i)->getType().stream(P);
1798	}
1799
1800	if (FT->isVariadic()) {
1801	if (NumParams > 0)
1802	OS << ", ";
1803	OS << "...";
1804	}
1805	}
1806	OS << ')';
1807	} else if (const auto *ED = dyn_cast<EnumDecl>(Val: DC)) {
1808	// C++ [dcl.enum]p10: Each enum-name and each unscoped
1809	// enumerator is declared in the scope that immediately contains
1810	// the enum-specifier. Each scoped enumerator is declared in the
1811	// scope of the enumeration.
1812	// For the case of unscoped enumerator, do not include in the qualified
1813	// name any information about its enum enclosing scope, as its visibility
1814	// is global.
1815	if (ED->isScoped())
1816	OS << *ED;
1817	else
1818	continue;
1819	} else {
1820	OS << *cast<NamedDecl>(Val: DC);
1821	}
1822	OS << "::";
1823	}
1824	}
1825
1826	void NamedDecl::getNameForDiagnostic(raw_ostream &OS,
1827	const PrintingPolicy &Policy,
1828	bool Qualified) const {
1829	if (Qualified)
1830	printQualifiedName(OS, P: Policy);
1831	else
1832	printName(OS, Policy);
1833	}
1834
1835	template<typename T> static bool isRedeclarableImpl(Redeclarable<T> *) {
1836	return true;
1837	}
1838	static bool isRedeclarableImpl(...) { return false; }
1839	static bool isRedeclarable(Decl::Kind K) {
1840	switch (K) {
1841	#define DECL(Type, Base) \
1842	case Decl::Type: \
1843	return isRedeclarableImpl((Type##Decl *)nullptr);
1844	#define ABSTRACT_DECL(DECL)
1845	#include "clang/AST/DeclNodes.inc"
1846	}
1847	llvm_unreachable("unknown decl kind");
1848	}
1849
1850	bool NamedDecl::declarationReplaces(const NamedDecl *OldD,
1851	bool IsKnownNewer) const {
1852	assert(getDeclName() == OldD->getDeclName() && "Declaration name mismatch");
1853
1854	// Never replace one imported declaration with another; we need both results
1855	// when re-exporting.
1856	if (OldD->isFromASTFile() && isFromASTFile())
1857	return false;
1858
1859	// A kind mismatch implies that the declaration is not replaced.
1860	if (OldD->getKind() != getKind())
1861	return false;
1862
1863	// For method declarations, we never replace. (Why?)
1864	if (isa<ObjCMethodDecl>(this))
1865	return false;
1866
1867	// For parameters, pick the newer one. This is either an error or (in
1868	// Objective-C) permitted as an extension.
1869	if (isa<ParmVarDecl>(this))
1870	return true;
1871
1872	// Inline namespaces can give us two declarations with the same
1873	// name and kind in the same scope but different contexts; we should
1874	// keep both declarations in this case.
1875	if (!this->getDeclContext()->getRedeclContext()->Equals(
1876	OldD->getDeclContext()->getRedeclContext()))
1877	return false;
1878
1879	// Using declarations can be replaced if they import the same name from the
1880	// same context.
1881	if (const auto *UD = dyn_cast<UsingDecl>(this)) {
1882	ASTContext &Context = getASTContext();
1883	return Context.getCanonicalNestedNameSpecifier(NNS: UD->getQualifier()) ==
1884	Context.getCanonicalNestedNameSpecifier(
1885	NNS: cast<UsingDecl>(OldD)->getQualifier());
1886	}
1887	if (const auto *UUVD = dyn_cast<UnresolvedUsingValueDecl>(this)) {
1888	ASTContext &Context = getASTContext();
1889	return Context.getCanonicalNestedNameSpecifier(NNS: UUVD->getQualifier()) ==
1890	Context.getCanonicalNestedNameSpecifier(
1891	NNS: cast<UnresolvedUsingValueDecl>(OldD)->getQualifier());
1892	}
1893
1894	if (isRedeclarable(getKind())) {
1895	if (getCanonicalDecl() != OldD->getCanonicalDecl())
1896	return false;
1897
1898	if (IsKnownNewer)
1899	return true;
1900
1901	// Check whether this is actually newer than OldD. We want to keep the
1902	// newer declaration. This loop will usually only iterate once, because
1903	// OldD is usually the previous declaration.
1904	for (const auto *D : redecls()) {
1905	if (D == OldD)
1906	break;
1907
1908	// If we reach the canonical declaration, then OldD is not actually older
1909	// than this one.
1910	//
1911	// FIXME: In this case, we should not add this decl to the lookup table.
1912	if (D->isCanonicalDecl())
1913	return false;
1914	}
1915
1916	// It's a newer declaration of the same kind of declaration in the same
1917	// scope: we want this decl instead of the existing one.
1918	return true;
1919	}
1920
1921	// In all other cases, we need to keep both declarations in case they have
1922	// different visibility. Any attempt to use the name will result in an
1923	// ambiguity if more than one is visible.
1924	return false;
1925	}
1926
1927	bool NamedDecl::hasLinkage() const {
1928	switch (getFormalLinkage()) {
1929	case Linkage::Invalid:
1930	llvm_unreachable("Linkage hasn't been computed!");
1931	case Linkage::None:
1932	return false;
1933	case Linkage::Internal:
1934	return true;
1935	case Linkage::UniqueExternal:
1936	case Linkage::VisibleNone:
1937	llvm_unreachable("Non-formal linkage is not allowed here!");
1938	case Linkage::Module:
1939	case Linkage::External:
1940	return true;
1941	}
1942	llvm_unreachable("Unhandled Linkage enum");
1943	}
1944
1945	NamedDecl *NamedDecl::getUnderlyingDeclImpl() {
1946	NamedDecl *ND = this;
1947	if (auto *UD = dyn_cast<UsingShadowDecl>(Val: ND))
1948	ND = UD->getTargetDecl();
1949
1950	if (auto *AD = dyn_cast<ObjCCompatibleAliasDecl>(Val: ND))
1951	return AD->getClassInterface();
1952
1953	if (auto *AD = dyn_cast<NamespaceAliasDecl>(Val: ND))
1954	return AD->getNamespace();
1955
1956	return ND;
1957	}
1958
1959	bool NamedDecl::isCXXInstanceMember() const {
1960	if (!isCXXClassMember())
1961	return false;
1962
1963	const NamedDecl *D = this;
1964	if (isa<UsingShadowDecl>(Val: D))
1965	D = cast<UsingShadowDecl>(Val: D)->getTargetDecl();
1966
1967	if (isa<FieldDecl>(Val: D) || isa<IndirectFieldDecl>(Val: D) || isa<MSPropertyDecl>(Val: D))
1968	return true;
1969	if (const auto *MD = dyn_cast_if_present<CXXMethodDecl>(D->getAsFunction()))
1970	return MD->isInstance();
1971	return false;
1972	}
1973
1974	//===----------------------------------------------------------------------===//
1975	// DeclaratorDecl Implementation
1976	//===----------------------------------------------------------------------===//
1977
1978	template <typename DeclT>
1979	static SourceLocation getTemplateOrInnerLocStart(const DeclT *decl) {
1980	if (decl->getNumTemplateParameterLists() > 0)
1981	return decl->getTemplateParameterList(0)->getTemplateLoc();
1982	return decl->getInnerLocStart();
1983	}
1984
1985	SourceLocation DeclaratorDecl::getTypeSpecStartLoc() const {
1986	TypeSourceInfo *TSI = getTypeSourceInfo();
1987	if (TSI) return TSI->getTypeLoc().getBeginLoc();
1988	return SourceLocation();
1989	}
1990
1991	SourceLocation DeclaratorDecl::getTypeSpecEndLoc() const {
1992	TypeSourceInfo *TSI = getTypeSourceInfo();
1993	if (TSI) return TSI->getTypeLoc().getEndLoc();
1994	return SourceLocation();
1995	}
1996
1997	void DeclaratorDecl::setQualifierInfo(NestedNameSpecifierLoc QualifierLoc) {
1998	if (QualifierLoc) {
1999	// Make sure the extended decl info is allocated.
2000	if (!hasExtInfo()) {
2001	// Save (non-extended) type source info pointer.
2002	auto *savedTInfo = DeclInfo.get<TypeSourceInfo*>();
2003	// Allocate external info struct.
2004	DeclInfo = new (getASTContext()) ExtInfo;
2005	// Restore savedTInfo into (extended) decl info.
2006	getExtInfo()->TInfo = savedTInfo;
2007	}
2008	// Set qualifier info.
2009	getExtInfo()->QualifierLoc = QualifierLoc;
2010	} else if (hasExtInfo()) {
2011	// Here Qualifier == 0, i.e., we are removing the qualifier (if any).
2012	getExtInfo()->QualifierLoc = QualifierLoc;
2013	}
2014	}
2015
2016	void DeclaratorDecl::setTrailingRequiresClause(Expr *TrailingRequiresClause) {
2017	assert(TrailingRequiresClause);
2018	// Make sure the extended decl info is allocated.
2019	if (!hasExtInfo()) {
2020	// Save (non-extended) type source info pointer.
2021	auto *savedTInfo = DeclInfo.get<TypeSourceInfo*>();
2022	// Allocate external info struct.
2023	DeclInfo = new (getASTContext()) ExtInfo;
2024	// Restore savedTInfo into (extended) decl info.
2025	getExtInfo()->TInfo = savedTInfo;
2026	}
2027	// Set requires clause info.
2028	getExtInfo()->TrailingRequiresClause = TrailingRequiresClause;
2029	}
2030
2031	void DeclaratorDecl::setTemplateParameterListsInfo(
2032	ASTContext &Context, ArrayRef<TemplateParameterList *> TPLists) {
2033	assert(!TPLists.empty());
2034	// Make sure the extended decl info is allocated.
2035	if (!hasExtInfo()) {
2036	// Save (non-extended) type source info pointer.
2037	auto *savedTInfo = DeclInfo.get<TypeSourceInfo*>();
2038	// Allocate external info struct.
2039	DeclInfo = new (getASTContext()) ExtInfo;
2040	// Restore savedTInfo into (extended) decl info.
2041	getExtInfo()->TInfo = savedTInfo;
2042	}
2043	// Set the template parameter lists info.
2044	getExtInfo()->setTemplateParameterListsInfo(Context, TPLists);
2045	}
2046
2047	SourceLocation DeclaratorDecl::getOuterLocStart() const {
2048	return getTemplateOrInnerLocStart(decl: this);
2049	}
2050
2051	// Helper function: returns true if QT is or contains a type
2052	// having a postfix component.
2053	static bool typeIsPostfix(QualType QT) {
2054	while (true) {
2055	const Type* T = QT.getTypePtr();
2056	switch (T->getTypeClass()) {
2057	default:
2058	return false;
2059	case Type::Pointer:
2060	QT = cast<PointerType>(Val: T)->getPointeeType();
2061	break;
2062	case Type::BlockPointer:
2063	QT = cast<BlockPointerType>(Val: T)->getPointeeType();
2064	break;
2065	case Type::MemberPointer:
2066	QT = cast<MemberPointerType>(Val: T)->getPointeeType();
2067	break;
2068	case Type::LValueReference:
2069	case Type::RValueReference:
2070	QT = cast<ReferenceType>(Val: T)->getPointeeType();
2071	break;
2072	case Type::PackExpansion:
2073	QT = cast<PackExpansionType>(Val: T)->getPattern();
2074	break;
2075	case Type::Paren:
2076	case Type::ConstantArray:
2077	case Type::DependentSizedArray:
2078	case Type::IncompleteArray:
2079	case Type::VariableArray:
2080	case Type::FunctionProto:
2081	case Type::FunctionNoProto:
2082	return true;
2083	}
2084	}
2085	}
2086
2087	SourceRange DeclaratorDecl::getSourceRange() const {
2088	SourceLocation RangeEnd = getLocation();
2089	if (TypeSourceInfo *TInfo = getTypeSourceInfo()) {
2090	// If the declaration has no name or the type extends past the name take the
2091	// end location of the type.
2092	if (!getDeclName() || typeIsPostfix(QT: TInfo->getType()))
2093	RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
2094	}
2095	return SourceRange(getOuterLocStart(), RangeEnd);
2096	}
2097
2098	void QualifierInfo::setTemplateParameterListsInfo(
2099	ASTContext &Context, ArrayRef<TemplateParameterList *> TPLists) {
2100	// Free previous template parameters (if any).
2101	if (NumTemplParamLists > 0) {
2102	Context.Deallocate(Ptr: TemplParamLists);
2103	TemplParamLists = nullptr;
2104	NumTemplParamLists = 0;
2105	}
2106	// Set info on matched template parameter lists (if any).
2107	if (!TPLists.empty()) {
2108	TemplParamLists = new (Context) TemplateParameterList *[TPLists.size()];
2109	NumTemplParamLists = TPLists.size();
2110	std::copy(first: TPLists.begin(), last: TPLists.end(), result: TemplParamLists);
2111	}
2112	}
2113
2114	//===----------------------------------------------------------------------===//
2115	// VarDecl Implementation
2116	//===----------------------------------------------------------------------===//
2117
2118	const char *VarDecl::getStorageClassSpecifierString(StorageClass SC) {
2119	switch (SC) {
2120	case SC_None: break;
2121	case SC_Auto: return "auto";
2122	case SC_Extern: return "extern";
2123	case SC_PrivateExtern: return "__private_extern__";
2124	case SC_Register: return "register";
2125	case SC_Static: return "static";
2126	}
2127
2128	llvm_unreachable("Invalid storage class");
2129	}
2130
2131	VarDecl::VarDecl(Kind DK, ASTContext &C, DeclContext *DC,
2132	SourceLocation StartLoc, SourceLocation IdLoc,
2133	const IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo,
2134	StorageClass SC)
2135	: DeclaratorDecl(DK, DC, IdLoc, Id, T, TInfo, StartLoc),
2136	redeclarable_base(C) {
2137	static_assert(sizeof(VarDeclBitfields) <= sizeof(unsigned),
2138	"VarDeclBitfields too large!");
2139	static_assert(sizeof(ParmVarDeclBitfields) <= sizeof(unsigned),
2140	"ParmVarDeclBitfields too large!");
2141	static_assert(sizeof(NonParmVarDeclBitfields) <= sizeof(unsigned),
2142	"NonParmVarDeclBitfields too large!");
2143	AllBits = 0;
2144	VarDeclBits.SClass = SC;
2145	// Everything else is implicitly initialized to false.
2146	}
2147
2148	VarDecl *VarDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation StartL,
2149	SourceLocation IdL, const IdentifierInfo *Id,
2150	QualType T, TypeSourceInfo *TInfo, StorageClass S) {
2151	return new (C, DC) VarDecl(Var, C, DC, StartL, IdL, Id, T, TInfo, S);
2152	}
2153
2154	VarDecl *VarDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
2155	return new (C, ID)
2156	VarDecl(Var, C, nullptr, SourceLocation(), SourceLocation(), nullptr,
2157	QualType(), nullptr, SC_None);
2158	}
2159
2160	void VarDecl::setStorageClass(StorageClass SC) {
2161	assert(isLegalForVariable(SC));
2162	VarDeclBits.SClass = SC;
2163	}
2164
2165	VarDecl::TLSKind VarDecl::getTLSKind() const {
2166	switch (VarDeclBits.TSCSpec) {
2167	case TSCS_unspecified:
2168	if (!hasAttr<ThreadAttr>() &&
2169	!(getASTContext().getLangOpts().OpenMPUseTLS &&
2170	getASTContext().getTargetInfo().isTLSSupported() &&
2171	hasAttr<OMPThreadPrivateDeclAttr>()))
2172	return TLS_None;
2173	return ((getASTContext().getLangOpts().isCompatibleWithMSVC(
2174	LangOptions::MSVC2015)) ||
2175	hasAttr<OMPThreadPrivateDeclAttr>())
2176	? TLS_Dynamic
2177	: TLS_Static;
2178	case TSCS___thread: // Fall through.
2179	case TSCS__Thread_local:
2180	return TLS_Static;
2181	case TSCS_thread_local:
2182	return TLS_Dynamic;
2183	}
2184	llvm_unreachable("Unknown thread storage class specifier!");
2185	}
2186
2187	SourceRange VarDecl::getSourceRange() const {
2188	if (const Expr *Init = getInit()) {
2189	SourceLocation InitEnd = Init->getEndLoc();
2190	// If Init is implicit, ignore its source range and fallback on
2191	// DeclaratorDecl::getSourceRange() to handle postfix elements.
2192	if (InitEnd.isValid() && InitEnd != getLocation())
2193	return SourceRange(getOuterLocStart(), InitEnd);
2194	}
2195	return DeclaratorDecl::getSourceRange();
2196	}
2197
2198	template<typename T>
2199	static LanguageLinkage getDeclLanguageLinkage(const T &D) {
2200	// C++ [dcl.link]p1: All function types, function names with external linkage,
2201	// and variable names with external linkage have a language linkage.
2202	if (!D.hasExternalFormalLinkage())
2203	return NoLanguageLinkage;
2204
2205	// Language linkage is a C++ concept, but saying that everything else in C has
2206	// C language linkage fits the implementation nicely.
2207	if (!D.getASTContext().getLangOpts().CPlusPlus)
2208	return CLanguageLinkage;
2209
2210	// C++ [dcl.link]p4: A C language linkage is ignored in determining the
2211	// language linkage of the names of class members and the function type of
2212	// class member functions.
2213	const DeclContext *DC = D.getDeclContext();
2214	if (DC->isRecord())
2215	return CXXLanguageLinkage;
2216
2217	// If the first decl is in an extern "C" context, any other redeclaration
2218	// will have C language linkage. If the first one is not in an extern "C"
2219	// context, we would have reported an error for any other decl being in one.
2220	if (isFirstInExternCContext(&D))
2221	return CLanguageLinkage;
2222	return CXXLanguageLinkage;
2223	}
2224
2225	template<typename T>
2226	static bool isDeclExternC(const T &D) {
2227	// Since the context is ignored for class members, they can only have C++
2228	// language linkage or no language linkage.
2229	const DeclContext *DC = D.getDeclContext();
2230	if (DC->isRecord()) {
2231	assert(D.getASTContext().getLangOpts().CPlusPlus);
2232	return false;
2233	}
2234
2235	return D.getLanguageLinkage() == CLanguageLinkage;
2236	}
2237
2238	LanguageLinkage VarDecl::getLanguageLinkage() const {
2239	return getDeclLanguageLinkage(D: *this);
2240	}
2241
2242	bool VarDecl::isExternC() const {
2243	return isDeclExternC(D: *this);
2244	}
2245
2246	bool VarDecl::isInExternCContext() const {
2247	return getLexicalDeclContext()->isExternCContext();
2248	}
2249
2250	bool VarDecl::isInExternCXXContext() const {
2251	return getLexicalDeclContext()->isExternCXXContext();
2252	}
2253
2254	VarDecl *VarDecl::getCanonicalDecl() { return getFirstDecl(); }
2255
2256	VarDecl::DefinitionKind
2257	VarDecl::isThisDeclarationADefinition(ASTContext &C) const {
2258	if (isThisDeclarationADemotedDefinition())
2259	return DeclarationOnly;
2260
2261	// C++ [basic.def]p2:
2262	// A declaration is a definition unless [...] it contains the 'extern'
2263	// specifier or a linkage-specification and neither an initializer [...],
2264	// it declares a non-inline static data member in a class declaration [...],
2265	// it declares a static data member outside a class definition and the variable
2266	// was defined within the class with the constexpr specifier [...],
2267	// C++1y [temp.expl.spec]p15:
2268	// An explicit specialization of a static data member or an explicit
2269	// specialization of a static data member template is a definition if the
2270	// declaration includes an initializer; otherwise, it is a declaration.
2271	//
2272	// FIXME: How do you declare (but not define) a partial specialization of
2273	// a static data member template outside the containing class?
2274	if (isStaticDataMember()) {
2275	if (isOutOfLine() &&
2276	!(getCanonicalDecl()->isInline() &&
2277	getCanonicalDecl()->isConstexpr()) &&
2278	(hasInit() ||
2279	// If the first declaration is out-of-line, this may be an
2280	// instantiation of an out-of-line partial specialization of a variable
2281	// template for which we have not yet instantiated the initializer.
2282	(getFirstDecl()->isOutOfLine()
2283	? getTemplateSpecializationKind() == TSK_Undeclared
2284	: getTemplateSpecializationKind() !=
2285	TSK_ExplicitSpecialization) ||
2286	isa<VarTemplatePartialSpecializationDecl>(Val: this)))
2287	return Definition;
2288	if (!isOutOfLine() && isInline())
2289	return Definition;
2290	return DeclarationOnly;
2291	}
2292	// C99 6.7p5:
2293	// A definition of an identifier is a declaration for that identifier that
2294	// [...] causes storage to be reserved for that object.
2295	// Note: that applies for all non-file-scope objects.
2296	// C99 6.9.2p1:
2297	// If the declaration of an identifier for an object has file scope and an
2298	// initializer, the declaration is an external definition for the identifier
2299	if (hasInit())
2300	return Definition;
2301
2302	if (hasDefiningAttr())
2303	return Definition;
2304
2305	if (const auto *SAA = getAttr<SelectAnyAttr>())
2306	if (!SAA->isInherited())
2307	return Definition;
2308
2309	// A variable template specialization (other than a static data member
2310	// template or an explicit specialization) is a declaration until we
2311	// instantiate its initializer.
