Bug Summary

File:clang/lib/Sema/SemaTemplate.cpp
Warning:line 1898, column 5
Called C++ object pointer is null

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaTemplate.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/include -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/include -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2019-12-09-002921-48462-1 -x c++ /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp
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1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===//
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// This file implements semantic analysis for C++ templates.
9//===----------------------------------------------------------------------===//
10
11#include "TreeTransform.h"
12#include "clang/AST/ASTConsumer.h"
13#include "clang/AST/ASTContext.h"
14#include "clang/AST/DeclFriend.h"
15#include "clang/AST/DeclTemplate.h"
16#include "clang/AST/Expr.h"
17#include "clang/AST/ExprCXX.h"
18#include "clang/AST/RecursiveASTVisitor.h"
19#include "clang/AST/TypeVisitor.h"
20#include "clang/Basic/Builtins.h"
21#include "clang/Basic/LangOptions.h"
22#include "clang/Basic/PartialDiagnostic.h"
23#include "clang/Basic/Stack.h"
24#include "clang/Basic/TargetInfo.h"
25#include "clang/Sema/DeclSpec.h"
26#include "clang/Sema/Lookup.h"
27#include "clang/Sema/Overload.h"
28#include "clang/Sema/ParsedTemplate.h"
29#include "clang/Sema/Scope.h"
30#include "clang/Sema/SemaInternal.h"
31#include "clang/Sema/Template.h"
32#include "clang/Sema/TemplateDeduction.h"
33#include "llvm/ADT/SmallBitVector.h"
34#include "llvm/ADT/SmallString.h"
35#include "llvm/ADT/StringExtras.h"
36
37#include <iterator>
38using namespace clang;
39using namespace sema;
40
41// Exported for use by Parser.
42SourceRange
43clang::getTemplateParamsRange(TemplateParameterList const * const *Ps,
44 unsigned N) {
45 if (!N) return SourceRange();
46 return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc());
47}
48
49/// \brief Determine whether the declaration found is acceptable as the name
50/// of a template and, if so, return that template declaration. Otherwise,
51/// returns null.
52///
53/// Note that this may return an UnresolvedUsingValueDecl if AllowDependent
54/// is true. In all other cases it will return a TemplateDecl (or null).
55NamedDecl *Sema::getAsTemplateNameDecl(NamedDecl *D,
56 bool AllowFunctionTemplates,
57 bool AllowDependent) {
58 D = D->getUnderlyingDecl();
59
60 if (isa<TemplateDecl>(D)) {
61 if (!AllowFunctionTemplates && isa<FunctionTemplateDecl>(D))
62 return nullptr;
63
64 return D;
65 }
66
67 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
68 // C++ [temp.local]p1:
69 // Like normal (non-template) classes, class templates have an
70 // injected-class-name (Clause 9). The injected-class-name
71 // can be used with or without a template-argument-list. When
72 // it is used without a template-argument-list, it is
73 // equivalent to the injected-class-name followed by the
74 // template-parameters of the class template enclosed in
75 // <>. When it is used with a template-argument-list, it
76 // refers to the specified class template specialization,
77 // which could be the current specialization or another
78 // specialization.
79 if (Record->isInjectedClassName()) {
80 Record = cast<CXXRecordDecl>(Record->getDeclContext());
81 if (Record->getDescribedClassTemplate())
82 return Record->getDescribedClassTemplate();
83
84 if (ClassTemplateSpecializationDecl *Spec
85 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
86 return Spec->getSpecializedTemplate();
87 }
88
89 return nullptr;
90 }
91
92 // 'using Dependent::foo;' can resolve to a template name.
93 // 'using typename Dependent::foo;' cannot (not even if 'foo' is an
94 // injected-class-name).
95 if (AllowDependent && isa<UnresolvedUsingValueDecl>(D))
96 return D;
97
98 return nullptr;
99}
100
101void Sema::FilterAcceptableTemplateNames(LookupResult &R,
102 bool AllowFunctionTemplates,
103 bool AllowDependent) {
104 LookupResult::Filter filter = R.makeFilter();
105 while (filter.hasNext()) {
106 NamedDecl *Orig = filter.next();
107 if (!getAsTemplateNameDecl(Orig, AllowFunctionTemplates, AllowDependent))
108 filter.erase();
109 }
110 filter.done();
111}
112
113bool Sema::hasAnyAcceptableTemplateNames(LookupResult &R,
114 bool AllowFunctionTemplates,
115 bool AllowDependent,
116 bool AllowNonTemplateFunctions) {
117 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
118 if (getAsTemplateNameDecl(*I, AllowFunctionTemplates, AllowDependent))
119 return true;
120 if (AllowNonTemplateFunctions &&
121 isa<FunctionDecl>((*I)->getUnderlyingDecl()))
122 return true;
123 }
124
125 return false;
126}
127
128TemplateNameKind Sema::isTemplateName(Scope *S,
129 CXXScopeSpec &SS,
130 bool hasTemplateKeyword,
131 const UnqualifiedId &Name,
132 ParsedType ObjectTypePtr,
133 bool EnteringContext,
134 TemplateTy &TemplateResult,
135 bool &MemberOfUnknownSpecialization) {
136 assert(getLangOpts().CPlusPlus && "No template names in C!")((getLangOpts().CPlusPlus && "No template names in C!"
) ? static_cast<void> (0) : __assert_fail ("getLangOpts().CPlusPlus && \"No template names in C!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 136, __PRETTY_FUNCTION__))
;
137
138 DeclarationName TName;
139 MemberOfUnknownSpecialization = false;
140
141 switch (Name.getKind()) {
142 case UnqualifiedIdKind::IK_Identifier:
143 TName = DeclarationName(Name.Identifier);
144 break;
145
146 case UnqualifiedIdKind::IK_OperatorFunctionId:
147 TName = Context.DeclarationNames.getCXXOperatorName(
148 Name.OperatorFunctionId.Operator);
149 break;
150
151 case UnqualifiedIdKind::IK_LiteralOperatorId:
152 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
153 break;
154
155 default:
156 return TNK_Non_template;
157 }
158
159 QualType ObjectType = ObjectTypePtr.get();
160
161 AssumedTemplateKind AssumedTemplate;
162 LookupResult R(*this, TName, Name.getBeginLoc(), LookupOrdinaryName);
163 if (LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
164 MemberOfUnknownSpecialization, SourceLocation(),
165 &AssumedTemplate))
166 return TNK_Non_template;
167
168 if (AssumedTemplate != AssumedTemplateKind::None) {
169 TemplateResult = TemplateTy::make(Context.getAssumedTemplateName(TName));
170 // Let the parser know whether we found nothing or found functions; if we
171 // found nothing, we want to more carefully check whether this is actually
172 // a function template name versus some other kind of undeclared identifier.
173 return AssumedTemplate == AssumedTemplateKind::FoundNothing
174 ? TNK_Undeclared_template
175 : TNK_Function_template;
176 }
177
178 if (R.empty())
179 return TNK_Non_template;
180
181 NamedDecl *D = nullptr;
182 if (R.isAmbiguous()) {
183 // If we got an ambiguity involving a non-function template, treat this
184 // as a template name, and pick an arbitrary template for error recovery.
185 bool AnyFunctionTemplates = false;
186 for (NamedDecl *FoundD : R) {
187 if (NamedDecl *FoundTemplate = getAsTemplateNameDecl(FoundD)) {
188 if (isa<FunctionTemplateDecl>(FoundTemplate))
189 AnyFunctionTemplates = true;
190 else {
191 D = FoundTemplate;
192 break;
193 }
194 }
195 }
196
197 // If we didn't find any templates at all, this isn't a template name.
198 // Leave the ambiguity for a later lookup to diagnose.
199 if (!D && !AnyFunctionTemplates) {
200 R.suppressDiagnostics();
201 return TNK_Non_template;
202 }
203
204 // If the only templates were function templates, filter out the rest.
205 // We'll diagnose the ambiguity later.
206 if (!D)
207 FilterAcceptableTemplateNames(R);
208 }
209
210 // At this point, we have either picked a single template name declaration D
211 // or we have a non-empty set of results R containing either one template name
212 // declaration or a set of function templates.
213
214 TemplateName Template;
215 TemplateNameKind TemplateKind;
216
217 unsigned ResultCount = R.end() - R.begin();
218 if (!D && ResultCount > 1) {
219 // We assume that we'll preserve the qualifier from a function
220 // template name in other ways.
221 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
222 TemplateKind = TNK_Function_template;
223
224 // We'll do this lookup again later.
225 R.suppressDiagnostics();
226 } else {
227 if (!D) {
228 D = getAsTemplateNameDecl(*R.begin());
229 assert(D && "unambiguous result is not a template name")((D && "unambiguous result is not a template name") ?
static_cast<void> (0) : __assert_fail ("D && \"unambiguous result is not a template name\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 229, __PRETTY_FUNCTION__))
;
230 }
231
232 if (isa<UnresolvedUsingValueDecl>(D)) {
233 // We don't yet know whether this is a template-name or not.
234 MemberOfUnknownSpecialization = true;
235 return TNK_Non_template;
236 }
237
238 TemplateDecl *TD = cast<TemplateDecl>(D);
239
240 if (SS.isSet() && !SS.isInvalid()) {
241 NestedNameSpecifier *Qualifier = SS.getScopeRep();
242 Template = Context.getQualifiedTemplateName(Qualifier,
243 hasTemplateKeyword, TD);
244 } else {
245 Template = TemplateName(TD);
246 }
247
248 if (isa<FunctionTemplateDecl>(TD)) {
249 TemplateKind = TNK_Function_template;
250
251 // We'll do this lookup again later.
252 R.suppressDiagnostics();
253 } else {
254 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) ||((isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl
>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl
>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl
>(TD)) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl>(TD)"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 256, __PRETTY_FUNCTION__))
255 isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl>(TD) ||((isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl
>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl
>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl
>(TD)) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl>(TD)"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 256, __PRETTY_FUNCTION__))
256 isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl>(TD))((isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl
>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl
>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl
>(TD)) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) || isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl>(TD) || isa<BuiltinTemplateDecl>(TD) || isa<ConceptDecl>(TD)"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 256, __PRETTY_FUNCTION__))
;
257 TemplateKind =
258 isa<VarTemplateDecl>(TD) ? TNK_Var_template :
259 isa<ConceptDecl>(TD) ? TNK_Concept_template :
260 TNK_Type_template;
261 }
262 }
263
264 TemplateResult = TemplateTy::make(Template);
265 return TemplateKind;
266}
267
268bool Sema::isDeductionGuideName(Scope *S, const IdentifierInfo &Name,
269 SourceLocation NameLoc,
270 ParsedTemplateTy *Template) {
271 CXXScopeSpec SS;
272 bool MemberOfUnknownSpecialization = false;
273
274 // We could use redeclaration lookup here, but we don't need to: the
275 // syntactic form of a deduction guide is enough to identify it even
276 // if we can't look up the template name at all.
277 LookupResult R(*this, DeclarationName(&Name), NameLoc, LookupOrdinaryName);
278 if (LookupTemplateName(R, S, SS, /*ObjectType*/ QualType(),
279 /*EnteringContext*/ false,
280 MemberOfUnknownSpecialization))
281 return false;
282
283 if (R.empty()) return false;
284 if (R.isAmbiguous()) {
285 // FIXME: Diagnose an ambiguity if we find at least one template.
286 R.suppressDiagnostics();
287 return false;
288 }
289
290 // We only treat template-names that name type templates as valid deduction
291 // guide names.
292 TemplateDecl *TD = R.getAsSingle<TemplateDecl>();
293 if (!TD || !getAsTypeTemplateDecl(TD))
294 return false;
295
296 if (Template)
297 *Template = TemplateTy::make(TemplateName(TD));
298 return true;
299}
300
301bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
302 SourceLocation IILoc,
303 Scope *S,
304 const CXXScopeSpec *SS,
305 TemplateTy &SuggestedTemplate,
306 TemplateNameKind &SuggestedKind) {
307 // We can't recover unless there's a dependent scope specifier preceding the
308 // template name.
309 // FIXME: Typo correction?
310 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
311 computeDeclContext(*SS))
312 return false;
313
314 // The code is missing a 'template' keyword prior to the dependent template
315 // name.
316 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
317 Diag(IILoc, diag::err_template_kw_missing)
318 << Qualifier << II.getName()
319 << FixItHint::CreateInsertion(IILoc, "template ");
320 SuggestedTemplate
321 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
322 SuggestedKind = TNK_Dependent_template_name;
323 return true;
324}
325
326bool Sema::LookupTemplateName(LookupResult &Found,
327 Scope *S, CXXScopeSpec &SS,
328 QualType ObjectType,
329 bool EnteringContext,
330 bool &MemberOfUnknownSpecialization,
331 SourceLocation TemplateKWLoc,
332 AssumedTemplateKind *ATK) {
333 if (ATK)
334 *ATK = AssumedTemplateKind::None;
335
336 Found.setTemplateNameLookup(true);
337
338 // Determine where to perform name lookup
339 MemberOfUnknownSpecialization = false;
340 DeclContext *LookupCtx = nullptr;
341 bool IsDependent = false;
342 if (!ObjectType.isNull()) {
343 // This nested-name-specifier occurs in a member access expression, e.g.,
344 // x->B::f, and we are looking into the type of the object.
345 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist")((!SS.isSet() && "ObjectType and scope specifier cannot coexist"
) ? static_cast<void> (0) : __assert_fail ("!SS.isSet() && \"ObjectType and scope specifier cannot coexist\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 345, __PRETTY_FUNCTION__))
;
346 LookupCtx = computeDeclContext(ObjectType);
347 IsDependent = !LookupCtx && ObjectType->isDependentType();
348 assert((IsDependent || !ObjectType->isIncompleteType() ||(((IsDependent || !ObjectType->isIncompleteType() || ObjectType
->castAs<TagType>()->isBeingDefined()) &&
"Caller should have completed object type") ? static_cast<
void> (0) : __assert_fail ("(IsDependent || !ObjectType->isIncompleteType() || ObjectType->castAs<TagType>()->isBeingDefined()) && \"Caller should have completed object type\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 350, __PRETTY_FUNCTION__))
349 ObjectType->castAs<TagType>()->isBeingDefined()) &&(((IsDependent || !ObjectType->isIncompleteType() || ObjectType
->castAs<TagType>()->isBeingDefined()) &&
"Caller should have completed object type") ? static_cast<
void> (0) : __assert_fail ("(IsDependent || !ObjectType->isIncompleteType() || ObjectType->castAs<TagType>()->isBeingDefined()) && \"Caller should have completed object type\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 350, __PRETTY_FUNCTION__))
350 "Caller should have completed object type")(((IsDependent || !ObjectType->isIncompleteType() || ObjectType
->castAs<TagType>()->isBeingDefined()) &&
"Caller should have completed object type") ? static_cast<
void> (0) : __assert_fail ("(IsDependent || !ObjectType->isIncompleteType() || ObjectType->castAs<TagType>()->isBeingDefined()) && \"Caller should have completed object type\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 350, __PRETTY_FUNCTION__))
;
351
352 // Template names cannot appear inside an Objective-C class or object type
353 // or a vector type.
354 //
355 // FIXME: This is wrong. For example:
356 //
357 // template<typename T> using Vec = T __attribute__((ext_vector_type(4)));
358 // Vec<int> vi;
359 // vi.Vec<int>::~Vec<int>();
360 //
361 // ... should be accepted but we will not treat 'Vec' as a template name
362 // here. The right thing to do would be to check if the name is a valid
363 // vector component name, and look up a template name if not. And similarly
364 // for lookups into Objective-C class and object types, where the same
365 // problem can arise.
366 if (ObjectType->isObjCObjectOrInterfaceType() ||
367 ObjectType->isVectorType()) {
368 Found.clear();
369 return false;
370 }
371 } else if (SS.isSet()) {
372 // This nested-name-specifier occurs after another nested-name-specifier,
373 // so long into the context associated with the prior nested-name-specifier.
374 LookupCtx = computeDeclContext(SS, EnteringContext);
375 IsDependent = !LookupCtx;
376
377 // The declaration context must be complete.
378 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
379 return true;
380 }
381
382 bool ObjectTypeSearchedInScope = false;
383 bool AllowFunctionTemplatesInLookup = true;
384 if (LookupCtx) {
385 // Perform "qualified" name lookup into the declaration context we
386 // computed, which is either the type of the base of a member access
387 // expression or the declaration context associated with a prior
388 // nested-name-specifier.
389 LookupQualifiedName(Found, LookupCtx);
390
391 // FIXME: The C++ standard does not clearly specify what happens in the
392 // case where the object type is dependent, and implementations vary. In
393 // Clang, we treat a name after a . or -> as a template-name if lookup
394 // finds a non-dependent member or member of the current instantiation that
395 // is a type template, or finds no such members and lookup in the context
396 // of the postfix-expression finds a type template. In the latter case, the
397 // name is nonetheless dependent, and we may resolve it to a member of an
398 // unknown specialization when we come to instantiate the template.
399 IsDependent |= Found.wasNotFoundInCurrentInstantiation();
400 }
401
402 if (!SS.isSet() && (ObjectType.isNull() || Found.empty())) {
403 // C++ [basic.lookup.classref]p1:
404 // In a class member access expression (5.2.5), if the . or -> token is
405 // immediately followed by an identifier followed by a <, the
406 // identifier must be looked up to determine whether the < is the
407 // beginning of a template argument list (14.2) or a less-than operator.
408 // The identifier is first looked up in the class of the object
409 // expression. If the identifier is not found, it is then looked up in
410 // the context of the entire postfix-expression and shall name a class
411 // template.
412 if (S)
413 LookupName(Found, S);
414
415 if (!ObjectType.isNull()) {
416 // FIXME: We should filter out all non-type templates here, particularly
417 // variable templates and concepts. But the exclusion of alias templates
418 // and template template parameters is a wording defect.
419 AllowFunctionTemplatesInLookup = false;
420 ObjectTypeSearchedInScope = true;
421 }
422
423 IsDependent |= Found.wasNotFoundInCurrentInstantiation();
424 }
425
426 if (Found.isAmbiguous())
427 return false;
428
429 if (ATK && !SS.isSet() && ObjectType.isNull() && TemplateKWLoc.isInvalid()) {
430 // C++2a [temp.names]p2:
431 // A name is also considered to refer to a template if it is an
432 // unqualified-id followed by a < and name lookup finds either one or more
433 // functions or finds nothing.
434 //
435 // To keep our behavior consistent, we apply the "finds nothing" part in
436 // all language modes, and diagnose the empty lookup in ActOnCallExpr if we
437 // successfully form a call to an undeclared template-id.
438 bool AllFunctions =
439 getLangOpts().CPlusPlus2a &&
440 std::all_of(Found.begin(), Found.end(), [](NamedDecl *ND) {
441 return isa<FunctionDecl>(ND->getUnderlyingDecl());
442 });
443 if (AllFunctions || (Found.empty() && !IsDependent)) {
444 // If lookup found any functions, or if this is a name that can only be
445 // used for a function, then strongly assume this is a function
446 // template-id.
447 *ATK = (Found.empty() && Found.getLookupName().isIdentifier())
448 ? AssumedTemplateKind::FoundNothing
449 : AssumedTemplateKind::FoundFunctions;
450 Found.clear();
451 return false;
452 }
453 }
454
455 if (Found.empty() && !IsDependent) {
456 // If we did not find any names, attempt to correct any typos.
457 DeclarationName Name = Found.getLookupName();
458 Found.clear();
459 // Simple filter callback that, for keywords, only accepts the C++ *_cast
460 DefaultFilterCCC FilterCCC{};
461 FilterCCC.WantTypeSpecifiers = false;
462 FilterCCC.WantExpressionKeywords = false;
463 FilterCCC.WantRemainingKeywords = false;
464 FilterCCC.WantCXXNamedCasts = true;
465 if (TypoCorrection Corrected =
466 CorrectTypo(Found.getLookupNameInfo(), Found.getLookupKind(), S,
467 &SS, FilterCCC, CTK_ErrorRecovery, LookupCtx)) {
468 if (auto *ND = Corrected.getFoundDecl())
469 Found.addDecl(ND);
470 FilterAcceptableTemplateNames(Found);
471 if (Found.isAmbiguous()) {
472 Found.clear();
473 } else if (!Found.empty()) {
474 Found.setLookupName(Corrected.getCorrection());
475 if (LookupCtx) {
476 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
477 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
478 Name.getAsString() == CorrectedStr;
479 diagnoseTypo(Corrected, PDiag(diag::err_no_member_template_suggest)
480 << Name << LookupCtx << DroppedSpecifier
481 << SS.getRange());
482 } else {
483 diagnoseTypo(Corrected, PDiag(diag::err_no_template_suggest) << Name);
484 }
485 }
486 }
487 }
488
489 NamedDecl *ExampleLookupResult =
490 Found.empty() ? nullptr : Found.getRepresentativeDecl();
491 FilterAcceptableTemplateNames(Found, AllowFunctionTemplatesInLookup);
492 if (Found.empty()) {
493 if (IsDependent) {
494 MemberOfUnknownSpecialization = true;
495 return false;
496 }
497
498 // If a 'template' keyword was used, a lookup that finds only non-template
499 // names is an error.
500 if (ExampleLookupResult && TemplateKWLoc.isValid()) {
501 Diag(Found.getNameLoc(), diag::err_template_kw_refers_to_non_template)
502 << Found.getLookupName() << SS.getRange();
503 Diag(ExampleLookupResult->getUnderlyingDecl()->getLocation(),
504 diag::note_template_kw_refers_to_non_template)
505 << Found.getLookupName();
506 return true;
507 }
508
509 return false;
510 }
511
512 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope &&
513 !getLangOpts().CPlusPlus11) {
514 // C++03 [basic.lookup.classref]p1:
515 // [...] If the lookup in the class of the object expression finds a
516 // template, the name is also looked up in the context of the entire
517 // postfix-expression and [...]
518 //
519 // Note: C++11 does not perform this second lookup.
520 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
521 LookupOrdinaryName);
522 FoundOuter.setTemplateNameLookup(true);
523 LookupName(FoundOuter, S);
524 // FIXME: We silently accept an ambiguous lookup here, in violation of
525 // [basic.lookup]/1.
526 FilterAcceptableTemplateNames(FoundOuter, /*AllowFunctionTemplates=*/false);
527
528 NamedDecl *OuterTemplate;
529 if (FoundOuter.empty()) {
530 // - if the name is not found, the name found in the class of the
531 // object expression is used, otherwise
532 } else if (FoundOuter.isAmbiguous() || !FoundOuter.isSingleResult() ||
533 !(OuterTemplate =
534 getAsTemplateNameDecl(FoundOuter.getFoundDecl()))) {
535 // - if the name is found in the context of the entire
536 // postfix-expression and does not name a class template, the name
537 // found in the class of the object expression is used, otherwise
538 FoundOuter.clear();
539 } else if (!Found.isSuppressingDiagnostics()) {
540 // - if the name found is a class template, it must refer to the same
541 // entity as the one found in the class of the object expression,
542 // otherwise the program is ill-formed.
543 if (!Found.isSingleResult() ||
544 getAsTemplateNameDecl(Found.getFoundDecl())->getCanonicalDecl() !=
545 OuterTemplate->getCanonicalDecl()) {
546 Diag(Found.getNameLoc(),
547 diag::ext_nested_name_member_ref_lookup_ambiguous)
548 << Found.getLookupName()
549 << ObjectType;
550 Diag(Found.getRepresentativeDecl()->getLocation(),
551 diag::note_ambig_member_ref_object_type)
552 << ObjectType;
553 Diag(FoundOuter.getFoundDecl()->getLocation(),
554 diag::note_ambig_member_ref_scope);
555
556 // Recover by taking the template that we found in the object
557 // expression's type.