2312	if (auto *VTSD = dyn_cast<VarTemplateSpecializationDecl>(Val: this)) {
2313	if (VTSD->getTemplateSpecializationKind() != TSK_ExplicitSpecialization &&
2314	!isa<VarTemplatePartialSpecializationDecl>(Val: VTSD) &&
2315	!VTSD->IsCompleteDefinition)
2316	return DeclarationOnly;
2317	}
2318
2319	if (hasExternalStorage())
2320	return DeclarationOnly;
2321
2322	// [dcl.link] p7:
2323	// A declaration directly contained in a linkage-specification is treated
2324	// as if it contains the extern specifier for the purpose of determining
2325	// the linkage of the declared name and whether it is a definition.
2326	if (isSingleLineLanguageLinkage(*this))
2327	return DeclarationOnly;
2328
2329	// C99 6.9.2p2:
2330	// A declaration of an object that has file scope without an initializer,
2331	// and without a storage class specifier or the scs 'static', constitutes
2332	// a tentative definition.
2333	// No such thing in C++.
2334	if (!C.getLangOpts().CPlusPlus && isFileVarDecl())
2335	return TentativeDefinition;
2336
2337	// What's left is (in C, block-scope) declarations without initializers or
2338	// external storage. These are definitions.
2339	return Definition;
2340	}
2341
2342	VarDecl *VarDecl::getActingDefinition() {
2343	DefinitionKind Kind = isThisDeclarationADefinition();
2344	if (Kind != TentativeDefinition)
2345	return nullptr;
2346
2347	VarDecl *LastTentative = nullptr;
2348
2349	// Loop through the declaration chain, starting with the most recent.
2350	for (VarDecl *Decl = getMostRecentDecl(); Decl;
2351	Decl = Decl->getPreviousDecl()) {
2352	Kind = Decl->isThisDeclarationADefinition();
2353	if (Kind == Definition)
2354	return nullptr;
2355	// Record the first (most recent) TentativeDefinition that is encountered.
2356	if (Kind == TentativeDefinition && !LastTentative)
2357	LastTentative = Decl;
2358	}
2359
2360	return LastTentative;
2361	}
2362
2363	VarDecl *VarDecl::getDefinition(ASTContext &C) {
2364	VarDecl *First = getFirstDecl();
2365	for (auto *I : First->redecls()) {
2366	if (I->isThisDeclarationADefinition(C) == Definition)
2367	return I;
2368	}
2369	return nullptr;
2370	}
2371
2372	VarDecl::DefinitionKind VarDecl::hasDefinition(ASTContext &C) const {
2373	DefinitionKind Kind = DeclarationOnly;
2374
2375	const VarDecl *First = getFirstDecl();
2376	for (auto *I : First->redecls()) {
2377	Kind = std::max(Kind, I->isThisDeclarationADefinition(C));
2378	if (Kind == Definition)
2379	break;
2380	}
2381
2382	return Kind;
2383	}
2384
2385	const Expr *VarDecl::getAnyInitializer(const VarDecl *&D) const {
2386	for (auto *I : redecls()) {
2387	if (auto Expr = I->getInit()) {
2388	D = I;
2389	return Expr;
2390	}
2391	}
2392	return nullptr;
2393	}
2394
2395	bool VarDecl::hasInit() const {
2396	if (auto *P = dyn_cast<ParmVarDecl>(Val: this))
2397	if (P->hasUnparsedDefaultArg() || P->hasUninstantiatedDefaultArg())
2398	return false;
2399
2400	return !Init.isNull();
2401	}
2402
2403	Expr *VarDecl::getInit() {
2404	if (!hasInit())
2405	return nullptr;
2406
2407	if (auto *S = Init.dyn_cast<Stmt *>())
2408	return cast<Expr>(Val: S);
2409
2410	auto *Eval = getEvaluatedStmt();
2411	return cast<Expr>(Eval->Value.isOffset()
2412	? Eval->Value.get(Source: getASTContext().getExternalSource())
2413	: Eval->Value.get(Source: nullptr));
2414	}
2415
2416	Stmt **VarDecl::getInitAddress() {
2417	if (auto *ES = Init.dyn_cast<EvaluatedStmt *>())
2418	return ES->Value.getAddressOfPointer(Source: getASTContext().getExternalSource());
2419
2420	return Init.getAddrOfPtr1();
2421	}
2422
2423	VarDecl *VarDecl::getInitializingDeclaration() {
2424	VarDecl *Def = nullptr;
2425	for (auto *I : redecls()) {
2426	if (I->hasInit())
2427	return I;
2428
2429	if (I->isThisDeclarationADefinition()) {
2430	if (isStaticDataMember())
2431	return I;
2432	Def = I;
2433	}
2434	}
2435	return Def;
2436	}
2437
2438	bool VarDecl::isOutOfLine() const {
2439	if (Decl::isOutOfLine())
2440	return true;
2441
2442	if (!isStaticDataMember())
2443	return false;
2444
2445	// If this static data member was instantiated from a static data member of
2446	// a class template, check whether that static data member was defined
2447	// out-of-line.
2448	if (VarDecl *VD = getInstantiatedFromStaticDataMember())
2449	return VD->isOutOfLine();
2450
2451	return false;
2452	}
2453
2454	void VarDecl::setInit(Expr *I) {
2455	if (auto *Eval = Init.dyn_cast<EvaluatedStmt *>()) {
2456	Eval->~EvaluatedStmt();
2457	getASTContext().Deallocate(Eval);
2458	}
2459
2460	Init = I;
2461	}
2462
2463	bool VarDecl::mightBeUsableInConstantExpressions(const ASTContext &C) const {
2464	const LangOptions &Lang = C.getLangOpts();
2465
2466	// OpenCL permits const integral variables to be used in constant
2467	// expressions, like in C++98.
2468	if (!Lang.CPlusPlus && !Lang.OpenCL && !Lang.C23)
2469	return false;
2470
2471	// Function parameters are never usable in constant expressions.
2472	if (isa<ParmVarDecl>(Val: this))
2473	return false;
2474
2475	// The values of weak variables are never usable in constant expressions.
2476	if (isWeak())
2477	return false;
2478
2479	// In C++11, any variable of reference type can be used in a constant
2480	// expression if it is initialized by a constant expression.
2481	if (Lang.CPlusPlus11 && getType()->isReferenceType())
2482	return true;
2483
2484	// Only const objects can be used in constant expressions in C++. C++98 does
2485	// not require the variable to be non-volatile, but we consider this to be a
2486	// defect.
2487	if (!getType().isConstant(C) || getType().isVolatileQualified())
2488	return false;
2489
2490	// In C++, but not in C, const, non-volatile variables of integral or
2491	// enumeration types can be used in constant expressions.
2492	if (getType()->isIntegralOrEnumerationType() && !Lang.C23)
2493	return true;
2494
2495	// C23 6.6p7: An identifier that is:
2496	// ...
2497	// - declared with storage-class specifier constexpr and has an object type,
2498	// is a named constant, ... such a named constant is a constant expression
2499	// with the type and value of the declared object.
2500	// Additionally, in C++11, non-volatile constexpr variables can be used in
2501	// constant expressions.
2502	return (Lang.CPlusPlus11 || Lang.C23) && isConstexpr();
2503	}
2504
2505	bool VarDecl::isUsableInConstantExpressions(const ASTContext &Context) const {
2506	// C++2a [expr.const]p3:
2507	// A variable is usable in constant expressions after its initializing
2508	// declaration is encountered...
2509	const VarDecl *DefVD = nullptr;
2510	const Expr *Init = getAnyInitializer(D&: DefVD);
2511	if (!Init || Init->isValueDependent() || getType()->isDependentType())
2512	return false;
2513	// ... if it is a constexpr variable, or it is of reference type or of
2514	// const-qualified integral or enumeration type, ...
2515	if (!DefVD->mightBeUsableInConstantExpressions(C: Context))
2516	return false;
2517	// ... and its initializer is a constant initializer.
2518	if (Context.getLangOpts().CPlusPlus && !DefVD->hasConstantInitialization())
2519	return false;
2520	// C++98 [expr.const]p1:
2521	// An integral constant-expression can involve only [...] const variables
2522	// or static data members of integral or enumeration types initialized with
2523	// [integer] constant expressions (dcl.init)
2524	if ((Context.getLangOpts().CPlusPlus || Context.getLangOpts().OpenCL) &&
2525	!Context.getLangOpts().CPlusPlus11 && !DefVD->hasICEInitializer(Context))
2526	return false;
2527	return true;
2528	}
2529
2530	/// Convert the initializer for this declaration to the elaborated EvaluatedStmt
2531	/// form, which contains extra information on the evaluated value of the
2532	/// initializer.
2533	EvaluatedStmt *VarDecl::ensureEvaluatedStmt() const {
2534	auto *Eval = Init.dyn_cast<EvaluatedStmt *>();
2535	if (!Eval) {
2536	// Note: EvaluatedStmt contains an APValue, which usually holds
2537	// resources not allocated from the ASTContext. We need to do some
2538	// work to avoid leaking those, but we do so in VarDecl::evaluateValue
2539	// where we can detect whether there's anything to clean up or not.
2540	Eval = new (getASTContext()) EvaluatedStmt;
2541	Eval->Value = Init.get<Stmt *>();
2542	Init = Eval;
2543	}
2544	return Eval;
2545	}
2546
2547	EvaluatedStmt *VarDecl::getEvaluatedStmt() const {
2548	return Init.dyn_cast<EvaluatedStmt *>();
2549	}
2550
2551	APValue *VarDecl::evaluateValue() const {
2552	SmallVector<PartialDiagnosticAt, 8> Notes;
2553	return evaluateValueImpl(Notes, IsConstantInitialization: hasConstantInitialization());
2554	}
2555
2556	APValue *VarDecl::evaluateValueImpl(SmallVectorImpl<PartialDiagnosticAt> &Notes,
2557	bool IsConstantInitialization) const {
2558	EvaluatedStmt *Eval = ensureEvaluatedStmt();
2559
2560	const auto *Init = getInit();
2561	assert(!Init->isValueDependent());
2562
2563	// We only produce notes indicating why an initializer is non-constant the
2564	// first time it is evaluated. FIXME: The notes won't always be emitted the
2565	// first time we try evaluation, so might not be produced at all.
2566	if (Eval->WasEvaluated)
2567	return Eval->Evaluated.isAbsent() ? nullptr : &Eval->Evaluated;
2568
2569	if (Eval->IsEvaluating) {
2570	// FIXME: Produce a diagnostic for self-initialization.
2571	return nullptr;
2572	}
2573
2574	Eval->IsEvaluating = true;
2575
2576	ASTContext &Ctx = getASTContext();
2577	bool Result = Init->EvaluateAsInitializer(Result&: Eval->Evaluated, Ctx, VD: this, Notes,
2578	IsConstantInitializer: IsConstantInitialization);
2579
2580	// In C++, or in C23 if we're initialising a 'constexpr' variable, this isn't
2581	// a constant initializer if we produced notes. In that case, we can't keep
2582	// the result, because it may only be correct under the assumption that the
2583	// initializer is a constant context.
2584	if (IsConstantInitialization &&
2585	(Ctx.getLangOpts().CPlusPlus ||
2586	(isConstexpr() && Ctx.getLangOpts().C23)) &&
2587	!Notes.empty())
2588	Result = false;
2589
2590	// Ensure the computed APValue is cleaned up later if evaluation succeeded,
2591	// or that it's empty (so that there's nothing to clean up) if evaluation
2592	// failed.
2593	if (!Result)
2594	Eval->Evaluated = APValue();
2595	else if (Eval->Evaluated.needsCleanup())
2596	Ctx.addDestruction(Ptr: &Eval->Evaluated);
2597
2598	Eval->IsEvaluating = false;
2599	Eval->WasEvaluated = true;
2600
2601	return Result ? &Eval->Evaluated : nullptr;
2602	}
2603
2604	APValue *VarDecl::getEvaluatedValue() const {
2605	if (EvaluatedStmt *Eval = getEvaluatedStmt())
2606	if (Eval->WasEvaluated)
2607	return &Eval->Evaluated;
2608
2609	return nullptr;
2610	}
2611
2612	bool VarDecl::hasICEInitializer(const ASTContext &Context) const {
2613	const Expr *Init = getInit();
2614	assert(Init && "no initializer");
2615
2616	EvaluatedStmt *Eval = ensureEvaluatedStmt();
2617	if (!Eval->CheckedForICEInit) {
2618	Eval->CheckedForICEInit = true;
2619	Eval->HasICEInit = Init->isIntegerConstantExpr(Ctx: Context);
2620	}
2621	return Eval->HasICEInit;
2622	}
2623
2624	bool VarDecl::hasConstantInitialization() const {
2625	// In C, all globals (and only globals) have constant initialization.
2626	if (hasGlobalStorage() && !getASTContext().getLangOpts().CPlusPlus)
2627	return true;
2628
2629	// In C++, it depends on whether the evaluation at the point of definition
2630	// was evaluatable as a constant initializer.
2631	if (EvaluatedStmt *Eval = getEvaluatedStmt())
2632	return Eval->HasConstantInitialization;
2633
2634	return false;
2635	}
2636
2637	bool VarDecl::checkForConstantInitialization(
2638	SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
2639	EvaluatedStmt *Eval = ensureEvaluatedStmt();
2640	// If we ask for the value before we know whether we have a constant
2641	// initializer, we can compute the wrong value (for example, due to
2642	// std::is_constant_evaluated()).
2643	assert(!Eval->WasEvaluated &&
2644	"already evaluated var value before checking for constant init");
2645	assert((getASTContext().getLangOpts().CPlusPlus ||
2646	getASTContext().getLangOpts().C23) &&
2647	"only meaningful in C++/C23");
2648
2649	assert(!getInit()->isValueDependent());
2650
2651	// Evaluate the initializer to check whether it's a constant expression.
2652	Eval->HasConstantInitialization =
2653	evaluateValueImpl(Notes, IsConstantInitialization: true) && Notes.empty();
2654
2655	// If evaluation as a constant initializer failed, allow re-evaluation as a
2656	// non-constant initializer if we later find we want the value.
2657	if (!Eval->HasConstantInitialization)
2658	Eval->WasEvaluated = false;
2659
2660	return Eval->HasConstantInitialization;
2661	}
2662
2663	bool VarDecl::isParameterPack() const {
2664	return isa<PackExpansionType>(getType());
2665	}
2666
2667	template<typename DeclT>
2668	static DeclT *getDefinitionOrSelf(DeclT *D) {
2669	assert(D);
2670	if (auto *Def = D->getDefinition())
2671	return Def;
2672	return D;
2673	}
2674
2675	bool VarDecl::isEscapingByref() const {
2676	return hasAttr<BlocksAttr>() && NonParmVarDeclBits.EscapingByref;
2677	}
2678
2679	bool VarDecl::isNonEscapingByref() const {
2680	return hasAttr<BlocksAttr>() && !NonParmVarDeclBits.EscapingByref;
2681	}
2682
2683	bool VarDecl::hasDependentAlignment() const {
2684	QualType T = getType();
2685	return T->isDependentType() || T->isUndeducedType() ||
2686	llvm::any_of(specific_attrs<AlignedAttr>(), [](const AlignedAttr *AA) {
2687	return AA->isAlignmentDependent();
2688	});
2689	}
2690
2691	VarDecl *VarDecl::getTemplateInstantiationPattern() const {
2692	const VarDecl *VD = this;
2693
2694	// If this is an instantiated member, walk back to the template from which
2695	// it was instantiated.
2696	if (MemberSpecializationInfo *MSInfo = VD->getMemberSpecializationInfo()) {
2697	if (isTemplateInstantiation(Kind: MSInfo->getTemplateSpecializationKind())) {
2698	VD = VD->getInstantiatedFromStaticDataMember();
2699	while (auto *NewVD = VD->getInstantiatedFromStaticDataMember())
2700	VD = NewVD;
2701	}
2702	}
2703
2704	// If it's an instantiated variable template specialization, find the
2705	// template or partial specialization from which it was instantiated.
2706	if (auto *VDTemplSpec = dyn_cast<VarTemplateSpecializationDecl>(Val: VD)) {
2707	if (isTemplateInstantiation(VDTemplSpec->getTemplateSpecializationKind())) {
2708	auto From = VDTemplSpec->getInstantiatedFrom();
2709	if (auto *VTD = From.dyn_cast<VarTemplateDecl *>()) {
2710	while (!VTD->isMemberSpecialization()) {
2711	auto *NewVTD = VTD->getInstantiatedFromMemberTemplate();
2712	if (!NewVTD)
2713	break;
2714	VTD = NewVTD;
2715	}
2716	return getDefinitionOrSelf(D: VTD->getTemplatedDecl());
2717	}
2718	if (auto *VTPSD =
2719	From.dyn_cast<VarTemplatePartialSpecializationDecl *>()) {
2720	while (!VTPSD->isMemberSpecialization()) {
2721	auto *NewVTPSD = VTPSD->getInstantiatedFromMember();
2722	if (!NewVTPSD)
2723	break;
2724	VTPSD = NewVTPSD;
2725	}
2726	return getDefinitionOrSelf<VarDecl>(VTPSD);
2727	}
2728	}
2729	}
2730
2731	// If this is the pattern of a variable template, find where it was
2732	// instantiated from. FIXME: Is this necessary?
2733	if (VarTemplateDecl *VarTemplate = VD->getDescribedVarTemplate()) {
2734	while (!VarTemplate->isMemberSpecialization()) {
2735	auto *NewVT = VarTemplate->getInstantiatedFromMemberTemplate();
2736	if (!NewVT)
2737	break;
2738	VarTemplate = NewVT;
2739	}
2740
2741	return getDefinitionOrSelf(D: VarTemplate->getTemplatedDecl());
2742	}
2743
2744	if (VD == this)
2745	return nullptr;
2746	return getDefinitionOrSelf(D: const_cast<VarDecl*>(VD));
2747	}
2748
2749	VarDecl *VarDecl::getInstantiatedFromStaticDataMember() const {
2750	if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
2751	return cast<VarDecl>(Val: MSI->getInstantiatedFrom());
2752
2753	return nullptr;
2754	}
2755
2756	TemplateSpecializationKind VarDecl::getTemplateSpecializationKind() const {
2757	if (const auto *Spec = dyn_cast<VarTemplateSpecializationDecl>(Val: this))
2758	return Spec->getSpecializationKind();
2759
2760	if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
2761	return MSI->getTemplateSpecializationKind();
2762
2763	return TSK_Undeclared;
2764	}
2765
2766	TemplateSpecializationKind
2767	VarDecl::getTemplateSpecializationKindForInstantiation() const {
2768	if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
2769	return MSI->getTemplateSpecializationKind();
2770
2771	if (const auto *Spec = dyn_cast<VarTemplateSpecializationDecl>(Val: this))
2772	return Spec->getSpecializationKind();
2773
2774	return TSK_Undeclared;
2775	}
2776
2777	SourceLocation VarDecl::getPointOfInstantiation() const {
2778	if (const auto *Spec = dyn_cast<VarTemplateSpecializationDecl>(Val: this))
2779	return Spec->getPointOfInstantiation();
2780
2781	if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
2782	return MSI->getPointOfInstantiation();
2783
2784	return SourceLocation();
2785	}
2786
2787	VarTemplateDecl *VarDecl::getDescribedVarTemplate() const {
2788	return getASTContext().getTemplateOrSpecializationInfo(this)
2789	.dyn_cast<VarTemplateDecl *>();
2790	}
2791
2792	void VarDecl::setDescribedVarTemplate(VarTemplateDecl *Template) {
2793	getASTContext().setTemplateOrSpecializationInfo(this, Template);
2794	}
2795
2796	bool VarDecl::isKnownToBeDefined() const {
2797	const auto &LangOpts = getASTContext().getLangOpts();
2798	// In CUDA mode without relocatable device code, variables of form 'extern
2799	// __shared__ Foo foo[]' are pointers to the base of the GPU core's shared
2800	// memory pool. These are never undefined variables, even if they appear
2801	// inside of an anon namespace or static function.
2802	//
2803	// With CUDA relocatable device code enabled, these variables don't get
2804	// special handling; they're treated like regular extern variables.