558 }
559 }
560 }
561
562 return false;
563}
564
565void Sema::diagnoseExprIntendedAsTemplateName(Scope *S, ExprResult TemplateName,
566 SourceLocation Less,
567 SourceLocation Greater) {
568 if (TemplateName.isInvalid())
569 return;
570
571 DeclarationNameInfo NameInfo;
572 CXXScopeSpec SS;
573 LookupNameKind LookupKind;
574
575 DeclContext *LookupCtx = nullptr;
576 NamedDecl *Found = nullptr;
577 bool MissingTemplateKeyword = false;
578
579 // Figure out what name we looked up.
580 if (auto *DRE = dyn_cast<DeclRefExpr>(TemplateName.get())) {
581 NameInfo = DRE->getNameInfo();
582 SS.Adopt(DRE->getQualifierLoc());
583 LookupKind = LookupOrdinaryName;
584 Found = DRE->getFoundDecl();
585 } else if (auto *ME = dyn_cast<MemberExpr>(TemplateName.get())) {
586 NameInfo = ME->getMemberNameInfo();
587 SS.Adopt(ME->getQualifierLoc());
588 LookupKind = LookupMemberName;
589 LookupCtx = ME->getBase()->getType()->getAsCXXRecordDecl();
590 Found = ME->getMemberDecl();
591 } else if (auto *DSDRE =
592 dyn_cast<DependentScopeDeclRefExpr>(TemplateName.get())) {
593 NameInfo = DSDRE->getNameInfo();
594 SS.Adopt(DSDRE->getQualifierLoc());
595 MissingTemplateKeyword = true;
596 } else if (auto *DSME =
597 dyn_cast<CXXDependentScopeMemberExpr>(TemplateName.get())) {
598 NameInfo = DSME->getMemberNameInfo();
599 SS.Adopt(DSME->getQualifierLoc());
600 MissingTemplateKeyword = true;
601 } else {
602 llvm_unreachable("unexpected kind of potential template name")::llvm::llvm_unreachable_internal("unexpected kind of potential template name"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 602)
;
603 }
604
605 // If this is a dependent-scope lookup, diagnose that the 'template' keyword
606 // was missing.
607 if (MissingTemplateKeyword) {
608 Diag(NameInfo.getBeginLoc(), diag::err_template_kw_missing)
609 << "" << NameInfo.getName().getAsString() << SourceRange(Less, Greater);
610 return;
611 }
612
613 // Try to correct the name by looking for templates and C++ named casts.
614 struct TemplateCandidateFilter : CorrectionCandidateCallback {
615 Sema &S;
616 TemplateCandidateFilter(Sema &S) : S(S) {
617 WantTypeSpecifiers = false;
618 WantExpressionKeywords = false;
619 WantRemainingKeywords = false;
620 WantCXXNamedCasts = true;
621 };
622 bool ValidateCandidate(const TypoCorrection &Candidate) override {
623 if (auto *ND = Candidate.getCorrectionDecl())
624 return S.getAsTemplateNameDecl(ND);
625 return Candidate.isKeyword();
626 }
627
628 std::unique_ptr<CorrectionCandidateCallback> clone() override {
629 return std::make_unique<TemplateCandidateFilter>(*this);
630 }
631 };
632
633 DeclarationName Name = NameInfo.getName();
634 TemplateCandidateFilter CCC(*this);
635 if (TypoCorrection Corrected = CorrectTypo(NameInfo, LookupKind, S, &SS, CCC,
636 CTK_ErrorRecovery, LookupCtx)) {
637 auto *ND = Corrected.getFoundDecl();
638 if (ND)
639 ND = getAsTemplateNameDecl(ND);
640 if (ND || Corrected.isKeyword()) {
641 if (LookupCtx) {
642 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
643 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
644 Name.getAsString() == CorrectedStr;
645 diagnoseTypo(Corrected,
646 PDiag(diag::err_non_template_in_member_template_id_suggest)
647 << Name << LookupCtx << DroppedSpecifier
648 << SS.getRange(), false);
649 } else {
650 diagnoseTypo(Corrected,
651 PDiag(diag::err_non_template_in_template_id_suggest)
652 << Name, false);
653 }
654 if (Found)
655 Diag(Found->getLocation(),
656 diag::note_non_template_in_template_id_found);
657 return;
658 }
659 }
660
661 Diag(NameInfo.getLoc(), diag::err_non_template_in_template_id)
662 << Name << SourceRange(Less, Greater);
663 if (Found)
664 Diag(Found->getLocation(), diag::note_non_template_in_template_id_found);
665}
666
667/// ActOnDependentIdExpression - Handle a dependent id-expression that
668/// was just parsed. This is only possible with an explicit scope
669/// specifier naming a dependent type.
670ExprResult
671Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
672 SourceLocation TemplateKWLoc,
673 const DeclarationNameInfo &NameInfo,
674 bool isAddressOfOperand,
675 const TemplateArgumentListInfo *TemplateArgs) {
676 DeclContext *DC = getFunctionLevelDeclContext();
677
678 // C++11 [expr.prim.general]p12:
679 // An id-expression that denotes a non-static data member or non-static
680 // member function of a class can only be used:
681 // (...)
682 // - if that id-expression denotes a non-static data member and it
683 // appears in an unevaluated operand.
684 //
685 // If this might be the case, form a DependentScopeDeclRefExpr instead of a
686 // CXXDependentScopeMemberExpr. The former can instantiate to either
687 // DeclRefExpr or MemberExpr depending on lookup results, while the latter is
688 // always a MemberExpr.
689 bool MightBeCxx11UnevalField =
690 getLangOpts().CPlusPlus11 && isUnevaluatedContext();
691
692 // Check if the nested name specifier is an enum type.
693 bool IsEnum = false;
694 if (NestedNameSpecifier *NNS = SS.getScopeRep())
695 IsEnum = dyn_cast_or_null<EnumType>(NNS->getAsType());
696
697 if (!MightBeCxx11UnevalField && !isAddressOfOperand && !IsEnum &&
698 isa<CXXMethodDecl>(DC) && cast<CXXMethodDecl>(DC)->isInstance()) {
699 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType();
700
701 // Since the 'this' expression is synthesized, we don't need to
702 // perform the double-lookup check.
703 NamedDecl *FirstQualifierInScope = nullptr;
704
705 return CXXDependentScopeMemberExpr::Create(
706 Context, /*This*/ nullptr, ThisType, /*IsArrow*/ true,
707 /*Op*/ SourceLocation(), SS.getWithLocInContext(Context), TemplateKWLoc,
708 FirstQualifierInScope, NameInfo, TemplateArgs);
709 }
710
711 return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs);
712}
713
714ExprResult
715Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
716 SourceLocation TemplateKWLoc,
717 const DeclarationNameInfo &NameInfo,
718 const TemplateArgumentListInfo *TemplateArgs) {
719 // DependentScopeDeclRefExpr::Create requires a valid QualifierLoc
720 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
721 if (!QualifierLoc)
722 return ExprError();
723
724 return DependentScopeDeclRefExpr::Create(
725 Context, QualifierLoc, TemplateKWLoc, NameInfo, TemplateArgs);
726}
727
728
729/// Determine whether we would be unable to instantiate this template (because
730/// it either has no definition, or is in the process of being instantiated).
731bool Sema::DiagnoseUninstantiableTemplate(SourceLocation PointOfInstantiation,
732 NamedDecl *Instantiation,
733 bool InstantiatedFromMember,
734 const NamedDecl *Pattern,
735 const NamedDecl *PatternDef,
736 TemplateSpecializationKind TSK,
737 bool Complain /*= true*/) {
738 assert(isa<TagDecl>(Instantiation) || isa<FunctionDecl>(Instantiation) ||((isa<TagDecl>(Instantiation) || isa<FunctionDecl>
(Instantiation) || isa<VarDecl>(Instantiation)) ? static_cast
<void> (0) : __assert_fail ("isa<TagDecl>(Instantiation) || isa<FunctionDecl>(Instantiation) || isa<VarDecl>(Instantiation)"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 739, __PRETTY_FUNCTION__))
739 isa<VarDecl>(Instantiation))((isa<TagDecl>(Instantiation) || isa<FunctionDecl>
(Instantiation) || isa<VarDecl>(Instantiation)) ? static_cast
<void> (0) : __assert_fail ("isa<TagDecl>(Instantiation) || isa<FunctionDecl>(Instantiation) || isa<VarDecl>(Instantiation)"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 739, __PRETTY_FUNCTION__))
;
740
741 bool IsEntityBeingDefined = false;
742 if (const TagDecl *TD = dyn_cast_or_null<TagDecl>(PatternDef))
743 IsEntityBeingDefined = TD->isBeingDefined();
744
745 if (PatternDef && !IsEntityBeingDefined) {
746 NamedDecl *SuggestedDef = nullptr;
747 if (!hasVisibleDefinition(const_cast<NamedDecl*>(PatternDef), &SuggestedDef,
748 /*OnlyNeedComplete*/false)) {
749 // If we're allowed to diagnose this and recover, do so.
750 bool Recover = Complain && !isSFINAEContext();
751 if (Complain)
752 diagnoseMissingImport(PointOfInstantiation, SuggestedDef,
753 Sema::MissingImportKind::Definition, Recover);
754 return !Recover;
755 }
756 return false;
757 }
758
759 if (!Complain || (PatternDef && PatternDef->isInvalidDecl()))
760 return true;
761
762 llvm::Optional<unsigned> Note;
763 QualType InstantiationTy;
764 if (TagDecl *TD = dyn_cast<TagDecl>(Instantiation))
765 InstantiationTy = Context.getTypeDeclType(TD);
766 if (PatternDef) {
767 Diag(PointOfInstantiation,
768 diag::err_template_instantiate_within_definition)
769 << /*implicit|explicit*/(TSK != TSK_ImplicitInstantiation)
770 << InstantiationTy;
771 // Not much point in noting the template declaration here, since
772 // we're lexically inside it.
773 Instantiation->setInvalidDecl();
774 } else if (InstantiatedFromMember) {
775 if (isa<FunctionDecl>(Instantiation)) {
776 Diag(PointOfInstantiation,
777 diag::err_explicit_instantiation_undefined_member)
778 << /*member function*/ 1 << Instantiation->getDeclName()
779 << Instantiation->getDeclContext();
780 Note = diag::note_explicit_instantiation_here;
781 } else {
782 assert(isa<TagDecl>(Instantiation) && "Must be a TagDecl!")((isa<TagDecl>(Instantiation) && "Must be a TagDecl!"
) ? static_cast<void> (0) : __assert_fail ("isa<TagDecl>(Instantiation) && \"Must be a TagDecl!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 782, __PRETTY_FUNCTION__))
;
783 Diag(PointOfInstantiation,
784 diag::err_implicit_instantiate_member_undefined)
785 << InstantiationTy;
786 Note = diag::note_member_declared_at;
787 }
788 } else {
789 if (isa<FunctionDecl>(Instantiation)) {
790 Diag(PointOfInstantiation,
791 diag::err_explicit_instantiation_undefined_func_template)
792 << Pattern;
793 Note = diag::note_explicit_instantiation_here;
794 } else if (isa<TagDecl>(Instantiation)) {
795 Diag(PointOfInstantiation, diag::err_template_instantiate_undefined)
796 << (TSK != TSK_ImplicitInstantiation)
797 << InstantiationTy;
798 Note = diag::note_template_decl_here;
799 } else {
800 assert(isa<VarDecl>(Instantiation) && "Must be a VarDecl!")((isa<VarDecl>(Instantiation) && "Must be a VarDecl!"
) ? static_cast<void> (0) : __assert_fail ("isa<VarDecl>(Instantiation) && \"Must be a VarDecl!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 800, __PRETTY_FUNCTION__))
;
801 if (isa<VarTemplateSpecializationDecl>(Instantiation)) {
802 Diag(PointOfInstantiation,
803 diag::err_explicit_instantiation_undefined_var_template)
804 << Instantiation;
805 Instantiation->setInvalidDecl();
806 } else
807 Diag(PointOfInstantiation,
808 diag::err_explicit_instantiation_undefined_member)
809 << /*static data member*/ 2 << Instantiation->getDeclName()
810 << Instantiation->getDeclContext();
811 Note = diag::note_explicit_instantiation_here;
812 }
813 }
814 if (Note) // Diagnostics were emitted.
815 Diag(Pattern->getLocation(), Note.getValue());
816
817 // In general, Instantiation isn't marked invalid to get more than one
818 // error for multiple undefined instantiations. But the code that does
819 // explicit declaration -> explicit definition conversion can't handle
820 // invalid declarations, so mark as invalid in that case.
821 if (TSK == TSK_ExplicitInstantiationDeclaration)
822 Instantiation->setInvalidDecl();
823 return true;
824}
825
826/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
827/// that the template parameter 'PrevDecl' is being shadowed by a new
828/// declaration at location Loc. Returns true to indicate that this is
829/// an error, and false otherwise.
830void Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
831 assert(PrevDecl->isTemplateParameter() && "Not a template parameter")((PrevDecl->isTemplateParameter() && "Not a template parameter"
) ? static_cast<void> (0) : __assert_fail ("PrevDecl->isTemplateParameter() && \"Not a template parameter\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 831, __PRETTY_FUNCTION__))
;
832
833 // C++ [temp.local]p4:
834 // A template-parameter shall not be redeclared within its
835 // scope (including nested scopes).
836 //
837 // Make this a warning when MSVC compatibility is requested.
838 unsigned DiagId = getLangOpts().MSVCCompat ? diag::ext_template_param_shadow
839 : diag::err_template_param_shadow;
840 Diag(Loc, DiagId) << cast<NamedDecl>(PrevDecl)->getDeclName();
841 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
842}
843
844/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
845/// the parameter D to reference the templated declaration and return a pointer
846/// to the template declaration. Otherwise, do nothing to D and return null.
847TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) {
848 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) {
849 D = Temp->getTemplatedDecl();
850 return Temp;
851 }
852 return nullptr;
853}
854
855ParsedTemplateArgument ParsedTemplateArgument::getTemplatePackExpansion(
856 SourceLocation EllipsisLoc) const {
857 assert(Kind == Template &&((Kind == Template && "Only template template arguments can be pack expansions here"
) ? static_cast<void> (0) : __assert_fail ("Kind == Template && \"Only template template arguments can be pack expansions here\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 858, __PRETTY_FUNCTION__))
858 "Only template template arguments can be pack expansions here")((Kind == Template && "Only template template arguments can be pack expansions here"
) ? static_cast<void> (0) : __assert_fail ("Kind == Template && \"Only template template arguments can be pack expansions here\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 858, __PRETTY_FUNCTION__))
;
859 assert(getAsTemplate().get().containsUnexpandedParameterPack() &&((getAsTemplate().get().containsUnexpandedParameterPack() &&
"Template template argument pack expansion without packs") ?
static_cast<void> (0) : __assert_fail ("getAsTemplate().get().containsUnexpandedParameterPack() && \"Template template argument pack expansion without packs\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 860, __PRETTY_FUNCTION__))
860 "Template template argument pack expansion without packs")((getAsTemplate().get().containsUnexpandedParameterPack() &&
"Template template argument pack expansion without packs") ?
static_cast<void> (0) : __assert_fail ("getAsTemplate().get().containsUnexpandedParameterPack() && \"Template template argument pack expansion without packs\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 860, __PRETTY_FUNCTION__))
;
861 ParsedTemplateArgument Result(*this);
862 Result.EllipsisLoc = EllipsisLoc;
863 return Result;
864}
865
866static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
867 const ParsedTemplateArgument &Arg) {
868
869 switch (Arg.getKind()) {
870 case ParsedTemplateArgument::Type: {
871 TypeSourceInfo *DI;
872 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
873 if (!DI)
874 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
875 return TemplateArgumentLoc(TemplateArgument(T), DI);
876 }
877
878 case ParsedTemplateArgument::NonType: {
879 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
880 return TemplateArgumentLoc(TemplateArgument(E), E);
881 }
882
883 case ParsedTemplateArgument::Template: {
884 TemplateName Template = Arg.getAsTemplate().get();
885 TemplateArgument TArg;
886 if (Arg.getEllipsisLoc().isValid())
887 TArg = TemplateArgument(Template, Optional<unsigned int>());
888 else
889 TArg = Template;
890 return TemplateArgumentLoc(TArg,
891 Arg.getScopeSpec().getWithLocInContext(
892 SemaRef.Context),
893 Arg.getLocation(),
894 Arg.getEllipsisLoc());
895 }
896 }
897
898 llvm_unreachable("Unhandled parsed template argument")::llvm::llvm_unreachable_internal("Unhandled parsed template argument"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 898)
;
899}
900
901/// Translates template arguments as provided by the parser
902/// into template arguments used by semantic analysis.
903void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
904 TemplateArgumentListInfo &TemplateArgs) {
905 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
906 TemplateArgs.addArgument(translateTemplateArgument(*this,
907 TemplateArgsIn[I]));
908}
909
910static void maybeDiagnoseTemplateParameterShadow(Sema &SemaRef, Scope *S,
911 SourceLocation Loc,
912 IdentifierInfo *Name) {
913 NamedDecl *PrevDecl = SemaRef.LookupSingleName(
914 S, Name, Loc, Sema::LookupOrdinaryName, Sema::ForVisibleRedeclaration);
915 if (PrevDecl && PrevDecl->isTemplateParameter())
916 SemaRef.DiagnoseTemplateParameterShadow(Loc, PrevDecl);
917}
918
919/// Convert a parsed type into a parsed template argument. This is mostly
920/// trivial, except that we may have parsed a C++17 deduced class template
921/// specialization type, in which case we should form a template template
922/// argument instead of a type template argument.
923ParsedTemplateArgument Sema::ActOnTemplateTypeArgument(TypeResult ParsedType) {
924 TypeSourceInfo *TInfo;
925 QualType T = GetTypeFromParser(ParsedType.get(), &TInfo);
926 if (T.isNull())
927 return ParsedTemplateArgument();
928 assert(TInfo && "template argument with no location")((TInfo && "template argument with no location") ? static_cast
<void> (0) : __assert_fail ("TInfo && \"template argument with no location\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 928, __PRETTY_FUNCTION__))
;
929
930 // If we might have formed a deduced template specialization type, convert
931 // it to a template template argument.
932 if (getLangOpts().CPlusPlus17) {
933 TypeLoc TL = TInfo->getTypeLoc();
934 SourceLocation EllipsisLoc;
935 if (auto PET = TL.getAs<PackExpansionTypeLoc>()) {
936 EllipsisLoc = PET.getEllipsisLoc();
937 TL = PET.getPatternLoc();
938 }
939
940 CXXScopeSpec SS;
941 if (auto ET = TL.getAs<ElaboratedTypeLoc>()) {
942 SS.Adopt(ET.getQualifierLoc());
943 TL = ET.getNamedTypeLoc();
944 }
945
946 if (auto DTST = TL.getAs<DeducedTemplateSpecializationTypeLoc>()) {
947 TemplateName Name = DTST.getTypePtr()->getTemplateName();
948 if (SS.isSet())
949 Name = Context.getQualifiedTemplateName(SS.getScopeRep(),
950 /*HasTemplateKeyword*/ false,
951 Name.getAsTemplateDecl());
952 ParsedTemplateArgument Result(SS, TemplateTy::make(Name),
953 DTST.getTemplateNameLoc());
954 if (EllipsisLoc.isValid())
955 Result = Result.getTemplatePackExpansion(EllipsisLoc);
956 return Result;
957 }
958 }
959
960 // This is a normal type template argument. Note, if the type template
961 // argument is an injected-class-name for a template, it has a dual nature
962 // and can be used as either a type or a template. We handle that in
963 // convertTypeTemplateArgumentToTemplate.
964 return ParsedTemplateArgument(ParsedTemplateArgument::Type,
965 ParsedType.get().getAsOpaquePtr(),
966 TInfo->getTypeLoc().getBeginLoc());
967}
968
969/// ActOnTypeParameter - Called when a C++ template type parameter
970/// (e.g., "typename T") has been parsed. Typename specifies whether
971/// the keyword "typename" was used to declare the type parameter
972/// (otherwise, "class" was used), and KeyLoc is the location of the
973/// "class" or "typename" keyword. ParamName is the name of the
974/// parameter (NULL indicates an unnamed template parameter) and
975/// ParamNameLoc is the location of the parameter name (if any).
976/// If the type parameter has a default argument, it will be added
977/// later via ActOnTypeParameterDefault.
978NamedDecl *Sema::ActOnTypeParameter(Scope *S, bool Typename,
979 SourceLocation EllipsisLoc,
980 SourceLocation KeyLoc,
981 IdentifierInfo *ParamName,
982 SourceLocation ParamNameLoc,
983 unsigned Depth, unsigned Position,
984 SourceLocation EqualLoc,
985 ParsedType DefaultArg) {
986 assert(S->isTemplateParamScope() &&((S->isTemplateParamScope() && "Template type parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Template type parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 987, __PRETTY_FUNCTION__))
987 "Template type parameter not in template parameter scope!")((S->isTemplateParamScope() && "Template type parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Template type parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 987, __PRETTY_FUNCTION__))
;
988
989 bool IsParameterPack = EllipsisLoc.isValid();
990 TemplateTypeParmDecl *Param = TemplateTypeParmDecl::Create(
991 Context, Context.getTranslationUnitDecl(), KeyLoc, ParamNameLoc, Depth,
992 Position, ParamName, Typename, IsParameterPack);
993 Param->setAccess(AS_public);
994
995 if (Param->isParameterPack())
996 if (auto *LSI = getEnclosingLambda())
997 LSI->LocalPacks.push_back(Param);
998
999 if (ParamName) {
1000 maybeDiagnoseTemplateParameterShadow(*this, S, ParamNameLoc, ParamName);
1001
1002 // Add the template parameter into the current scope.
1003 S->AddDecl(Param);
1004 IdResolver.AddDecl(Param);
1005 }
1006
1007 // C++0x [temp.param]p9:
1008 // A default template-argument may be specified for any kind of
1009 // template-parameter that is not a template parameter pack.
1010 if (DefaultArg && IsParameterPack) {
1011 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
1012 DefaultArg = nullptr;
1013 }
1014
1015 // Handle the default argument, if provided.
1016 if (DefaultArg) {
1017 TypeSourceInfo *DefaultTInfo;
1018 GetTypeFromParser(DefaultArg, &DefaultTInfo);
1019
1020 assert(DefaultTInfo && "expected source information for type")((DefaultTInfo && "expected source information for type"
) ? static_cast<void> (0) : __assert_fail ("DefaultTInfo && \"expected source information for type\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1020, __PRETTY_FUNCTION__))
;
1021
1022 // Check for unexpanded parameter packs.
1023 if (DiagnoseUnexpandedParameterPack(ParamNameLoc, DefaultTInfo,
1024 UPPC_DefaultArgument))
1025 return Param;
1026
1027 // Check the template argument itself.
1028 if (CheckTemplateArgument(Param, DefaultTInfo)) {
1029 Param->setInvalidDecl();
1030 return Param;
1031 }
1032
1033 Param->setDefaultArgument(DefaultTInfo);
1034 }
1035
1036 return Param;
1037}
1038
1039/// Check that the type of a non-type template parameter is
1040/// well-formed.
1041///
1042/// \returns the (possibly-promoted) parameter type if valid;
1043/// otherwise, produces a diagnostic and returns a NULL type.
1044QualType Sema::CheckNonTypeTemplateParameterType(TypeSourceInfo *&TSI,
1045 SourceLocation Loc) {
1046 if (TSI->getType()->isUndeducedType()) {
1047 // C++17 [temp.dep.expr]p3:
1048 // An id-expression is type-dependent if it contains
1049 // - an identifier associated by name lookup with a non-type
1050 // template-parameter declared with a type that contains a
1051 // placeholder type (7.1.7.4),
1052 TSI = SubstAutoTypeSourceInfo(TSI, Context.DependentTy);
1053 }
1054
1055 return CheckNonTypeTemplateParameterType(TSI->getType(), Loc);
1056}
1057
1058QualType Sema::CheckNonTypeTemplateParameterType(QualType T,
1059 SourceLocation Loc) {
1060 // We don't allow variably-modified types as the type of non-type template
1061 // parameters.
1062 if (T->isVariablyModifiedType()) {
1063 Diag(Loc, diag::err_variably_modified_nontype_template_param)
1064 << T;
1065 return QualType();
1066 }
1067
1068 // C++ [temp.param]p4:
1069 //
1070 // A non-type template-parameter shall have one of the following
1071 // (optionally cv-qualified) types:
1072 //
1073 // -- integral or enumeration type,
1074 if (T->isIntegralOrEnumerationType() ||
1075 // -- pointer to object or pointer to function,
1076 T->isPointerType() ||
1077 // -- reference to object or reference to function,
1078 T->isReferenceType() ||
1079 // -- pointer to member,
1080 T->isMemberPointerType() ||
1081 // -- std::nullptr_t.
1082 T->isNullPtrType() ||
1083 // Allow use of auto in template parameter declarations.
1084 T->isUndeducedType()) {
1085 // C++ [temp.param]p5: The top-level cv-qualifiers on the template-parameter
1086 // are ignored when determining its type.
1087 return T.getUnqualifiedType();
1088 }
1089
1090 // C++ [temp.param]p8:
1091 //
1092 // A non-type template-parameter of type "array of T" or
1093 // "function returning T" is adjusted to be of type "pointer to
1094 // T" or "pointer to function returning T", respectively.
1095 if (T->isArrayType() || T->isFunctionType())
1096 return Context.getDecayedType(T);
1097
1098 // If T is a dependent type, we can't do the check now, so we
1099 // assume that it is well-formed. Note that stripping off the
1100 // qualifiers here is not really correct if T turns out to be
1101 // an array type, but we'll recompute the type everywhere it's
1102 // used during instantiation, so that should be OK. (Using the
1103 // qualified type is equally wrong.)
1104 if (T->isDependentType())
1105 return T.getUnqualifiedType();
1106
1107 Diag(Loc, diag::err_template_nontype_parm_bad_type)
1108 << T;
1109
1110 return QualType();
1111}
1112
1113NamedDecl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
1114 unsigned Depth,
1115 unsigned Position,
1116 SourceLocation EqualLoc,
1117 Expr *Default) {
1118 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
1119
1120 // Check that we have valid decl-specifiers specified.
1121 auto CheckValidDeclSpecifiers = [this, &D] {
1122 // C++ [temp.param]
1123 // p1
1124 // template-parameter:
1125 // ...
1126 // parameter-declaration
1127 // p2
1128 // ... A storage class shall not be specified in a template-parameter
1129 // declaration.
1130 // [dcl.typedef]p1:
1131 // The typedef specifier [...] shall not be used in the decl-specifier-seq
1132 // of a parameter-declaration
1133 const DeclSpec &DS = D.getDeclSpec();
1134 auto EmitDiag = [this](SourceLocation Loc) {
1135 Diag(Loc, diag::err_invalid_decl_specifier_in_nontype_parm)
1136 << FixItHint::CreateRemoval(Loc);
1137 };
1138 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified)
1139 EmitDiag(DS.getStorageClassSpecLoc());
1140
1141 if (DS.getThreadStorageClassSpec() != TSCS_unspecified)
1142 EmitDiag(DS.getThreadStorageClassSpecLoc());
1143
1144 // [dcl.inline]p1:
1145 // The inline specifier can be applied only to the declaration or
1146 // definition of a variable or function.
1147
1148 if (DS.isInlineSpecified())
1149 EmitDiag(DS.getInlineSpecLoc());
1150
1151 // [dcl.constexpr]p1:
1152 // The constexpr specifier shall be applied only to the definition of a
1153 // variable or variable template or the declaration of a function or
1154 // function template.
1155
1156 if (DS.hasConstexprSpecifier())
1157 EmitDiag(DS.getConstexprSpecLoc());
1158
1159 // [dcl.fct.spec]p1:
1160 // Function-specifiers can be used only in function declarations.
1161
1162 if (DS.isVirtualSpecified())
1163 EmitDiag(DS.getVirtualSpecLoc());
1164
1165 if (DS.hasExplicitSpecifier())
1166 EmitDiag(DS.getExplicitSpecLoc());
1167
1168 if (DS.isNoreturnSpecified())
1169 EmitDiag(DS.getNoreturnSpecLoc());
1170 };
1171
1172 CheckValidDeclSpecifiers();
1173
1174 if (TInfo->getType()->isUndeducedType()) {
1175 Diag(D.getIdentifierLoc(),
1176 diag::warn_cxx14_compat_template_nontype_parm_auto_type)
1177 << QualType(TInfo->getType()->getContainedAutoType(), 0);
1178 }
1179
1180 assert(S->isTemplateParamScope() &&((S->isTemplateParamScope() && "Non-type template parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Non-type template parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1181, __PRETTY_FUNCTION__))
1181 "Non-type template parameter not in template parameter scope!")((S->isTemplateParamScope() && "Non-type template parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Non-type template parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1181, __PRETTY_FUNCTION__))
;
1182 bool Invalid = false;
1183
1184 QualType T = CheckNonTypeTemplateParameterType(TInfo, D.getIdentifierLoc());
1185 if (T.isNull()) {
1186 T = Context.IntTy; // Recover with an 'int' type.
1187 Invalid = true;
1188 }
1189
1190 CheckFunctionOrTemplateParamDeclarator(S, D);
1191
1192 IdentifierInfo *ParamName = D.getIdentifier();
1193 bool IsParameterPack = D.hasEllipsis();
1194 NonTypeTemplateParmDecl *Param = NonTypeTemplateParmDecl::Create(
1195 Context, Context.getTranslationUnitDecl(), D.getBeginLoc(),
1196 D.getIdentifierLoc(), Depth, Position, ParamName, T, IsParameterPack,
1197 TInfo);
1198 Param->setAccess(AS_public);
1199
1200 if (Invalid)
1201 Param->setInvalidDecl();
1202
1203 if (Param->isParameterPack())
1204 if (auto *LSI = getEnclosingLambda())
1205 LSI->LocalPacks.push_back(Param);
1206
1207 if (ParamName) {
1208 maybeDiagnoseTemplateParameterShadow(*this, S, D.getIdentifierLoc(),
1209 ParamName);
1210
1211 // Add the template parameter into the current scope.
1212 S->AddDecl(Param);
1213 IdResolver.AddDecl(Param);
1214 }
1215
1216 // C++0x [temp.param]p9:
1217 // A default template-argument may be specified for any kind of
1218 // template-parameter that is not a template parameter pack.
1219 if (Default && IsParameterPack) {
1220 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
1221 Default = nullptr;
1222 }
1223
1224 // Check the well-formedness of the default template argument, if provided.
1225 if (Default) {
1226 // Check for unexpanded parameter packs.
1227 if (DiagnoseUnexpandedParameterPack(Default, UPPC_DefaultArgument))
1228 return Param;
1229
1230 TemplateArgument Converted;
1231 ExprResult DefaultRes =
1232 CheckTemplateArgument(Param, Param->getType(), Default, Converted);
1233 if (DefaultRes.isInvalid()) {
1234 Param->setInvalidDecl();
1235 return Param;
1236 }
1237 Default = DefaultRes.get();
1238
1239 Param->setDefaultArgument(Default);
1240 }
1241
1242 return Param;
1243}
1244
1245/// ActOnTemplateTemplateParameter - Called when a C++ template template
1246/// parameter (e.g. T in template <template \<typename> class T> class array)
1247/// has been parsed. S is the current scope.
1248NamedDecl *Sema::ActOnTemplateTemplateParameter(Scope* S,
1249 SourceLocation TmpLoc,
1250 TemplateParameterList *Params,
1251 SourceLocation EllipsisLoc,
1252 IdentifierInfo *Name,
1253 SourceLocation NameLoc,
1254 unsigned Depth,
1255 unsigned Position,
1256 SourceLocation EqualLoc,
1257 ParsedTemplateArgument Default) {
1258 assert(S->isTemplateParamScope() &&((S->isTemplateParamScope() && "Template template parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Template template parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1259, __PRETTY_FUNCTION__))
1259 "Template template parameter not in template parameter scope!")((S->isTemplateParamScope() && "Template template parameter not in template parameter scope!"
) ? static_cast<void> (0) : __assert_fail ("S->isTemplateParamScope() && \"Template template parameter not in template parameter scope!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1259, __PRETTY_FUNCTION__))
;
1260
1261 // Construct the parameter object.
1262 bool IsParameterPack = EllipsisLoc.isValid();
1263 TemplateTemplateParmDecl *Param =
1264 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
1265 NameLoc.isInvalid()? TmpLoc : NameLoc,
1266 Depth, Position, IsParameterPack,
1267 Name, Params);
1268 Param->setAccess(AS_public);
1269
1270 if (Param->isParameterPack())
1271 if (auto *LSI = getEnclosingLambda())
1272 LSI->LocalPacks.push_back(Param);
1273
1274 // If the template template parameter has a name, then link the identifier
1275 // into the scope and lookup mechanisms.
1276 if (Name) {
1277 maybeDiagnoseTemplateParameterShadow(*this, S, NameLoc, Name);
1278
1279 S->AddDecl(Param);
1280 IdResolver.AddDecl(Param);
1281 }
1282
1283 if (Params->size() == 0) {
1284 Diag(Param->getLocation(), diag::err_template_template_parm_no_parms)
1285 << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc());
1286 Param->setInvalidDecl();
1287 }
1288
1289 // C++0x [temp.param]p9:
1290 // A default template-argument may be specified for any kind of
1291 // template-parameter that is not a template parameter pack.
1292 if (IsParameterPack && !Default.isInvalid()) {
1293 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
1294 Default = ParsedTemplateArgument();
1295 }
1296
1297 if (!Default.isInvalid()) {
1298 // Check only that we have a template template argument. We don't want to
1299 // try to check well-formedness now, because our template template parameter
1300 // might have dependent types in its template parameters, which we wouldn't
1301 // be able to match now.
1302 //
1303 // If none of the template template parameter's template arguments mention
1304 // other template parameters, we could actually perform more checking here.
1305 // However, it isn't worth doing.
1306 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
1307 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
1308 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_valid_template)
1309 << DefaultArg.getSourceRange();
1310 return Param;
1311 }
1312
1313 // Check for unexpanded parameter packs.
1314 if (DiagnoseUnexpandedParameterPack(DefaultArg.getLocation(),
1315 DefaultArg.getArgument().getAsTemplate(),
1316 UPPC_DefaultArgument))
1317 return Param;
1318
1319 Param->setDefaultArgument(Context, DefaultArg);
1320 }
1321
1322 return Param;
1323}
1324
1325/// ActOnTemplateParameterList - Builds a TemplateParameterList, optionally
1326/// constrained by RequiresClause, that contains the template parameters in
1327/// Params.
1328TemplateParameterList *
1329Sema::ActOnTemplateParameterList(unsigned Depth,
1330 SourceLocation ExportLoc,
1331 SourceLocation TemplateLoc,
1332 SourceLocation LAngleLoc,
1333 ArrayRef<NamedDecl *> Params,
1334 SourceLocation RAngleLoc,
1335 Expr *RequiresClause) {
1336 if (ExportLoc.isValid())
1337 Diag(ExportLoc, diag::warn_template_export_unsupported);
1338
1339 return TemplateParameterList::Create(
1340 Context, TemplateLoc, LAngleLoc,
1341 llvm::makeArrayRef(Params.data(), Params.size()),
1342 RAngleLoc, RequiresClause);
1343}
1344
1345static void SetNestedNameSpecifier(Sema &S, TagDecl *T,
1346 const CXXScopeSpec &SS) {
1347 if (SS.isSet())
1348 T->setQualifierInfo(SS.getWithLocInContext(S.Context));
1349}
1350
1351DeclResult Sema::CheckClassTemplate(
1352 Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc,
1353 CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc,
1354 const ParsedAttributesView &Attr, TemplateParameterList *TemplateParams,
1355 AccessSpecifier AS, SourceLocation ModulePrivateLoc,
1356 SourceLocation FriendLoc, unsigned NumOuterTemplateParamLists,
1357 TemplateParameterList **OuterTemplateParamLists, SkipBodyInfo *SkipBody) {
1358 assert(TemplateParams && TemplateParams->size() > 0 &&((TemplateParams && TemplateParams->size() > 0 &&
"No template parameters") ? static_cast<void> (0) : __assert_fail
("TemplateParams && TemplateParams->size() > 0 && \"No template parameters\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1359, __PRETTY_FUNCTION__))
1359 "No template parameters")((TemplateParams && TemplateParams->size() > 0 &&
"No template parameters") ? static_cast<void> (0) : __assert_fail
("TemplateParams && TemplateParams->size() > 0 && \"No template parameters\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1359, __PRETTY_FUNCTION__))
;
1360 assert(TUK != TUK_Reference && "Can only declare or define class templates")((TUK != TUK_Reference && "Can only declare or define class templates"
) ? static_cast<void> (0) : __assert_fail ("TUK != TUK_Reference && \"Can only declare or define class templates\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1360, __PRETTY_FUNCTION__))
;
1361 bool Invalid = false;
1362
1363 // Check that we can declare a template here.
1364 if (CheckTemplateDeclScope(S, TemplateParams))
1365 return true;
1366
1367 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
1368 assert(Kind != TTK_Enum && "can't build template of enumerated type")((Kind != TTK_Enum && "can't build template of enumerated type"
) ? static_cast<void> (0) : __assert_fail ("Kind != TTK_Enum && \"can't build template of enumerated type\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1368, __PRETTY_FUNCTION__))
;
1369
1370 // There is no such thing as an unnamed class template.
1371 if (!Name) {
1372 Diag(KWLoc, diag::err_template_unnamed_class);
1373 return true;
1374 }
1375
1376 // Find any previous declaration with this name. For a friend with no
1377 // scope explicitly specified, we only look for tag declarations (per
1378 // C++11 [basic.lookup.elab]p2).
1379 DeclContext *SemanticContext;
1380 LookupResult Previous(*this, Name, NameLoc,
1381 (SS.isEmpty() && TUK == TUK_Friend)
1382 ? LookupTagName : LookupOrdinaryName,
1383 forRedeclarationInCurContext());
1384 if (SS.isNotEmpty() && !SS.isInvalid()) {
1385 SemanticContext = computeDeclContext(SS, true);
1386 if (!SemanticContext) {
1387 // FIXME: Horrible, horrible hack! We can't currently represent this
1388 // in the AST, and historically we have just ignored such friend
1389 // class templates, so don't complain here.
1390 Diag(NameLoc, TUK == TUK_Friend
1391 ? diag::warn_template_qualified_friend_ignored
1392 : diag::err_template_qualified_declarator_no_match)
1393 << SS.getScopeRep() << SS.getRange();
1394 return TUK != TUK_Friend;
1395 }
1396
1397 if (RequireCompleteDeclContext(SS, SemanticContext))
1398 return true;
1399
1400 // If we're adding a template to a dependent context, we may need to
1401 // rebuilding some of the types used within the template parameter list,
1402 // now that we know what the current instantiation is.
1403 if (SemanticContext->isDependentContext()) {
1404 ContextRAII SavedContext(*this, SemanticContext);
1405 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
1406 Invalid = true;
1407 } else if (TUK != TUK_Friend && TUK != TUK_Reference)
1408 diagnoseQualifiedDeclaration(SS, SemanticContext, Name, NameLoc, false);
1409
1410 LookupQualifiedName(Previous, SemanticContext);
1411 } else {
1412 SemanticContext = CurContext;
1413
1414 // C++14 [class.mem]p14:
1415 // If T is the name of a class, then each of the following shall have a
1416 // name different from T:
1417 // -- every member template of class T
1418 if (TUK != TUK_Friend &&
1419 DiagnoseClassNameShadow(SemanticContext,
1420 DeclarationNameInfo(Name, NameLoc)))
1421 return true;
1422
1423 LookupName(Previous, S);
1424 }
1425
1426 if (Previous.isAmbiguous())
1427 return true;
1428
1429 NamedDecl *PrevDecl = nullptr;
1430 if (Previous.begin() != Previous.end())
1431 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
1432
1433 if (PrevDecl && PrevDecl->isTemplateParameter()) {
1434 // Maybe we will complain about the shadowed template parameter.
1435 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
1436 // Just pretend that we didn't see the previous declaration.
1437 PrevDecl = nullptr;
1438 }
1439
1440 // If there is a previous declaration with the same name, check
1441 // whether this is a valid redeclaration.
1442 ClassTemplateDecl *PrevClassTemplate =
1443 dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
1444
1445 // We may have found the injected-class-name of a class template,
1446 // class template partial specialization, or class template specialization.
1447 // In these cases, grab the template that is being defined or specialized.
1448 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
1449 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
1450 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
1451 PrevClassTemplate
1452 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
1453 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
1454 PrevClassTemplate
1455 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
1456 ->getSpecializedTemplate();
1457 }
1458 }
1459
1460 if (TUK == TUK_Friend) {
1461 // C++ [namespace.memdef]p3:
1462 // [...] When looking for a prior declaration of a class or a function
1463 // declared as a friend, and when the name of the friend class or
1464 // function is neither a qualified name nor a template-id, scopes outside
1465 // the innermost enclosing namespace scope are not considered.
1466 if (!SS.isSet()) {
1467 DeclContext *OutermostContext = CurContext;
1468 while (!OutermostContext->isFileContext())
1469 OutermostContext = OutermostContext->getLookupParent();
1470
1471 if (PrevDecl &&
1472 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
1473 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
1474 SemanticContext = PrevDecl->getDeclContext();
1475 } else {
1476 // Declarations in outer scopes don't matter. However, the outermost
1477 // context we computed is the semantic context for our new
1478 // declaration.
1479 PrevDecl = PrevClassTemplate = nullptr;
1480 SemanticContext = OutermostContext;
1481
1482 // Check that the chosen semantic context doesn't already contain a
1483 // declaration of this name as a non-tag type.
1484 Previous.clear(LookupOrdinaryName);
1485 DeclContext *LookupContext = SemanticContext;
1486 while (LookupContext->isTransparentContext())
1487 LookupContext = LookupContext->getLookupParent();
1488 LookupQualifiedName(Previous, LookupContext);
1489
1490 if (Previous.isAmbiguous())
1491 return true;
1492
1493 if (Previous.begin() != Previous.end())
1494 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
1495 }
1496 }
1497 } else if (PrevDecl &&
1498 !isDeclInScope(Previous.getRepresentativeDecl(), SemanticContext,
1499 S, SS.isValid()))
1500 PrevDecl = PrevClassTemplate = nullptr;
1501
1502 if (auto *Shadow = dyn_cast_or_null<UsingShadowDecl>(
1503 PrevDecl ? Previous.getRepresentativeDecl() : nullptr)) {
1504 if (SS.isEmpty() &&
1505 !(PrevClassTemplate &&
1506 PrevClassTemplate->getDeclContext()->getRedeclContext()->Equals(
1507 SemanticContext->getRedeclContext()))) {
1508 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
1509 Diag(Shadow->getTargetDecl()->getLocation(),
1510 diag::note_using_decl_target);
1511 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
1512 // Recover by ignoring the old declaration.
1513 PrevDecl = PrevClassTemplate = nullptr;
1514 }
1515 }
1516
1517 if (PrevClassTemplate) {
1518 // Ensure that the template parameter lists are compatible. Skip this check
1519 // for a friend in a dependent context: the template parameter list itself
1520 // could be dependent.
1521 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
1522 !TemplateParameterListsAreEqual(TemplateParams,
1523 PrevClassTemplate->getTemplateParameters(),
1524 /*Complain=*/true,
1525 TPL_TemplateMatch))
1526 return true;
1527
1528 // C++ [temp.class]p4:
1529 // In a redeclaration, partial specialization, explicit
1530 // specialization or explicit instantiation of a class template,
1531 // the class-key shall agree in kind with the original class
1532 // template declaration (7.1.5.3).
1533 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
1534 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind,
1535 TUK == TUK_Definition, KWLoc, Name)) {
1536 Diag(KWLoc, diag::err_use_with_wrong_tag)
1537 << Name
1538 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
1539 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
1540 Kind = PrevRecordDecl->getTagKind();
1541 }
1542
1543 // Check for redefinition of this class template.
1544 if (TUK == TUK_Definition) {
1545 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
1546 // If we have a prior definition that is not visible, treat this as
1547 // simply making that previous definition visible.
1548 NamedDecl *Hidden = nullptr;
1549 if (SkipBody && !hasVisibleDefinition(Def, &Hidden)) {
1550 SkipBody->ShouldSkip = true;
1551 SkipBody->Previous = Def;
1552 auto *Tmpl = cast<CXXRecordDecl>(Hidden)->getDescribedClassTemplate();
1553 assert(Tmpl && "original definition of a class template is not a "((Tmpl && "original definition of a class template is not a "
"class template?") ? static_cast<void> (0) : __assert_fail
("Tmpl && \"original definition of a class template is not a \" \"class template?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1554, __PRETTY_FUNCTION__))
1554 "class template?")((Tmpl && "original definition of a class template is not a "
"class template?") ? static_cast<void> (0) : __assert_fail
("Tmpl && \"original definition of a class template is not a \" \"class template?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1554, __PRETTY_FUNCTION__))
;
1555 makeMergedDefinitionVisible(Hidden);
1556 makeMergedDefinitionVisible(Tmpl);
1557 } else {
1558 Diag(NameLoc, diag::err_redefinition) << Name;
1559 Diag(Def->getLocation(), diag::note_previous_definition);
1560 // FIXME: Would it make sense to try to "forget" the previous
1561 // definition, as part of error recovery?
1562 return true;
1563 }
1564 }
1565 }
1566 } else if (PrevDecl) {
1567 // C++ [temp]p5:
1568 // A class template shall not have the same name as any other
1569 // template, class, function, object, enumeration, enumerator,
1570 // namespace, or type in the same scope (3.3), except as specified
1571 // in (14.5.4).
1572 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
1573 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1574 return true;
1575 }
1576
1577 // Check the template parameter list of this declaration, possibly
1578 // merging in the template parameter list from the previous class
1579 // template declaration. Skip this check for a friend in a dependent
1580 // context, because the template parameter list might be dependent.
1581 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
1582 CheckTemplateParameterList(
1583 TemplateParams,
1584 PrevClassTemplate
1585 ? PrevClassTemplate->getMostRecentDecl()->getTemplateParameters()
1586 : nullptr,
1587 (SS.isSet() && SemanticContext && SemanticContext->isRecord() &&
1588 SemanticContext->isDependentContext())
1589 ? TPC_ClassTemplateMember
1590 : TUK == TUK_Friend ? TPC_FriendClassTemplate : TPC_ClassTemplate,
1591 SkipBody))
1592 Invalid = true;
1593
1594 if (SS.isSet()) {
1595 // If the name of the template was qualified, we must be defining the
1596 // template out-of-line.
1597 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate) {
1598 Diag(NameLoc, TUK == TUK_Friend ? diag::err_friend_decl_does_not_match
1599 : diag::err_member_decl_does_not_match)
1600 << Name << SemanticContext << /*IsDefinition*/true << SS.getRange();
1601 Invalid = true;
1602 }
1603 }
1604
1605 // If this is a templated friend in a dependent context we should not put it
1606 // on the redecl chain. In some cases, the templated friend can be the most
1607 // recent declaration tricking the template instantiator to make substitutions
1608 // there.