2805	if (LangOpts.CUDA && !LangOpts.GPURelocatableDeviceCode &&
2806	hasExternalStorage() && hasAttr<CUDASharedAttr>() &&
2807	isa<IncompleteArrayType>(getType()))
2808	return true;
2809
2810	return hasDefinition();
2811	}
2812
2813	bool VarDecl::isNoDestroy(const ASTContext &Ctx) const {
2814	return hasGlobalStorage() && (hasAttr<NoDestroyAttr>() ||
2815	(!Ctx.getLangOpts().RegisterStaticDestructors &&
2816	!hasAttr<AlwaysDestroyAttr>()));
2817	}
2818
2819	QualType::DestructionKind
2820	VarDecl::needsDestruction(const ASTContext &Ctx) const {
2821	if (EvaluatedStmt *Eval = getEvaluatedStmt())
2822	if (Eval->HasConstantDestruction)
2823	return QualType::DK_none;
2824
2825	if (isNoDestroy(Ctx))
2826	return QualType::DK_none;
2827
2828	return getType().isDestructedType();
2829	}
2830
2831	bool VarDecl::hasFlexibleArrayInit(const ASTContext &Ctx) const {
2832	assert(hasInit() && "Expect initializer to check for flexible array init");
2833	auto *Ty = getType()->getAs<RecordType>();
2834	if (!Ty || !Ty->getDecl()->hasFlexibleArrayMember())
2835	return false;
2836	auto *List = dyn_cast<InitListExpr>(Val: getInit()->IgnoreParens());
2837	if (!List)
2838	return false;
2839	const Expr *FlexibleInit = List->getInit(Init: List->getNumInits() - 1);
2840	auto InitTy = Ctx.getAsConstantArrayType(T: FlexibleInit->getType());
2841	if (!InitTy)
2842	return false;
2843	return !InitTy->isZeroSize();
2844	}
2845
2846	CharUnits VarDecl::getFlexibleArrayInitChars(const ASTContext &Ctx) const {
2847	assert(hasInit() && "Expect initializer to check for flexible array init");
2848	auto *Ty = getType()->getAs<RecordType>();
2849	if (!Ty || !Ty->getDecl()->hasFlexibleArrayMember())
2850	return CharUnits::Zero();
2851	auto *List = dyn_cast<InitListExpr>(Val: getInit()->IgnoreParens());
2852	if (!List || List->getNumInits() == 0)
2853	return CharUnits::Zero();
2854	const Expr *FlexibleInit = List->getInit(Init: List->getNumInits() - 1);
2855	auto InitTy = Ctx.getAsConstantArrayType(T: FlexibleInit->getType());
2856	if (!InitTy)
2857	return CharUnits::Zero();
2858	CharUnits FlexibleArraySize = Ctx.getTypeSizeInChars(InitTy);
2859	const ASTRecordLayout &RL = Ctx.getASTRecordLayout(D: Ty->getDecl());
2860	CharUnits FlexibleArrayOffset =
2861	Ctx.toCharUnitsFromBits(BitSize: RL.getFieldOffset(FieldNo: RL.getFieldCount() - 1));
2862	if (FlexibleArrayOffset + FlexibleArraySize < RL.getSize())
2863	return CharUnits::Zero();
2864	return FlexibleArrayOffset + FlexibleArraySize - RL.getSize();
2865	}
2866
2867	MemberSpecializationInfo *VarDecl::getMemberSpecializationInfo() const {
2868	if (isStaticDataMember())
2869	// FIXME: Remove ?
2870	// return getASTContext().getInstantiatedFromStaticDataMember(this);
2871	return getASTContext().getTemplateOrSpecializationInfo(this)
2872	.dyn_cast<MemberSpecializationInfo *>();
2873	return nullptr;
2874	}
2875
2876	void VarDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
2877	SourceLocation PointOfInstantiation) {
2878	assert((isa<VarTemplateSpecializationDecl>(this) ||
2879	getMemberSpecializationInfo()) &&
2880	"not a variable or static data member template specialization");
2881
2882	if (VarTemplateSpecializationDecl *Spec =
2883	dyn_cast<VarTemplateSpecializationDecl>(Val: this)) {
2884	Spec->setSpecializationKind(TSK);
2885	if (TSK != TSK_ExplicitSpecialization &&
2886	PointOfInstantiation.isValid() &&
2887	Spec->getPointOfInstantiation().isInvalid()) {
2888	Spec->setPointOfInstantiation(PointOfInstantiation);
2889	if (ASTMutationListener *L = getASTContext().getASTMutationListener())
2890	L->InstantiationRequested(this);
2891	}
2892	} else if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo()) {
2893	MSI->setTemplateSpecializationKind(TSK);
2894	if (TSK != TSK_ExplicitSpecialization && PointOfInstantiation.isValid() &&
2895	MSI->getPointOfInstantiation().isInvalid()) {
2896	MSI->setPointOfInstantiation(PointOfInstantiation);
2897	if (ASTMutationListener *L = getASTContext().getASTMutationListener())
2898	L->InstantiationRequested(this);
2899	}
2900	}
2901	}
2902
2903	void
2904	VarDecl::setInstantiationOfStaticDataMember(VarDecl *VD,
2905	TemplateSpecializationKind TSK) {
2906	assert(getASTContext().getTemplateOrSpecializationInfo(this).isNull() &&
2907	"Previous template or instantiation?");
2908	getASTContext().setInstantiatedFromStaticDataMember(this, VD, TSK);
2909	}
2910
2911	//===----------------------------------------------------------------------===//
2912	// ParmVarDecl Implementation
2913	//===----------------------------------------------------------------------===//
2914
2915	ParmVarDecl *ParmVarDecl::Create(ASTContext &C, DeclContext *DC,
2916	SourceLocation StartLoc, SourceLocation IdLoc,
2917	const IdentifierInfo *Id, QualType T,
2918	TypeSourceInfo *TInfo, StorageClass S,
2919	Expr *DefArg) {
2920	return new (C, DC) ParmVarDecl(ParmVar, C, DC, StartLoc, IdLoc, Id, T, TInfo,
2921	S, DefArg);
2922	}
2923
2924	QualType ParmVarDecl::getOriginalType() const {
2925	TypeSourceInfo *TSI = getTypeSourceInfo();
2926	QualType T = TSI ? TSI->getType() : getType();
2927	if (const auto *DT = dyn_cast<DecayedType>(T))
2928	return DT->getOriginalType();
2929	return T;
2930	}
2931
2932	ParmVarDecl *ParmVarDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
2933	return new (C, ID)
2934	ParmVarDecl(ParmVar, C, nullptr, SourceLocation(), SourceLocation(),
2935	nullptr, QualType(), nullptr, SC_None, nullptr);
2936	}
2937
2938	SourceRange ParmVarDecl::getSourceRange() const {
2939	if (!hasInheritedDefaultArg()) {
2940	SourceRange ArgRange = getDefaultArgRange();
2941	if (ArgRange.isValid())
2942	return SourceRange(getOuterLocStart(), ArgRange.getEnd());
2943	}
2944
2945	// DeclaratorDecl considers the range of postfix types as overlapping with the
2946	// declaration name, but this is not the case with parameters in ObjC methods.
2947	if (isa<ObjCMethodDecl>(getDeclContext()))
2948	return SourceRange(DeclaratorDecl::getBeginLoc(), getLocation());
2949
2950	return DeclaratorDecl::getSourceRange();
2951	}
2952
2953	bool ParmVarDecl::isDestroyedInCallee() const {
2954	// ns_consumed only affects code generation in ARC
2955	if (hasAttr<NSConsumedAttr>())
2956	return getASTContext().getLangOpts().ObjCAutoRefCount;
2957
2958	// FIXME: isParamDestroyedInCallee() should probably imply
2959	// isDestructedType()
2960	const auto *RT = getType()->getAs<RecordType>();
2961	if (RT && RT->getDecl()->isParamDestroyedInCallee() &&
2962	getType().isDestructedType())
2963	return true;
2964
2965	return false;
2966	}
2967
2968	Expr *ParmVarDecl::getDefaultArg() {
2969	assert(!hasUnparsedDefaultArg() && "Default argument is not yet parsed!");
2970	assert(!hasUninstantiatedDefaultArg() &&
2971	"Default argument is not yet instantiated!");
2972
2973	Expr *Arg = getInit();
2974	if (auto *E = dyn_cast_if_present<FullExpr>(Arg))
2975	return E->getSubExpr();
2976
2977	return Arg;
2978	}
2979
2980	void ParmVarDecl::setDefaultArg(Expr *defarg) {
2981	ParmVarDeclBits.DefaultArgKind = DAK_Normal;
2982	Init = defarg;
2983	}
2984
2985	SourceRange ParmVarDecl::getDefaultArgRange() const {
2986	switch (ParmVarDeclBits.DefaultArgKind) {
2987	case DAK_None:
2988	case DAK_Unparsed:
2989	// Nothing we can do here.
2990	return SourceRange();
2991
2992	case DAK_Uninstantiated:
2993	return getUninstantiatedDefaultArg()->getSourceRange();
2994
2995	case DAK_Normal:
2996	if (const Expr *E = getInit())
2997	return E->getSourceRange();
2998
2999	// Missing an actual expression, may be invalid.
3000	return SourceRange();
3001	}
3002	llvm_unreachable("Invalid default argument kind.");
3003	}
3004
3005	void ParmVarDecl::setUninstantiatedDefaultArg(Expr *arg) {
3006	ParmVarDeclBits.DefaultArgKind = DAK_Uninstantiated;
3007	Init = arg;
3008	}
3009
3010	Expr *ParmVarDecl::getUninstantiatedDefaultArg() {
3011	assert(hasUninstantiatedDefaultArg() &&
3012	"Wrong kind of initialization expression!");
3013	return cast_if_present<Expr>(Val: Init.get<Stmt *>());
3014	}
3015
3016	bool ParmVarDecl::hasDefaultArg() const {
3017	// FIXME: We should just return false for DAK_None here once callers are
3018	// prepared for the case that we encountered an invalid default argument and
3019	// were unable to even build an invalid expression.
3020	return hasUnparsedDefaultArg() || hasUninstantiatedDefaultArg() ||
3021	!Init.isNull();
3022	}
3023
3024	void ParmVarDecl::setParameterIndexLarge(unsigned parameterIndex) {
3025	getASTContext().setParameterIndex(this, parameterIndex);
3026	ParmVarDeclBits.ParameterIndex = ParameterIndexSentinel;
3027	}
3028
3029	unsigned ParmVarDecl::getParameterIndexLarge() const {
3030	return getASTContext().getParameterIndex(this);
3031	}
3032
3033	//===----------------------------------------------------------------------===//
3034	// FunctionDecl Implementation
3035	//===----------------------------------------------------------------------===//
3036
3037	FunctionDecl::FunctionDecl(Kind DK, ASTContext &C, DeclContext *DC,
3038	SourceLocation StartLoc,
3039	const DeclarationNameInfo &NameInfo, QualType T,
3040	TypeSourceInfo *TInfo, StorageClass S,
3041	bool UsesFPIntrin, bool isInlineSpecified,
3042	ConstexprSpecKind ConstexprKind,
3043	Expr *TrailingRequiresClause)
3044	: DeclaratorDecl(DK, DC, NameInfo.getLoc(), NameInfo.getName(), T, TInfo,
3045	StartLoc),
3046	DeclContext(DK), redeclarable_base(C), Body(), ODRHash(0),
3047	EndRangeLoc(NameInfo.getEndLoc()), DNLoc(NameInfo.getInfo()) {
3048	assert(T.isNull() || T->isFunctionType());
3049	FunctionDeclBits.SClass = S;
3050	FunctionDeclBits.IsInline = isInlineSpecified;
3051	FunctionDeclBits.IsInlineSpecified = isInlineSpecified;
3052	FunctionDeclBits.IsVirtualAsWritten = false;
3053	FunctionDeclBits.IsPureVirtual = false;
3054	FunctionDeclBits.HasInheritedPrototype = false;
3055	FunctionDeclBits.HasWrittenPrototype = true;
3056	FunctionDeclBits.IsDeleted = false;
3057	FunctionDeclBits.IsTrivial = false;
3058	FunctionDeclBits.IsTrivialForCall = false;
3059	FunctionDeclBits.IsDefaulted = false;
3060	FunctionDeclBits.IsExplicitlyDefaulted = false;
3061	FunctionDeclBits.HasDefaultedOrDeletedInfo = false;
3062	FunctionDeclBits.IsIneligibleOrNotSelected = false;
3063	FunctionDeclBits.HasImplicitReturnZero = false;
3064	FunctionDeclBits.IsLateTemplateParsed = false;
3065	FunctionDeclBits.ConstexprKind = static_cast<uint64_t>(ConstexprKind);
3066	FunctionDeclBits.BodyContainsImmediateEscalatingExpression = false;
3067	FunctionDeclBits.InstantiationIsPending = false;
3068	FunctionDeclBits.UsesSEHTry = false;
3069	FunctionDeclBits.UsesFPIntrin = UsesFPIntrin;
3070	FunctionDeclBits.HasSkippedBody = false;
3071	FunctionDeclBits.WillHaveBody = false;
3072	FunctionDeclBits.IsMultiVersion = false;
3073	FunctionDeclBits.DeductionCandidateKind =
3074	static_cast<unsigned char>(DeductionCandidate::Normal);
3075	FunctionDeclBits.HasODRHash = false;
3076	FunctionDeclBits.FriendConstraintRefersToEnclosingTemplate = false;
3077	if (TrailingRequiresClause)
3078	setTrailingRequiresClause(TrailingRequiresClause);
3079	}
3080
3081	void FunctionDecl::getNameForDiagnostic(
3082	raw_ostream &OS, const PrintingPolicy &Policy, bool Qualified) const {
3083	NamedDecl::getNameForDiagnostic(OS, Policy, Qualified);
3084	const TemplateArgumentList *TemplateArgs = getTemplateSpecializationArgs();
3085	if (TemplateArgs)
3086	printTemplateArgumentList(OS, Args: TemplateArgs->asArray(), Policy);
3087	}
3088
3089	bool FunctionDecl::isVariadic() const {
3090	if (const auto *FT = getType()->getAs<FunctionProtoType>())
3091	return FT->isVariadic();
3092	return false;
3093	}
3094
3095	FunctionDecl::DefaultedOrDeletedFunctionInfo *
3096	FunctionDecl::DefaultedOrDeletedFunctionInfo::Create(
3097	ASTContext &Context, ArrayRef<DeclAccessPair> Lookups,
3098	StringLiteral *DeletedMessage) {
3099	static constexpr size_t Alignment =
3100	std::max(l: {alignof(DefaultedOrDeletedFunctionInfo),
3101	alignof(DeclAccessPair), alignof(StringLiteral *)});
3102	size_t Size = totalSizeToAlloc<DeclAccessPair, StringLiteral *>(
3103	Counts: Lookups.size(), Counts: DeletedMessage != nullptr);
3104
3105	DefaultedOrDeletedFunctionInfo *Info =
3106	new (Context.Allocate(Size, Align: Alignment)) DefaultedOrDeletedFunctionInfo;
3107	Info->NumLookups = Lookups.size();
3108	Info->HasDeletedMessage = DeletedMessage != nullptr;
3109
3110	std::uninitialized_copy(first: Lookups.begin(), last: Lookups.end(),
3111	result: Info->getTrailingObjects<DeclAccessPair>());
3112	if (DeletedMessage)
3113	*Info->getTrailingObjects<StringLiteral *>() = DeletedMessage;
3114	return Info;
3115	}
3116
3117	void FunctionDecl::setDefaultedOrDeletedInfo(
3118	DefaultedOrDeletedFunctionInfo *Info) {
3119	assert(!FunctionDeclBits.HasDefaultedOrDeletedInfo && "already have this");
3120	assert(!Body && "can't replace function body with defaulted function info");
3121
3122	FunctionDeclBits.HasDefaultedOrDeletedInfo = true;
3123	DefaultedOrDeletedInfo = Info;
3124	}
3125
3126	void FunctionDecl::setDeletedAsWritten(bool D, StringLiteral *Message) {
3127	FunctionDeclBits.IsDeleted = D;
3128
3129	if (Message) {
3130	assert(isDeletedAsWritten() && "Function must be deleted");
3131	if (FunctionDeclBits.HasDefaultedOrDeletedInfo)
3132	DefaultedOrDeletedInfo->setDeletedMessage(Message);
3133	else
3134	setDefaultedOrDeletedInfo(DefaultedOrDeletedFunctionInfo::Create(
3135	Context&: getASTContext(), /*Lookups=*/{}, DeletedMessage: Message));
3136	}
3137	}
3138
3139	void FunctionDecl::DefaultedOrDeletedFunctionInfo::setDeletedMessage(
3140	StringLiteral *Message) {
3141	// We should never get here with the DefaultedOrDeletedInfo populated, but
3142	// no space allocated for the deleted message, since that would require
3143	// recreating this, but setDefaultedOrDeletedInfo() disallows overwriting
3144	// an already existing DefaultedOrDeletedFunctionInfo.
3145	assert(HasDeletedMessage &&
3146	"No space to store a delete message in this DefaultedOrDeletedInfo");
3147	*getTrailingObjects<StringLiteral *>() = Message;
3148	}
3149
3150	FunctionDecl::DefaultedOrDeletedFunctionInfo *
3151	FunctionDecl::getDefalutedOrDeletedInfo() const {
3152	return FunctionDeclBits.HasDefaultedOrDeletedInfo ? DefaultedOrDeletedInfo
3153	: nullptr;
3154	}
3155
3156	bool FunctionDecl::hasBody(const FunctionDecl *&Definition) const {
3157	for (const auto *I : redecls()) {
3158	if (I->doesThisDeclarationHaveABody()) {
3159	Definition = I;
3160	return true;
3161	}
3162	}
3163
3164	return false;
3165	}
3166
3167	bool FunctionDecl::hasTrivialBody() const {
3168	const Stmt *S = getBody();
3169	if (!S) {
3170	// Since we don't have a body for this function, we don't know if it's
3171	// trivial or not.
3172	return false;
3173	}
3174
3175	if (isa<CompoundStmt>(Val: S) && cast<CompoundStmt>(Val: S)->body_empty())
3176	return true;
3177	return false;
3178	}
3179
3180	bool FunctionDecl::isThisDeclarationInstantiatedFromAFriendDefinition() const {
3181	if (!getFriendObjectKind())
3182	return false;
3183
3184	// Check for a friend function instantiated from a friend function
3185	// definition in a templated class.
3186	if (const FunctionDecl *InstantiatedFrom =
3187	getInstantiatedFromMemberFunction())
3188	return InstantiatedFrom->getFriendObjectKind() &&
3189	InstantiatedFrom->isThisDeclarationADefinition();
3190
3191	// Check for a friend function template instantiated from a friend
3192	// function template definition in a templated class.
3193	if (const FunctionTemplateDecl *Template = getDescribedFunctionTemplate()) {
3194	if (const FunctionTemplateDecl *InstantiatedFrom =
3195	Template->getInstantiatedFromMemberTemplate())
3196	return InstantiatedFrom->getFriendObjectKind() &&
3197	InstantiatedFrom->isThisDeclarationADefinition();
3198	}
3199
3200	return false;
3201	}
3202
3203	bool FunctionDecl::isDefined(const FunctionDecl *&Definition,
3204	bool CheckForPendingFriendDefinition) const {
3205	for (const FunctionDecl *FD : redecls()) {
3206	if (FD->isThisDeclarationADefinition()) {
3207	Definition = FD;
3208	return true;
3209	}
3210
3211	// If this is a friend function defined in a class template, it does not
3212	// have a body until it is used, nevertheless it is a definition, see
3213	// [temp.inst]p2:
3214	//
3215	// ... for the purpose of determining whether an instantiated redeclaration
3216	// is valid according to [basic.def.odr] and [class.mem], a declaration that
3217	// corresponds to a definition in the template is considered to be a
3218	// definition.
3219	//
3220	// The following code must produce redefinition error:
3221	//
3222	// template<typename T> struct C20 { friend void func_20() {} };
3223	// C20<int> c20i;
3224	// void func_20() {}
3225	//
3226	if (CheckForPendingFriendDefinition &&
3227	FD->isThisDeclarationInstantiatedFromAFriendDefinition()) {
3228	Definition = FD;
3229	return true;
3230	}
3231	}
3232
3233	return false;
3234	}
3235
3236	Stmt *FunctionDecl::getBody(const FunctionDecl *&Definition) const {
3237	if (!hasBody(Definition))
3238	return nullptr;
3239
3240	assert(!Definition->FunctionDeclBits.HasDefaultedOrDeletedInfo &&
3241	"definition should not have a body");
3242	if (Definition->Body)
3243	return Definition->Body.get(Source: getASTContext().getExternalSource());
3244
3245	return nullptr;
3246	}
3247
3248	void FunctionDecl::setBody(Stmt *B) {
3249	FunctionDeclBits.HasDefaultedOrDeletedInfo = false;
3250	Body = LazyDeclStmtPtr(B);
3251	if (B)
3252	EndRangeLoc = B->getEndLoc();
3253	}
3254
3255	void FunctionDecl::setIsPureVirtual(bool P) {
3256	FunctionDeclBits.IsPureVirtual = P;
3257	if (P)
3258	if (auto *Parent = dyn_cast<CXXRecordDecl>(getDeclContext()))
3259	Parent->markedVirtualFunctionPure();
3260	}
3261
3262	template<std::size_t Len>
3263	static bool isNamed(const NamedDecl *ND, const char (&Str)[Len]) {
3264	const IdentifierInfo *II = ND->getIdentifier();
3265	return II && II->isStr(Str);
3266	}
3267
3268	bool FunctionDecl::isImmediateEscalating() const {
3269	// C++23 [expr.const]/p17
3270	// An immediate-escalating function is
3271	// - the call operator of a lambda that is not declared with the consteval
3272	// specifier,
3273	if (isLambdaCallOperator(this) && !isConsteval())
3274	return true;
3275	// - a defaulted special member function that is not declared with the
3276	// consteval specifier,
3277	if (isDefaulted() && !isConsteval())
3278	return true;
3279	// - a function that results from the instantiation of a templated entity
3280	// defined with the constexpr specifier.
3281	TemplatedKind TK = getTemplatedKind();
3282	if (TK != TK_NonTemplate && TK != TK_DependentNonTemplate &&
3283	isConstexprSpecified())
3284	return true;
3285	return false;
3286	}
3287
3288	bool FunctionDecl::isImmediateFunction() const {
3289	// C++23 [expr.const]/p18
3290	// An immediate function is a function or constructor that is
3291	// - declared with the consteval specifier
3292	if (isConsteval())
3293	return true;
3294	// - an immediate-escalating function F whose function body contains an
3295	// immediate-escalating expression
3296	if (isImmediateEscalating() && BodyContainsImmediateEscalatingExpressions())
3297	return true;
3298
3299	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: this);
3300	MD && MD->isLambdaStaticInvoker())
3301	return MD->getParent()->getLambdaCallOperator()->isImmediateFunction();
3302
3303	return false;
3304	}
3305
3306	bool FunctionDecl::isMain() const {
3307	const TranslationUnitDecl *tunit =
3308	dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
3309	return tunit &&
3310	!tunit->getASTContext().getLangOpts().Freestanding &&
3311	isNamed(this, "main");
3312	}
3313
3314	bool FunctionDecl::isMSVCRTEntryPoint() const {
3315	const TranslationUnitDecl *TUnit =
3316	dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
3317	if (!TUnit)
3318	return false;
3319
3320	// Even though we aren't really targeting MSVCRT if we are freestanding,
3321	// semantic analysis for these functions remains the same.