1609 // FIXME: Figure out how to combine with shouldLinkDependentDeclWithPrevious
1610 bool ShouldAddRedecl
1611 = !(TUK == TUK_Friend && CurContext->isDependentContext());
1612
1613 CXXRecordDecl *NewClass =
1614 CXXRecordDecl::Create(Context, Kind, SemanticContext, KWLoc, NameLoc, Name,
1615 PrevClassTemplate && ShouldAddRedecl ?
1616 PrevClassTemplate->getTemplatedDecl() : nullptr,
1617 /*DelayTypeCreation=*/true);
1618 SetNestedNameSpecifier(*this, NewClass, SS);
1619 if (NumOuterTemplateParamLists > 0)
1620 NewClass->setTemplateParameterListsInfo(
1621 Context, llvm::makeArrayRef(OuterTemplateParamLists,
1622 NumOuterTemplateParamLists));
1623
1624 // Add alignment attributes if necessary; these attributes are checked when
1625 // the ASTContext lays out the structure.
1626 if (TUK == TUK_Definition && (!SkipBody || !SkipBody->ShouldSkip)) {
1627 AddAlignmentAttributesForRecord(NewClass);
1628 AddMsStructLayoutForRecord(NewClass);
1629 }
1630
1631 ClassTemplateDecl *NewTemplate
1632 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
1633 DeclarationName(Name), TemplateParams,
1634 NewClass);
1635
1636 if (ShouldAddRedecl)
1637 NewTemplate->setPreviousDecl(PrevClassTemplate);
1638
1639 NewClass->setDescribedClassTemplate(NewTemplate);
1640
1641 if (ModulePrivateLoc.isValid())
1642 NewTemplate->setModulePrivate();
1643
1644 // Build the type for the class template declaration now.
1645 QualType T = NewTemplate->getInjectedClassNameSpecialization();
1646 T = Context.getInjectedClassNameType(NewClass, T);
1647 assert(T->isDependentType() && "Class template type is not dependent?")((T->isDependentType() && "Class template type is not dependent?"
) ? static_cast<void> (0) : __assert_fail ("T->isDependentType() && \"Class template type is not dependent?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1647, __PRETTY_FUNCTION__))
;
1648 (void)T;
1649
1650 // If we are providing an explicit specialization of a member that is a
1651 // class template, make a note of that.
1652 if (PrevClassTemplate &&
1653 PrevClassTemplate->getInstantiatedFromMemberTemplate())
1654 PrevClassTemplate->setMemberSpecialization();
1655
1656 // Set the access specifier.
1657 if (!Invalid && TUK != TUK_Friend && NewTemplate->getDeclContext()->isRecord())
1658 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
1659
1660 // Set the lexical context of these templates
1661 NewClass->setLexicalDeclContext(CurContext);
1662 NewTemplate->setLexicalDeclContext(CurContext);
1663
1664 if (TUK == TUK_Definition && (!SkipBody || !SkipBody->ShouldSkip))
1665 NewClass->startDefinition();
1666
1667 ProcessDeclAttributeList(S, NewClass, Attr);
1668
1669 if (PrevClassTemplate)
1670 mergeDeclAttributes(NewClass, PrevClassTemplate->getTemplatedDecl());
1671
1672 AddPushedVisibilityAttribute(NewClass);
1673 inferGslOwnerPointerAttribute(NewClass);
1674
1675 if (TUK != TUK_Friend) {
1676 // Per C++ [basic.scope.temp]p2, skip the template parameter scopes.
1677 Scope *Outer = S;
1678 while ((Outer->getFlags() & Scope::TemplateParamScope) != 0)
1679 Outer = Outer->getParent();
1680 PushOnScopeChains(NewTemplate, Outer);
1681 } else {
1682 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
1683 NewTemplate->setAccess(PrevClassTemplate->getAccess());
1684 NewClass->setAccess(PrevClassTemplate->getAccess());
1685 }
1686
1687 NewTemplate->setObjectOfFriendDecl();
1688
1689 // Friend templates are visible in fairly strange ways.
1690 if (!CurContext->isDependentContext()) {
1691 DeclContext *DC = SemanticContext->getRedeclContext();
1692 DC->makeDeclVisibleInContext(NewTemplate);
1693 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
1694 PushOnScopeChains(NewTemplate, EnclosingScope,
1695 /* AddToContext = */ false);
1696 }
1697
1698 FriendDecl *Friend = FriendDecl::Create(
1699 Context, CurContext, NewClass->getLocation(), NewTemplate, FriendLoc);
1700 Friend->setAccess(AS_public);
1701 CurContext->addDecl(Friend);
1702 }
1703
1704 if (PrevClassTemplate)
1705 CheckRedeclarationModuleOwnership(NewTemplate, PrevClassTemplate);
1706
1707 if (Invalid) {
1708 NewTemplate->setInvalidDecl();
1709 NewClass->setInvalidDecl();
1710 }
1711
1712 ActOnDocumentableDecl(NewTemplate);
1713
1714 if (SkipBody && SkipBody->ShouldSkip)
1715 return SkipBody->Previous;
1716
1717 return NewTemplate;
1718}
1719
1720namespace {
1721/// Tree transform to "extract" a transformed type from a class template's
1722/// constructor to a deduction guide.
1723class ExtractTypeForDeductionGuide
1724 : public TreeTransform<ExtractTypeForDeductionGuide> {
1725public:
1726 typedef TreeTransform<ExtractTypeForDeductionGuide> Base;
1727 ExtractTypeForDeductionGuide(Sema &SemaRef) : Base(SemaRef) {}
1728
1729 TypeSourceInfo *transform(TypeSourceInfo *TSI) { return TransformType(TSI); }
1730
1731 QualType TransformTypedefType(TypeLocBuilder &TLB, TypedefTypeLoc TL) {
1732 return TransformType(
1733 TLB,
1734 TL.getTypedefNameDecl()->getTypeSourceInfo()->getTypeLoc());
1735 }
1736};
1737
1738/// Transform to convert portions of a constructor declaration into the
1739/// corresponding deduction guide, per C++1z [over.match.class.deduct]p1.
1740struct ConvertConstructorToDeductionGuideTransform {
1741 ConvertConstructorToDeductionGuideTransform(Sema &S,
1742 ClassTemplateDecl *Template)
1743 : SemaRef(S), Template(Template) {}
1744
1745 Sema &SemaRef;
1746 ClassTemplateDecl *Template;
1747
1748 DeclContext *DC = Template->getDeclContext();
1749 CXXRecordDecl *Primary = Template->getTemplatedDecl();
1750 DeclarationName DeductionGuideName =
1751 SemaRef.Context.DeclarationNames.getCXXDeductionGuideName(Template);
1752
1753 QualType DeducedType = SemaRef.Context.getTypeDeclType(Primary);
1754
1755 // Index adjustment to apply to convert depth-1 template parameters into
1756 // depth-0 template parameters.
1757 unsigned Depth1IndexAdjustment = Template->getTemplateParameters()->size();
1758
1759 /// Transform a constructor declaration into a deduction guide.
1760 NamedDecl *transformConstructor(FunctionTemplateDecl *FTD,
1761 CXXConstructorDecl *CD) {
1762 SmallVector<TemplateArgument, 16> SubstArgs;
1763
1764 LocalInstantiationScope Scope(SemaRef);
1765
1766 // C++ [over.match.class.deduct]p1:
1767 // -- For each constructor of the class template designated by the
1768 // template-name, a function template with the following properties:
1769
1770 // -- The template parameters are the template parameters of the class
1771 // template followed by the template parameters (including default
1772 // template arguments) of the constructor, if any.
1773 TemplateParameterList *TemplateParams = Template->getTemplateParameters();
1774 if (FTD
16.1
'FTD' is non-null
) {
17
Taking true branch
1775 TemplateParameterList *InnerParams = FTD->getTemplateParameters();
1776 SmallVector<NamedDecl *, 16> AllParams;
1777 AllParams.reserve(TemplateParams->size() + InnerParams->size());
1778 AllParams.insert(AllParams.begin(),
1779 TemplateParams->begin(), TemplateParams->end());
1780 SubstArgs.reserve(InnerParams->size());
1781
1782 // Later template parameters could refer to earlier ones, so build up
1783 // a list of substituted template arguments as we go.
1784 for (NamedDecl *Param : *InnerParams) {
18
Assuming '__begin3' is not equal to '__end3'
1785 MultiLevelTemplateArgumentList Args;
1786 Args.addOuterTemplateArguments(SubstArgs);
1787 Args.addOuterRetainedLevel();
1788 NamedDecl *NewParam = transformTemplateParameter(Param, Args);
19
Calling 'ConvertConstructorToDeductionGuideTransform::transformTemplateParameter'
1789 if (!NewParam)
1790 return nullptr;
1791 AllParams.push_back(NewParam);
1792 SubstArgs.push_back(SemaRef.Context.getCanonicalTemplateArgument(
1793 SemaRef.Context.getInjectedTemplateArg(NewParam)));
1794 }
1795 TemplateParams = TemplateParameterList::Create(
1796 SemaRef.Context, InnerParams->getTemplateLoc(),
1797 InnerParams->getLAngleLoc(), AllParams, InnerParams->getRAngleLoc(),
1798 /*FIXME: RequiresClause*/ nullptr);
1799 }
1800
1801 // If we built a new template-parameter-list, track that we need to
1802 // substitute references to the old parameters into references to the
1803 // new ones.
1804 MultiLevelTemplateArgumentList Args;
1805 if (FTD) {
1806 Args.addOuterTemplateArguments(SubstArgs);
1807 Args.addOuterRetainedLevel();
1808 }
1809
1810 FunctionProtoTypeLoc FPTL = CD->getTypeSourceInfo()->getTypeLoc()
1811 .getAsAdjusted<FunctionProtoTypeLoc>();
1812 assert(FPTL && "no prototype for constructor declaration")((FPTL && "no prototype for constructor declaration")
? static_cast<void> (0) : __assert_fail ("FPTL && \"no prototype for constructor declaration\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1812, __PRETTY_FUNCTION__))
;
1813
1814 // Transform the type of the function, adjusting the return type and
1815 // replacing references to the old parameters with references to the
1816 // new ones.
1817 TypeLocBuilder TLB;
1818 SmallVector<ParmVarDecl*, 8> Params;
1819 QualType NewType = transformFunctionProtoType(TLB, FPTL, Params, Args);
1820 if (NewType.isNull())
1821 return nullptr;
1822 TypeSourceInfo *NewTInfo = TLB.getTypeSourceInfo(SemaRef.Context, NewType);
1823
1824 return buildDeductionGuide(TemplateParams, CD->getExplicitSpecifier(),
1825 NewTInfo, CD->getBeginLoc(), CD->getLocation(),
1826 CD->getEndLoc());
1827 }
1828
1829 /// Build a deduction guide with the specified parameter types.
1830 NamedDecl *buildSimpleDeductionGuide(MutableArrayRef<QualType> ParamTypes) {
1831 SourceLocation Loc = Template->getLocation();
1832
1833 // Build the requested type.
1834 FunctionProtoType::ExtProtoInfo EPI;
1835 EPI.HasTrailingReturn = true;
1836 QualType Result = SemaRef.BuildFunctionType(DeducedType, ParamTypes, Loc,
1837 DeductionGuideName, EPI);
1838 TypeSourceInfo *TSI = SemaRef.Context.getTrivialTypeSourceInfo(Result, Loc);
1839
1840 FunctionProtoTypeLoc FPTL =
1841 TSI->getTypeLoc().castAs<FunctionProtoTypeLoc>();
1842
1843 // Build the parameters, needed during deduction / substitution.
1844 SmallVector<ParmVarDecl*, 4> Params;
1845 for (auto T : ParamTypes) {
1846 ParmVarDecl *NewParam = ParmVarDecl::Create(
1847 SemaRef.Context, DC, Loc, Loc, nullptr, T,
1848 SemaRef.Context.getTrivialTypeSourceInfo(T, Loc), SC_None, nullptr);
1849 NewParam->setScopeInfo(0, Params.size());
1850 FPTL.setParam(Params.size(), NewParam);
1851 Params.push_back(NewParam);
1852 }
1853
1854 return buildDeductionGuide(Template->getTemplateParameters(),
1855 ExplicitSpecifier(), TSI, Loc, Loc, Loc);
1856 }
1857
1858private:
1859 /// Transform a constructor template parameter into a deduction guide template
1860 /// parameter, rebuilding any internal references to earlier parameters and
1861 /// renumbering as we go.
1862 NamedDecl *transformTemplateParameter(NamedDecl *TemplateParam,
1863 MultiLevelTemplateArgumentList &Args) {
1864 if (auto *TTP
20.1
'TTP' is null
= dyn_cast<TemplateTypeParmDecl>(TemplateParam)) {
20
Assuming 'TemplateParam' is not a 'TemplateTypeParmDecl'
21
Taking false branch
1865 // TemplateTypeParmDecl's index cannot be changed after creation, so
1866 // substitute it directly.
1867 auto *NewTTP = TemplateTypeParmDecl::Create(
1868 SemaRef.Context, DC, TTP->getBeginLoc(), TTP->getLocation(),
1869 /*Depth*/ 0, Depth1IndexAdjustment + TTP->getIndex(),
1870 TTP->getIdentifier(), TTP->wasDeclaredWithTypename(),
1871 TTP->isParameterPack());
1872 if (TTP->hasDefaultArgument()) {
1873 TypeSourceInfo *InstantiatedDefaultArg =
1874 SemaRef.SubstType(TTP->getDefaultArgumentInfo(), Args,
1875 TTP->getDefaultArgumentLoc(), TTP->getDeclName());
1876 if (InstantiatedDefaultArg)
1877 NewTTP->setDefaultArgument(InstantiatedDefaultArg);
1878 }
1879 SemaRef.CurrentInstantiationScope->InstantiatedLocal(TemplateParam,
1880 NewTTP);
1881 return NewTTP;
1882 }
1883
1884 if (auto *TTP
22.1
'TTP' is non-null
= dyn_cast<TemplateTemplateParmDecl>(TemplateParam))
22
Assuming 'TemplateParam' is a 'TemplateTemplateParmDecl'
23
Taking true branch
1885 return transformTemplateParameterImpl(TTP, Args);
24
Calling 'ConvertConstructorToDeductionGuideTransform::transformTemplateParameterImpl'
1886
1887 return transformTemplateParameterImpl(
1888 cast<NonTypeTemplateParmDecl>(TemplateParam), Args);
1889 }
1890 template<typename TemplateParmDecl>
1891 TemplateParmDecl *
1892 transformTemplateParameterImpl(TemplateParmDecl *OldParam,
1893 MultiLevelTemplateArgumentList &Args) {
1894 // Ask the template instantiator to do the heavy lifting for us, then adjust
1895 // the index of the parameter once it's done.
1896 auto *NewParam =
26
'NewParam' initialized to a null pointer value
1897 cast_or_null<TemplateParmDecl>(SemaRef.SubstDecl(OldParam, DC, Args));
25
Assuming null pointer is passed into cast
1898 assert(NewParam->getDepth() == 0 && "unexpected template param depth")((NewParam->getDepth() == 0 && "unexpected template param depth"
) ? static_cast<void> (0) : __assert_fail ("NewParam->getDepth() == 0 && \"unexpected template param depth\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 1898, __PRETTY_FUNCTION__))
;
27
Called C++ object pointer is null
1899 NewParam->setPosition(NewParam->getPosition() + Depth1IndexAdjustment);
1900 return NewParam;
1901 }
1902
1903 QualType transformFunctionProtoType(TypeLocBuilder &TLB,
1904 FunctionProtoTypeLoc TL,
1905 SmallVectorImpl<ParmVarDecl*> &Params,
1906 MultiLevelTemplateArgumentList &Args) {
1907 SmallVector<QualType, 4> ParamTypes;
1908 const FunctionProtoType *T = TL.getTypePtr();
1909
1910 // -- The types of the function parameters are those of the constructor.
1911 for (auto *OldParam : TL.getParams()) {
1912 ParmVarDecl *NewParam = transformFunctionTypeParam(OldParam, Args);
1913 if (!NewParam)
1914 return QualType();
1915 ParamTypes.push_back(NewParam->getType());
1916 Params.push_back(NewParam);
1917 }
1918
1919 // -- The return type is the class template specialization designated by
1920 // the template-name and template arguments corresponding to the
1921 // template parameters obtained from the class template.
1922 //
1923 // We use the injected-class-name type of the primary template instead.
1924 // This has the convenient property that it is different from any type that
1925 // the user can write in a deduction-guide (because they cannot enter the
1926 // context of the template), so implicit deduction guides can never collide
1927 // with explicit ones.
1928 QualType ReturnType = DeducedType;
1929 TLB.pushTypeSpec(ReturnType).setNameLoc(Primary->getLocation());
1930
1931 // Resolving a wording defect, we also inherit the variadicness of the
1932 // constructor.
1933 FunctionProtoType::ExtProtoInfo EPI;
1934 EPI.Variadic = T->isVariadic();
1935 EPI.HasTrailingReturn = true;
1936
1937 QualType Result = SemaRef.BuildFunctionType(
1938 ReturnType, ParamTypes, TL.getBeginLoc(), DeductionGuideName, EPI);
1939 if (Result.isNull())
1940 return QualType();
1941
1942 FunctionProtoTypeLoc NewTL = TLB.push<FunctionProtoTypeLoc>(Result);
1943 NewTL.setLocalRangeBegin(TL.getLocalRangeBegin());
1944 NewTL.setLParenLoc(TL.getLParenLoc());
1945 NewTL.setRParenLoc(TL.getRParenLoc());
1946 NewTL.setExceptionSpecRange(SourceRange());
1947 NewTL.setLocalRangeEnd(TL.getLocalRangeEnd());
1948 for (unsigned I = 0, E = NewTL.getNumParams(); I != E; ++I)
1949 NewTL.setParam(I, Params[I]);
1950
1951 return Result;
1952 }
1953
1954 ParmVarDecl *
1955 transformFunctionTypeParam(ParmVarDecl *OldParam,
1956 MultiLevelTemplateArgumentList &Args) {
1957 TypeSourceInfo *OldDI = OldParam->getTypeSourceInfo();
1958 TypeSourceInfo *NewDI;
1959 if (auto PackTL = OldDI->getTypeLoc().getAs<PackExpansionTypeLoc>()) {
1960 // Expand out the one and only element in each inner pack.
1961 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, 0);
1962 NewDI =
1963 SemaRef.SubstType(PackTL.getPatternLoc(), Args,
1964 OldParam->getLocation(), OldParam->getDeclName());
1965 if (!NewDI) return nullptr;
1966 NewDI =
1967 SemaRef.CheckPackExpansion(NewDI, PackTL.getEllipsisLoc(),
1968 PackTL.getTypePtr()->getNumExpansions());
1969 } else
1970 NewDI = SemaRef.SubstType(OldDI, Args, OldParam->getLocation(),
1971 OldParam->getDeclName());
1972 if (!NewDI)
1973 return nullptr;
1974
1975 // Extract the type. This (for instance) replaces references to typedef
1976 // members of the current instantiations with the definitions of those
1977 // typedefs, avoiding triggering instantiation of the deduced type during
1978 // deduction.
1979 NewDI = ExtractTypeForDeductionGuide(SemaRef).transform(NewDI);
1980
1981 // Resolving a wording defect, we also inherit default arguments from the
1982 // constructor.
1983 ExprResult NewDefArg;
1984 if (OldParam->hasDefaultArg()) {
1985 NewDefArg = SemaRef.SubstExpr(OldParam->getDefaultArg(), Args);
1986 if (NewDefArg.isInvalid())
1987 return nullptr;
1988 }
1989
1990 ParmVarDecl *NewParam = ParmVarDecl::Create(SemaRef.Context, DC,
1991 OldParam->getInnerLocStart(),
1992 OldParam->getLocation(),
1993 OldParam->getIdentifier(),
1994 NewDI->getType(),
1995 NewDI,
1996 OldParam->getStorageClass(),
1997 NewDefArg.get());
1998 NewParam->setScopeInfo(OldParam->getFunctionScopeDepth(),
1999 OldParam->getFunctionScopeIndex());
2000 SemaRef.CurrentInstantiationScope->InstantiatedLocal(OldParam, NewParam);
2001 return NewParam;
2002 }
2003
2004 NamedDecl *buildDeductionGuide(TemplateParameterList *TemplateParams,
2005 ExplicitSpecifier ES, TypeSourceInfo *TInfo,
2006 SourceLocation LocStart, SourceLocation Loc,
2007 SourceLocation LocEnd) {
2008 DeclarationNameInfo Name(DeductionGuideName, Loc);
2009 ArrayRef<ParmVarDecl *> Params =
2010 TInfo->getTypeLoc().castAs<FunctionProtoTypeLoc>().getParams();
2011
2012 // Build the implicit deduction guide template.
2013 auto *Guide =
2014 CXXDeductionGuideDecl::Create(SemaRef.Context, DC, LocStart, ES, Name,
2015 TInfo->getType(), TInfo, LocEnd);
2016 Guide->setImplicit();
2017 Guide->setParams(Params);
2018
2019 for (auto *Param : Params)
2020 Param->setDeclContext(Guide);
2021
2022 auto *GuideTemplate = FunctionTemplateDecl::Create(
2023 SemaRef.Context, DC, Loc, DeductionGuideName, TemplateParams, Guide);
2024 GuideTemplate->setImplicit();
2025 Guide->setDescribedFunctionTemplate(GuideTemplate);
2026
2027 if (isa<CXXRecordDecl>(DC)) {
2028 Guide->setAccess(AS_public);
2029 GuideTemplate->setAccess(AS_public);
2030 }
2031
2032 DC->addDecl(GuideTemplate);
2033 return GuideTemplate;
2034 }
2035};
2036}
2037
2038void Sema::DeclareImplicitDeductionGuides(TemplateDecl *Template,
2039 SourceLocation Loc) {
2040 if (CXXRecordDecl *DefRecord
1.1
'DefRecord' is null
=
2
Taking false branch
2041 cast<CXXRecordDecl>(Template->getTemplatedDecl())->getDefinition()) {
1
The object is a 'CXXRecordDecl'
2042 TemplateDecl *DescribedTemplate = DefRecord->getDescribedClassTemplate();
2043 Template = DescribedTemplate ? DescribedTemplate : Template;
2044 }
2045
2046 DeclContext *DC = Template->getDeclContext();
2047 if (DC->isDependentContext())
3
Assuming the condition is false
4
Taking false branch
2048 return;
2049
2050 ConvertConstructorToDeductionGuideTransform Transform(
2051 *this, cast<ClassTemplateDecl>(Template));
5
'Template' is a 'ClassTemplateDecl'
2052 if (!isCompleteType(Loc, Transform.DeducedType))
6
Taking false branch
2053 return;
2054
2055 // Check whether we've already declared deduction guides for this template.
2056 // FIXME: Consider storing a flag on the template to indicate this.
2057 auto Existing = DC->lookup(Transform.DeductionGuideName);
2058 for (auto *D : Existing)
2059 if (D->isImplicit())
2060 return;
2061
2062 // In case we were expanding a pack when we attempted to declare deduction
2063 // guides, turn off pack expansion for everything we're about to do.
2064 ArgumentPackSubstitutionIndexRAII SubstIndex(*this, -1);
2065 // Create a template instantiation record to track the "instantiation" of
2066 // constructors into deduction guides.
2067 // FIXME: Add a kind for this to give more meaningful diagnostics. But can
2068 // this substitution process actually fail?
2069 InstantiatingTemplate BuildingDeductionGuides(*this, Loc, Template);
2070 if (BuildingDeductionGuides.isInvalid())
7
Assuming the condition is false
8
Taking false branch
2071 return;
2072
2073 // Convert declared constructors into deduction guide templates.
2074 // FIXME: Skip constructors for which deduction must necessarily fail (those
2075 // for which some class template parameter without a default argument never
2076 // appears in a deduced context).