3322
3323	// MSVCRT entry points only exist on MSVCRT targets.
3324	if (!TUnit->getASTContext().getTargetInfo().getTriple().isOSMSVCRT())
3325	return false;
3326
3327	// Nameless functions like constructors cannot be entry points.
3328	if (!getIdentifier())
3329	return false;
3330
3331	return llvm::StringSwitch<bool>(getName())
3332	.Cases(S0: "main", // an ANSI console app
3333	S1: "wmain", // a Unicode console App
3334	S2: "WinMain", // an ANSI GUI app
3335	S3: "wWinMain", // a Unicode GUI app
3336	S4: "DllMain", // a DLL
3337	Value: true)
3338	.Default(Value: false);
3339	}
3340
3341	bool FunctionDecl::isReservedGlobalPlacementOperator() const {
3342	if (getDeclName().getNameKind() != DeclarationName::CXXOperatorName)
3343	return false;
3344	if (getDeclName().getCXXOverloadedOperator() != OO_New &&
3345	getDeclName().getCXXOverloadedOperator() != OO_Delete &&
3346	getDeclName().getCXXOverloadedOperator() != OO_Array_New &&
3347	getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
3348	return false;
3349
3350	if (!getDeclContext()->getRedeclContext()->isTranslationUnit())
3351	return false;
3352
3353	const auto *proto = getType()->castAs<FunctionProtoType>();
3354	if (proto->getNumParams() != 2 || proto->isVariadic())
3355	return false;
3356
3357	const ASTContext &Context =
3358	cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext())
3359	->getASTContext();
3360
3361	// The result type and first argument type are constant across all
3362	// these operators. The second argument must be exactly void*.
3363	return (proto->getParamType(1).getCanonicalType() == Context.VoidPtrTy);
3364	}
3365
3366	bool FunctionDecl::isReplaceableGlobalAllocationFunction(
3367	std::optional<unsigned> *AlignmentParam, bool *IsNothrow) const {
3368	if (getDeclName().getNameKind() != DeclarationName::CXXOperatorName)
3369	return false;
3370	if (getDeclName().getCXXOverloadedOperator() != OO_New &&
3371	getDeclName().getCXXOverloadedOperator() != OO_Delete &&
3372	getDeclName().getCXXOverloadedOperator() != OO_Array_New &&
3373	getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
3374	return false;
3375
3376	if (isa<CXXRecordDecl>(getDeclContext()))
3377	return false;
3378
3379	// This can only fail for an invalid 'operator new' declaration.
3380	if (!getDeclContext()->getRedeclContext()->isTranslationUnit())
3381	return false;
3382
3383	const auto *FPT = getType()->castAs<FunctionProtoType>();
3384	if (FPT->getNumParams() == 0 || FPT->getNumParams() > 4 || FPT->isVariadic())
3385	return false;
3386
3387	// If this is a single-parameter function, it must be a replaceable global
3388	// allocation or deallocation function.
3389	if (FPT->getNumParams() == 1)
3390	return true;
3391
3392	unsigned Params = 1;
3393	QualType Ty = FPT->getParamType(Params);
3394	const ASTContext &Ctx = getASTContext();
3395
3396	auto Consume = [&] {
3397	++Params;
3398	Ty = Params < FPT->getNumParams() ? FPT->getParamType(Params) : QualType();
3399	};
3400
3401	// In C++14, the next parameter can be a 'std::size_t' for sized delete.
3402	bool IsSizedDelete = false;
3403	if (Ctx.getLangOpts().SizedDeallocation &&
3404	(getDeclName().getCXXOverloadedOperator() == OO_Delete ||
3405	getDeclName().getCXXOverloadedOperator() == OO_Array_Delete) &&
3406	Ctx.hasSameType(T1: Ty, T2: Ctx.getSizeType())) {
3407	IsSizedDelete = true;
3408	Consume();
3409	}
3410
3411	// In C++17, the next parameter can be a 'std::align_val_t' for aligned
3412	// new/delete.
3413	if (Ctx.getLangOpts().AlignedAllocation && !Ty.isNull() && Ty->isAlignValT()) {
3414	Consume();
3415	if (AlignmentParam)
3416	*AlignmentParam = Params;
3417	}
3418
3419	// If this is not a sized delete, the next parameter can be a
3420	// 'const std::nothrow_t&'.
3421	if (!IsSizedDelete && !Ty.isNull() && Ty->isReferenceType()) {
3422	Ty = Ty->getPointeeType();
3423	if (Ty.getCVRQualifiers() != Qualifiers::Const)
3424	return false;
3425	if (Ty->isNothrowT()) {
3426	if (IsNothrow)
3427	*IsNothrow = true;
3428	Consume();
3429	}
3430	}
3431
3432	// Finally, recognize the not yet standard versions of new that take a
3433	// hot/cold allocation hint (__hot_cold_t). These are currently supported by
3434	// tcmalloc (see
3435	// https://github.com/google/tcmalloc/blob/220043886d4e2efff7a5702d5172cb8065253664/tcmalloc/malloc_extension.h#L53).
3436	if (!IsSizedDelete && !Ty.isNull() && Ty->isEnumeralType()) {
3437	QualType T = Ty;
3438	while (const auto *TD = T->getAs<TypedefType>())
3439	T = TD->getDecl()->getUnderlyingType();
3440	const IdentifierInfo *II =
3441	T->castAs<EnumType>()->getDecl()->getIdentifier();
3442	if (II && II->isStr(Str: "__hot_cold_t"))
3443	Consume();
3444	}
3445
3446	return Params == FPT->getNumParams();
3447	}
3448
3449	bool FunctionDecl::isInlineBuiltinDeclaration() const {
3450	if (!getBuiltinID())
3451	return false;
3452
3453	const FunctionDecl *Definition;
3454	if (!hasBody(Definition))
3455	return false;
3456
3457	if (!Definition->isInlineSpecified() ||
3458	!Definition->hasAttr<AlwaysInlineAttr>())
3459	return false;
3460
3461	ASTContext &Context = getASTContext();
3462	switch (Context.GetGVALinkageForFunction(FD: Definition)) {
3463	case GVA_Internal:
3464	case GVA_DiscardableODR:
3465	case GVA_StrongODR:
3466	return false;
3467	case GVA_AvailableExternally:
3468	case GVA_StrongExternal:
3469	return true;
3470	}
3471	llvm_unreachable("Unknown GVALinkage");
3472	}
3473
3474	bool FunctionDecl::isDestroyingOperatorDelete() const {
3475	// C++ P0722:
3476	// Within a class C, a single object deallocation function with signature
3477	// (T, std::destroying_delete_t, <more params>)
3478	// is a destroying operator delete.
3479	if (!isa<CXXMethodDecl>(Val: this) || getOverloadedOperator() != OO_Delete ||
3480	getNumParams() < 2)
3481	return false;
3482
3483	auto *RD = getParamDecl(i: 1)->getType()->getAsCXXRecordDecl();
3484	return RD && RD->isInStdNamespace() && RD->getIdentifier() &&
3485	RD->getIdentifier()->isStr("destroying_delete_t");
3486	}
3487
3488	LanguageLinkage FunctionDecl::getLanguageLinkage() const {
3489	return getDeclLanguageLinkage(D: *this);
3490	}
3491
3492	bool FunctionDecl::isExternC() const {
3493	return isDeclExternC(D: *this);
3494	}
3495
3496	bool FunctionDecl::isInExternCContext() const {
3497	if (hasAttr<OpenCLKernelAttr>())
3498	return true;
3499	return getLexicalDeclContext()->isExternCContext();
3500	}
3501
3502	bool FunctionDecl::isInExternCXXContext() const {
3503	return getLexicalDeclContext()->isExternCXXContext();
3504	}
3505
3506	bool FunctionDecl::isGlobal() const {
3507	if (const auto *Method = dyn_cast<CXXMethodDecl>(Val: this))
3508	return Method->isStatic();
3509
3510	if (getCanonicalDecl()->getStorageClass() == SC_Static)
3511	return false;
3512
3513	for (const DeclContext *DC = getDeclContext();
3514	DC->isNamespace();
3515	DC = DC->getParent()) {
3516	if (const auto *Namespace = cast<NamespaceDecl>(DC)) {
3517	if (!Namespace->getDeclName())
3518	return false;
3519	}
3520	}
3521
3522	return true;
3523	}
3524
3525	bool FunctionDecl::isNoReturn() const {
3526	if (hasAttr<NoReturnAttr>() || hasAttr<CXX11NoReturnAttr>() ||
3527	hasAttr<C11NoReturnAttr>())
3528	return true;
3529
3530	if (auto *FnTy = getType()->getAs<FunctionType>())
3531	return FnTy->getNoReturnAttr();
3532
3533	return false;
3534	}
3535
3536	bool FunctionDecl::isMemberLikeConstrainedFriend() const {
3537	// C++20 [temp.friend]p9:
3538	// A non-template friend declaration with a requires-clause [or]
3539	// a friend function template with a constraint that depends on a template
3540	// parameter from an enclosing template [...] does not declare the same
3541	// function or function template as a declaration in any other scope.
3542
3543	// If this isn't a friend then it's not a member-like constrained friend.
3544	if (!getFriendObjectKind()) {
3545	return false;
3546	}
3547
3548	if (!getDescribedFunctionTemplate()) {
3549	// If these friends don't have constraints, they aren't constrained, and
3550	// thus don't fall under temp.friend p9. Else the simple presence of a
3551	// constraint makes them unique.
3552	return getTrailingRequiresClause();
3553	}
3554
3555	return FriendConstraintRefersToEnclosingTemplate();
3556	}
3557
3558	MultiVersionKind FunctionDecl::getMultiVersionKind() const {
3559	if (hasAttr<TargetAttr>())
3560	return MultiVersionKind::Target;
3561	if (hasAttr<TargetVersionAttr>())
3562	return MultiVersionKind::TargetVersion;
3563	if (hasAttr<CPUDispatchAttr>())
3564	return MultiVersionKind::CPUDispatch;
3565	if (hasAttr<CPUSpecificAttr>())
3566	return MultiVersionKind::CPUSpecific;
3567	if (hasAttr<TargetClonesAttr>())
3568	return MultiVersionKind::TargetClones;
3569	return MultiVersionKind::None;
3570	}
3571
3572	bool FunctionDecl::isCPUDispatchMultiVersion() const {
3573	return isMultiVersion() && hasAttr<CPUDispatchAttr>();
3574	}
3575
3576	bool FunctionDecl::isCPUSpecificMultiVersion() const {
3577	return isMultiVersion() && hasAttr<CPUSpecificAttr>();
3578	}
3579
3580	bool FunctionDecl::isTargetMultiVersion() const {
3581	return isMultiVersion() &&
3582	(hasAttr<TargetAttr>() || hasAttr<TargetVersionAttr>());
3583	}
3584
3585	bool FunctionDecl::isTargetMultiVersionDefault() const {
3586	if (!isMultiVersion())
3587	return false;
3588	if (hasAttr<TargetAttr>())
3589	return getAttr<TargetAttr>()->isDefaultVersion();
3590	return hasAttr<TargetVersionAttr>() &&
3591	getAttr<TargetVersionAttr>()->isDefaultVersion();
3592	}
3593
3594	bool FunctionDecl::isTargetClonesMultiVersion() const {
3595	return isMultiVersion() && hasAttr<TargetClonesAttr>();
3596	}
3597
3598	bool FunctionDecl::isTargetVersionMultiVersion() const {
3599	return isMultiVersion() && hasAttr<TargetVersionAttr>();
3600	}
3601
3602	void
3603	FunctionDecl::setPreviousDeclaration(FunctionDecl *PrevDecl) {
3604	redeclarable_base::setPreviousDecl(PrevDecl);
3605
3606	if (FunctionTemplateDecl *FunTmpl = getDescribedFunctionTemplate()) {
3607	FunctionTemplateDecl *PrevFunTmpl
3608	= PrevDecl? PrevDecl->getDescribedFunctionTemplate() : nullptr;
3609	assert((!PrevDecl || PrevFunTmpl) && "Function/function template mismatch");
3610	FunTmpl->setPreviousDecl(PrevFunTmpl);
3611	}
3612
3613	if (PrevDecl && PrevDecl->isInlined())
3614	setImplicitlyInline(true);
3615	}
3616
3617	FunctionDecl *FunctionDecl::getCanonicalDecl() { return getFirstDecl(); }
3618
3619	/// Returns a value indicating whether this function corresponds to a builtin
3620	/// function.
3621	///
3622	/// The function corresponds to a built-in function if it is declared at
3623	/// translation scope or within an extern "C" block and its name matches with
3624	/// the name of a builtin. The returned value will be 0 for functions that do
3625	/// not correspond to a builtin, a value of type \c Builtin::ID if in the
3626	/// target-independent range \c [1,Builtin::First), or a target-specific builtin
3627	/// value.
3628	///
3629	/// \param ConsiderWrapperFunctions If true, we should consider wrapper
3630	/// functions as their wrapped builtins. This shouldn't be done in general, but
3631	/// it's useful in Sema to diagnose calls to wrappers based on their semantics.
3632	unsigned FunctionDecl::getBuiltinID(bool ConsiderWrapperFunctions) const {
3633	unsigned BuiltinID = 0;
3634
3635	if (const auto *ABAA = getAttr<ArmBuiltinAliasAttr>()) {
3636	BuiltinID = ABAA->getBuiltinName()->getBuiltinID();
3637	} else if (const auto *BAA = getAttr<BuiltinAliasAttr>()) {
3638	BuiltinID = BAA->getBuiltinName()->getBuiltinID();
3639	} else if (const auto *A = getAttr<BuiltinAttr>()) {
3640	BuiltinID = A->getID();
3641	}
3642
3643	if (!BuiltinID)
3644	return 0;
3645
3646	// If the function is marked "overloadable", it has a different mangled name
3647	// and is not the C library function.
3648	if (!ConsiderWrapperFunctions && hasAttr<OverloadableAttr>() &&
3649	(!hasAttr<ArmBuiltinAliasAttr>() && !hasAttr<BuiltinAliasAttr>()))
3650	return 0;
3651
3652	const ASTContext &Context = getASTContext();
3653	if (!Context.BuiltinInfo.isPredefinedLibFunction(ID: BuiltinID))
3654	return BuiltinID;
3655
3656	// This function has the name of a known C library
3657	// function. Determine whether it actually refers to the C library
3658	// function or whether it just has the same name.
3659
3660	// If this is a static function, it's not a builtin.
3661	if (!ConsiderWrapperFunctions && getStorageClass() == SC_Static)
3662	return 0;
3663
3664	// OpenCL v1.2 s6.9.f - The library functions defined in
3665	// the C99 standard headers are not available.
3666	if (Context.getLangOpts().OpenCL &&
3667	Context.BuiltinInfo.isPredefinedLibFunction(ID: BuiltinID))
3668	return 0;
3669
3670	// CUDA does not have device-side standard library. printf and malloc are the
3671	// only special cases that are supported by device-side runtime.
3672	if (Context.getLangOpts().CUDA && hasAttr<CUDADeviceAttr>() &&
3673	!hasAttr<CUDAHostAttr>() &&
3674	!(BuiltinID == Builtin::BIprintf || BuiltinID == Builtin::BImalloc))
3675	return 0;
3676
3677	// As AMDGCN implementation of OpenMP does not have a device-side standard
3678	// library, none of the predefined library functions except printf and malloc
3679	// should be treated as a builtin i.e. 0 should be returned for them.
3680	if (Context.getTargetInfo().getTriple().isAMDGCN() &&
3681	Context.getLangOpts().OpenMPIsTargetDevice &&
3682	Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
3683	!(BuiltinID == Builtin::BIprintf || BuiltinID == Builtin::BImalloc))
3684	return 0;
3685
3686	return BuiltinID;
3687	}
3688
3689	/// getNumParams - Return the number of parameters this function must have
3690	/// based on its FunctionType. This is the length of the ParamInfo array
3691	/// after it has been created.
3692	unsigned FunctionDecl::getNumParams() const {
3693	const auto *FPT = getType()->getAs<FunctionProtoType>();
3694	return FPT ? FPT->getNumParams() : 0;
3695	}
3696
3697	void FunctionDecl::setParams(ASTContext &C,
3698	ArrayRef<ParmVarDecl *> NewParamInfo) {
3699	assert(!ParamInfo && "Already has param info!");
3700	assert(NewParamInfo.size() == getNumParams() && "Parameter count mismatch!");
3701
3702	// Zero params -> null pointer.
3703	if (!NewParamInfo.empty()) {
3704	ParamInfo = new (C) ParmVarDecl*[NewParamInfo.size()];
3705	std::copy(first: NewParamInfo.begin(), last: NewParamInfo.end(), result: ParamInfo);
3706	}
3707	}
3708
3709	/// getMinRequiredArguments - Returns the minimum number of arguments
3710	/// needed to call this function. This may be fewer than the number of
3711	/// function parameters, if some of the parameters have default
3712	/// arguments (in C++) or are parameter packs (C++11).
3713	unsigned FunctionDecl::getMinRequiredArguments() const {
3714	if (!getASTContext().getLangOpts().CPlusPlus)
3715	return getNumParams();
3716
3717	// Note that it is possible for a parameter with no default argument to
3718	// follow a parameter with a default argument.
3719	unsigned NumRequiredArgs = 0;
3720	unsigned MinParamsSoFar = 0;
3721	for (auto *Param : parameters()) {
3722	if (!Param->isParameterPack()) {
3723	++MinParamsSoFar;
3724	if (!Param->hasDefaultArg())
3725	NumRequiredArgs = MinParamsSoFar;
3726	}
3727	}
3728	return NumRequiredArgs;
3729	}
3730
3731	bool FunctionDecl::hasCXXExplicitFunctionObjectParameter() const {
3732	return getNumParams() != 0 && getParamDecl(i: 0)->isExplicitObjectParameter();
3733	}
3734
3735	unsigned FunctionDecl::getNumNonObjectParams() const {
3736	return getNumParams() -
3737	static_cast<unsigned>(hasCXXExplicitFunctionObjectParameter());
3738	}
3739
3740	unsigned FunctionDecl::getMinRequiredExplicitArguments() const {
3741	return getMinRequiredArguments() -
3742	static_cast<unsigned>(hasCXXExplicitFunctionObjectParameter());
3743	}
3744
3745	bool FunctionDecl::hasOneParamOrDefaultArgs() const {
3746	return getNumParams() == 1 ||
3747	(getNumParams() > 1 &&
3748	llvm::all_of(Range: llvm::drop_begin(RangeOrContainer: parameters()),
3749	P: [](ParmVarDecl *P) { return P->hasDefaultArg(); }));
3750	}
3751
3752	/// The combination of the extern and inline keywords under MSVC forces
3753	/// the function to be required.
3754	///
3755	/// Note: This function assumes that we will only get called when isInlined()
3756	/// would return true for this FunctionDecl.
3757	bool FunctionDecl::isMSExternInline() const {
3758	assert(isInlined() && "expected to get called on an inlined function!");
3759
3760	const ASTContext &Context = getASTContext();
3761	if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
3762	!hasAttr<DLLExportAttr>())
3763	return false;
3764
3765	for (const FunctionDecl *FD = getMostRecentDecl(); FD;
3766	FD = FD->getPreviousDecl())
3767	if (!FD->isImplicit() && FD->getStorageClass() == SC_Extern)
3768	return true;
3769
3770	return false;
3771	}
3772
3773	static bool redeclForcesDefMSVC(const FunctionDecl *Redecl) {
3774	if (Redecl->getStorageClass() != SC_Extern)
3775	return false;
3776
3777	for (const FunctionDecl *FD = Redecl->getPreviousDecl(); FD;
3778	FD = FD->getPreviousDecl())
3779	if (!FD->isImplicit() && FD->getStorageClass() == SC_Extern)
3780	return false;
3781
3782	return true;
3783	}
3784
3785	static bool RedeclForcesDefC99(const FunctionDecl *Redecl) {
3786	// Only consider file-scope declarations in this test.
3787	if (!Redecl->getLexicalDeclContext()->isTranslationUnit())
3788	return false;
3789
3790	// Only consider explicit declarations; the presence of a builtin for a
3791	// libcall shouldn't affect whether a definition is externally visible.
3792	if (Redecl->isImplicit())
3793	return false;
3794
3795	if (!Redecl->isInlineSpecified() || Redecl->getStorageClass() == SC_Extern)
3796	return true; // Not an inline definition
3797
3798	return false;
3799	}
3800
3801	/// For a function declaration in C or C++, determine whether this
3802	/// declaration causes the definition to be externally visible.
3803	///
3804	/// For instance, this determines if adding the current declaration to the set
3805	/// of redeclarations of the given functions causes
3806	/// isInlineDefinitionExternallyVisible to change from false to true.
3807	bool FunctionDecl::doesDeclarationForceExternallyVisibleDefinition() const {
3808	assert(!doesThisDeclarationHaveABody() &&
3809	"Must have a declaration without a body.");
3810
3811	const ASTContext &Context = getASTContext();
3812
3813	if (Context.getLangOpts().MSVCCompat) {
3814	const FunctionDecl *Definition;
3815	if (hasBody(Definition) && Definition->isInlined() &&
3816	redeclForcesDefMSVC(Redecl: this))
3817	return true;
3818	}
3819
3820	if (Context.getLangOpts().CPlusPlus)
3821	return false;
3822
3823	if (Context.getLangOpts().GNUInline || hasAttr<GNUInlineAttr>()) {
3824	// With GNU inlining, a declaration with 'inline' but not 'extern', forces
3825	// an externally visible definition.
3826	//
3827	// FIXME: What happens if gnu_inline gets added on after the first
3828	// declaration?
3829	if (!isInlineSpecified() || getStorageClass() == SC_Extern)
3830	return false;
3831
3832	const FunctionDecl *Prev = this;
3833	bool FoundBody = false;
3834	while ((Prev = Prev->getPreviousDecl())) {
3835	FoundBody |= Prev->doesThisDeclarationHaveABody();
3836
3837	if (Prev->doesThisDeclarationHaveABody()) {
3838	// If it's not the case that both 'inline' and 'extern' are
3839	// specified on the definition, then it is always externally visible.
3840	if (!Prev->isInlineSpecified() ||
3841	Prev->getStorageClass() != SC_Extern)
3842	return false;
3843	} else if (Prev->isInlineSpecified() &&
3844	Prev->getStorageClass() != SC_Extern) {
3845	return false;
3846	}
3847	}
3848	return FoundBody;
3849	}
3850
3851	// C99 6.7.4p6:
3852	// [...] If all of the file scope declarations for a function in a
3853	// translation unit include the inline function specifier without extern,
3854	// then the definition in that translation unit is an inline definition.
3855	if (isInlineSpecified() && getStorageClass() != SC_Extern)
3856	return false;
3857	const FunctionDecl *Prev = this;
3858	bool FoundBody = false;
3859	while ((Prev = Prev->getPreviousDecl())) {
3860	FoundBody |= Prev->doesThisDeclarationHaveABody();
3861	if (RedeclForcesDefC99(Redecl: Prev))
3862	return false;
3863	}
3864	return FoundBody;
3865	}
3866
3867	FunctionTypeLoc FunctionDecl::getFunctionTypeLoc() const {
3868	const TypeSourceInfo *TSI = getTypeSourceInfo();
3869	return TSI ? TSI->getTypeLoc().IgnoreParens().getAs<FunctionTypeLoc>()
3870	: FunctionTypeLoc();
3871	}
3872
3873	SourceRange FunctionDecl::getReturnTypeSourceRange() const {
3874	FunctionTypeLoc FTL = getFunctionTypeLoc();
3875	if (!FTL)
3876	return SourceRange();
3877
3878	// Skip self-referential return types.
3879	const SourceManager &SM = getASTContext().getSourceManager();
3880	SourceRange RTRange = FTL.getReturnLoc().getSourceRange();
3881	SourceLocation Boundary = getNameInfo().getBeginLoc();
3882	if (RTRange.isInvalid() || Boundary.isInvalid() ||
3883	!SM.isBeforeInTranslationUnit(LHS: RTRange.getEnd(), RHS: Boundary))
3884	return SourceRange();
3885
3886	return RTRange;
3887	}
3888
3889	SourceRange FunctionDecl::getParametersSourceRange() const {
3890	unsigned NP = getNumParams();
3891	SourceLocation EllipsisLoc = getEllipsisLoc();
3892
3893	if (NP == 0 && EllipsisLoc.isInvalid())
3894	return SourceRange();
3895
3896	SourceLocation Begin =
3897	NP > 0 ? ParamInfo[0]->getSourceRange().getBegin() : EllipsisLoc;
3898	SourceLocation End = EllipsisLoc.isValid()
3899	? EllipsisLoc
3900	: ParamInfo[NP - 1]->getSourceRange().getEnd();
3901
3902	return SourceRange(Begin, End);
3903	}
3904
3905	SourceRange FunctionDecl::getExceptionSpecSourceRange() const {
3906	FunctionTypeLoc FTL = getFunctionTypeLoc();
3907	return FTL ? FTL.getExceptionSpecRange() : SourceRange();
3908	}
3909
3910	/// For an inline function definition in C, or for a gnu_inline function
3911	/// in C++, determine whether the definition will be externally visible.
3912	///
3913	/// Inline function definitions are always available for inlining optimizations.
3914	/// However, depending on the language dialect, declaration specifiers, and
3915	/// attributes, the definition of an inline function may or may not be
3916	/// "externally" visible to other translation units in the program.
3917	///
3918	/// In C99, inline definitions are not externally visible by default. However,
3919	/// if even one of the global-scope declarations is marked "extern inline", the
3920	/// inline definition becomes externally visible (C99 6.7.4p6).
3921	///
3922	/// In GNU89 mode, or if the gnu_inline attribute is attached to the function
3923	/// definition, we use the GNU semantics for inline, which are nearly the
3924	/// opposite of C99 semantics. In particular, "inline" by itself will create
3925	/// an externally visible symbol, but "extern inline" will not create an
3926	/// externally visible symbol.
3927	bool FunctionDecl::isInlineDefinitionExternallyVisible() const {
3928	assert((doesThisDeclarationHaveABody() || willHaveBody() ||
3929	hasAttr<AliasAttr>()) &&
3930	"Must be a function definition");
3931	assert(isInlined() && "Function must be inline");
3932	ASTContext &Context = getASTContext();
3933
3934	if (Context.getLangOpts().GNUInline || hasAttr<GNUInlineAttr>()) {
3935	// Note: If you change the logic here, please change
3936	// doesDeclarationForceExternallyVisibleDefinition as well.
3937	//
3938	// If it's not the case that both 'inline' and 'extern' are
3939	// specified on the definition, then this inline definition is
3940	// externally visible.
3941	if (Context.getLangOpts().CPlusPlus)
3942	return false;
3943	if (!(isInlineSpecified() && getStorageClass() == SC_Extern))
3944	return true;
3945
3946	// If any declaration is 'inline' but not 'extern', then this definition
3947	// is externally visible.
3948	for (auto *Redecl : redecls()) {
3949	if (Redecl->isInlineSpecified() &&
3950	Redecl->getStorageClass() != SC_Extern)
3951	return true;
3952	}
3953
3954	return false;
3955	}
3956
3957	// The rest of this function is C-only.
3958	assert(!Context.getLangOpts().CPlusPlus &&
3959	"should not use C inline rules in C++");
3960
3961	// C99 6.7.4p6:
3962	// [...] If all of the file scope declarations for a function in a
3963	// translation unit include the inline function specifier without extern,
3964	// then the definition in that translation unit is an inline definition.
3965	for (auto *Redecl : redecls()) {
3966	if (RedeclForcesDefC99(Redecl))
3967	return true;
3968	}
3969
3970	// C99 6.7.4p6:
3971	// An inline definition does not provide an external definition for the
3972	// function, and does not forbid an external definition in another
3973	// translation unit.
3974	return false;
3975	}
3976
3977	/// getOverloadedOperator - Which C++ overloaded operator this
3978	/// function represents, if any.
3979	OverloadedOperatorKind FunctionDecl::getOverloadedOperator() const {
3980	if (getDeclName().getNameKind() == DeclarationName::CXXOperatorName)
3981	return getDeclName().getCXXOverloadedOperator();
3982	return OO_None;
3983	}
3984
3985	/// getLiteralIdentifier - The literal suffix identifier this function
3986	/// represents, if any.
3987	const IdentifierInfo *FunctionDecl::getLiteralIdentifier() const {
3988	if (getDeclName().getNameKind() == DeclarationName::CXXLiteralOperatorName)
3989	return getDeclName().getCXXLiteralIdentifier();
3990	return nullptr;
3991	}
3992
3993	FunctionDecl::TemplatedKind FunctionDecl::getTemplatedKind() const {
3994	if (TemplateOrSpecialization.isNull())
3995	return TK_NonTemplate;
3996	if (const auto *ND = TemplateOrSpecialization.dyn_cast<NamedDecl *>()) {
3997	if (isa<FunctionDecl>(Val: ND))
3998	return TK_DependentNonTemplate;
3999	assert(isa<FunctionTemplateDecl>(ND) &&
4000	"No other valid types in NamedDecl");
4001	return TK_FunctionTemplate;
4002	}
4003	if (TemplateOrSpecialization.is<MemberSpecializationInfo *>())
4004	return TK_MemberSpecialization;
4005	if (TemplateOrSpecialization.is<FunctionTemplateSpecializationInfo *>())
4006	return TK_FunctionTemplateSpecialization;
4007	if (TemplateOrSpecialization.is
4008	<DependentFunctionTemplateSpecializationInfo*>())
4009	return TK_DependentFunctionTemplateSpecialization;
4010
4011	llvm_unreachable("Did we miss a TemplateOrSpecialization type?");
4012	}
4013
4014	FunctionDecl *FunctionDecl::getInstantiatedFromMemberFunction() const {
4015	if (MemberSpecializationInfo *Info = getMemberSpecializationInfo())
4016	return cast<FunctionDecl>(Val: Info->getInstantiatedFrom());
4017
4018	return nullptr;
4019	}
4020
4021	MemberSpecializationInfo *FunctionDecl::getMemberSpecializationInfo() const {
4022	if (auto *MSI =
4023	TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo *>())
4024	return MSI;
4025	if (auto *FTSI = TemplateOrSpecialization
4026	.dyn_cast<FunctionTemplateSpecializationInfo *>())
4027	return FTSI->getMemberSpecializationInfo();
4028	return nullptr;
4029	}
4030
4031	void
4032	FunctionDecl::setInstantiationOfMemberFunction(ASTContext &C,
4033	FunctionDecl *FD,
4034	TemplateSpecializationKind TSK) {
4035	assert(TemplateOrSpecialization.isNull() &&
4036	"Member function is already a specialization");
4037	MemberSpecializationInfo *Info
4038	= new (C) MemberSpecializationInfo(FD, TSK);
4039	TemplateOrSpecialization = Info;
4040	}
4041
4042	FunctionTemplateDecl *FunctionDecl::getDescribedFunctionTemplate() const {
4043	return dyn_cast_if_present<FunctionTemplateDecl>(
4044	Val: TemplateOrSpecialization.dyn_cast<NamedDecl *>());
4045	}
4046
4047	void FunctionDecl::setDescribedFunctionTemplate(
4048	FunctionTemplateDecl *Template) {
4049	assert(TemplateOrSpecialization.isNull() &&
4050	"Member function is already a specialization");
4051	TemplateOrSpecialization = Template;
4052	}
4053
4054	bool FunctionDecl::isFunctionTemplateSpecialization() const {
4055	return TemplateOrSpecialization.is<FunctionTemplateSpecializationInfo *>() ||
4056	TemplateOrSpecialization
4057	.is<DependentFunctionTemplateSpecializationInfo *>();
4058	}
4059
4060	void FunctionDecl::setInstantiatedFromDecl(FunctionDecl *FD) {
4061	assert(TemplateOrSpecialization.isNull() &&
4062	"Function is already a specialization");
4063	TemplateOrSpecialization = FD;
4064	}
4065
4066	FunctionDecl *FunctionDecl::getInstantiatedFromDecl() const {
4067	return dyn_cast_if_present<FunctionDecl>(
4068	Val: TemplateOrSpecialization.dyn_cast<NamedDecl *>());
4069	}
4070
4071	bool FunctionDecl::isImplicitlyInstantiable() const {
4072	// If the function is invalid, it can't be implicitly instantiated.
4073	if (isInvalidDecl())
4074	return false;
4075
4076	switch (getTemplateSpecializationKindForInstantiation()) {
4077	case TSK_Undeclared:
4078	case TSK_ExplicitInstantiationDefinition:
4079	case TSK_ExplicitSpecialization:
4080	return false;
4081
4082	case TSK_ImplicitInstantiation:
4083	return true;
4084
4085	case TSK_ExplicitInstantiationDeclaration:
4086	// Handled below.
4087	break;
4088	}
4089
4090	// Find the actual template from which we will instantiate.
4091	const FunctionDecl *PatternDecl = getTemplateInstantiationPattern();
4092	bool HasPattern = false;
4093	if (PatternDecl)
4094	HasPattern = PatternDecl->hasBody(Definition&: PatternDecl);
4095
4096	// C++0x [temp.explicit]p9:
4097	// Except for inline functions, other explicit instantiation declarations
4098	// have the effect of suppressing the implicit instantiation of the entity
4099	// to which they refer.
4100	if (!HasPattern || !PatternDecl)
4101	return true;
4102
4103	return PatternDecl->isInlined();
4104	}
4105
4106	bool FunctionDecl::isTemplateInstantiation() const {
4107	// FIXME: Remove this, it's not clear what it means. (Which template
4108	// specialization kind?)
4109	return clang::isTemplateInstantiation(Kind: getTemplateSpecializationKind());
4110	}
4111
4112	FunctionDecl *
4113	FunctionDecl::getTemplateInstantiationPattern(bool ForDefinition) const {
4114	// If this is a generic lambda call operator specialization, its
4115	// instantiation pattern is always its primary template's pattern
4116	// even if its primary template was instantiated from another
4117	// member template (which happens with nested generic lambdas).
4118	// Since a lambda's call operator's body is transformed eagerly,
4119	// we don't have to go hunting for a prototype definition template
4120	// (i.e. instantiated-from-member-template) to use as an instantiation
4121	// pattern.
4122
4123	if (isGenericLambdaCallOperatorSpecialization(
4124	MD: dyn_cast<CXXMethodDecl>(Val: this))) {
4125	assert(getPrimaryTemplate() && "not a generic lambda call operator?");
4126	return getDefinitionOrSelf(D: getPrimaryTemplate()->getTemplatedDecl());
4127	}
4128
4129	// Check for a declaration of this function that was instantiated from a
4130	// friend definition.
4131	const FunctionDecl *FD = nullptr;
4132	if (!isDefined(Definition&: FD, /*CheckForPendingFriendDefinition=*/true))
4133	FD = this;
4134
4135	if (MemberSpecializationInfo *Info = FD->getMemberSpecializationInfo()) {
4136	if (ForDefinition &&
4137	!clang::isTemplateInstantiation(Kind: Info->getTemplateSpecializationKind()))
4138	return nullptr;
4139	return getDefinitionOrSelf(D: cast<FunctionDecl>(Val: Info->getInstantiatedFrom()));
4140	}
4141
4142	if (ForDefinition &&
4143	!clang::isTemplateInstantiation(Kind: getTemplateSpecializationKind()))
4144	return nullptr;
4145
4146	if (FunctionTemplateDecl *Primary = getPrimaryTemplate()) {
4147	// If we hit a point where the user provided a specialization of this
4148	// template, we're done looking.
4149	while (!ForDefinition || !Primary->isMemberSpecialization()) {
4150	auto *NewPrimary = Primary->getInstantiatedFromMemberTemplate();
4151	if (!NewPrimary)
4152	break;
4153	Primary = NewPrimary;
4154	}
4155
4156	return getDefinitionOrSelf(D: Primary->getTemplatedDecl());
4157	}
4158
4159	return nullptr;
4160	}
4161
4162	FunctionTemplateDecl *FunctionDecl::getPrimaryTemplate() const {
4163	if (FunctionTemplateSpecializationInfo *Info
4164	= TemplateOrSpecialization
4165	.dyn_cast<FunctionTemplateSpecializationInfo*>()) {
4166	return Info->getTemplate();
4167	}
4168	return nullptr;
4169	}
4170
4171	FunctionTemplateSpecializationInfo *
4172	FunctionDecl::getTemplateSpecializationInfo() const {
4173	return TemplateOrSpecialization
4174	.dyn_cast<FunctionTemplateSpecializationInfo *>();
4175	}
4176
4177	const TemplateArgumentList *
4178	FunctionDecl::getTemplateSpecializationArgs() const {
4179	if (FunctionTemplateSpecializationInfo *Info
4180	= TemplateOrSpecialization
4181	.dyn_cast<FunctionTemplateSpecializationInfo*>()) {
4182	return Info->TemplateArguments;
4183	}
4184	return nullptr;
4185	}
4186
4187	const ASTTemplateArgumentListInfo *
4188	FunctionDecl::getTemplateSpecializationArgsAsWritten() const {
4189	if (FunctionTemplateSpecializationInfo *Info
4190	= TemplateOrSpecialization
4191	.dyn_cast<FunctionTemplateSpecializationInfo*>()) {
4192	return Info->TemplateArgumentsAsWritten;
4193	}
4194	if (DependentFunctionTemplateSpecializationInfo *Info =
4195	TemplateOrSpecialization
4196	.dyn_cast<DependentFunctionTemplateSpecializationInfo *>()) {
4197	return Info->TemplateArgumentsAsWritten;
4198	}
4199	return nullptr;
4200	}
4201
4202	void
4203	FunctionDecl::setFunctionTemplateSpecialization(ASTContext &C,
4204	FunctionTemplateDecl *Template,
4205	const TemplateArgumentList *TemplateArgs,
4206	void *InsertPos,
4207	TemplateSpecializationKind TSK,
4208	const TemplateArgumentListInfo *TemplateArgsAsWritten,
4209	SourceLocation PointOfInstantiation) {
4210	assert((TemplateOrSpecialization.isNull() ||
4211	TemplateOrSpecialization.is<MemberSpecializationInfo *>()) &&
4212	"Member function is already a specialization");
4213	assert(TSK != TSK_Undeclared &&
4214	"Must specify the type of function template specialization");
4215	assert((TemplateOrSpecialization.isNull() ||
4216	getFriendObjectKind() != FOK_None ||
4217	TSK == TSK_ExplicitSpecialization) &&
4218	"Member specialization must be an explicit specialization");
4219	FunctionTemplateSpecializationInfo *Info =
4220	FunctionTemplateSpecializationInfo::Create(
4221	C, FD: this, Template, TSK, TemplateArgs, TemplateArgsAsWritten,
4222	POI: PointOfInstantiation,
4223	MSInfo: TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo *>());
4224	TemplateOrSpecialization = Info;
4225	Template->addSpecialization(Info, InsertPos);
4226	}
4227
4228	void FunctionDecl::setDependentTemplateSpecialization(
4229	ASTContext &Context, const UnresolvedSetImpl &Templates,
4230	const TemplateArgumentListInfo *TemplateArgs) {
4231	assert(TemplateOrSpecialization.isNull());
4232	DependentFunctionTemplateSpecializationInfo *Info =
4233	DependentFunctionTemplateSpecializationInfo::Create(Context, Candidates: Templates,
4234	TemplateArgs);
4235	TemplateOrSpecialization = Info;
4236	}
4237
4238	DependentFunctionTemplateSpecializationInfo *
4239	FunctionDecl::getDependentSpecializationInfo() const {
4240	return TemplateOrSpecialization
4241	.dyn_cast<DependentFunctionTemplateSpecializationInfo *>();
4242	}
4243
4244	DependentFunctionTemplateSpecializationInfo *
4245	DependentFunctionTemplateSpecializationInfo::Create(
4246	ASTContext &Context, const UnresolvedSetImpl &Candidates,
4247	const TemplateArgumentListInfo *TArgs) {
4248	const auto *TArgsWritten =
4249	TArgs ? ASTTemplateArgumentListInfo::Create(C: Context, List: *TArgs) : nullptr;
4250	return new (Context.Allocate(
4251	Size: totalSizeToAlloc<FunctionTemplateDecl *>(Counts: Candidates.size())))
4252	DependentFunctionTemplateSpecializationInfo(Candidates, TArgsWritten);
4253	}
4254
4255	DependentFunctionTemplateSpecializationInfo::
4256	DependentFunctionTemplateSpecializationInfo(
4257	const UnresolvedSetImpl &Candidates,
4258	const ASTTemplateArgumentListInfo *TemplateArgsWritten)
4259	: NumCandidates(Candidates.size()),
4260	TemplateArgumentsAsWritten(TemplateArgsWritten) {
4261	std::transform(first: Candidates.begin(), last: Candidates.end(),
4262	result: getTrailingObjects<FunctionTemplateDecl *>(),
4263	unary_op: [](NamedDecl *ND) {
4264	return cast<FunctionTemplateDecl>(Val: ND->getUnderlyingDecl());
4265	});
4266	}
4267
4268	TemplateSpecializationKind FunctionDecl::getTemplateSpecializationKind() const {
4269	// For a function template specialization, query the specialization
4270	// information object.
4271	if (FunctionTemplateSpecializationInfo *FTSInfo =
4272	TemplateOrSpecialization
4273	.dyn_cast<FunctionTemplateSpecializationInfo *>())
4274	return FTSInfo->getTemplateSpecializationKind();
4275
4276	if (MemberSpecializationInfo *MSInfo =
4277	TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo *>())
4278	return MSInfo->getTemplateSpecializationKind();
4279
4280	// A dependent function template specialization is an explicit specialization,
4281	// except when it's a friend declaration.
4282	if (TemplateOrSpecialization
4283	.is<DependentFunctionTemplateSpecializationInfo *>() &&
4284	getFriendObjectKind() == FOK_None)
4285	return TSK_ExplicitSpecialization;
4286
4287	return TSK_Undeclared;
4288	}
4289
4290	TemplateSpecializationKind
4291	FunctionDecl::getTemplateSpecializationKindForInstantiation() const {
4292	// This is the same as getTemplateSpecializationKind(), except that for a
4293	// function that is both a function template specialization and a member
4294	// specialization, we prefer the member specialization information. Eg:
4295	//
4296	// template<typename T> struct A {
4297	// template<typename U> void f() {}
4298	// template<> void f<int>() {}
4299	// };
4300	//
4301	// Within the templated CXXRecordDecl, A<T>::f<int> is a dependent function
4302	// template specialization; both getTemplateSpecializationKind() and
4303	// getTemplateSpecializationKindForInstantiation() will return
4304	// TSK_ExplicitSpecialization.