2077 bool AddedAny = false;
2078 for (NamedDecl *D : LookupConstructors(Transform.Primary)) {
2079 D = D->getUnderlyingDecl();
2080 if (D->isInvalidDecl() || D->isImplicit())
9
Assuming the condition is false
10
Assuming the condition is false
11
Taking false branch
2081 continue;
2082 D = cast<NamedDecl>(D->getCanonicalDecl());
12
The object is a 'NamedDecl'
2083
2084 auto *FTD = dyn_cast<FunctionTemplateDecl>(D);
13
Assuming 'D' is a 'FunctionTemplateDecl'
2085 auto *CD =
2086 dyn_cast_or_null<CXXConstructorDecl>(FTD
13.1
'FTD' is non-null
? FTD->getTemplatedDecl() : D)
;
14
'?' condition is true
15
Assuming the object is a 'CXXConstructorDecl'
2087 // Class-scope explicit specializations (MS extension) do not result in
2088 // deduction guides.
2089 if (!CD
15.1
'CD' is non-null
|| (!FTD
15.2
'FTD' is non-null
&& CD->isFunctionTemplateSpecialization()))
2090 continue;
2091
2092 Transform.transformConstructor(FTD, CD);
16
Calling 'ConvertConstructorToDeductionGuideTransform::transformConstructor'
2093 AddedAny = true;
2094 }
2095
2096 // C++17 [over.match.class.deduct]
2097 // -- If C is not defined or does not declare any constructors, an
2098 // additional function template derived as above from a hypothetical
2099 // constructor C().
2100 if (!AddedAny)
2101 Transform.buildSimpleDeductionGuide(None);
2102
2103 // -- An additional function template derived as above from a hypothetical
2104 // constructor C(C), called the copy deduction candidate.
2105 cast<CXXDeductionGuideDecl>(
2106 cast<FunctionTemplateDecl>(
2107 Transform.buildSimpleDeductionGuide(Transform.DeducedType))
2108 ->getTemplatedDecl())
2109 ->setIsCopyDeductionCandidate();
2110}
2111
2112/// Diagnose the presence of a default template argument on a
2113/// template parameter, which is ill-formed in certain contexts.
2114///
2115/// \returns true if the default template argument should be dropped.
2116static bool DiagnoseDefaultTemplateArgument(Sema &S,
2117 Sema::TemplateParamListContext TPC,
2118 SourceLocation ParamLoc,
2119 SourceRange DefArgRange) {
2120 switch (TPC) {
2121 case Sema::TPC_ClassTemplate:
2122 case Sema::TPC_VarTemplate:
2123 case Sema::TPC_TypeAliasTemplate:
2124 return false;
2125
2126 case Sema::TPC_FunctionTemplate:
2127 case Sema::TPC_FriendFunctionTemplateDefinition:
2128 // C++ [temp.param]p9:
2129 // A default template-argument shall not be specified in a
2130 // function template declaration or a function template
2131 // definition [...]
2132 // If a friend function template declaration specifies a default
2133 // template-argument, that declaration shall be a definition and shall be
2134 // the only declaration of the function template in the translation unit.
2135 // (C++98/03 doesn't have this wording; see DR226).
2136 S.Diag(ParamLoc, S.getLangOpts().CPlusPlus11 ?
2137 diag::warn_cxx98_compat_template_parameter_default_in_function_template
2138 : diag::ext_template_parameter_default_in_function_template)
2139 << DefArgRange;
2140 return false;
2141
2142 case Sema::TPC_ClassTemplateMember:
2143 // C++0x [temp.param]p9:
2144 // A default template-argument shall not be specified in the
2145 // template-parameter-lists of the definition of a member of a
2146 // class template that appears outside of the member's class.
2147 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
2148 << DefArgRange;
2149 return true;
2150
2151 case Sema::TPC_FriendClassTemplate:
2152 case Sema::TPC_FriendFunctionTemplate:
2153 // C++ [temp.param]p9:
2154 // A default template-argument shall not be specified in a
2155 // friend template declaration.
2156 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
2157 << DefArgRange;
2158 return true;
2159
2160 // FIXME: C++0x [temp.param]p9 allows default template-arguments
2161 // for friend function templates if there is only a single
2162 // declaration (and it is a definition). Strange!
2163 }
2164
2165 llvm_unreachable("Invalid TemplateParamListContext!")::llvm::llvm_unreachable_internal("Invalid TemplateParamListContext!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2165)
;
2166}
2167
2168/// Check for unexpanded parameter packs within the template parameters
2169/// of a template template parameter, recursively.
2170static bool DiagnoseUnexpandedParameterPacks(Sema &S,
2171 TemplateTemplateParmDecl *TTP) {
2172 // A template template parameter which is a parameter pack is also a pack
2173 // expansion.
2174 if (TTP->isParameterPack())
2175 return false;
2176
2177 TemplateParameterList *Params = TTP->getTemplateParameters();
2178 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
2179 NamedDecl *P = Params->getParam(I);
2180 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) {
2181 if (!NTTP->isParameterPack() &&
2182 S.DiagnoseUnexpandedParameterPack(NTTP->getLocation(),
2183 NTTP->getTypeSourceInfo(),
2184 Sema::UPPC_NonTypeTemplateParameterType))
2185 return true;
2186
2187 continue;
2188 }
2189
2190 if (TemplateTemplateParmDecl *InnerTTP
2191 = dyn_cast<TemplateTemplateParmDecl>(P))
2192 if (DiagnoseUnexpandedParameterPacks(S, InnerTTP))
2193 return true;
2194 }
2195
2196 return false;
2197}
2198
2199/// Checks the validity of a template parameter list, possibly
2200/// considering the template parameter list from a previous
2201/// declaration.
2202///
2203/// If an "old" template parameter list is provided, it must be
2204/// equivalent (per TemplateParameterListsAreEqual) to the "new"
2205/// template parameter list.
2206///
2207/// \param NewParams Template parameter list for a new template
2208/// declaration. This template parameter list will be updated with any
2209/// default arguments that are carried through from the previous
2210/// template parameter list.
2211///
2212/// \param OldParams If provided, template parameter list from a
2213/// previous declaration of the same template. Default template
2214/// arguments will be merged from the old template parameter list to
2215/// the new template parameter list.
2216///
2217/// \param TPC Describes the context in which we are checking the given
2218/// template parameter list.
2219///
2220/// \param SkipBody If we might have already made a prior merged definition
2221/// of this template visible, the corresponding body-skipping information.
2222/// Default argument redefinition is not an error when skipping such a body,
2223/// because (under the ODR) we can assume the default arguments are the same
2224/// as the prior merged definition.
2225///
2226/// \returns true if an error occurred, false otherwise.
2227bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
2228 TemplateParameterList *OldParams,
2229 TemplateParamListContext TPC,
2230 SkipBodyInfo *SkipBody) {
2231 bool Invalid = false;
2232
2233 // C++ [temp.param]p10:
2234 // The set of default template-arguments available for use with a
2235 // template declaration or definition is obtained by merging the
2236 // default arguments from the definition (if in scope) and all
2237 // declarations in scope in the same way default function
2238 // arguments are (8.3.6).
2239 bool SawDefaultArgument = false;
2240 SourceLocation PreviousDefaultArgLoc;
2241
2242 // Dummy initialization to avoid warnings.
2243 TemplateParameterList::iterator OldParam = NewParams->end();
2244 if (OldParams)
2245 OldParam = OldParams->begin();
2246
2247 bool RemoveDefaultArguments = false;
2248 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
2249 NewParamEnd = NewParams->end();
2250 NewParam != NewParamEnd; ++NewParam) {
2251 // Variables used to diagnose redundant default arguments
2252 bool RedundantDefaultArg = false;
2253 SourceLocation OldDefaultLoc;
2254 SourceLocation NewDefaultLoc;
2255
2256 // Variable used to diagnose missing default arguments
2257 bool MissingDefaultArg = false;
2258
2259 // Variable used to diagnose non-final parameter packs
2260 bool SawParameterPack = false;
2261
2262 if (TemplateTypeParmDecl *NewTypeParm
2263 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
2264 // Check the presence of a default argument here.
2265 if (NewTypeParm->hasDefaultArgument() &&
2266 DiagnoseDefaultTemplateArgument(*this, TPC,
2267 NewTypeParm->getLocation(),
2268 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
2269 .getSourceRange()))
2270 NewTypeParm->removeDefaultArgument();
2271
2272 // Merge default arguments for template type parameters.
2273 TemplateTypeParmDecl *OldTypeParm
2274 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : nullptr;
2275 if (NewTypeParm->isParameterPack()) {
2276 assert(!NewTypeParm->hasDefaultArgument() &&((!NewTypeParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewTypeParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2277, __PRETTY_FUNCTION__))
2277 "Parameter packs can't have a default argument!")((!NewTypeParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewTypeParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2277, __PRETTY_FUNCTION__))
;
2278 SawParameterPack = true;
2279 } else if (OldTypeParm && hasVisibleDefaultArgument(OldTypeParm) &&
2280 NewTypeParm->hasDefaultArgument() &&
2281 (!SkipBody || !SkipBody->ShouldSkip)) {
2282 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
2283 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
2284 SawDefaultArgument = true;
2285 RedundantDefaultArg = true;
2286 PreviousDefaultArgLoc = NewDefaultLoc;
2287 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
2288 // Merge the default argument from the old declaration to the
2289 // new declaration.
2290 NewTypeParm->setInheritedDefaultArgument(Context, OldTypeParm);
2291 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
2292 } else if (NewTypeParm->hasDefaultArgument()) {
2293 SawDefaultArgument = true;
2294 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
2295 } else if (SawDefaultArgument)
2296 MissingDefaultArg = true;
2297 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
2298 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
2299 // Check for unexpanded parameter packs.
2300 if (!NewNonTypeParm->isParameterPack() &&
2301 DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(),
2302 NewNonTypeParm->getTypeSourceInfo(),
2303 UPPC_NonTypeTemplateParameterType)) {
2304 Invalid = true;
2305 continue;
2306 }
2307
2308 // Check the presence of a default argument here.
2309 if (NewNonTypeParm->hasDefaultArgument() &&
2310 DiagnoseDefaultTemplateArgument(*this, TPC,
2311 NewNonTypeParm->getLocation(),
2312 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
2313 NewNonTypeParm->removeDefaultArgument();
2314 }
2315
2316 // Merge default arguments for non-type template parameters
2317 NonTypeTemplateParmDecl *OldNonTypeParm
2318 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : nullptr;
2319 if (NewNonTypeParm->isParameterPack()) {
2320 assert(!NewNonTypeParm->hasDefaultArgument() &&((!NewNonTypeParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewNonTypeParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2321, __PRETTY_FUNCTION__))
2321 "Parameter packs can't have a default argument!")((!NewNonTypeParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewNonTypeParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2321, __PRETTY_FUNCTION__))
;
2322 if (!NewNonTypeParm->isPackExpansion())
2323 SawParameterPack = true;
2324 } else if (OldNonTypeParm && hasVisibleDefaultArgument(OldNonTypeParm) &&
2325 NewNonTypeParm->hasDefaultArgument() &&
2326 (!SkipBody || !SkipBody->ShouldSkip)) {
2327 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
2328 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
2329 SawDefaultArgument = true;
2330 RedundantDefaultArg = true;
2331 PreviousDefaultArgLoc = NewDefaultLoc;
2332 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
2333 // Merge the default argument from the old declaration to the
2334 // new declaration.
2335 NewNonTypeParm->setInheritedDefaultArgument(Context, OldNonTypeParm);
2336 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
2337 } else if (NewNonTypeParm->hasDefaultArgument()) {
2338 SawDefaultArgument = true;
2339 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
2340 } else if (SawDefaultArgument)
2341 MissingDefaultArg = true;
2342 } else {
2343 TemplateTemplateParmDecl *NewTemplateParm
2344 = cast<TemplateTemplateParmDecl>(*NewParam);
2345
2346 // Check for unexpanded parameter packs, recursively.
2347 if (::DiagnoseUnexpandedParameterPacks(*this, NewTemplateParm)) {
2348 Invalid = true;
2349 continue;
2350 }
2351
2352 // Check the presence of a default argument here.
2353 if (NewTemplateParm->hasDefaultArgument() &&
2354 DiagnoseDefaultTemplateArgument(*this, TPC,
2355 NewTemplateParm->getLocation(),
2356 NewTemplateParm->getDefaultArgument().getSourceRange()))
2357 NewTemplateParm->removeDefaultArgument();
2358
2359 // Merge default arguments for template template parameters
2360 TemplateTemplateParmDecl *OldTemplateParm
2361 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : nullptr;
2362 if (NewTemplateParm->isParameterPack()) {
2363 assert(!NewTemplateParm->hasDefaultArgument() &&((!NewTemplateParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewTemplateParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2364, __PRETTY_FUNCTION__))
2364 "Parameter packs can't have a default argument!")((!NewTemplateParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"
) ? static_cast<void> (0) : __assert_fail ("!NewTemplateParm->hasDefaultArgument() && \"Parameter packs can't have a default argument!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 2364, __PRETTY_FUNCTION__))
;
2365 if (!NewTemplateParm->isPackExpansion())
2366 SawParameterPack = true;
2367 } else if (OldTemplateParm &&
2368 hasVisibleDefaultArgument(OldTemplateParm) &&
2369 NewTemplateParm->hasDefaultArgument() &&
2370 (!SkipBody || !SkipBody->ShouldSkip)) {
2371 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
2372 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
2373 SawDefaultArgument = true;
2374 RedundantDefaultArg = true;
2375 PreviousDefaultArgLoc = NewDefaultLoc;
2376 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
2377 // Merge the default argument from the old declaration to the
2378 // new declaration.
2379 NewTemplateParm->setInheritedDefaultArgument(Context, OldTemplateParm);
2380 PreviousDefaultArgLoc
2381 = OldTemplateParm->getDefaultArgument().getLocation();
2382 } else if (NewTemplateParm->hasDefaultArgument()) {
2383 SawDefaultArgument = true;
2384 PreviousDefaultArgLoc
2385 = NewTemplateParm->getDefaultArgument().getLocation();
2386 } else if (SawDefaultArgument)
2387 MissingDefaultArg = true;
2388 }
2389
2390 // C++11 [temp.param]p11:
2391 // If a template parameter of a primary class template or alias template
2392 // is a template parameter pack, it shall be the last template parameter.
2393 if (SawParameterPack && (NewParam + 1) != NewParamEnd &&
2394 (TPC == TPC_ClassTemplate || TPC == TPC_VarTemplate ||
2395 TPC == TPC_TypeAliasTemplate)) {
2396 Diag((*NewParam)->getLocation(),
2397 diag::err_template_param_pack_must_be_last_template_parameter);
2398 Invalid = true;
2399 }
2400
2401 if (RedundantDefaultArg) {
2402 // C++ [temp.param]p12:
2403 // A template-parameter shall not be given default arguments
2404 // by two different declarations in the same scope.
2405 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
2406 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
2407 Invalid = true;
2408 } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
2409 // C++ [temp.param]p11:
2410 // If a template-parameter of a class template has a default
2411 // template-argument, each subsequent template-parameter shall either
2412 // have a default template-argument supplied or be a template parameter
2413 // pack.
2414 Diag((*NewParam)->getLocation(),
2415 diag::err_template_param_default_arg_missing);
2416 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
2417 Invalid = true;
2418 RemoveDefaultArguments = true;
2419 }
2420
2421 // If we have an old template parameter list that we're merging
2422 // in, move on to the next parameter.
2423 if (OldParams)
2424 ++OldParam;
2425 }
2426
2427 // We were missing some default arguments at the end of the list, so remove
2428 // all of the default arguments.
2429 if (RemoveDefaultArguments) {
2430 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
2431 NewParamEnd = NewParams->end();
2432 NewParam != NewParamEnd; ++NewParam) {
2433 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*NewParam))
2434 TTP->removeDefaultArgument();
2435 else if (NonTypeTemplateParmDecl *NTTP
2436 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam))
2437 NTTP->removeDefaultArgument();
2438 else
2439 cast<TemplateTemplateParmDecl>(*NewParam)->removeDefaultArgument();
2440 }
2441 }
2442
2443 return Invalid;
2444}
2445
2446namespace {
2447
2448/// A class which looks for a use of a certain level of template
2449/// parameter.
2450struct DependencyChecker : RecursiveASTVisitor<DependencyChecker> {
2451 typedef RecursiveASTVisitor<DependencyChecker> super;
2452
2453 unsigned Depth;
2454
2455 // Whether we're looking for a use of a template parameter that makes the
2456 // overall construct type-dependent / a dependent type. This is strictly
2457 // best-effort for now; we may fail to match at all for a dependent type
2458 // in some cases if this is set.
2459 bool IgnoreNonTypeDependent;
2460
2461 bool Match;
2462 SourceLocation MatchLoc;
2463
2464 DependencyChecker(unsigned Depth, bool IgnoreNonTypeDependent)
2465 : Depth(Depth), IgnoreNonTypeDependent(IgnoreNonTypeDependent),
2466 Match(false) {}
2467
2468 DependencyChecker(TemplateParameterList *Params, bool IgnoreNonTypeDependent)
2469 : IgnoreNonTypeDependent(IgnoreNonTypeDependent), Match(false) {
2470 NamedDecl *ND = Params->getParam(0);
2471 if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
2472 Depth = PD->getDepth();
2473 } else if (NonTypeTemplateParmDecl *PD =
2474 dyn_cast<NonTypeTemplateParmDecl>(ND)) {
2475 Depth = PD->getDepth();
2476 } else {
2477 Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
2478 }
2479 }
2480
2481 bool Matches(unsigned ParmDepth, SourceLocation Loc = SourceLocation()) {
2482 if (ParmDepth >= Depth) {
2483 Match = true;
2484 MatchLoc = Loc;
2485 return true;
2486 }
2487 return false;
2488 }
2489
2490 bool TraverseStmt(Stmt *S, DataRecursionQueue *Q = nullptr) {
2491 // Prune out non-type-dependent expressions if requested. This can
2492 // sometimes result in us failing to find a template parameter reference
2493 // (if a value-dependent expression creates a dependent type), but this
2494 // mode is best-effort only.
2495 if (auto *E = dyn_cast_or_null<Expr>(S))
2496 if (IgnoreNonTypeDependent && !E->isTypeDependent())
2497 return true;
2498 return super::TraverseStmt(S, Q);
2499 }
2500
2501 bool TraverseTypeLoc(TypeLoc TL) {
2502 if (IgnoreNonTypeDependent && !TL.isNull() &&
2503 !TL.getType()->isDependentType())
2504 return true;
2505 return super::TraverseTypeLoc(TL);
2506 }
2507
2508 bool VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
2509 return !Matches(TL.getTypePtr()->getDepth(), TL.getNameLoc());
2510 }
2511
2512 bool VisitTemplateTypeParmType(const TemplateTypeParmType *T) {
2513 // For a best-effort search, keep looking until we find a location.
2514 return IgnoreNonTypeDependent || !Matches(T->getDepth());
2515 }
2516
2517 bool TraverseTemplateName(TemplateName N) {
2518 if (TemplateTemplateParmDecl *PD =
2519 dyn_cast_or_null<TemplateTemplateParmDecl>(N.getAsTemplateDecl()))
2520 if (Matches(PD->getDepth()))
2521 return false;
2522 return super::TraverseTemplateName(N);
2523 }
2524
2525 bool VisitDeclRefExpr(DeclRefExpr *E) {
2526 if (NonTypeTemplateParmDecl *PD =
2527 dyn_cast<NonTypeTemplateParmDecl>(E->getDecl()))
2528 if (Matches(PD->getDepth(), E->getExprLoc()))
2529 return false;
2530 return super::VisitDeclRefExpr(E);
2531 }
2532
2533 bool VisitSubstTemplateTypeParmType(const SubstTemplateTypeParmType *T) {
2534 return TraverseType(T->getReplacementType());
2535 }
2536
2537 bool
2538 VisitSubstTemplateTypeParmPackType(const SubstTemplateTypeParmPackType *T) {
2539 return TraverseTemplateArgument(T->getArgumentPack());
2540 }
2541
2542 bool TraverseInjectedClassNameType(const InjectedClassNameType *T) {
2543 return TraverseType(T->getInjectedSpecializationType());
2544 }
2545};
2546} // end anonymous namespace
2547
2548/// Determines whether a given type depends on the given parameter
2549/// list.
2550static bool
2551DependsOnTemplateParameters(QualType T, TemplateParameterList *Params) {
2552 if (!Params->size())
2553 return false;
2554
2555 DependencyChecker Checker(Params, /*IgnoreNonTypeDependent*/false);
2556 Checker.TraverseType(T);
2557 return Checker.Match;
2558}
2559
2560// Find the source range corresponding to the named type in the given
2561// nested-name-specifier, if any.
2562static SourceRange getRangeOfTypeInNestedNameSpecifier(ASTContext &Context,
2563 QualType T,
2564 const CXXScopeSpec &SS) {
2565 NestedNameSpecifierLoc NNSLoc(SS.getScopeRep(), SS.location_data());
2566 while (NestedNameSpecifier *NNS = NNSLoc.getNestedNameSpecifier()) {
2567 if (const Type *CurType = NNS->getAsType()) {
2568 if (Context.hasSameUnqualifiedType(T, QualType(CurType, 0)))
2569 return NNSLoc.getTypeLoc().getSourceRange();
2570 } else
2571 break;
2572
2573 NNSLoc = NNSLoc.getPrefix();
2574 }
2575
2576 return SourceRange();
2577}
2578
2579/// Match the given template parameter lists to the given scope
2580/// specifier, returning the template parameter list that applies to the
2581/// name.
2582///
2583/// \param DeclStartLoc the start of the declaration that has a scope
2584/// specifier or a template parameter list.
2585///
2586/// \param DeclLoc The location of the declaration itself.
2587///
2588/// \param SS the scope specifier that will be matched to the given template
2589/// parameter lists. This scope specifier precedes a qualified name that is
2590/// being declared.
2591///
2592/// \param TemplateId The template-id following the scope specifier, if there
2593/// is one. Used to check for a missing 'template<>'.
2594///
2595/// \param ParamLists the template parameter lists, from the outermost to the
2596/// innermost template parameter lists.
2597///
2598/// \param IsFriend Whether to apply the slightly different rules for
2599/// matching template parameters to scope specifiers in friend
2600/// declarations.
2601///
2602/// \param IsMemberSpecialization will be set true if the scope specifier
2603/// denotes a fully-specialized type, and therefore this is a declaration of
2604/// a member specialization.
2605///
2606/// \returns the template parameter list, if any, that corresponds to the
2607/// name that is preceded by the scope specifier @p SS. This template
2608/// parameter list may have template parameters (if we're declaring a
2609/// template) or may have no template parameters (if we're declaring a
2610/// template specialization), or may be NULL (if what we're declaring isn't
2611/// itself a template).
2612TemplateParameterList *Sema::MatchTemplateParametersToScopeSpecifier(
2613 SourceLocation DeclStartLoc, SourceLocation DeclLoc, const CXXScopeSpec &SS,
2614 TemplateIdAnnotation *TemplateId,
2615 ArrayRef<TemplateParameterList *> ParamLists, bool IsFriend,
2616 bool &IsMemberSpecialization, bool &Invalid) {
2617 IsMemberSpecialization = false;
2618 Invalid = false;
2619
2620 // The sequence of nested types to which we will match up the template
2621 // parameter lists. We first build this list by starting with the type named
2622 // by the nested-name-specifier and walking out until we run out of types.