4305	//
4306	// For A<int>::f<int>():
4307	// * getTemplateSpecializationKind() will return TSK_ExplicitSpecialization
4308	// * getTemplateSpecializationKindForInstantiation() will return
4309	// TSK_ImplicitInstantiation
4310	//
4311	// This reflects the facts that A<int>::f<int> is an explicit specialization
4312	// of A<int>::f, and that A<int>::f<int> should be implicitly instantiated
4313	// from A::f<int> if a definition is needed.
4314	if (FunctionTemplateSpecializationInfo *FTSInfo =
4315	TemplateOrSpecialization
4316	.dyn_cast<FunctionTemplateSpecializationInfo *>()) {
4317	if (auto *MSInfo = FTSInfo->getMemberSpecializationInfo())
4318	return MSInfo->getTemplateSpecializationKind();
4319	return FTSInfo->getTemplateSpecializationKind();
4320	}
4321
4322	if (MemberSpecializationInfo *MSInfo =
4323	TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo *>())
4324	return MSInfo->getTemplateSpecializationKind();
4325
4326	if (TemplateOrSpecialization
4327	.is<DependentFunctionTemplateSpecializationInfo *>() &&
4328	getFriendObjectKind() == FOK_None)
4329	return TSK_ExplicitSpecialization;
4330
4331	return TSK_Undeclared;
4332	}
4333
4334	void
4335	FunctionDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
4336	SourceLocation PointOfInstantiation) {
4337	if (FunctionTemplateSpecializationInfo *FTSInfo
4338	= TemplateOrSpecialization.dyn_cast<
4339	FunctionTemplateSpecializationInfo*>()) {
4340	FTSInfo->setTemplateSpecializationKind(TSK);
4341	if (TSK != TSK_ExplicitSpecialization &&
4342	PointOfInstantiation.isValid() &&
4343	FTSInfo->getPointOfInstantiation().isInvalid()) {
4344	FTSInfo->setPointOfInstantiation(PointOfInstantiation);
4345	if (ASTMutationListener *L = getASTContext().getASTMutationListener())
4346	L->InstantiationRequested(this);
4347	}
4348	} else if (MemberSpecializationInfo *MSInfo
4349	= TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo*>()) {
4350	MSInfo->setTemplateSpecializationKind(TSK);
4351	if (TSK != TSK_ExplicitSpecialization &&
4352	PointOfInstantiation.isValid() &&
4353	MSInfo->getPointOfInstantiation().isInvalid()) {
4354	MSInfo->setPointOfInstantiation(PointOfInstantiation);
4355	if (ASTMutationListener *L = getASTContext().getASTMutationListener())
4356	L->InstantiationRequested(this);
4357	}
4358	} else
4359	llvm_unreachable("Function cannot have a template specialization kind");
4360	}
4361
4362	SourceLocation FunctionDecl::getPointOfInstantiation() const {
4363	if (FunctionTemplateSpecializationInfo *FTSInfo
4364	= TemplateOrSpecialization.dyn_cast<
4365	FunctionTemplateSpecializationInfo*>())
4366	return FTSInfo->getPointOfInstantiation();
4367	if (MemberSpecializationInfo *MSInfo =
4368	TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo *>())
4369	return MSInfo->getPointOfInstantiation();
4370
4371	return SourceLocation();
4372	}
4373
4374	bool FunctionDecl::isOutOfLine() const {
4375	if (Decl::isOutOfLine())
4376	return true;
4377
4378	// If this function was instantiated from a member function of a
4379	// class template, check whether that member function was defined out-of-line.
4380	if (FunctionDecl *FD = getInstantiatedFromMemberFunction()) {
4381	const FunctionDecl *Definition;
4382	if (FD->hasBody(Definition))
4383	return Definition->isOutOfLine();
4384	}
4385
4386	// If this function was instantiated from a function template,
4387	// check whether that function template was defined out-of-line.
4388	if (FunctionTemplateDecl *FunTmpl = getPrimaryTemplate()) {
4389	const FunctionDecl *Definition;
4390	if (FunTmpl->getTemplatedDecl()->hasBody(Definition))
4391	return Definition->isOutOfLine();
4392	}
4393
4394	return false;
4395	}
4396
4397	SourceRange FunctionDecl::getSourceRange() const {
4398	return SourceRange(getOuterLocStart(), EndRangeLoc);
4399	}
4400
4401	unsigned FunctionDecl::getMemoryFunctionKind() const {
4402	IdentifierInfo *FnInfo = getIdentifier();
4403
4404	if (!FnInfo)
4405	return 0;
4406
4407	// Builtin handling.
4408	switch (getBuiltinID()) {
4409	case Builtin::BI__builtin_memset:
4410	case Builtin::BI__builtin___memset_chk:
4411	case Builtin::BImemset:
4412	return Builtin::BImemset;
4413
4414	case Builtin::BI__builtin_memcpy:
4415	case Builtin::BI__builtin___memcpy_chk:
4416	case Builtin::BImemcpy:
4417	return Builtin::BImemcpy;
4418
4419	case Builtin::BI__builtin_mempcpy:
4420	case Builtin::BI__builtin___mempcpy_chk:
4421	case Builtin::BImempcpy:
4422	return Builtin::BImempcpy;
4423
4424	case Builtin::BI__builtin_memmove:
4425	case Builtin::BI__builtin___memmove_chk:
4426	case Builtin::BImemmove:
4427	return Builtin::BImemmove;
4428
4429	case Builtin::BIstrlcpy:
4430	case Builtin::BI__builtin___strlcpy_chk:
4431	return Builtin::BIstrlcpy;
4432
4433	case Builtin::BIstrlcat:
4434	case Builtin::BI__builtin___strlcat_chk:
4435	return Builtin::BIstrlcat;
4436
4437	case Builtin::BI__builtin_memcmp:
4438	case Builtin::BImemcmp:
4439	return Builtin::BImemcmp;
4440
4441	case Builtin::BI__builtin_bcmp:
4442	case Builtin::BIbcmp:
4443	return Builtin::BIbcmp;
4444
4445	case Builtin::BI__builtin_strncpy:
4446	case Builtin::BI__builtin___strncpy_chk:
4447	case Builtin::BIstrncpy:
4448	return Builtin::BIstrncpy;
4449
4450	case Builtin::BI__builtin_strncmp:
4451	case Builtin::BIstrncmp:
4452	return Builtin::BIstrncmp;
4453
4454	case Builtin::BI__builtin_strncasecmp:
4455	case Builtin::BIstrncasecmp:
4456	return Builtin::BIstrncasecmp;
4457
4458	case Builtin::BI__builtin_strncat:
4459	case Builtin::BI__builtin___strncat_chk:
4460	case Builtin::BIstrncat:
4461	return Builtin::BIstrncat;
4462
4463	case Builtin::BI__builtin_strndup:
4464	case Builtin::BIstrndup:
4465	return Builtin::BIstrndup;
4466
4467	case Builtin::BI__builtin_strlen:
4468	case Builtin::BIstrlen:
4469	return Builtin::BIstrlen;
4470
4471	case Builtin::BI__builtin_bzero:
4472	case Builtin::BIbzero:
4473	return Builtin::BIbzero;
4474
4475	case Builtin::BI__builtin_bcopy:
4476	case Builtin::BIbcopy:
4477	return Builtin::BIbcopy;
4478
4479	case Builtin::BIfree:
4480	return Builtin::BIfree;
4481
4482	default:
4483	if (isExternC()) {
4484	if (FnInfo->isStr("memset"))
4485	return Builtin::BImemset;
4486	if (FnInfo->isStr("memcpy"))
4487	return Builtin::BImemcpy;
4488	if (FnInfo->isStr("mempcpy"))
4489	return Builtin::BImempcpy;
4490	if (FnInfo->isStr("memmove"))
4491	return Builtin::BImemmove;
4492	if (FnInfo->isStr("memcmp"))
4493	return Builtin::BImemcmp;
4494	if (FnInfo->isStr("bcmp"))
4495	return Builtin::BIbcmp;
4496	if (FnInfo->isStr("strncpy"))
4497	return Builtin::BIstrncpy;
4498	if (FnInfo->isStr("strncmp"))
4499	return Builtin::BIstrncmp;
4500	if (FnInfo->isStr("strncasecmp"))
4501	return Builtin::BIstrncasecmp;
4502	if (FnInfo->isStr("strncat"))
4503	return Builtin::BIstrncat;
4504	if (FnInfo->isStr("strndup"))
4505	return Builtin::BIstrndup;
4506	if (FnInfo->isStr("strlen"))
4507	return Builtin::BIstrlen;
4508	if (FnInfo->isStr("bzero"))
4509	return Builtin::BIbzero;
4510	if (FnInfo->isStr("bcopy"))
4511	return Builtin::BIbcopy;
4512	} else if (isInStdNamespace()) {
4513	if (FnInfo->isStr("free"))
4514	return Builtin::BIfree;
4515	}
4516	break;
4517	}
4518	return 0;
4519	}
4520
4521	unsigned FunctionDecl::getODRHash() const {
4522	assert(hasODRHash());
4523	return ODRHash;
4524	}
4525
4526	unsigned FunctionDecl::getODRHash() {
4527	if (hasODRHash())
4528	return ODRHash;
4529
4530	if (auto *FT = getInstantiatedFromMemberFunction()) {
4531	setHasODRHash(true);
4532	ODRHash = FT->getODRHash();
4533	return ODRHash;
4534	}
4535
4536	class ODRHash Hash;
4537	Hash.AddFunctionDecl(Function: this);
4538	setHasODRHash(true);
4539	ODRHash = Hash.CalculateHash();
4540	return ODRHash;
4541	}
4542
4543	//===----------------------------------------------------------------------===//
4544	// FieldDecl Implementation
4545	//===----------------------------------------------------------------------===//
4546
4547	FieldDecl *FieldDecl::Create(const ASTContext &C, DeclContext *DC,
4548	SourceLocation StartLoc, SourceLocation IdLoc,
4549	const IdentifierInfo *Id, QualType T,
4550	TypeSourceInfo *TInfo, Expr *BW, bool Mutable,
4551	InClassInitStyle InitStyle) {
4552	return new (C, DC) FieldDecl(Decl::Field, DC, StartLoc, IdLoc, Id, T, TInfo,
4553	BW, Mutable, InitStyle);
4554	}
4555
4556	FieldDecl *FieldDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
4557	return new (C, ID) FieldDecl(Field, nullptr, SourceLocation(),
4558	SourceLocation(), nullptr, QualType(), nullptr,
4559	nullptr, false, ICIS_NoInit);
4560	}
4561
4562	bool FieldDecl::isAnonymousStructOrUnion() const {
4563	if (!isImplicit() || getDeclName())
4564	return false;
4565
4566	if (const auto *Record = getType()->getAs<RecordType>())
4567	return Record->getDecl()->isAnonymousStructOrUnion();
4568
4569	return false;
4570	}
4571
4572	Expr *FieldDecl::getInClassInitializer() const {
4573	if (!hasInClassInitializer())
4574	return nullptr;
4575
4576	LazyDeclStmtPtr InitPtr = BitField ? InitAndBitWidth->Init : Init;
4577	return cast_if_present<Expr>(
4578	InitPtr.isOffset() ? InitPtr.get(Source: getASTContext().getExternalSource())
4579	: InitPtr.get(Source: nullptr));
4580	}
4581
4582	void FieldDecl::setInClassInitializer(Expr *NewInit) {
4583	setLazyInClassInitializer(LazyDeclStmtPtr(NewInit));
4584	}
4585
4586	void FieldDecl::setLazyInClassInitializer(LazyDeclStmtPtr NewInit) {
4587	assert(hasInClassInitializer() && !getInClassInitializer());
4588	if (BitField)
4589	InitAndBitWidth->Init = NewInit;
4590	else
4591	Init = NewInit;
4592	}
4593
4594	unsigned FieldDecl::getBitWidthValue(const ASTContext &Ctx) const {
4595	assert(isBitField() && "not a bitfield");
4596	return getBitWidth()->EvaluateKnownConstInt(Ctx).getZExtValue();
4597	}
4598
4599	bool FieldDecl::isZeroLengthBitField(const ASTContext &Ctx) const {
4600	return isUnnamedBitField() && !getBitWidth()->isValueDependent() &&
4601	getBitWidthValue(Ctx) == 0;
4602	}
4603
4604	bool FieldDecl::isZeroSize(const ASTContext &Ctx) const {
4605	if (isZeroLengthBitField(Ctx))
4606	return true;
4607
4608	// C++2a [intro.object]p7:
4609	// An object has nonzero size if it
4610	// -- is not a potentially-overlapping subobject, or
4611	if (!hasAttr<NoUniqueAddressAttr>())
4612	return false;
4613
4614	// -- is not of class type, or
4615	const auto *RT = getType()->getAs<RecordType>();
4616	if (!RT)
4617	return false;
4618	const RecordDecl *RD = RT->getDecl()->getDefinition();
4619	if (!RD) {
4620	assert(isInvalidDecl() && "valid field has incomplete type");
4621	return false;
4622	}
4623
4624	// -- [has] virtual member functions or virtual base classes, or
4625	// -- has subobjects of nonzero size or bit-fields of nonzero length
4626	const auto *CXXRD = cast<CXXRecordDecl>(Val: RD);
4627	if (!CXXRD->isEmpty())
4628	return false;
4629
4630	// Otherwise, [...] the circumstances under which the object has zero size
4631	// are implementation-defined.
4632	if (!Ctx.getTargetInfo().getCXXABI().isMicrosoft())
4633	return true;
4634
4635	// MS ABI: has nonzero size if it is a class type with class type fields,
4636	// whether or not they have nonzero size
4637	return !llvm::any_of(CXXRD->fields(), [](const FieldDecl *Field) {
4638	return Field->getType()->getAs<RecordType>();
4639	});
4640	}
4641
4642	bool FieldDecl::isPotentiallyOverlapping() const {
4643	return hasAttr<NoUniqueAddressAttr>() && getType()->getAsCXXRecordDecl();
4644	}
4645
4646	unsigned FieldDecl::getFieldIndex() const {
4647	const FieldDecl *Canonical = getCanonicalDecl();
4648	if (Canonical != this)
4649	return Canonical->getFieldIndex();
4650
4651	if (CachedFieldIndex) return CachedFieldIndex - 1;
4652
4653	unsigned Index = 0;
4654	const RecordDecl *RD = getParent()->getDefinition();
4655	assert(RD && "requested index for field of struct with no definition");
4656
4657	for (auto *Field : RD->fields()) {
4658	Field->getCanonicalDecl()->CachedFieldIndex = Index + 1;
4659	assert(Field->getCanonicalDecl()->CachedFieldIndex == Index + 1 &&
4660	"overflow in field numbering");
4661	++Index;
4662	}
4663
4664	assert(CachedFieldIndex && "failed to find field in parent");
4665	return CachedFieldIndex - 1;
4666	}
4667
4668	SourceRange FieldDecl::getSourceRange() const {
4669	const Expr *FinalExpr = getInClassInitializer();
4670	if (!FinalExpr)
4671	FinalExpr = getBitWidth();
4672	if (FinalExpr)
4673	return SourceRange(getInnerLocStart(), FinalExpr->getEndLoc());
4674	return DeclaratorDecl::getSourceRange();
4675	}
4676
4677	void FieldDecl::setCapturedVLAType(const VariableArrayType *VLAType) {
4678	assert((getParent()->isLambda() || getParent()->isCapturedRecord()) &&
4679	"capturing type in non-lambda or captured record.");
4680	assert(StorageKind == ISK_NoInit && !BitField &&
4681	"bit-field or field with default member initializer cannot capture "
4682	"VLA type");
4683	StorageKind = ISK_CapturedVLAType;
4684	CapturedVLAType = VLAType;
4685	}
4686
4687	void FieldDecl::printName(raw_ostream &OS, const PrintingPolicy &Policy) const {
4688	// Print unnamed members using name of their type.
4689	if (isAnonymousStructOrUnion()) {
4690	this->getType().print(OS, Policy);
4691	return;
4692	}
4693	// Otherwise, do the normal printing.
4694	DeclaratorDecl::printName(OS, Policy);
4695	}
4696
4697	//===----------------------------------------------------------------------===//
4698	// TagDecl Implementation
4699	//===----------------------------------------------------------------------===//
4700
4701	TagDecl::TagDecl(Kind DK, TagKind TK, const ASTContext &C, DeclContext *DC,
4702	SourceLocation L, IdentifierInfo *Id, TagDecl *PrevDecl,
4703	SourceLocation StartL)
4704	: TypeDecl(DK, DC, L, Id, StartL), DeclContext(DK), redeclarable_base(C),
4705	TypedefNameDeclOrQualifier((TypedefNameDecl *)nullptr) {
4706	assert((DK != Enum || TK == TagTypeKind::Enum) &&
4707	"EnumDecl not matched with TagTypeKind::Enum");
4708	setPreviousDecl(PrevDecl);
4709	setTagKind(TK);
4710	setCompleteDefinition(false);
4711	setBeingDefined(false);
4712	setEmbeddedInDeclarator(false);
4713	setFreeStanding(false);
4714	setCompleteDefinitionRequired(false);
4715	TagDeclBits.IsThisDeclarationADemotedDefinition = false;
4716	}
4717
4718	SourceLocation TagDecl::getOuterLocStart() const {
4719	return getTemplateOrInnerLocStart(decl: this);
4720	}
4721
4722	SourceRange TagDecl::getSourceRange() const {
4723	SourceLocation RBraceLoc = BraceRange.getEnd();
4724	SourceLocation E = RBraceLoc.isValid() ? RBraceLoc : getLocation();
4725	return SourceRange(getOuterLocStart(), E);
4726	}
4727
4728	TagDecl *TagDecl::getCanonicalDecl() { return getFirstDecl(); }
4729
4730	void TagDecl::setTypedefNameForAnonDecl(TypedefNameDecl *TDD) {
4731	TypedefNameDeclOrQualifier = TDD;
4732	if (const Type *T = getTypeForDecl()) {
4733	(void)T;
4734	assert(T->isLinkageValid());
4735	}
4736	assert(isLinkageValid());
4737	}
4738
4739	void TagDecl::startDefinition() {
4740	setBeingDefined(true);
4741
4742	if (auto *D = dyn_cast<CXXRecordDecl>(Val: this)) {
4743	struct CXXRecordDecl::DefinitionData *Data =
4744	new (getASTContext()) struct CXXRecordDecl::DefinitionData(D);
4745	for (auto *I : redecls())
4746	cast<CXXRecordDecl>(I)->DefinitionData = Data;
4747	}
4748	}
4749
4750	void TagDecl::completeDefinition() {
4751	assert((!isa<CXXRecordDecl>(this) ||
4752	cast<CXXRecordDecl>(this)->hasDefinition()) &&
4753	"definition completed but not started");
4754
4755	setCompleteDefinition(true);
4756	setBeingDefined(false);
4757
4758	if (ASTMutationListener *L = getASTMutationListener())
4759	L->CompletedTagDefinition(D: this);
4760	}
4761
4762	TagDecl *TagDecl::getDefinition() const {
4763	if (isCompleteDefinition())
4764	return const_cast<TagDecl *>(this);
4765
4766	// If it's possible for us to have an out-of-date definition, check now.
4767	if (mayHaveOutOfDateDef()) {
4768	if (IdentifierInfo *II = getIdentifier()) {
4769	if (II->isOutOfDate()) {
4770	updateOutOfDate(*II);
4771	}
4772	}
4773	}
4774
4775	if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(Val: this))
4776	return CXXRD->getDefinition();
4777
4778	for (auto *R : redecls())
4779	if (R->isCompleteDefinition())
4780	return R;
4781
4782	return nullptr;
4783	}
4784
4785	void TagDecl::setQualifierInfo(NestedNameSpecifierLoc QualifierLoc) {
4786	if (QualifierLoc) {
4787	// Make sure the extended qualifier info is allocated.
4788	if (!hasExtInfo())
4789	TypedefNameDeclOrQualifier = new (getASTContext()) ExtInfo;
4790	// Set qualifier info.
4791	getExtInfo()->QualifierLoc = QualifierLoc;
4792	} else {
4793	// Here Qualifier == 0, i.e., we are removing the qualifier (if any).
4794	if (hasExtInfo()) {
4795	if (getExtInfo()->NumTemplParamLists == 0) {
4796	getASTContext().Deallocate(getExtInfo());
4797	TypedefNameDeclOrQualifier = (TypedefNameDecl *)nullptr;
4798	}
4799	else
4800	getExtInfo()->QualifierLoc = QualifierLoc;
4801	}
4802	}
4803	}
4804
4805	void TagDecl::printName(raw_ostream &OS, const PrintingPolicy &Policy) const {
4806	DeclarationName Name = getDeclName();
4807	// If the name is supposed to have an identifier but does not have one, then
4808	// the tag is anonymous and we should print it differently.
4809	if (Name.isIdentifier() && !Name.getAsIdentifierInfo()) {
4810	// If the caller wanted to print a qualified name, they've already printed
4811	// the scope. And if the caller doesn't want that, the scope information
4812	// is already printed as part of the type.
4813	PrintingPolicy Copy(Policy);
4814	Copy.SuppressScope = true;
4815	getASTContext().getTagDeclType(this).print(OS, Copy);
4816	return;
4817	}
4818	// Otherwise, do the normal printing.