2623 SmallVector<QualType, 4> NestedTypes;
2624 QualType T;
2625 if (SS.getScopeRep()) {
2626 if (CXXRecordDecl *Record
2627 = dyn_cast_or_null<CXXRecordDecl>(computeDeclContext(SS, true)))
2628 T = Context.getTypeDeclType(Record);
2629 else
2630 T = QualType(SS.getScopeRep()->getAsType(), 0);
2631 }
2632
2633 // If we found an explicit specialization that prevents us from needing
2634 // 'template<>' headers, this will be set to the location of that
2635 // explicit specialization.
2636 SourceLocation ExplicitSpecLoc;
2637
2638 while (!T.isNull()) {
2639 NestedTypes.push_back(T);
2640
2641 // Retrieve the parent of a record type.
2642 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
2643 // If this type is an explicit specialization, we're done.
2644 if (ClassTemplateSpecializationDecl *Spec
2645 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
2646 if (!isa<ClassTemplatePartialSpecializationDecl>(Spec) &&
2647 Spec->getSpecializationKind() == TSK_ExplicitSpecialization) {
2648 ExplicitSpecLoc = Spec->getLocation();
2649 break;
2650 }
2651 } else if (Record->getTemplateSpecializationKind()
2652 == TSK_ExplicitSpecialization) {
2653 ExplicitSpecLoc = Record->getLocation();
2654 break;
2655 }
2656
2657 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Record->getParent()))
2658 T = Context.getTypeDeclType(Parent);
2659 else
2660 T = QualType();
2661 continue;
2662 }
2663
2664 if (const TemplateSpecializationType *TST
2665 = T->getAs<TemplateSpecializationType>()) {
2666 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
2667 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Template->getDeclContext()))
2668 T = Context.getTypeDeclType(Parent);
2669 else
2670 T = QualType();
2671 continue;
2672 }
2673 }
2674
2675 // Look one step prior in a dependent template specialization type.
2676 if (const DependentTemplateSpecializationType *DependentTST
2677 = T->getAs<DependentTemplateSpecializationType>()) {
2678 if (NestedNameSpecifier *NNS = DependentTST->getQualifier())
2679 T = QualType(NNS->getAsType(), 0);
2680 else
2681 T = QualType();
2682 continue;
2683 }
2684
2685 // Look one step prior in a dependent name type.
2686 if (const DependentNameType *DependentName = T->getAs<DependentNameType>()){
2687 if (NestedNameSpecifier *NNS = DependentName->getQualifier())
2688 T = QualType(NNS->getAsType(), 0);
2689 else
2690 T = QualType();
2691 continue;
2692 }
2693
2694 // Retrieve the parent of an enumeration type.
2695 if (const EnumType *EnumT = T->getAs<EnumType>()) {
2696 // FIXME: Forward-declared enums require a TSK_ExplicitSpecialization
2697 // check here.
2698 EnumDecl *Enum = EnumT->getDecl();
2699
2700 // Get to the parent type.
2701 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Enum->getParent()))
2702 T = Context.getTypeDeclType(Parent);
2703 else
2704 T = QualType();
2705 continue;
2706 }
2707
2708 T = QualType();
2709 }
2710 // Reverse the nested types list, since we want to traverse from the outermost
2711 // to the innermost while checking template-parameter-lists.
2712 std::reverse(NestedTypes.begin(), NestedTypes.end());
2713
2714 // C++0x [temp.expl.spec]p17:
2715 // A member or a member template may be nested within many
2716 // enclosing class templates. In an explicit specialization for
2717 // such a member, the member declaration shall be preceded by a
2718 // template<> for each enclosing class template that is
2719 // explicitly specialized.
2720 bool SawNonEmptyTemplateParameterList = false;
2721
2722 auto CheckExplicitSpecialization = [&](SourceRange Range, bool Recovery) {
2723 if (SawNonEmptyTemplateParameterList) {
2724 Diag(DeclLoc, diag::err_specialize_member_of_template)
2725 << !Recovery << Range;
2726 Invalid = true;
2727 IsMemberSpecialization = false;
2728 return true;
2729 }
2730
2731 return false;
2732 };
2733
2734 auto DiagnoseMissingExplicitSpecialization = [&] (SourceRange Range) {
2735 // Check that we can have an explicit specialization here.
2736 if (CheckExplicitSpecialization(Range, true))
2737 return true;
2738
2739 // We don't have a template header, but we should.
2740 SourceLocation ExpectedTemplateLoc;
2741 if (!ParamLists.empty())
2742 ExpectedTemplateLoc = ParamLists[0]->getTemplateLoc();
2743 else
2744 ExpectedTemplateLoc = DeclStartLoc;
2745
2746 Diag(DeclLoc, diag::err_template_spec_needs_header)
2747 << Range
2748 << FixItHint::CreateInsertion(ExpectedTemplateLoc, "template<> ");
2749 return false;
2750 };
2751
2752 unsigned ParamIdx = 0;
2753 for (unsigned TypeIdx = 0, NumTypes = NestedTypes.size(); TypeIdx != NumTypes;
2754 ++TypeIdx) {
2755 T = NestedTypes[TypeIdx];
2756
2757 // Whether we expect a 'template<>' header.
2758 bool NeedEmptyTemplateHeader = false;
2759
2760 // Whether we expect a template header with parameters.
2761 bool NeedNonemptyTemplateHeader = false;
2762
2763 // For a dependent type, the set of template parameters that we
2764 // expect to see.
2765 TemplateParameterList *ExpectedTemplateParams = nullptr;
2766
2767 // C++0x [temp.expl.spec]p15:
2768 // A member or a member template may be nested within many enclosing
2769 // class templates. In an explicit specialization for such a member, the
2770 // member declaration shall be preceded by a template<> for each
2771 // enclosing class template that is explicitly specialized.
2772 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
2773 if (ClassTemplatePartialSpecializationDecl *Partial
2774 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) {
2775 ExpectedTemplateParams = Partial->getTemplateParameters();
2776 NeedNonemptyTemplateHeader = true;
2777 } else if (Record->isDependentType()) {
2778 if (Record->getDescribedClassTemplate()) {
2779 ExpectedTemplateParams = Record->getDescribedClassTemplate()
2780 ->getTemplateParameters();
2781 NeedNonemptyTemplateHeader = true;
2782 }
2783 } else if (ClassTemplateSpecializationDecl *Spec
2784 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
2785 // C++0x [temp.expl.spec]p4:
2786 // Members of an explicitly specialized class template are defined
2787 // in the same manner as members of normal classes, and not using
2788 // the template<> syntax.
2789 if (Spec->getSpecializationKind() != TSK_ExplicitSpecialization)
2790 NeedEmptyTemplateHeader = true;
2791 else
2792 continue;
2793 } else if (Record->getTemplateSpecializationKind()) {
2794 if (Record->getTemplateSpecializationKind()
2795 != TSK_ExplicitSpecialization &&
2796 TypeIdx == NumTypes - 1)
2797 IsMemberSpecialization = true;
2798
2799 continue;
2800 }
2801 } else if (const TemplateSpecializationType *TST
2802 = T->getAs<TemplateSpecializationType>()) {
2803 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
2804 ExpectedTemplateParams = Template->getTemplateParameters();
2805 NeedNonemptyTemplateHeader = true;
2806 }
2807 } else if (T->getAs<DependentTemplateSpecializationType>()) {
2808 // FIXME: We actually could/should check the template arguments here
2809 // against the corresponding template parameter list.
2810 NeedNonemptyTemplateHeader = false;
2811 }
2812
2813 // C++ [temp.expl.spec]p16:
2814 // In an explicit specialization declaration for a member of a class
2815 // template or a member template that ap- pears in namespace scope, the
2816 // member template and some of its enclosing class templates may remain
2817 // unspecialized, except that the declaration shall not explicitly
2818 // specialize a class member template if its en- closing class templates
2819 // are not explicitly specialized as well.
2820 if (ParamIdx < ParamLists.size()) {
2821 if (ParamLists[ParamIdx]->size() == 0) {
2822 if (CheckExplicitSpecialization(ParamLists[ParamIdx]->getSourceRange(),
2823 false))
2824 return nullptr;
2825 } else
2826 SawNonEmptyTemplateParameterList = true;
2827 }
2828
2829 if (NeedEmptyTemplateHeader) {
2830 // If we're on the last of the types, and we need a 'template<>' header
2831 // here, then it's a member specialization.
2832 if (TypeIdx == NumTypes - 1)
2833 IsMemberSpecialization = true;
2834
2835 if (ParamIdx < ParamLists.size()) {
2836 if (ParamLists[ParamIdx]->size() > 0) {
2837 // The header has template parameters when it shouldn't. Complain.
2838 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
2839 diag::err_template_param_list_matches_nontemplate)
2840 << T
2841 << SourceRange(ParamLists[ParamIdx]->getLAngleLoc(),
2842 ParamLists[ParamIdx]->getRAngleLoc())
2843 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
2844 Invalid = true;
2845 return nullptr;
2846 }
2847
2848 // Consume this template header.
2849 ++ParamIdx;
2850 continue;
2851 }
2852
2853 if (!IsFriend)
2854 if (DiagnoseMissingExplicitSpecialization(
2855 getRangeOfTypeInNestedNameSpecifier(Context, T, SS)))
2856 return nullptr;
2857
2858 continue;
2859 }
2860
2861 if (NeedNonemptyTemplateHeader) {
2862 // In friend declarations we can have template-ids which don't
2863 // depend on the corresponding template parameter lists. But
2864 // assume that empty parameter lists are supposed to match this
2865 // template-id.
2866 if (IsFriend && T->isDependentType()) {
2867 if (ParamIdx < ParamLists.size() &&
2868 DependsOnTemplateParameters(T, ParamLists[ParamIdx]))
2869 ExpectedTemplateParams = nullptr;
2870 else
2871 continue;
2872 }
2873
2874 if (ParamIdx < ParamLists.size()) {
2875 // Check the template parameter list, if we can.
2876 if (ExpectedTemplateParams &&
2877 !TemplateParameterListsAreEqual(ParamLists[ParamIdx],
2878 ExpectedTemplateParams,
2879 true, TPL_TemplateMatch))
2880 Invalid = true;
2881
2882 if (!Invalid &&
2883 CheckTemplateParameterList(ParamLists[ParamIdx], nullptr,
2884 TPC_ClassTemplateMember))
2885 Invalid = true;
2886
2887 ++ParamIdx;
2888 continue;
2889 }
2890
2891 Diag(DeclLoc, diag::err_template_spec_needs_template_parameters)
2892 << T
2893 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
2894 Invalid = true;
2895 continue;
2896 }
2897 }
2898
2899 // If there were at least as many template-ids as there were template
2900 // parameter lists, then there are no template parameter lists remaining for
2901 // the declaration itself.
2902 if (ParamIdx >= ParamLists.size()) {
2903 if (TemplateId && !IsFriend) {
2904 // We don't have a template header for the declaration itself, but we
2905 // should.
2906 DiagnoseMissingExplicitSpecialization(SourceRange(TemplateId->LAngleLoc,
2907 TemplateId->RAngleLoc));
2908
2909 // Fabricate an empty template parameter list for the invented header.
2910 return TemplateParameterList::Create(Context, SourceLocation(),
2911 SourceLocation(), None,
2912 SourceLocation(), nullptr);
2913 }
2914
2915 return nullptr;
2916 }
2917
2918 // If there were too many template parameter lists, complain about that now.
2919 if (ParamIdx < ParamLists.size() - 1) {
2920 bool HasAnyExplicitSpecHeader = false;
2921 bool AllExplicitSpecHeaders = true;
2922 for (unsigned I = ParamIdx, E = ParamLists.size() - 1; I != E; ++I) {
2923 if (ParamLists[I]->size() == 0)
2924 HasAnyExplicitSpecHeader = true;
2925 else
2926 AllExplicitSpecHeaders = false;
2927 }
2928
2929 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
2930 AllExplicitSpecHeaders ? diag::warn_template_spec_extra_headers
2931 : diag::err_template_spec_extra_headers)
2932 << SourceRange(ParamLists[ParamIdx]->getTemplateLoc(),
2933 ParamLists[ParamLists.size() - 2]->getRAngleLoc());
2934
2935 // If there was a specialization somewhere, such that 'template<>' is
2936 // not required, and there were any 'template<>' headers, note where the
2937 // specialization occurred.
2938 if (ExplicitSpecLoc.isValid() && HasAnyExplicitSpecHeader)
2939 Diag(ExplicitSpecLoc,
2940 diag::note_explicit_template_spec_does_not_need_header)
2941 << NestedTypes.back();
2942
2943 // We have a template parameter list with no corresponding scope, which
2944 // means that the resulting template declaration can't be instantiated
2945 // properly (we'll end up with dependent nodes when we shouldn't).
2946 if (!AllExplicitSpecHeaders)
2947 Invalid = true;
2948 }
2949
2950 // C++ [temp.expl.spec]p16:
2951 // In an explicit specialization declaration for a member of a class
2952 // template or a member template that ap- pears in namespace scope, the
2953 // member template and some of its enclosing class templates may remain
2954 // unspecialized, except that the declaration shall not explicitly
2955 // specialize a class member template if its en- closing class templates
2956 // are not explicitly specialized as well.
2957 if (ParamLists.back()->size() == 0 &&
2958 CheckExplicitSpecialization(ParamLists[ParamIdx]->getSourceRange(),
2959 false))
2960 return nullptr;
2961
2962 // Return the last template parameter list, which corresponds to the
2963 // entity being declared.
2964 return ParamLists.back();
2965}
2966
2967void Sema::NoteAllFoundTemplates(TemplateName Name) {
2968 if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2969 Diag(Template->getLocation(), diag::note_template_declared_here)
2970 << (isa<FunctionTemplateDecl>(Template)
2971 ? 0
2972 : isa<ClassTemplateDecl>(Template)
2973 ? 1
2974 : isa<VarTemplateDecl>(Template)
2975 ? 2
2976 : isa<TypeAliasTemplateDecl>(Template) ? 3 : 4)
2977 << Template->getDeclName();
2978 return;
2979 }
2980
2981 if (OverloadedTemplateStorage *OST = Name.getAsOverloadedTemplate()) {
2982 for (OverloadedTemplateStorage::iterator I = OST->begin(),
2983 IEnd = OST->end();
2984 I != IEnd; ++I)
2985 Diag((*I)->getLocation(), diag::note_template_declared_here)
2986 << 0 << (*I)->getDeclName();
2987
2988 return;
2989 }
2990}
2991
2992static QualType
2993checkBuiltinTemplateIdType(Sema &SemaRef, BuiltinTemplateDecl *BTD,
2994 const SmallVectorImpl<TemplateArgument> &Converted,
2995 SourceLocation TemplateLoc,
2996 TemplateArgumentListInfo &TemplateArgs) {
2997 ASTContext &Context = SemaRef.getASTContext();
2998 switch (BTD->getBuiltinTemplateKind()) {
2999 case BTK__make_integer_seq: {
3000 // Specializations of __make_integer_seq<S, T, N> are treated like
3001 // S<T, 0, ..., N-1>.
3002
3003 // C++14 [inteseq.intseq]p1:
3004 // T shall be an integer type.
3005 if (!Converted[1].getAsType()->isIntegralType(Context)) {
3006 SemaRef.Diag(TemplateArgs[1].getLocation(),
3007 diag::err_integer_sequence_integral_element_type);
3008 return QualType();
3009 }
3010
3011 // C++14 [inteseq.make]p1:
3012 // If N is negative the program is ill-formed.
3013 TemplateArgument NumArgsArg = Converted[2];
3014 llvm::APSInt NumArgs = NumArgsArg.getAsIntegral();
3015 if (NumArgs < 0) {
3016 SemaRef.Diag(TemplateArgs[2].getLocation(),
3017 diag::err_integer_sequence_negative_length);
3018 return QualType();
3019 }
3020
3021 QualType ArgTy = NumArgsArg.getIntegralType();
3022 TemplateArgumentListInfo SyntheticTemplateArgs;
3023 // The type argument gets reused as the first template argument in the
3024 // synthetic template argument list.
3025 SyntheticTemplateArgs.addArgument(TemplateArgs[1]);
3026 // Expand N into 0 ... N-1.
3027 for (llvm::APSInt I(NumArgs.getBitWidth(), NumArgs.isUnsigned());
3028 I < NumArgs; ++I) {
3029 TemplateArgument TA(Context, I, ArgTy);
3030 SyntheticTemplateArgs.addArgument(SemaRef.getTrivialTemplateArgumentLoc(
3031 TA, ArgTy, TemplateArgs[2].getLocation()));
3032 }
3033 // The first template argument will be reused as the template decl that
3034 // our synthetic template arguments will be applied to.
3035 return SemaRef.CheckTemplateIdType(Converted[0].getAsTemplate(),
3036 TemplateLoc, SyntheticTemplateArgs);
3037 }
3038
3039 case BTK__type_pack_element:
3040 // Specializations of
3041 // __type_pack_element<Index, T_1, ..., T_N>
3042 // are treated like T_Index.
3043 assert(Converted.size() == 2 &&((Converted.size() == 2 && "__type_pack_element should be given an index and a parameter pack"
) ? static_cast<void> (0) : __assert_fail ("Converted.size() == 2 && \"__type_pack_element should be given an index and a parameter pack\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3044, __PRETTY_FUNCTION__))
3044 "__type_pack_element should be given an index and a parameter pack")((Converted.size() == 2 && "__type_pack_element should be given an index and a parameter pack"
) ? static_cast<void> (0) : __assert_fail ("Converted.size() == 2 && \"__type_pack_element should be given an index and a parameter pack\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3044, __PRETTY_FUNCTION__))
;
3045
3046 // If the Index is out of bounds, the program is ill-formed.
3047 TemplateArgument IndexArg = Converted[0], Ts = Converted[1];
3048 llvm::APSInt Index = IndexArg.getAsIntegral();
3049 assert(Index >= 0 && "the index used with __type_pack_element should be of "((Index >= 0 && "the index used with __type_pack_element should be of "
"type std::size_t, and hence be non-negative") ? static_cast
<void> (0) : __assert_fail ("Index >= 0 && \"the index used with __type_pack_element should be of \" \"type std::size_t, and hence be non-negative\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3050, __PRETTY_FUNCTION__))
3050 "type std::size_t, and hence be non-negative")((Index >= 0 && "the index used with __type_pack_element should be of "
"type std::size_t, and hence be non-negative") ? static_cast
<void> (0) : __assert_fail ("Index >= 0 && \"the index used with __type_pack_element should be of \" \"type std::size_t, and hence be non-negative\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3050, __PRETTY_FUNCTION__))
;
3051 if (Index >= Ts.pack_size()) {
3052 SemaRef.Diag(TemplateArgs[0].getLocation(),
3053 diag::err_type_pack_element_out_of_bounds);
3054 return QualType();
3055 }
3056
3057 // We simply return the type at index `Index`.
3058 auto Nth = std::next(Ts.pack_begin(), Index.getExtValue());
3059 return Nth->getAsType();
3060 }
3061 llvm_unreachable("unexpected BuiltinTemplateDecl!")::llvm::llvm_unreachable_internal("unexpected BuiltinTemplateDecl!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3061)
;
3062}
3063
3064/// Determine whether this alias template is "enable_if_t".
3065static bool isEnableIfAliasTemplate(TypeAliasTemplateDecl *AliasTemplate) {
3066 return AliasTemplate->getName().equals("enable_if_t");
3067}
3068
3069/// Collect all of the separable terms in the given condition, which
3070/// might be a conjunction.
3071///
3072/// FIXME: The right answer is to convert the logical expression into
3073/// disjunctive normal form, so we can find the first failed term
3074/// within each possible clause.
3075static void collectConjunctionTerms(Expr *Clause,
3076 SmallVectorImpl<Expr *> &Terms) {
3077 if (auto BinOp = dyn_cast<BinaryOperator>(Clause->IgnoreParenImpCasts())) {
3078 if (BinOp->getOpcode() == BO_LAnd) {
3079 collectConjunctionTerms(BinOp->getLHS(), Terms);
3080 collectConjunctionTerms(BinOp->getRHS(), Terms);
3081 }
3082
3083 return;
3084 }
3085
3086 Terms.push_back(Clause);
3087}
3088
3089// The ranges-v3 library uses an odd pattern of a top-level "||" with
3090// a left-hand side that is value-dependent but never true. Identify
3091// the idiom and ignore that term.
3092static Expr *lookThroughRangesV3Condition(Preprocessor &PP, Expr *Cond) {
3093 // Top-level '||'.
3094 auto *BinOp = dyn_cast<BinaryOperator>(Cond->IgnoreParenImpCasts());
3095 if (!BinOp) return Cond;
3096
3097 if (BinOp->getOpcode() != BO_LOr) return Cond;
3098
3099 // With an inner '==' that has a literal on the right-hand side.
3100 Expr *LHS = BinOp->getLHS();
3101 auto *InnerBinOp = dyn_cast<BinaryOperator>(LHS->IgnoreParenImpCasts());
3102 if (!InnerBinOp) return Cond;
3103
3104 if (InnerBinOp->getOpcode() != BO_EQ ||
3105 !isa<IntegerLiteral>(InnerBinOp->getRHS()))
3106 return Cond;
3107
3108 // If the inner binary operation came from a macro expansion named
3109 // CONCEPT_REQUIRES or CONCEPT_REQUIRES_, return the right-hand side
3110 // of the '||', which is the real, user-provided condition.
3111 SourceLocation Loc = InnerBinOp->getExprLoc();
3112 if (!Loc.isMacroID()) return Cond;
3113
3114 StringRef MacroName = PP.getImmediateMacroName(Loc);
3115 if (MacroName == "CONCEPT_REQUIRES" || MacroName == "CONCEPT_REQUIRES_")
3116 return BinOp->getRHS();
3117
3118 return Cond;
3119}
3120
3121namespace {
3122
3123// A PrinterHelper that prints more helpful diagnostics for some sub-expressions
3124// within failing boolean expression, such as substituting template parameters
3125// for actual types.
3126class FailedBooleanConditionPrinterHelper : public PrinterHelper {
3127public:
3128 explicit FailedBooleanConditionPrinterHelper(const PrintingPolicy &P)
3129 : Policy(P) {}
3130
3131 bool handledStmt(Stmt *E, raw_ostream &OS) override {
3132 const auto *DR = dyn_cast<DeclRefExpr>(E);
3133 if (DR && DR->getQualifier()) {
3134 // If this is a qualified name, expand the template arguments in nested
3135 // qualifiers.
3136 DR->getQualifier()->print(OS, Policy, true);
3137 // Then print the decl itself.
3138 const ValueDecl *VD = DR->getDecl();
3139 OS << VD->getName();
3140 if (const auto *IV = dyn_cast<VarTemplateSpecializationDecl>(VD)) {
3141 // This is a template variable, print the expanded template arguments.
3142 printTemplateArgumentList(OS, IV->getTemplateArgs().asArray(), Policy);
3143 }
3144 return true;
3145 }
3146 return false;
3147 }
3148
3149private:
3150 const PrintingPolicy Policy;
3151};
3152
3153} // end anonymous namespace
3154
3155std::pair<Expr *, std::string>
3156Sema::findFailedBooleanCondition(Expr *Cond) {
3157 Cond = lookThroughRangesV3Condition(PP, Cond);
3158
3159 // Separate out all of the terms in a conjunction.
3160 SmallVector<Expr *, 4> Terms;
3161 collectConjunctionTerms(Cond, Terms);
3162
3163 // Determine which term failed.
3164 Expr *FailedCond = nullptr;
3165 for (Expr *Term : Terms) {
3166 Expr *TermAsWritten = Term->IgnoreParenImpCasts();
3167
3168 // Literals are uninteresting.
3169 if (isa<CXXBoolLiteralExpr>(TermAsWritten) ||
3170 isa<IntegerLiteral>(TermAsWritten))
3171 continue;
3172
3173 // The initialization of the parameter from the argument is
3174 // a constant-evaluated context.