4819	Name.print(OS, Policy);
4820	}
4821
4822	void TagDecl::setTemplateParameterListsInfo(
4823	ASTContext &Context, ArrayRef<TemplateParameterList *> TPLists) {
4824	assert(!TPLists.empty());
4825	// Make sure the extended decl info is allocated.
4826	if (!hasExtInfo())
4827	// Allocate external info struct.
4828	TypedefNameDeclOrQualifier = new (getASTContext()) ExtInfo;
4829	// Set the template parameter lists info.
4830	getExtInfo()->setTemplateParameterListsInfo(Context, TPLists);
4831	}
4832
4833	//===----------------------------------------------------------------------===//
4834	// EnumDecl Implementation
4835	//===----------------------------------------------------------------------===//
4836
4837	EnumDecl::EnumDecl(ASTContext &C, DeclContext *DC, SourceLocation StartLoc,
4838	SourceLocation IdLoc, IdentifierInfo *Id, EnumDecl *PrevDecl,
4839	bool Scoped, bool ScopedUsingClassTag, bool Fixed)
4840	: TagDecl(Enum, TagTypeKind::Enum, C, DC, IdLoc, Id, PrevDecl, StartLoc) {
4841	assert(Scoped || !ScopedUsingClassTag);
4842	IntegerType = nullptr;
4843	setNumPositiveBits(0);
4844	setNumNegativeBits(0);
4845	setScoped(Scoped);
4846	setScopedUsingClassTag(ScopedUsingClassTag);
4847	setFixed(Fixed);
4848	setHasODRHash(false);
4849	ODRHash = 0;
4850	}
4851
4852	void EnumDecl::anchor() {}
4853
4854	EnumDecl *EnumDecl::Create(ASTContext &C, DeclContext *DC,
4855	SourceLocation StartLoc, SourceLocation IdLoc,
4856	IdentifierInfo *Id,
4857	EnumDecl *PrevDecl, bool IsScoped,
4858	bool IsScopedUsingClassTag, bool IsFixed) {
4859	auto *Enum = new (C, DC) EnumDecl(C, DC, StartLoc, IdLoc, Id, PrevDecl,
4860	IsScoped, IsScopedUsingClassTag, IsFixed);
4861	Enum->setMayHaveOutOfDateDef(C.getLangOpts().Modules);
4862	C.getTypeDeclType(Enum, PrevDecl);
4863	return Enum;
4864	}
4865
4866	EnumDecl *EnumDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
4867	EnumDecl *Enum =
4868	new (C, ID) EnumDecl(C, nullptr, SourceLocation(), SourceLocation(),
4869	nullptr, nullptr, false, false, false);
4870	Enum->setMayHaveOutOfDateDef(C.getLangOpts().Modules);
4871	return Enum;
4872	}
4873
4874	SourceRange EnumDecl::getIntegerTypeRange() const {
4875	if (const TypeSourceInfo *TI = getIntegerTypeSourceInfo())
4876	return TI->getTypeLoc().getSourceRange();
4877	return SourceRange();
4878	}
4879
4880	void EnumDecl::completeDefinition(QualType NewType,
4881	QualType NewPromotionType,
4882	unsigned NumPositiveBits,
4883	unsigned NumNegativeBits) {
4884	assert(!isCompleteDefinition() && "Cannot redefine enums!");
4885	if (!IntegerType)
4886	IntegerType = NewType.getTypePtr();
4887	PromotionType = NewPromotionType;
4888	setNumPositiveBits(NumPositiveBits);
4889	setNumNegativeBits(NumNegativeBits);
4890	TagDecl::completeDefinition();
4891	}
4892
4893	bool EnumDecl::isClosed() const {
4894	if (const auto *A = getAttr<EnumExtensibilityAttr>())
4895	return A->getExtensibility() == EnumExtensibilityAttr::Closed;
4896	return true;
4897	}
4898
4899	bool EnumDecl::isClosedFlag() const {
4900	return isClosed() && hasAttr<FlagEnumAttr>();
4901	}
4902
4903	bool EnumDecl::isClosedNonFlag() const {
4904	return isClosed() && !hasAttr<FlagEnumAttr>();
4905	}
4906
4907	TemplateSpecializationKind EnumDecl::getTemplateSpecializationKind() const {
4908	if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
4909	return MSI->getTemplateSpecializationKind();
4910
4911	return TSK_Undeclared;
4912	}
4913
4914	void EnumDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
4915	SourceLocation PointOfInstantiation) {
4916	MemberSpecializationInfo *MSI = getMemberSpecializationInfo();
4917	assert(MSI && "Not an instantiated member enumeration?");
4918	MSI->setTemplateSpecializationKind(TSK);
4919	if (TSK != TSK_ExplicitSpecialization &&
4920	PointOfInstantiation.isValid() &&
4921	MSI->getPointOfInstantiation().isInvalid())
4922	MSI->setPointOfInstantiation(PointOfInstantiation);
4923	}
4924
4925	EnumDecl *EnumDecl::getTemplateInstantiationPattern() const {
4926	if (MemberSpecializationInfo *MSInfo = getMemberSpecializationInfo()) {
4927	if (isTemplateInstantiation(Kind: MSInfo->getTemplateSpecializationKind())) {
4928	EnumDecl *ED = getInstantiatedFromMemberEnum();
4929	while (auto *NewED = ED->getInstantiatedFromMemberEnum())
4930	ED = NewED;
4931	return getDefinitionOrSelf(D: ED);
4932	}
4933	}
4934
4935	assert(!isTemplateInstantiation(getTemplateSpecializationKind()) &&
4936	"couldn't find pattern for enum instantiation");
4937	return nullptr;
4938	}
4939
4940	EnumDecl *EnumDecl::getInstantiatedFromMemberEnum() const {
4941	if (SpecializationInfo)
4942	return cast<EnumDecl>(Val: SpecializationInfo->getInstantiatedFrom());
4943
4944	return nullptr;
4945	}
4946
4947	void EnumDecl::setInstantiationOfMemberEnum(ASTContext &C, EnumDecl *ED,
4948	TemplateSpecializationKind TSK) {
4949	assert(!SpecializationInfo && "Member enum is already a specialization");
4950	SpecializationInfo = new (C) MemberSpecializationInfo(ED, TSK);
4951	}
4952
4953	unsigned EnumDecl::getODRHash() {
4954	if (hasODRHash())
4955	return ODRHash;
4956
4957	class ODRHash Hash;
4958	Hash.AddEnumDecl(Enum: this);
4959	setHasODRHash(true);
4960	ODRHash = Hash.CalculateHash();
4961	return ODRHash;
4962	}
4963
4964	SourceRange EnumDecl::getSourceRange() const {
4965	auto Res = TagDecl::getSourceRange();
4966	// Set end-point to enum-base, e.g. enum foo : ^bar
4967	if (auto *TSI = getIntegerTypeSourceInfo()) {
4968	// TagDecl doesn't know about the enum base.
4969	if (!getBraceRange().getEnd().isValid())
4970	Res.setEnd(TSI->getTypeLoc().getEndLoc());
4971	}
4972	return Res;
4973	}
4974
4975	void EnumDecl::getValueRange(llvm::APInt &Max, llvm::APInt &Min) const {
4976	unsigned Bitwidth = getASTContext().getIntWidth(getIntegerType());
4977	unsigned NumNegativeBits = getNumNegativeBits();
4978	unsigned NumPositiveBits = getNumPositiveBits();
4979
4980	if (NumNegativeBits) {
4981	unsigned NumBits = std::max(a: NumNegativeBits, b: NumPositiveBits + 1);
4982	Max = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
4983	Min = -Max;
4984	} else {
4985	Max = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
4986	Min = llvm::APInt::getZero(numBits: Bitwidth);
4987	}
4988	}
4989
4990	//===----------------------------------------------------------------------===//
4991	// RecordDecl Implementation
4992	//===----------------------------------------------------------------------===//
4993
4994	RecordDecl::RecordDecl(Kind DK, TagKind TK, const ASTContext &C,
4995	DeclContext *DC, SourceLocation StartLoc,
4996	SourceLocation IdLoc, IdentifierInfo *Id,
4997	RecordDecl *PrevDecl)
4998	: TagDecl(DK, TK, C, DC, IdLoc, Id, PrevDecl, StartLoc) {
4999	assert(classof(static_cast<Decl *>(this)) && "Invalid Kind!");
5000	setHasFlexibleArrayMember(false);
5001	setAnonymousStructOrUnion(false);
5002	setHasObjectMember(false);
5003	setHasVolatileMember(false);
5004	setHasLoadedFieldsFromExternalStorage(false);
5005	setNonTrivialToPrimitiveDefaultInitialize(false);
5006	setNonTrivialToPrimitiveCopy(false);
5007	setNonTrivialToPrimitiveDestroy(false);
5008	setHasNonTrivialToPrimitiveDefaultInitializeCUnion(false);
5009	setHasNonTrivialToPrimitiveDestructCUnion(false);
5010	setHasNonTrivialToPrimitiveCopyCUnion(false);
5011	setParamDestroyedInCallee(false);
5012	setArgPassingRestrictions(RecordArgPassingKind::CanPassInRegs);
5013	setIsRandomized(false);
5014	setODRHash(0);
5015	}
5016
5017	RecordDecl *RecordDecl::Create(const ASTContext &C, TagKind TK, DeclContext *DC,
5018	SourceLocation StartLoc, SourceLocation IdLoc,
5019	IdentifierInfo *Id, RecordDecl* PrevDecl) {
5020	RecordDecl *R = new (C, DC) RecordDecl(Record, TK, C, DC,
5021	StartLoc, IdLoc, Id, PrevDecl);
5022	R->setMayHaveOutOfDateDef(C.getLangOpts().Modules);
5023
5024	C.getTypeDeclType(R, PrevDecl);
5025	return R;
5026	}
5027
5028	RecordDecl *RecordDecl::CreateDeserialized(const ASTContext &C, Decl::DeclID ID) {
5029	RecordDecl *R = new (C, ID)
5030	RecordDecl(Record, TagTypeKind::Struct, C, nullptr, SourceLocation(),
5031	SourceLocation(), nullptr, nullptr);
5032	R->setMayHaveOutOfDateDef(C.getLangOpts().Modules);
5033	return R;
5034	}
5035
5036	bool RecordDecl::isInjectedClassName() const {
5037	return isImplicit() && getDeclName() && getDeclContext()->isRecord() &&
5038	cast<RecordDecl>(getDeclContext())->getDeclName() == getDeclName();
5039	}
5040
5041	bool RecordDecl::isLambda() const {
5042	if (auto RD = dyn_cast<CXXRecordDecl>(Val: this))
5043	return RD->isLambda();
5044	return false;
5045	}
5046
5047	bool RecordDecl::isCapturedRecord() const {
5048	return hasAttr<CapturedRecordAttr>();
5049	}
5050
5051	void RecordDecl::setCapturedRecord() {
5052	addAttr(CapturedRecordAttr::CreateImplicit(getASTContext()));
5053	}
5054
5055	bool RecordDecl::isOrContainsUnion() const {
5056	if (isUnion())
5057	return true;
5058
5059	if (const RecordDecl *Def = getDefinition()) {
5060	for (const FieldDecl *FD : Def->fields()) {
5061	const RecordType *RT = FD->getType()->getAs<RecordType>();
5062	if (RT && RT->getDecl()->isOrContainsUnion())
5063	return true;
5064	}
5065	}
5066
5067	return false;
5068	}
5069
5070	RecordDecl::field_iterator RecordDecl::field_begin() const {
5071	if (hasExternalLexicalStorage() && !hasLoadedFieldsFromExternalStorage())
5072	LoadFieldsFromExternalStorage();
5073	// This is necessary for correctness for C++ with modules.
5074	// FIXME: Come up with a test case that breaks without definition.
5075	if (RecordDecl *D = getDefinition(); D && D != this)
5076	return D->field_begin();
5077	return field_iterator(decl_iterator(FirstDecl));
5078	}
5079
5080	/// completeDefinition - Notes that the definition of this type is now
5081	/// complete.
5082	void RecordDecl::completeDefinition() {
5083	assert(!isCompleteDefinition() && "Cannot redefine record!");
5084	TagDecl::completeDefinition();
5085
5086	ASTContext &Ctx = getASTContext();
5087
5088	// Layouts are dumped when computed, so if we are dumping for all complete
5089	// types, we need to force usage to get types that wouldn't be used elsewhere.
5090	//
5091	// If the type is dependent, then we can't compute its layout because there
5092	// is no way for us to know the size or alignment of a dependent type. Also
5093	// ignore declarations marked as invalid since 'getASTRecordLayout()' asserts
5094	// on that.
5095	if (Ctx.getLangOpts().DumpRecordLayoutsComplete && !isDependentType() &&
5096	!isInvalidDecl())
5097	(void)Ctx.getASTRecordLayout(D: this);
5098	}
5099
5100	/// isMsStruct - Get whether or not this record uses ms_struct layout.
5101	/// This which can be turned on with an attribute, pragma, or the
5102	/// -mms-bitfields command-line option.
5103	bool RecordDecl::isMsStruct(const ASTContext &C) const {
5104	return hasAttr<MSStructAttr>() || C.getLangOpts().MSBitfields == 1;
5105	}
5106
5107	void RecordDecl::reorderDecls(const SmallVectorImpl<Decl *> &Decls) {
5108	std::tie(args&: FirstDecl, args&: LastDecl) = DeclContext::BuildDeclChain(Decls, FieldsAlreadyLoaded: false);
5109	LastDecl->NextInContextAndBits.setPointer(nullptr);
5110	setIsRandomized(true);
5111	}
5112
5113	void RecordDecl::LoadFieldsFromExternalStorage() const {
5114	ExternalASTSource *Source = getASTContext().getExternalSource();
5115	assert(hasExternalLexicalStorage() && Source && "No external storage?");
5116
5117	// Notify that we have a RecordDecl doing some initialization.
5118	ExternalASTSource::Deserializing TheFields(Source);
5119
5120	SmallVector<Decl*, 64> Decls;
5121	setHasLoadedFieldsFromExternalStorage(true);
5122	Source->FindExternalLexicalDecls(this, [](Decl::Kind K) {
5123	return FieldDecl::classofKind(K) || IndirectFieldDecl::classofKind(K);
5124	}, Decls);
5125
5126	#ifndef NDEBUG
5127	// Check that all decls we got were FieldDecls.
5128	for (unsigned i=0, e=Decls.size(); i != e; ++i)
5129	assert(isa<FieldDecl>(Decls[i]) || isa<IndirectFieldDecl>(Decls[i]));
5130	#endif
5131
5132	if (Decls.empty())
5133	return;
5134
5135	auto [ExternalFirst, ExternalLast] =
5136	BuildDeclChain(Decls,
5137	/*FieldsAlreadyLoaded=*/false);
5138	ExternalLast->NextInContextAndBits.setPointer(FirstDecl);
5139	FirstDecl = ExternalFirst;
5140	if (!LastDecl)
5141	LastDecl = ExternalLast;
5142	}
5143
5144	bool RecordDecl::mayInsertExtraPadding(bool EmitRemark) const {
5145	ASTContext &Context = getASTContext();
5146	const SanitizerMask EnabledAsanMask = Context.getLangOpts().Sanitize.Mask &
5147	(SanitizerKind::Address | SanitizerKind::KernelAddress);
5148	if (!EnabledAsanMask || !Context.getLangOpts().SanitizeAddressFieldPadding)
5149	return false;
5150	const auto &NoSanitizeList = Context.getNoSanitizeList();
5151	const auto *CXXRD = dyn_cast<CXXRecordDecl>(Val: this);
5152	// We may be able to relax some of these requirements.
5153	int ReasonToReject = -1;
5154	if (!CXXRD || CXXRD->isExternCContext())
5155	ReasonToReject = 0; // is not C++.
5156	else if (CXXRD->hasAttr<PackedAttr>())
5157	ReasonToReject = 1; // is packed.
5158	else if (CXXRD->isUnion())
5159	ReasonToReject = 2; // is a union.
5160	else if (CXXRD->isTriviallyCopyable())
5161	ReasonToReject = 3; // is trivially copyable.
5162	else if (CXXRD->hasTrivialDestructor())
5163	ReasonToReject = 4; // has trivial destructor.
5164	else if (CXXRD->isStandardLayout())
5165	ReasonToReject = 5; // is standard layout.
5166	else if (NoSanitizeList.containsLocation(EnabledAsanMask, getLocation(),
5167	"field-padding"))
5168	ReasonToReject = 6; // is in an excluded file.
5169	else if (NoSanitizeList.containsType(
5170	EnabledAsanMask, getQualifiedNameAsString(), "field-padding"))
5171	ReasonToReject = 7; // The type is excluded.
5172
5173	if (EmitRemark) {
5174	if (ReasonToReject >= 0)
5175	Context.getDiagnostics().Report(
5176	getLocation(),
5177	diag::remark_sanitize_address_insert_extra_padding_rejected)
5178	<< getQualifiedNameAsString() << ReasonToReject;
5179	else
5180	Context.getDiagnostics().Report(
5181	getLocation(),
5182	diag::remark_sanitize_address_insert_extra_padding_accepted)
5183	<< getQualifiedNameAsString();
5184	}
5185	return ReasonToReject < 0;
5186	}
5187
5188	const FieldDecl *RecordDecl::findFirstNamedDataMember() const {
5189	for (const auto *I : fields()) {
5190	if (I->getIdentifier())
5191	return I;
5192
5193	if (const auto *RT = I->getType()->getAs<RecordType>())
5194	if (const FieldDecl *NamedDataMember =
5195	RT->getDecl()->findFirstNamedDataMember())
5196	return NamedDataMember;
5197	}
5198
5199	// We didn't find a named data member.
5200	return nullptr;
5201	}
5202
5203	unsigned RecordDecl::getODRHash() {
5204	if (hasODRHash())
5205	return RecordDeclBits.ODRHash;
5206
5207	// Only calculate hash on first call of getODRHash per record.
5208	ODRHash Hash;
5209	Hash.AddRecordDecl(Record: this);
5210	// For RecordDecl the ODRHash is stored in the remaining 26
5211	// bit of RecordDeclBits, adjust the hash to accomodate.
5212	setODRHash(Hash.CalculateHash() >> 6);
5213	return RecordDeclBits.ODRHash;
5214	}
5215
5216	//===----------------------------------------------------------------------===//
5217	// BlockDecl Implementation
5218	//===----------------------------------------------------------------------===//
5219
5220	BlockDecl::BlockDecl(DeclContext *DC, SourceLocation CaretLoc)
5221	: Decl(Block, DC, CaretLoc), DeclContext(Block) {
5222	setIsVariadic(false);
5223	setCapturesCXXThis(false);
5224	setBlockMissingReturnType(true);
5225	setIsConversionFromLambda(false);
5226	setDoesNotEscape(false);
5227	setCanAvoidCopyToHeap(false);
5228	}
5229
5230	void BlockDecl::setParams(ArrayRef<ParmVarDecl *> NewParamInfo) {
5231	assert(!ParamInfo && "Already has param info!");
5232
5233	// Zero params -> null pointer.
5234	if (!NewParamInfo.empty()) {
5235	NumParams = NewParamInfo.size();
5236	ParamInfo = new (getASTContext()) ParmVarDecl*[NewParamInfo.size()];
5237	std::copy(first: NewParamInfo.begin(), last: NewParamInfo.end(), result: ParamInfo);
5238	}
5239	}
5240
5241	void BlockDecl::setCaptures(ASTContext &Context, ArrayRef<Capture> Captures,
5242	bool CapturesCXXThis) {
5243	this->setCapturesCXXThis(CapturesCXXThis);
5244	this->NumCaptures = Captures.size();
5245
5246	if (Captures.empty()) {
5247	this->Captures = nullptr;
5248	return;
5249	}
5250
5251	this->Captures = Captures.copy(A&: Context).data();
5252	}
5253
5254	bool BlockDecl::capturesVariable(const VarDecl *variable) const {
5255	for (const auto &I : captures())
5256	// Only auto vars can be captured, so no redeclaration worries.