3175 EnterExpressionEvaluationContext ConstantEvaluated(
3176 *this, Sema::ExpressionEvaluationContext::ConstantEvaluated);
3177
3178 bool Succeeded;
3179 if (Term->EvaluateAsBooleanCondition(Succeeded, Context) &&
3180 !Succeeded) {
3181 FailedCond = TermAsWritten;
3182 break;
3183 }
3184 }
3185 if (!FailedCond)
3186 FailedCond = Cond->IgnoreParenImpCasts();
3187
3188 std::string Description;
3189 {
3190 llvm::raw_string_ostream Out(Description);
3191 PrintingPolicy Policy = getPrintingPolicy();
3192 Policy.PrintCanonicalTypes = true;
3193 FailedBooleanConditionPrinterHelper Helper(Policy);
3194 FailedCond->printPretty(Out, &Helper, Policy, 0, "\n", nullptr);
3195 }
3196 return { FailedCond, Description };
3197}
3198
3199QualType Sema::CheckTemplateIdType(TemplateName Name,
3200 SourceLocation TemplateLoc,
3201 TemplateArgumentListInfo &TemplateArgs) {
3202 DependentTemplateName *DTN
3203 = Name.getUnderlying().getAsDependentTemplateName();
3204 if (DTN && DTN->isIdentifier())
3205 // When building a template-id where the template-name is dependent,
3206 // assume the template is a type template. Either our assumption is
3207 // correct, or the code is ill-formed and will be diagnosed when the
3208 // dependent name is substituted.
3209 return Context.getDependentTemplateSpecializationType(ETK_None,
3210 DTN->getQualifier(),
3211 DTN->getIdentifier(),
3212 TemplateArgs);
3213
3214 TemplateDecl *Template = Name.getAsTemplateDecl();
3215 if (!Template || isa<FunctionTemplateDecl>(Template) ||
3216 isa<VarTemplateDecl>(Template) ||
3217 isa<ConceptDecl>(Template)) {
3218 // We might have a substituted template template parameter pack. If so,
3219 // build a template specialization type for it.
3220 if (Name.getAsSubstTemplateTemplateParmPack())
3221 return Context.getTemplateSpecializationType(Name, TemplateArgs);
3222
3223 Diag(TemplateLoc, diag::err_template_id_not_a_type)
3224 << Name;
3225 NoteAllFoundTemplates(Name);
3226 return QualType();
3227 }
3228
3229 // Check that the template argument list is well-formed for this
3230 // template.
3231 SmallVector<TemplateArgument, 4> Converted;
3232 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
3233 false, Converted))
3234 return QualType();
3235
3236 QualType CanonType;
3237
3238 bool InstantiationDependent = false;
3239 if (TypeAliasTemplateDecl *AliasTemplate =
3240 dyn_cast<TypeAliasTemplateDecl>(Template)) {
3241 // Find the canonical type for this type alias template specialization.
3242 TypeAliasDecl *Pattern = AliasTemplate->getTemplatedDecl();
3243 if (Pattern->isInvalidDecl())
3244 return QualType();
3245
3246 TemplateArgumentList StackTemplateArgs(TemplateArgumentList::OnStack,
3247 Converted);
3248
3249 // Only substitute for the innermost template argument list.
3250 MultiLevelTemplateArgumentList TemplateArgLists;
3251 TemplateArgLists.addOuterTemplateArguments(&StackTemplateArgs);
3252 unsigned Depth = AliasTemplate->getTemplateParameters()->getDepth();
3253 for (unsigned I = 0; I < Depth; ++I)
3254 TemplateArgLists.addOuterTemplateArguments(None);
3255
3256 LocalInstantiationScope Scope(*this);
3257 InstantiatingTemplate Inst(*this, TemplateLoc, Template);
3258 if (Inst.isInvalid())
3259 return QualType();
3260
3261 CanonType = SubstType(Pattern->getUnderlyingType(),
3262 TemplateArgLists, AliasTemplate->getLocation(),
3263 AliasTemplate->getDeclName());
3264 if (CanonType.isNull()) {
3265 // If this was enable_if and we failed to find the nested type
3266 // within enable_if in a SFINAE context, dig out the specific
3267 // enable_if condition that failed and present that instead.
3268 if (isEnableIfAliasTemplate(AliasTemplate)) {
3269 if (auto DeductionInfo = isSFINAEContext()) {
3270 if (*DeductionInfo &&
3271 (*DeductionInfo)->hasSFINAEDiagnostic() &&
3272 (*DeductionInfo)->peekSFINAEDiagnostic().second.getDiagID() ==
3273 diag::err_typename_nested_not_found_enable_if &&
3274 TemplateArgs[0].getArgument().getKind()
3275 == TemplateArgument::Expression) {
3276 Expr *FailedCond;
3277 std::string FailedDescription;
3278 std::tie(FailedCond, FailedDescription) =
3279 findFailedBooleanCondition(TemplateArgs[0].getSourceExpression());
3280
3281 // Remove the old SFINAE diagnostic.
3282 PartialDiagnosticAt OldDiag =
3283 {SourceLocation(), PartialDiagnostic::NullDiagnostic()};
3284 (*DeductionInfo)->takeSFINAEDiagnostic(OldDiag);
3285
3286 // Add a new SFINAE diagnostic specifying which condition
3287 // failed.
3288 (*DeductionInfo)->addSFINAEDiagnostic(
3289 OldDiag.first,
3290 PDiag(diag::err_typename_nested_not_found_requirement)
3291 << FailedDescription
3292 << FailedCond->getSourceRange());
3293 }
3294 }
3295 }
3296
3297 return QualType();
3298 }
3299 } else if (Name.isDependent() ||
3300 TemplateSpecializationType::anyDependentTemplateArguments(
3301 TemplateArgs, InstantiationDependent)) {
3302 // This class template specialization is a dependent
3303 // type. Therefore, its canonical type is another class template
3304 // specialization type that contains all of the converted
3305 // arguments in canonical form. This ensures that, e.g., A<T> and
3306 // A<T, T> have identical types when A is declared as:
3307 //
3308 // template<typename T, typename U = T> struct A;
3309 CanonType = Context.getCanonicalTemplateSpecializationType(Name, Converted);
3310
3311 // This might work out to be a current instantiation, in which
3312 // case the canonical type needs to be the InjectedClassNameType.
3313 //
3314 // TODO: in theory this could be a simple hashtable lookup; most
3315 // changes to CurContext don't change the set of current
3316 // instantiations.
3317 if (isa<ClassTemplateDecl>(Template)) {
3318 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
3319 // If we get out to a namespace, we're done.
3320 if (Ctx->isFileContext()) break;
3321
3322 // If this isn't a record, keep looking.
3323 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
3324 if (!Record) continue;
3325
3326 // Look for one of the two cases with InjectedClassNameTypes
3327 // and check whether it's the same template.
3328 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
3329 !Record->getDescribedClassTemplate())
3330 continue;
3331
3332 // Fetch the injected class name type and check whether its
3333 // injected type is equal to the type we just built.
3334 QualType ICNT = Context.getTypeDeclType(Record);
3335 QualType Injected = cast<InjectedClassNameType>(ICNT)
3336 ->getInjectedSpecializationType();
3337
3338 if (CanonType != Injected->getCanonicalTypeInternal())
3339 continue;
3340
3341 // If so, the canonical type of this TST is the injected
3342 // class name type of the record we just found.
3343 assert(ICNT.isCanonical())((ICNT.isCanonical()) ? static_cast<void> (0) : __assert_fail
("ICNT.isCanonical()", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3343, __PRETTY_FUNCTION__))
;
3344 CanonType = ICNT;
3345 break;
3346 }
3347 }
3348 } else if (ClassTemplateDecl *ClassTemplate
3349 = dyn_cast<ClassTemplateDecl>(Template)) {
3350 // Find the class template specialization declaration that
3351 // corresponds to these arguments.
3352 void *InsertPos = nullptr;
3353 ClassTemplateSpecializationDecl *Decl
3354 = ClassTemplate->findSpecialization(Converted, InsertPos);
3355 if (!Decl) {
3356 // This is the first time we have referenced this class template
3357 // specialization. Create the canonical declaration and add it to
3358 // the set of specializations.
3359 Decl = ClassTemplateSpecializationDecl::Create(
3360 Context, ClassTemplate->getTemplatedDecl()->getTagKind(),
3361 ClassTemplate->getDeclContext(),
3362 ClassTemplate->getTemplatedDecl()->getBeginLoc(),
3363 ClassTemplate->getLocation(), ClassTemplate, Converted, nullptr);
3364 ClassTemplate->AddSpecialization(Decl, InsertPos);
3365 if (ClassTemplate->isOutOfLine())
3366 Decl->setLexicalDeclContext(ClassTemplate->getLexicalDeclContext());
3367 }
3368
3369 if (Decl->getSpecializationKind() == TSK_Undeclared) {
3370 MultiLevelTemplateArgumentList TemplateArgLists;
3371 TemplateArgLists.addOuterTemplateArguments(Converted);
3372 InstantiateAttrsForDecl(TemplateArgLists, ClassTemplate->getTemplatedDecl(),
3373 Decl);
3374 }
3375
3376 // Diagnose uses of this specialization.
3377 (void)DiagnoseUseOfDecl(Decl, TemplateLoc);
3378
3379 CanonType = Context.getTypeDeclType(Decl);
3380 assert(isa<RecordType>(CanonType) &&((isa<RecordType>(CanonType) && "type of non-dependent specialization is not a RecordType"
) ? static_cast<void> (0) : __assert_fail ("isa<RecordType>(CanonType) && \"type of non-dependent specialization is not a RecordType\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3381, __PRETTY_FUNCTION__))
3381 "type of non-dependent specialization is not a RecordType")((isa<RecordType>(CanonType) && "type of non-dependent specialization is not a RecordType"
) ? static_cast<void> (0) : __assert_fail ("isa<RecordType>(CanonType) && \"type of non-dependent specialization is not a RecordType\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3381, __PRETTY_FUNCTION__))
;
3382 } else if (auto *BTD = dyn_cast<BuiltinTemplateDecl>(Template)) {
3383 CanonType = checkBuiltinTemplateIdType(*this, BTD, Converted, TemplateLoc,
3384 TemplateArgs);
3385 }
3386
3387 // Build the fully-sugared type for this class template
3388 // specialization, which refers back to the class template
3389 // specialization we created or found.
3390 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
3391}
3392
3393void Sema::ActOnUndeclaredTypeTemplateName(Scope *S, TemplateTy &ParsedName,
3394 TemplateNameKind &TNK,
3395 SourceLocation NameLoc,
3396 IdentifierInfo *&II) {
3397 assert(TNK == TNK_Undeclared_template && "not an undeclared template name")((TNK == TNK_Undeclared_template && "not an undeclared template name"
) ? static_cast<void> (0) : __assert_fail ("TNK == TNK_Undeclared_template && \"not an undeclared template name\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3397, __PRETTY_FUNCTION__))
;
3398
3399 TemplateName Name = ParsedName.get();
3400 auto *ATN = Name.getAsAssumedTemplateName();
3401 assert(ATN && "not an assumed template name")((ATN && "not an assumed template name") ? static_cast
<void> (0) : __assert_fail ("ATN && \"not an assumed template name\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3401, __PRETTY_FUNCTION__))
;
3402 II = ATN->getDeclName().getAsIdentifierInfo();
3403
3404 if (!resolveAssumedTemplateNameAsType(S, Name, NameLoc, /*Diagnose*/false)) {
3405 // Resolved to a type template name.
3406 ParsedName = TemplateTy::make(Name);
3407 TNK = TNK_Type_template;
3408 }
3409}
3410
3411bool Sema::resolveAssumedTemplateNameAsType(Scope *S, TemplateName &Name,
3412 SourceLocation NameLoc,
3413 bool Diagnose) {
3414 // We assumed this undeclared identifier to be an (ADL-only) function
3415 // template name, but it was used in a context where a type was required.
3416 // Try to typo-correct it now.
3417 AssumedTemplateStorage *ATN = Name.getAsAssumedTemplateName();
3418 assert(ATN && "not an assumed template name")((ATN && "not an assumed template name") ? static_cast
<void> (0) : __assert_fail ("ATN && \"not an assumed template name\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3418, __PRETTY_FUNCTION__))
;
3419
3420 LookupResult R(*this, ATN->getDeclName(), NameLoc, LookupOrdinaryName);
3421 struct CandidateCallback : CorrectionCandidateCallback {
3422 bool ValidateCandidate(const TypoCorrection &TC) override {
3423 return TC.getCorrectionDecl() &&
3424 getAsTypeTemplateDecl(TC.getCorrectionDecl());
3425 }
3426 std::unique_ptr<CorrectionCandidateCallback> clone() override {
3427 return std::make_unique<CandidateCallback>(*this);
3428 }
3429 } FilterCCC;
3430
3431 TypoCorrection Corrected =
3432 CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S, nullptr,
3433 FilterCCC, CTK_ErrorRecovery);
3434 if (Corrected && Corrected.getFoundDecl()) {
3435 diagnoseTypo(Corrected, PDiag(diag::err_no_template_suggest)
3436 << ATN->getDeclName());
3437 Name = TemplateName(Corrected.getCorrectionDeclAs<TemplateDecl>());
3438 return false;
3439 }
3440
3441 if (Diagnose)
3442 Diag(R.getNameLoc(), diag::err_no_template) << R.getLookupName();
3443 return true;
3444}
3445
3446TypeResult Sema::ActOnTemplateIdType(
3447 Scope *S, CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
3448 TemplateTy TemplateD, IdentifierInfo *TemplateII,
3449 SourceLocation TemplateIILoc, SourceLocation LAngleLoc,
3450 ASTTemplateArgsPtr TemplateArgsIn, SourceLocation RAngleLoc,
3451 bool IsCtorOrDtorName, bool IsClassName) {
3452 if (SS.isInvalid())
3453 return true;
3454
3455 if (!IsCtorOrDtorName && !IsClassName && SS.isSet()) {
3456 DeclContext *LookupCtx = computeDeclContext(SS, /*EnteringContext*/false);
3457
3458 // C++ [temp.res]p3:
3459 // A qualified-id that refers to a type and in which the
3460 // nested-name-specifier depends on a template-parameter (14.6.2)
3461 // shall be prefixed by the keyword typename to indicate that the
3462 // qualified-id denotes a type, forming an
3463 // elaborated-type-specifier (7.1.5.3).
3464 if (!LookupCtx && isDependentScopeSpecifier(SS)) {
3465 Diag(SS.getBeginLoc(), diag::err_typename_missing_template)
3466 << SS.getScopeRep() << TemplateII->getName();
3467 // Recover as if 'typename' were specified.
3468 // FIXME: This is not quite correct recovery as we don't transform SS
3469 // into the corresponding dependent form (and we don't diagnose missing
3470 // 'template' keywords within SS as a result).
3471 return ActOnTypenameType(nullptr, SourceLocation(), SS, TemplateKWLoc,
3472 TemplateD, TemplateII, TemplateIILoc, LAngleLoc,
3473 TemplateArgsIn, RAngleLoc);
3474 }
3475
3476 // Per C++ [class.qual]p2, if the template-id was an injected-class-name,
3477 // it's not actually allowed to be used as a type in most cases. Because
3478 // we annotate it before we know whether it's valid, we have to check for
3479 // this case here.
3480 auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx);
3481 if (LookupRD && LookupRD->getIdentifier() == TemplateII) {
3482 Diag(TemplateIILoc,
3483 TemplateKWLoc.isInvalid()
3484 ? diag::err_out_of_line_qualified_id_type_names_constructor
3485 : diag::ext_out_of_line_qualified_id_type_names_constructor)
3486 << TemplateII << 0 /*injected-class-name used as template name*/
3487 << 1 /*if any keyword was present, it was 'template'*/;
3488 }
3489 }
3490
3491 TemplateName Template = TemplateD.get();
3492 if (Template.getAsAssumedTemplateName() &&
3493 resolveAssumedTemplateNameAsType(S, Template, TemplateIILoc))
3494 return true;
3495
3496 // Translate the parser's template argument list in our AST format.
3497 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
3498 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
3499
3500 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
3501 QualType T
3502 = Context.getDependentTemplateSpecializationType(ETK_None,
3503 DTN->getQualifier(),
3504 DTN->getIdentifier(),
3505 TemplateArgs);
3506 // Build type-source information.
3507 TypeLocBuilder TLB;
3508 DependentTemplateSpecializationTypeLoc SpecTL
3509 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
3510 SpecTL.setElaboratedKeywordLoc(SourceLocation());
3511 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
3512 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
3513 SpecTL.setTemplateNameLoc(TemplateIILoc);
3514 SpecTL.setLAngleLoc(LAngleLoc);
3515 SpecTL.setRAngleLoc(RAngleLoc);
3516 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
3517 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
3518 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
3519 }
3520
3521 QualType Result = CheckTemplateIdType(Template, TemplateIILoc, TemplateArgs);
3522 if (Result.isNull())
3523 return true;
3524
3525 // Build type-source information.
3526 TypeLocBuilder TLB;
3527 TemplateSpecializationTypeLoc SpecTL
3528 = TLB.push<TemplateSpecializationTypeLoc>(Result);
3529 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
3530 SpecTL.setTemplateNameLoc(TemplateIILoc);
3531 SpecTL.setLAngleLoc(LAngleLoc);
3532 SpecTL.setRAngleLoc(RAngleLoc);
3533 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
3534 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
3535
3536 // NOTE: avoid constructing an ElaboratedTypeLoc if this is a
3537 // constructor or destructor name (in such a case, the scope specifier
3538 // will be attached to the enclosing Decl or Expr node).
3539 if (SS.isNotEmpty() && !IsCtorOrDtorName) {
3540 // Create an elaborated-type-specifier containing the nested-name-specifier.
3541 Result = Context.getElaboratedType(ETK_None, SS.getScopeRep(), Result);
3542 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
3543 ElabTL.setElaboratedKeywordLoc(SourceLocation());
3544 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
3545 }
3546
3547 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
3548}
3549
3550TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
3551 TypeSpecifierType TagSpec,
3552 SourceLocation TagLoc,
3553 CXXScopeSpec &SS,
3554 SourceLocation TemplateKWLoc,
3555 TemplateTy TemplateD,
3556 SourceLocation TemplateLoc,
3557 SourceLocation LAngleLoc,
3558 ASTTemplateArgsPtr TemplateArgsIn,
3559 SourceLocation RAngleLoc) {
3560 TemplateName Template = TemplateD.get();
3561
3562 // Translate the parser's template argument list in our AST format.
3563 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
3564 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
3565
3566 // Determine the tag kind
3567 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
3568 ElaboratedTypeKeyword Keyword
3569 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
3570
3571 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
3572 QualType T = Context.getDependentTemplateSpecializationType(Keyword,
3573 DTN->getQualifier(),
3574 DTN->getIdentifier(),
3575 TemplateArgs);
3576
3577 // Build type-source information.
3578 TypeLocBuilder TLB;
3579 DependentTemplateSpecializationTypeLoc SpecTL
3580 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
3581 SpecTL.setElaboratedKeywordLoc(TagLoc);
3582 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
3583 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
3584 SpecTL.setTemplateNameLoc(TemplateLoc);
3585 SpecTL.setLAngleLoc(LAngleLoc);
3586 SpecTL.setRAngleLoc(RAngleLoc);
3587 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
3588 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
3589 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
3590 }
3591
3592 if (TypeAliasTemplateDecl *TAT =
3593 dyn_cast_or_null<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) {
3594 // C++0x [dcl.type.elab]p2:
3595 // If the identifier resolves to a typedef-name or the simple-template-id
3596 // resolves to an alias template specialization, the
3597 // elaborated-type-specifier is ill-formed.
3598 Diag(TemplateLoc, diag::err_tag_reference_non_tag)
3599 << TAT << NTK_TypeAliasTemplate << TagKind;
3600 Diag(TAT->getLocation(), diag::note_declared_at);
3601 }
3602
3603 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
3604 if (Result.isNull())
3605 return TypeResult(true);
3606
3607 // Check the tag kind
3608 if (const RecordType *RT = Result->getAs<RecordType>()) {
3609 RecordDecl *D = RT->getDecl();
3610
3611 IdentifierInfo *Id = D->getIdentifier();
3612 assert(Id && "templated class must have an identifier")((Id && "templated class must have an identifier") ? static_cast
<void> (0) : __assert_fail ("Id && \"templated class must have an identifier\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3612, __PRETTY_FUNCTION__))
;
3613
3614 if (!isAcceptableTagRedeclaration(D, TagKind, TUK == TUK_Definition,
3615 TagLoc, Id)) {
3616 Diag(TagLoc, diag::err_use_with_wrong_tag)
3617 << Result
3618 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
3619 Diag(D->getLocation(), diag::note_previous_use);
3620 }
3621 }
3622
3623 // Provide source-location information for the template specialization.
3624 TypeLocBuilder TLB;
3625 TemplateSpecializationTypeLoc SpecTL
3626 = TLB.push<TemplateSpecializationTypeLoc>(Result);
3627 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
3628 SpecTL.setTemplateNameLoc(TemplateLoc);
3629 SpecTL.setLAngleLoc(LAngleLoc);
3630 SpecTL.setRAngleLoc(RAngleLoc);
3631 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
3632 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
3633
3634 // Construct an elaborated type containing the nested-name-specifier (if any)
3635 // and tag keyword.
3636 Result = Context.getElaboratedType(Keyword, SS.getScopeRep(), Result);
3637 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
3638 ElabTL.setElaboratedKeywordLoc(TagLoc);
3639 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
3640 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
3641}
3642
3643static bool CheckTemplateSpecializationScope(Sema &S, NamedDecl *Specialized,
3644 NamedDecl *PrevDecl,
3645 SourceLocation Loc,
3646 bool IsPartialSpecialization);
3647
3648static TemplateSpecializationKind getTemplateSpecializationKind(Decl *D);
3649
3650static bool isTemplateArgumentTemplateParameter(
3651 const TemplateArgument &Arg, unsigned Depth, unsigned Index) {
3652 switch (Arg.getKind()) {
3653 case TemplateArgument::Null:
3654 case TemplateArgument::NullPtr:
3655 case TemplateArgument::Integral:
3656 case TemplateArgument::Declaration:
3657 case TemplateArgument::Pack:
3658 case TemplateArgument::TemplateExpansion:
3659 return false;
3660
3661 case TemplateArgument::Type: {
3662 QualType Type = Arg.getAsType();
3663 const TemplateTypeParmType *TPT =
3664 Arg.getAsType()->getAs<TemplateTypeParmType>();
3665 return TPT && !Type.hasQualifiers() &&
3666 TPT->getDepth() == Depth && TPT->getIndex() == Index;
3667 }
3668
3669 case TemplateArgument::Expression: {
3670 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg.getAsExpr());
3671 if (!DRE || !DRE->getDecl())
3672 return false;
3673 const NonTypeTemplateParmDecl *NTTP =
3674 dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
3675 return NTTP && NTTP->getDepth() == Depth && NTTP->getIndex() == Index;
3676 }
3677
3678 case TemplateArgument::Template:
3679 const TemplateTemplateParmDecl *TTP =
3680 dyn_cast_or_null<TemplateTemplateParmDecl>(
3681 Arg.getAsTemplateOrTemplatePattern().getAsTemplateDecl());
3682 return TTP && TTP->getDepth() == Depth && TTP->getIndex() == Index;
3683 }
3684 llvm_unreachable("unexpected kind of template argument")::llvm::llvm_unreachable_internal("unexpected kind of template argument"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3684)
;
3685}
3686
3687static bool isSameAsPrimaryTemplate(TemplateParameterList *Params,
3688 ArrayRef<TemplateArgument> Args) {
3689 if (Params->size() != Args.size())
3690 return false;
3691
3692 unsigned Depth = Params->getDepth();
3693
3694 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
3695 TemplateArgument Arg = Args[I];
3696
3697 // If the parameter is a pack expansion, the argument must be a pack
3698 // whose only element is a pack expansion.