5257	if (I.getVariable() == variable)
5258	return true;
5259
5260	return false;
5261	}
5262
5263	SourceRange BlockDecl::getSourceRange() const {
5264	return SourceRange(getLocation(), Body ? Body->getEndLoc() : getLocation());
5265	}
5266
5267	//===----------------------------------------------------------------------===//
5268	// Other Decl Allocation/Deallocation Method Implementations
5269	//===----------------------------------------------------------------------===//
5270
5271	void TranslationUnitDecl::anchor() {}
5272
5273	TranslationUnitDecl *TranslationUnitDecl::Create(ASTContext &C) {
5274	return new (C, (DeclContext *)nullptr) TranslationUnitDecl(C);
5275	}
5276
5277	void TranslationUnitDecl::setAnonymousNamespace(NamespaceDecl *D) {
5278	AnonymousNamespace = D;
5279
5280	if (ASTMutationListener *Listener = Ctx.getASTMutationListener())
5281	Listener->AddedAnonymousNamespace(TU: this, AnonNamespace: D);
5282	}
5283
5284	void PragmaCommentDecl::anchor() {}
5285
5286	PragmaCommentDecl *PragmaCommentDecl::Create(const ASTContext &C,
5287	TranslationUnitDecl *DC,
5288	SourceLocation CommentLoc,
5289	PragmaMSCommentKind CommentKind,
5290	StringRef Arg) {
5291	PragmaCommentDecl *PCD =
5292	new (C, DC, additionalSizeToAlloc<char>(Arg.size() + 1))
5293	PragmaCommentDecl(DC, CommentLoc, CommentKind);
5294	memcpy(PCD->getTrailingObjects<char>(), Arg.data(), Arg.size());
5295	PCD->getTrailingObjects<char>()[Arg.size()] = '\0';
5296	return PCD;
5297	}
5298
5299	PragmaCommentDecl *PragmaCommentDecl::CreateDeserialized(ASTContext &C,
5300	Decl::DeclID ID,
5301	unsigned ArgSize) {
5302	return new (C, ID, additionalSizeToAlloc<char>(Counts: ArgSize + 1))
5303	PragmaCommentDecl(nullptr, SourceLocation(), PCK_Unknown);
5304	}
5305
5306	void PragmaDetectMismatchDecl::anchor() {}
5307
5308	PragmaDetectMismatchDecl *
5309	PragmaDetectMismatchDecl::Create(const ASTContext &C, TranslationUnitDecl *DC,
5310	SourceLocation Loc, StringRef Name,
5311	StringRef Value) {
5312	size_t ValueStart = Name.size() + 1;
5313	PragmaDetectMismatchDecl *PDMD =
5314	new (C, DC, additionalSizeToAlloc<char>(ValueStart + Value.size() + 1))
5315	PragmaDetectMismatchDecl(DC, Loc, ValueStart);
5316	memcpy(PDMD->getTrailingObjects<char>(), Name.data(), Name.size());
5317	PDMD->getTrailingObjects<char>()[Name.size()] = '\0';
5318	memcpy(PDMD->getTrailingObjects<char>() + ValueStart, Value.data(),
5319	Value.size());
5320	PDMD->getTrailingObjects<char>()[ValueStart + Value.size()] = '\0';
5321	return PDMD;
5322	}
5323
5324	PragmaDetectMismatchDecl *
5325	PragmaDetectMismatchDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID,
5326	unsigned NameValueSize) {
5327	return new (C, ID, additionalSizeToAlloc<char>(Counts: NameValueSize + 1))
5328	PragmaDetectMismatchDecl(nullptr, SourceLocation(), 0);
5329	}
5330
5331	void ExternCContextDecl::anchor() {}
5332
5333	ExternCContextDecl *ExternCContextDecl::Create(const ASTContext &C,
5334	TranslationUnitDecl *DC) {
5335	return new (C, DC) ExternCContextDecl(DC);
5336	}
5337
5338	void LabelDecl::anchor() {}
5339
5340	LabelDecl *LabelDecl::Create(ASTContext &C, DeclContext *DC,
5341	SourceLocation IdentL, IdentifierInfo *II) {
5342	return new (C, DC) LabelDecl(DC, IdentL, II, nullptr, IdentL);
5343	}
5344
5345	LabelDecl *LabelDecl::Create(ASTContext &C, DeclContext *DC,
5346	SourceLocation IdentL, IdentifierInfo *II,
5347	SourceLocation GnuLabelL) {
5348	assert(GnuLabelL != IdentL && "Use this only for GNU local labels");
5349	return new (C, DC) LabelDecl(DC, IdentL, II, nullptr, GnuLabelL);
5350	}
5351
5352	LabelDecl *LabelDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5353	return new (C, ID) LabelDecl(nullptr, SourceLocation(), nullptr, nullptr,
5354	SourceLocation());
5355	}
5356
5357	void LabelDecl::setMSAsmLabel(StringRef Name) {
5358	char *Buffer = new (getASTContext(), 1) char[Name.size() + 1];
5359	memcpy(dest: Buffer, src: Name.data(), n: Name.size());
5360	Buffer[Name.size()] = '\0';
5361	MSAsmName = Buffer;
5362	}
5363
5364	void ValueDecl::anchor() {}
5365
5366	bool ValueDecl::isWeak() const {
5367	auto *MostRecent = getMostRecentDecl();
5368	return MostRecent->hasAttr<WeakAttr>() ||
5369	MostRecent->hasAttr<WeakRefAttr>() || isWeakImported();
5370	}
5371
5372	bool ValueDecl::isInitCapture() const {
5373	if (auto *Var = llvm::dyn_cast<VarDecl>(Val: this))
5374	return Var->isInitCapture();
5375	return false;
5376	}
5377
5378	void ImplicitParamDecl::anchor() {}
5379
5380	ImplicitParamDecl *ImplicitParamDecl::Create(ASTContext &C, DeclContext *DC,
5381	SourceLocation IdLoc,
5382	IdentifierInfo *Id, QualType Type,
5383	ImplicitParamKind ParamKind) {
5384	return new (C, DC) ImplicitParamDecl(C, DC, IdLoc, Id, Type, ParamKind);
5385	}
5386
5387	ImplicitParamDecl *ImplicitParamDecl::Create(ASTContext &C, QualType Type,
5388	ImplicitParamKind ParamKind) {
5389	return new (C, nullptr) ImplicitParamDecl(C, Type, ParamKind);
5390	}
5391
5392	ImplicitParamDecl *ImplicitParamDecl::CreateDeserialized(ASTContext &C,
5393	Decl::DeclID ID) {
5394	return new (C, ID) ImplicitParamDecl(C, QualType(), ImplicitParamKind::Other);
5395	}
5396
5397	FunctionDecl *
5398	FunctionDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation StartLoc,
5399	const DeclarationNameInfo &NameInfo, QualType T,
5400	TypeSourceInfo *TInfo, StorageClass SC, bool UsesFPIntrin,
5401	bool isInlineSpecified, bool hasWrittenPrototype,
5402	ConstexprSpecKind ConstexprKind,
5403	Expr *TrailingRequiresClause) {
5404	FunctionDecl *New = new (C, DC) FunctionDecl(
5405	Function, C, DC, StartLoc, NameInfo, T, TInfo, SC, UsesFPIntrin,
5406	isInlineSpecified, ConstexprKind, TrailingRequiresClause);
5407	New->setHasWrittenPrototype(hasWrittenPrototype);
5408	return New;
5409	}
5410
5411	FunctionDecl *FunctionDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5412	return new (C, ID) FunctionDecl(
5413	Function, C, nullptr, SourceLocation(), DeclarationNameInfo(), QualType(),
5414	nullptr, SC_None, false, false, ConstexprSpecKind::Unspecified, nullptr);
5415	}
5416
5417	BlockDecl *BlockDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L) {
5418	return new (C, DC) BlockDecl(DC, L);
5419	}
5420
5421	BlockDecl *BlockDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5422	return new (C, ID) BlockDecl(nullptr, SourceLocation());
5423	}
5424
5425	CapturedDecl::CapturedDecl(DeclContext *DC, unsigned NumParams)
5426	: Decl(Captured, DC, SourceLocation()), DeclContext(Captured),
5427	NumParams(NumParams), ContextParam(0), BodyAndNothrow(nullptr, false) {}
5428
5429	CapturedDecl *CapturedDecl::Create(ASTContext &C, DeclContext *DC,
5430	unsigned NumParams) {
5431	return new (C, DC, additionalSizeToAlloc<ImplicitParamDecl *>(Counts: NumParams))
5432	CapturedDecl(DC, NumParams);
5433	}
5434
5435	CapturedDecl *CapturedDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID,
5436	unsigned NumParams) {
5437	return new (C, ID, additionalSizeToAlloc<ImplicitParamDecl *>(Counts: NumParams))
5438	CapturedDecl(nullptr, NumParams);
5439	}
5440
5441	Stmt *CapturedDecl::getBody() const { return BodyAndNothrow.getPointer(); }
5442	void CapturedDecl::setBody(Stmt *B) { BodyAndNothrow.setPointer(B); }
5443
5444	bool CapturedDecl::isNothrow() const { return BodyAndNothrow.getInt(); }
5445	void CapturedDecl::setNothrow(bool Nothrow) { BodyAndNothrow.setInt(Nothrow); }
5446
5447	EnumConstantDecl::EnumConstantDecl(const ASTContext &C, DeclContext *DC,
5448	SourceLocation L, IdentifierInfo *Id,
5449	QualType T, Expr *E, const llvm::APSInt &V)
5450	: ValueDecl(EnumConstant, DC, L, Id, T), Init((Stmt *)E) {
5451	setInitVal(C, V);
5452	}
5453
5454	EnumConstantDecl *EnumConstantDecl::Create(ASTContext &C, EnumDecl *CD,
5455	SourceLocation L,
5456	IdentifierInfo *Id, QualType T,
5457	Expr *E, const llvm::APSInt &V) {
5458	return new (C, CD) EnumConstantDecl(C, CD, L, Id, T, E, V);
5459	}
5460
5461	EnumConstantDecl *
5462	EnumConstantDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5463	return new (C, ID) EnumConstantDecl(C, nullptr, SourceLocation(), nullptr,
5464	QualType(), nullptr, llvm::APSInt());
5465	}
5466
5467	void IndirectFieldDecl::anchor() {}
5468
5469	IndirectFieldDecl::IndirectFieldDecl(ASTContext &C, DeclContext *DC,
5470	SourceLocation L, DeclarationName N,
5471	QualType T,
5472	MutableArrayRef<NamedDecl *> CH)
5473	: ValueDecl(IndirectField, DC, L, N, T), Chaining(CH.data()),
5474	ChainingSize(CH.size()) {
5475	// In C++, indirect field declarations conflict with tag declarations in the
5476	// same scope, so add them to IDNS_Tag so that tag redeclaration finds them.
5477	if (C.getLangOpts().CPlusPlus)
5478	IdentifierNamespace |= IDNS_Tag;
5479	}
5480
5481	IndirectFieldDecl *
5482	IndirectFieldDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L,
5483	const IdentifierInfo *Id, QualType T,
5484	llvm::MutableArrayRef<NamedDecl *> CH) {
5485	return new (C, DC) IndirectFieldDecl(C, DC, L, Id, T, CH);
5486	}
5487
5488	IndirectFieldDecl *IndirectFieldDecl::CreateDeserialized(ASTContext &C,
5489	Decl::DeclID ID) {
5490	return new (C, ID)
5491	IndirectFieldDecl(C, nullptr, SourceLocation(), DeclarationName(),
5492	QualType(), std::nullopt);
5493	}
5494
5495	SourceRange EnumConstantDecl::getSourceRange() const {
5496	SourceLocation End = getLocation();
5497	if (Init)
5498	End = Init->getEndLoc();
5499	return SourceRange(getLocation(), End);
5500	}
5501
5502	void TypeDecl::anchor() {}
5503
5504	TypedefDecl *TypedefDecl::Create(ASTContext &C, DeclContext *DC,
5505	SourceLocation StartLoc, SourceLocation IdLoc,
5506	const IdentifierInfo *Id,
5507	TypeSourceInfo *TInfo) {
5508	return new (C, DC) TypedefDecl(C, DC, StartLoc, IdLoc, Id, TInfo);
5509	}
5510
5511	void TypedefNameDecl::anchor() {}
5512
5513	TagDecl *TypedefNameDecl::getAnonDeclWithTypedefName(bool AnyRedecl) const {
5514	if (auto *TT = getTypeSourceInfo()->getType()->getAs<TagType>()) {
5515	auto *OwningTypedef = TT->getDecl()->getTypedefNameForAnonDecl();
5516	auto *ThisTypedef = this;
5517	if (AnyRedecl && OwningTypedef) {
5518	OwningTypedef = OwningTypedef->getCanonicalDecl();
5519	ThisTypedef = ThisTypedef->getCanonicalDecl();
5520	}
5521	if (OwningTypedef == ThisTypedef)
5522	return TT->getDecl();
5523	}
5524
5525	return nullptr;
5526	}
5527
5528	bool TypedefNameDecl::isTransparentTagSlow() const {
5529	auto determineIsTransparent = [&]() {
5530	if (auto *TT = getUnderlyingType()->getAs<TagType>()) {
5531	if (auto *TD = TT->getDecl()) {
5532	if (TD->getName() != getName())
5533	return false;
5534	SourceLocation TTLoc = getLocation();
5535	SourceLocation TDLoc = TD->getLocation();
5536	if (!TTLoc.isMacroID() || !TDLoc.isMacroID())
5537	return false;
5538	SourceManager &SM = getASTContext().getSourceManager();
5539	return SM.getSpellingLoc(TTLoc) == SM.getSpellingLoc(TDLoc);
5540	}
5541	}
5542	return false;
5543	};
5544
5545	bool isTransparent = determineIsTransparent();
5546	MaybeModedTInfo.setInt((isTransparent << 1) | 1);
5547	return isTransparent;
5548	}
5549
5550	TypedefDecl *TypedefDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5551	return new (C, ID) TypedefDecl(C, nullptr, SourceLocation(), SourceLocation(),
5552	nullptr, nullptr);
5553	}
5554
5555	TypeAliasDecl *TypeAliasDecl::Create(ASTContext &C, DeclContext *DC,
5556	SourceLocation StartLoc,
5557	SourceLocation IdLoc,
5558	const IdentifierInfo *Id,
5559	TypeSourceInfo *TInfo) {
5560	return new (C, DC) TypeAliasDecl(C, DC, StartLoc, IdLoc, Id, TInfo);
5561	}
5562
5563	TypeAliasDecl *TypeAliasDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5564	return new (C, ID) TypeAliasDecl(C, nullptr, SourceLocation(),
5565	SourceLocation(), nullptr, nullptr);
5566	}
5567
5568	SourceRange TypedefDecl::getSourceRange() const {
5569	SourceLocation RangeEnd = getLocation();
5570	if (TypeSourceInfo *TInfo = getTypeSourceInfo()) {
5571	if (typeIsPostfix(QT: TInfo->getType()))
5572	RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
5573	}
5574	return SourceRange(getBeginLoc(), RangeEnd);
5575	}
5576
5577	SourceRange TypeAliasDecl::getSourceRange() const {
5578	SourceLocation RangeEnd = getBeginLoc();
5579	if (TypeSourceInfo *TInfo = getTypeSourceInfo())
5580	RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
5581	return SourceRange(getBeginLoc(), RangeEnd);
5582	}
5583
5584	void FileScopeAsmDecl::anchor() {}
5585
5586	FileScopeAsmDecl *FileScopeAsmDecl::Create(ASTContext &C, DeclContext *DC,
5587	StringLiteral *Str,
5588	SourceLocation AsmLoc,
5589	SourceLocation RParenLoc) {
5590	return new (C, DC) FileScopeAsmDecl(DC, Str, AsmLoc, RParenLoc);
5591	}
5592
5593	FileScopeAsmDecl *FileScopeAsmDecl::CreateDeserialized(ASTContext &C,
5594	Decl::DeclID ID) {
5595	return new (C, ID) FileScopeAsmDecl(nullptr, nullptr, SourceLocation(),
5596	SourceLocation());
5597	}
5598
5599	void TopLevelStmtDecl::anchor() {}
5600
5601	TopLevelStmtDecl *TopLevelStmtDecl::Create(ASTContext &C, Stmt *Statement) {
5602	assert(C.getLangOpts().IncrementalExtensions &&
5603	"Must be used only in incremental mode");
5604
5605	SourceLocation Loc = Statement ? Statement->getBeginLoc() : SourceLocation();
5606	DeclContext *DC = C.getTranslationUnitDecl();
5607
5608	return new (C, DC) TopLevelStmtDecl(DC, Loc, Statement);
5609	}
5610
5611	TopLevelStmtDecl *TopLevelStmtDecl::CreateDeserialized(ASTContext &C,
5612	Decl::DeclID ID) {
5613	return new (C, ID)
5614	TopLevelStmtDecl(/*DC=*/nullptr, SourceLocation(), /*S=*/nullptr);
5615	}
5616
5617	SourceRange TopLevelStmtDecl::getSourceRange() const {
5618	return SourceRange(getLocation(), Statement->getEndLoc());
5619	}
5620
5621	void TopLevelStmtDecl::setStmt(Stmt *S) {
5622	assert(S);
5623	Statement = S;
5624	setLocation(Statement->getBeginLoc());
5625	}
5626
5627	void EmptyDecl::anchor() {}
5628
5629	EmptyDecl *EmptyDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L) {
5630	return new (C, DC) EmptyDecl(DC, L);
5631	}
5632
5633	EmptyDecl *EmptyDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5634	return new (C, ID) EmptyDecl(nullptr, SourceLocation());
5635	}
5636
5637	HLSLBufferDecl::HLSLBufferDecl(DeclContext *DC, bool CBuffer,
5638	SourceLocation KwLoc, IdentifierInfo *ID,
5639	SourceLocation IDLoc, SourceLocation LBrace)
5640	: NamedDecl(Decl::Kind::HLSLBuffer, DC, IDLoc, DeclarationName(ID)),
5641	DeclContext(Decl::Kind::HLSLBuffer), LBraceLoc(LBrace), KwLoc(KwLoc),
5642	IsCBuffer(CBuffer) {}
5643
5644	HLSLBufferDecl *HLSLBufferDecl::Create(ASTContext &C,
5645	DeclContext *LexicalParent, bool CBuffer,
5646	SourceLocation KwLoc, IdentifierInfo *ID,
5647	SourceLocation IDLoc,
5648	SourceLocation LBrace) {
5649	// For hlsl like this
5650	// cbuffer A {
5651	// cbuffer B {
5652	// }
5653	// }
5654	// compiler should treat it as
5655	// cbuffer A {
5656	// }
5657	// cbuffer B {
5658	// }
5659	// FIXME: support nested buffers if required for back-compat.
5660	DeclContext *DC = LexicalParent;
5661	HLSLBufferDecl *Result =
5662	new (C, DC) HLSLBufferDecl(DC, CBuffer, KwLoc, ID, IDLoc, LBrace);
5663	return Result;
5664	}
5665
5666	HLSLBufferDecl *HLSLBufferDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5667	return new (C, ID) HLSLBufferDecl(nullptr, false, SourceLocation(), nullptr,
5668	SourceLocation(), SourceLocation());
5669	}
5670
5671	//===----------------------------------------------------------------------===//
5672	// ImportDecl Implementation
5673	//===----------------------------------------------------------------------===//
5674
5675	/// Retrieve the number of module identifiers needed to name the given
5676	/// module.
5677	static unsigned getNumModuleIdentifiers(Module *Mod) {
5678	unsigned Result = 1;
5679	while (Mod->Parent) {
5680	Mod = Mod->Parent;
5681	++Result;
5682	}
5683	return Result;
5684	}
5685
5686	ImportDecl::ImportDecl(DeclContext *DC, SourceLocation StartLoc,
5687	Module *Imported,
5688	ArrayRef<SourceLocation> IdentifierLocs)
5689	: Decl(Import, DC, StartLoc), ImportedModule(Imported),
5690	NextLocalImportAndComplete(nullptr, true) {
5691	assert(getNumModuleIdentifiers(Imported) == IdentifierLocs.size());
5692	auto *StoredLocs = getTrailingObjects<SourceLocation>();
5693	std::uninitialized_copy(IdentifierLocs.begin(), IdentifierLocs.end(),
5694	StoredLocs);
5695	}
5696
5697	ImportDecl::ImportDecl(DeclContext *DC, SourceLocation StartLoc,
5698	Module *Imported, SourceLocation EndLoc)
5699	: Decl(Import, DC, StartLoc), ImportedModule(Imported),
5700	NextLocalImportAndComplete(nullptr, false) {
5701	*getTrailingObjects<SourceLocation>() = EndLoc;
5702	}
5703
5704	ImportDecl *ImportDecl::Create(ASTContext &C, DeclContext *DC,
5705	SourceLocation StartLoc, Module *Imported,
5706	ArrayRef<SourceLocation> IdentifierLocs) {
5707	return new (C, DC,
5708	additionalSizeToAlloc<SourceLocation>(Counts: IdentifierLocs.size()))
5709	ImportDecl(DC, StartLoc, Imported, IdentifierLocs);
5710	}
5711
5712	ImportDecl *ImportDecl::CreateImplicit(ASTContext &C, DeclContext *DC,
5713	SourceLocation StartLoc,
5714	Module *Imported,
5715	SourceLocation EndLoc) {
5716	ImportDecl *Import = new (C, DC, additionalSizeToAlloc<SourceLocation>(Counts: 1))
5717	ImportDecl(DC, StartLoc, Imported, EndLoc);
5718	Import->setImplicit();
5719	return Import;
5720	}
5721
5722	ImportDecl *ImportDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID,
5723	unsigned NumLocations) {
5724	return new (C, ID, additionalSizeToAlloc<SourceLocation>(Counts: NumLocations))
5725	ImportDecl(EmptyShell());
5726	}
5727
5728	ArrayRef<SourceLocation> ImportDecl::getIdentifierLocs() const {
5729	if (!isImportComplete())
5730	return std::nullopt;
5731
5732	const auto *StoredLocs = getTrailingObjects<SourceLocation>();
5733	return llvm::ArrayRef(StoredLocs,
5734	getNumModuleIdentifiers(Mod: getImportedModule()));
5735	}
5736
5737	SourceRange ImportDecl::getSourceRange() const {
5738	if (!isImportComplete())
5739	return SourceRange(getLocation(), *getTrailingObjects<SourceLocation>());
5740
5741	return SourceRange(getLocation(), getIdentifierLocs().back());
5742	}
5743
5744	//===----------------------------------------------------------------------===//
5745	// ExportDecl Implementation
5746	//===----------------------------------------------------------------------===//
5747
5748	void ExportDecl::anchor() {}
5749
5750	ExportDecl *ExportDecl::Create(ASTContext &C, DeclContext *DC,
5751	SourceLocation ExportLoc) {
5752	return new (C, DC) ExportDecl(DC, ExportLoc);
5753	}
5754
5755	ExportDecl *ExportDecl::CreateDeserialized(ASTContext &C, Decl::DeclID ID) {
5756	return new (C, ID) ExportDecl(nullptr, SourceLocation());
5757	}
5758