3699 if (Params->getParam(I)->isParameterPack()) {
3700 if (Arg.getKind() != TemplateArgument::Pack || Arg.pack_size() != 1 ||
3701 !Arg.pack_begin()->isPackExpansion())
3702 return false;
3703 Arg = Arg.pack_begin()->getPackExpansionPattern();
3704 }
3705
3706 if (!isTemplateArgumentTemplateParameter(Arg, Depth, I))
3707 return false;
3708 }
3709
3710 return true;
3711}
3712
3713/// Convert the parser's template argument list representation into our form.
3714static TemplateArgumentListInfo
3715makeTemplateArgumentListInfo(Sema &S, TemplateIdAnnotation &TemplateId) {
3716 TemplateArgumentListInfo TemplateArgs(TemplateId.LAngleLoc,
3717 TemplateId.RAngleLoc);
3718 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId.getTemplateArgs(),
3719 TemplateId.NumArgs);
3720 S.translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
3721 return TemplateArgs;
3722}
3723
3724template<typename PartialSpecDecl>
3725static void checkMoreSpecializedThanPrimary(Sema &S, PartialSpecDecl *Partial) {
3726 if (Partial->getDeclContext()->isDependentContext())
3727 return;
3728
3729 // FIXME: Get the TDK from deduction in order to provide better diagnostics
3730 // for non-substitution-failure issues?
3731 TemplateDeductionInfo Info(Partial->getLocation());
3732 if (S.isMoreSpecializedThanPrimary(Partial, Info))
3733 return;
3734
3735 auto *Template = Partial->getSpecializedTemplate();
3736 S.Diag(Partial->getLocation(),
3737 diag::ext_partial_spec_not_more_specialized_than_primary)
3738 << isa<VarTemplateDecl>(Template);
3739
3740 if (Info.hasSFINAEDiagnostic()) {
3741 PartialDiagnosticAt Diag = {SourceLocation(),
3742 PartialDiagnostic::NullDiagnostic()};
3743 Info.takeSFINAEDiagnostic(Diag);
3744 SmallString<128> SFINAEArgString;
3745 Diag.second.EmitToString(S.getDiagnostics(), SFINAEArgString);
3746 S.Diag(Diag.first,
3747 diag::note_partial_spec_not_more_specialized_than_primary)
3748 << SFINAEArgString;
3749 }
3750
3751 S.Diag(Template->getLocation(), diag::note_template_decl_here);
3752}
3753
3754static void
3755noteNonDeducibleParameters(Sema &S, TemplateParameterList *TemplateParams,
3756 const llvm::SmallBitVector &DeducibleParams) {
3757 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
3758 if (!DeducibleParams[I]) {
3759 NamedDecl *Param = TemplateParams->getParam(I);
3760 if (Param->getDeclName())
3761 S.Diag(Param->getLocation(), diag::note_non_deducible_parameter)
3762 << Param->getDeclName();
3763 else
3764 S.Diag(Param->getLocation(), diag::note_non_deducible_parameter)
3765 << "(anonymous)";
3766 }
3767 }
3768}
3769
3770
3771template<typename PartialSpecDecl>
3772static void checkTemplatePartialSpecialization(Sema &S,
3773 PartialSpecDecl *Partial) {
3774 // C++1z [temp.class.spec]p8: (DR1495)
3775 // - The specialization shall be more specialized than the primary
3776 // template (14.5.5.2).
3777 checkMoreSpecializedThanPrimary(S, Partial);
3778
3779 // C++ [temp.class.spec]p8: (DR1315)
3780 // - Each template-parameter shall appear at least once in the
3781 // template-id outside a non-deduced context.
3782 // C++1z [temp.class.spec.match]p3 (P0127R2)
3783 // If the template arguments of a partial specialization cannot be
3784 // deduced because of the structure of its template-parameter-list
3785 // and the template-id, the program is ill-formed.
3786 auto *TemplateParams = Partial->getTemplateParameters();
3787 llvm::SmallBitVector DeducibleParams(TemplateParams->size());
3788 S.MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
3789 TemplateParams->getDepth(), DeducibleParams);
3790
3791 if (!DeducibleParams.all()) {
3792 unsigned NumNonDeducible = DeducibleParams.size() - DeducibleParams.count();
3793 S.Diag(Partial->getLocation(), diag::ext_partial_specs_not_deducible)
3794 << isa<VarTemplatePartialSpecializationDecl>(Partial)
3795 << (NumNonDeducible > 1)
3796 << SourceRange(Partial->getLocation(),
3797 Partial->getTemplateArgsAsWritten()->RAngleLoc);
3798 noteNonDeducibleParameters(S, TemplateParams, DeducibleParams);
3799 }
3800}
3801
3802void Sema::CheckTemplatePartialSpecialization(
3803 ClassTemplatePartialSpecializationDecl *Partial) {
3804 checkTemplatePartialSpecialization(*this, Partial);
3805}
3806
3807void Sema::CheckTemplatePartialSpecialization(
3808 VarTemplatePartialSpecializationDecl *Partial) {
3809 checkTemplatePartialSpecialization(*this, Partial);
3810}
3811
3812void Sema::CheckDeductionGuideTemplate(FunctionTemplateDecl *TD) {
3813 // C++1z [temp.param]p11:
3814 // A template parameter of a deduction guide template that does not have a
3815 // default-argument shall be deducible from the parameter-type-list of the
3816 // deduction guide template.
3817 auto *TemplateParams = TD->getTemplateParameters();
3818 llvm::SmallBitVector DeducibleParams(TemplateParams->size());
3819 MarkDeducedTemplateParameters(TD, DeducibleParams);
3820 for (unsigned I = 0; I != TemplateParams->size(); ++I) {
3821 // A parameter pack is deducible (to an empty pack).
3822 auto *Param = TemplateParams->getParam(I);
3823 if (Param->isParameterPack() || hasVisibleDefaultArgument(Param))
3824 DeducibleParams[I] = true;
3825 }
3826
3827 if (!DeducibleParams.all()) {
3828 unsigned NumNonDeducible = DeducibleParams.size() - DeducibleParams.count();
3829 Diag(TD->getLocation(), diag::err_deduction_guide_template_not_deducible)
3830 << (NumNonDeducible > 1);
3831 noteNonDeducibleParameters(*this, TemplateParams, DeducibleParams);
3832 }
3833}
3834
3835DeclResult Sema::ActOnVarTemplateSpecialization(
3836 Scope *S, Declarator &D, TypeSourceInfo *DI, SourceLocation TemplateKWLoc,
3837 TemplateParameterList *TemplateParams, StorageClass SC,
3838 bool IsPartialSpecialization) {
3839 // D must be variable template id.
3840 assert(D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId &&((D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId &&
"Variable template specialization is declared with a template it."
) ? static_cast<void> (0) : __assert_fail ("D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId && \"Variable template specialization is declared with a template it.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3841, __PRETTY_FUNCTION__))
3841 "Variable template specialization is declared with a template it.")((D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId &&
"Variable template specialization is declared with a template it."
) ? static_cast<void> (0) : __assert_fail ("D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId && \"Variable template specialization is declared with a template it.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 3841, __PRETTY_FUNCTION__))
;
3842
3843 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
3844 TemplateArgumentListInfo TemplateArgs =
3845 makeTemplateArgumentListInfo(*this, *TemplateId);
3846 SourceLocation TemplateNameLoc = D.getIdentifierLoc();
3847 SourceLocation LAngleLoc = TemplateId->LAngleLoc;
3848 SourceLocation RAngleLoc = TemplateId->RAngleLoc;
3849
3850 TemplateName Name = TemplateId->Template.get();
3851
3852 // The template-id must name a variable template.
3853 VarTemplateDecl *VarTemplate =
3854 dyn_cast_or_null<VarTemplateDecl>(Name.getAsTemplateDecl());
3855 if (!VarTemplate) {
3856 NamedDecl *FnTemplate;
3857 if (auto *OTS = Name.getAsOverloadedTemplate())
3858 FnTemplate = *OTS->begin();
3859 else
3860 FnTemplate = dyn_cast_or_null<FunctionTemplateDecl>(Name.getAsTemplateDecl());
3861 if (FnTemplate)
3862 return Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template_but_method)
3863 << FnTemplate->getDeclName();
3864 return Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template)
3865 << IsPartialSpecialization;
3866 }
3867
3868 // Check for unexpanded parameter packs in any of the template arguments.
3869 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
3870 if (DiagnoseUnexpandedParameterPack(TemplateArgs[I],
3871 UPPC_PartialSpecialization))
3872 return true;
3873
3874 // Check that the template argument list is well-formed for this
3875 // template.
3876 SmallVector<TemplateArgument, 4> Converted;
3877 if (CheckTemplateArgumentList(VarTemplate, TemplateNameLoc, TemplateArgs,
3878 false, Converted))
3879 return true;
3880
3881 // Find the variable template (partial) specialization declaration that
3882 // corresponds to these arguments.
3883 if (IsPartialSpecialization) {
3884 if (CheckTemplatePartialSpecializationArgs(TemplateNameLoc, VarTemplate,
3885 TemplateArgs.size(), Converted))
3886 return true;
3887
3888 // FIXME: Move these checks to CheckTemplatePartialSpecializationArgs so we
3889 // also do them during instantiation.
3890 bool InstantiationDependent;
3891 if (!Name.isDependent() &&
3892 !TemplateSpecializationType::anyDependentTemplateArguments(
3893 TemplateArgs.arguments(),
3894 InstantiationDependent)) {
3895 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
3896 << VarTemplate->getDeclName();
3897 IsPartialSpecialization = false;
3898 }
3899
3900 if (isSameAsPrimaryTemplate(VarTemplate->getTemplateParameters(),
3901 Converted)) {
3902 // C++ [temp.class.spec]p9b3:
3903 //
3904 // -- The argument list of the specialization shall not be identical
3905 // to the implicit argument list of the primary template.
3906 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
3907 << /*variable template*/ 1
3908 << /*is definition*/(SC != SC_Extern && !CurContext->isRecord())
3909 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
3910 // FIXME: Recover from this by treating the declaration as a redeclaration
3911 // of the primary template.
3912 return true;
3913 }
3914 }
3915
3916 void *InsertPos = nullptr;
3917 VarTemplateSpecializationDecl *PrevDecl = nullptr;
3918
3919 if (IsPartialSpecialization)
3920 // FIXME: Template parameter list matters too
3921 PrevDecl = VarTemplate->findPartialSpecialization(Converted, InsertPos);
3922 else
3923 PrevDecl = VarTemplate->findSpecialization(Converted, InsertPos);
3924
3925 VarTemplateSpecializationDecl *Specialization = nullptr;
3926
3927 // Check whether we can declare a variable template specialization in
3928 // the current scope.
3929 if (CheckTemplateSpecializationScope(*this, VarTemplate, PrevDecl,
3930 TemplateNameLoc,
3931 IsPartialSpecialization))
3932 return true;
3933
3934 if (PrevDecl && PrevDecl->getSpecializationKind() == TSK_Undeclared) {
3935 // Since the only prior variable template specialization with these
3936 // arguments was referenced but not declared, reuse that
3937 // declaration node as our own, updating its source location and
3938 // the list of outer template parameters to reflect our new declaration.
3939 Specialization = PrevDecl;
3940 Specialization->setLocation(TemplateNameLoc);
3941 PrevDecl = nullptr;
3942 } else if (IsPartialSpecialization) {
3943 // Create a new class template partial specialization declaration node.
3944 VarTemplatePartialSpecializationDecl *PrevPartial =
3945 cast_or_null<VarTemplatePartialSpecializationDecl>(PrevDecl);
3946 VarTemplatePartialSpecializationDecl *Partial =
3947 VarTemplatePartialSpecializationDecl::Create(
3948 Context, VarTemplate->getDeclContext(), TemplateKWLoc,
3949 TemplateNameLoc, TemplateParams, VarTemplate, DI->getType(), DI, SC,
3950 Converted, TemplateArgs);
3951
3952 if (!PrevPartial)
3953 VarTemplate->AddPartialSpecialization(Partial, InsertPos);
3954 Specialization = Partial;
3955
3956 // If we are providing an explicit specialization of a member variable
3957 // template specialization, make a note of that.
3958 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
3959 PrevPartial->setMemberSpecialization();
3960
3961 CheckTemplatePartialSpecialization(Partial);
3962 } else {
3963 // Create a new class template specialization declaration node for
3964 // this explicit specialization or friend declaration.
3965 Specialization = VarTemplateSpecializationDecl::Create(
3966 Context, VarTemplate->getDeclContext(), TemplateKWLoc, TemplateNameLoc,
3967 VarTemplate, DI->getType(), DI, SC, Converted);
3968 Specialization->setTemplateArgsInfo(TemplateArgs);
3969
3970 if (!PrevDecl)
3971 VarTemplate->AddSpecialization(Specialization, InsertPos);
3972 }
3973
3974 // C++ [temp.expl.spec]p6:
3975 // If a template, a member template or the member of a class template is
3976 // explicitly specialized then that specialization shall be declared
3977 // before the first use of that specialization that would cause an implicit
3978 // instantiation to take place, in every translation unit in which such a
3979 // use occurs; no diagnostic is required.
3980 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
3981 bool Okay = false;
3982 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
3983 // Is there any previous explicit specialization declaration?
3984 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
3985 Okay = true;
3986 break;
3987 }
3988 }
3989
3990 if (!Okay) {
3991 SourceRange Range(TemplateNameLoc, RAngleLoc);
3992 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
3993 << Name << Range;
3994
3995 Diag(PrevDecl->getPointOfInstantiation(),
3996 diag::note_instantiation_required_here)
3997 << (PrevDecl->getTemplateSpecializationKind() !=
3998 TSK_ImplicitInstantiation);
3999 return true;
4000 }
4001 }
4002
4003 Specialization->setTemplateKeywordLoc(TemplateKWLoc);
4004 Specialization->setLexicalDeclContext(CurContext);
4005
4006 // Add the specialization into its lexical context, so that it can
4007 // be seen when iterating through the list of declarations in that
4008 // context. However, specializations are not found by name lookup.
4009 CurContext->addDecl(Specialization);
4010
4011 // Note that this is an explicit specialization.
4012 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
4013
4014 if (PrevDecl) {
4015 // Check that this isn't a redefinition of this specialization,
4016 // merging with previous declarations.
4017 LookupResult PrevSpec(*this, GetNameForDeclarator(D), LookupOrdinaryName,
4018 forRedeclarationInCurContext());
4019 PrevSpec.addDecl(PrevDecl);
4020 D.setRedeclaration(CheckVariableDeclaration(Specialization, PrevSpec));
4021 } else if (Specialization->isStaticDataMember() &&
4022 Specialization->isOutOfLine()) {
4023 Specialization->setAccess(VarTemplate->getAccess());
4024 }
4025
4026 return Specialization;
4027}
4028
4029namespace {
4030/// A partial specialization whose template arguments have matched
4031/// a given template-id.
4032struct PartialSpecMatchResult {
4033 VarTemplatePartialSpecializationDecl *Partial;
4034 TemplateArgumentList *Args;
4035};
4036} // end anonymous namespace
4037
4038DeclResult
4039Sema::CheckVarTemplateId(VarTemplateDecl *Template, SourceLocation TemplateLoc,
4040 SourceLocation TemplateNameLoc,
4041 const TemplateArgumentListInfo &TemplateArgs) {
4042 assert(Template && "A variable template id without template?")((Template && "A variable template id without template?"
) ? static_cast<void> (0) : __assert_fail ("Template && \"A variable template id without template?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4042, __PRETTY_FUNCTION__))
;
4043
4044 // Check that the template argument list is well-formed for this template.
4045 SmallVector<TemplateArgument, 4> Converted;
4046 if (CheckTemplateArgumentList(
4047 Template, TemplateNameLoc,
4048 const_cast<TemplateArgumentListInfo &>(TemplateArgs), false,
4049 Converted))
4050 return true;
4051
4052 // Find the variable template specialization declaration that
4053 // corresponds to these arguments.
4054 void *InsertPos = nullptr;
4055 if (VarTemplateSpecializationDecl *Spec = Template->findSpecialization(
4056 Converted, InsertPos)) {
4057 checkSpecializationVisibility(TemplateNameLoc, Spec);
4058 // If we already have a variable template specialization, return it.
4059 return Spec;
4060 }
4061
4062 // This is the first time we have referenced this variable template
4063 // specialization. Create the canonical declaration and add it to
4064 // the set of specializations, based on the closest partial specialization
4065 // that it represents. That is,
4066 VarDecl *InstantiationPattern = Template->getTemplatedDecl();
4067 TemplateArgumentList TemplateArgList(TemplateArgumentList::OnStack,
4068 Converted);
4069 TemplateArgumentList *InstantiationArgs = &TemplateArgList;
4070 bool AmbiguousPartialSpec = false;
4071 typedef PartialSpecMatchResult MatchResult;
4072 SmallVector<MatchResult, 4> Matched;
4073 SourceLocation PointOfInstantiation = TemplateNameLoc;
4074 TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation,
4075 /*ForTakingAddress=*/false);
4076
4077 // 1. Attempt to find the closest partial specialization that this
4078 // specializes, if any.
4079 // If any of the template arguments is dependent, then this is probably
4080 // a placeholder for an incomplete declarative context; which must be
4081 // complete by instantiation time. Thus, do not search through the partial
4082 // specializations yet.
4083 // TODO: Unify with InstantiateClassTemplateSpecialization()?
4084 // Perhaps better after unification of DeduceTemplateArguments() and
4085 // getMoreSpecializedPartialSpecialization().
4086 bool InstantiationDependent = false;
4087 if (!TemplateSpecializationType::anyDependentTemplateArguments(
4088 TemplateArgs, InstantiationDependent)) {
4089
4090 SmallVector<VarTemplatePartialSpecializationDecl *, 4> PartialSpecs;
4091 Template->getPartialSpecializations(PartialSpecs);
4092
4093 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
4094 VarTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
4095 TemplateDeductionInfo Info(FailedCandidates.getLocation());
4096
4097 if (TemplateDeductionResult Result =
4098 DeduceTemplateArguments(Partial, TemplateArgList, Info)) {
4099 // Store the failed-deduction information for use in diagnostics, later.
4100 // TODO: Actually use the failed-deduction info?
4101 FailedCandidates.addCandidate().set(
4102 DeclAccessPair::make(Template, AS_public), Partial,
4103 MakeDeductionFailureInfo(Context, Result, Info));
4104 (void)Result;
4105 } else {
4106 Matched.push_back(PartialSpecMatchResult());
4107 Matched.back().Partial = Partial;
4108 Matched.back().Args = Info.take();
4109 }
4110 }
4111
4112 if (Matched.size() >= 1) {
4113 SmallVector<MatchResult, 4>::iterator Best = Matched.begin();
4114 if (Matched.size() == 1) {
4115 // -- If exactly one matching specialization is found, the
4116 // instantiation is generated from that specialization.
4117 // We don't need to do anything for this.
4118 } else {
4119 // -- If more than one matching specialization is found, the
4120 // partial order rules (14.5.4.2) are used to determine
4121 // whether one of the specializations is more specialized
4122 // than the others. If none of the specializations is more
4123 // specialized than all of the other matching
4124 // specializations, then the use of the variable template is
4125 // ambiguous and the program is ill-formed.
4126 for (SmallVector<MatchResult, 4>::iterator P = Best + 1,
4127 PEnd = Matched.end();
4128 P != PEnd; ++P) {
4129 if (getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
4130 PointOfInstantiation) ==
4131 P->Partial)
4132 Best = P;
4133 }
4134
4135 // Determine if the best partial specialization is more specialized than
4136 // the others.
4137 for (SmallVector<MatchResult, 4>::iterator P = Matched.begin(),
4138 PEnd = Matched.end();
4139 P != PEnd; ++P) {
4140 if (P != Best && getMoreSpecializedPartialSpecialization(
4141 P->Partial, Best->Partial,
4142 PointOfInstantiation) != Best->Partial) {
4143 AmbiguousPartialSpec = true;
4144 break;
4145 }
4146 }
4147 }
4148
4149 // Instantiate using the best variable template partial specialization.
4150 InstantiationPattern = Best->Partial;
4151 InstantiationArgs = Best->Args;
4152 } else {
4153 // -- If no match is found, the instantiation is generated
4154 // from the primary template.
4155 // InstantiationPattern = Template->getTemplatedDecl();
4156 }
4157 }
4158
4159 // 2. Create the canonical declaration.
4160 // Note that we do not instantiate a definition until we see an odr-use
4161 // in DoMarkVarDeclReferenced().
4162 // FIXME: LateAttrs et al.?
4163 VarTemplateSpecializationDecl *Decl = BuildVarTemplateInstantiation(
4164 Template, InstantiationPattern, *InstantiationArgs, TemplateArgs,
4165 Converted, TemplateNameLoc, InsertPos /*, LateAttrs, StartingScope*/);
4166 if (!Decl)
4167 return true;
4168
4169 if (AmbiguousPartialSpec) {
4170 // Partial ordering did not produce a clear winner. Complain.
4171 Decl->setInvalidDecl();
4172 Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
4173 << Decl;
4174
4175 // Print the matching partial specializations.
4176 for (MatchResult P : Matched)
4177 Diag(P.Partial->getLocation(), diag::note_partial_spec_match)
4178 << getTemplateArgumentBindingsText(P.Partial->getTemplateParameters(),
4179 *P.Args);
4180 return true;
4181 }
4182
4183 if (VarTemplatePartialSpecializationDecl *D =
4184 dyn_cast<VarTemplatePartialSpecializationDecl>(InstantiationPattern))
4185 Decl->setInstantiationOf(D, InstantiationArgs);
4186
4187 checkSpecializationVisibility(TemplateNameLoc, Decl);
4188
4189 assert(Decl && "No variable template specialization?")((Decl && "No variable template specialization?") ? static_cast
<void> (0) : __assert_fail ("Decl && \"No variable template specialization?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4189, __PRETTY_FUNCTION__))
;
4190 return Decl;
4191}
4192
4193ExprResult
4194Sema::CheckVarTemplateId(const CXXScopeSpec &SS,
4195 const DeclarationNameInfo &NameInfo,
4196 VarTemplateDecl *Template, SourceLocation TemplateLoc,
4197 const TemplateArgumentListInfo *TemplateArgs) {
4198
4199 DeclResult Decl = CheckVarTemplateId(Template, TemplateLoc, NameInfo.getLoc(),
4200 *TemplateArgs);
4201 if (Decl.isInvalid())
4202 return ExprError();
4203
4204 VarDecl *Var = cast<VarDecl>(Decl.get());
4205 if (!Var->getTemplateSpecializationKind())
4206 Var->setTemplateSpecializationKind(TSK_ImplicitInstantiation,
4207 NameInfo.getLoc());
4208
4209 // Build an ordinary singleton decl ref.
4210 return BuildDeclarationNameExpr(SS, NameInfo, Var,
4211 /*FoundD=*/nullptr, TemplateArgs);
4212}
4213
4214void Sema::diagnoseMissingTemplateArguments(TemplateName Name,
4215 SourceLocation Loc) {
4216 Diag(Loc, diag::err_template_missing_args)
4217 << (int)getTemplateNameKindForDiagnostics(Name) << Name;
4218 if (TemplateDecl *TD = Name.getAsTemplateDecl()) {
4219 Diag(TD->getLocation(), diag::note_template_decl_here)
4220 << TD->getTemplateParameters()->getSourceRange();
4221 }
4222}
4223
4224ExprResult
4225Sema::CheckConceptTemplateId(const CXXScopeSpec &SS,
4226 SourceLocation TemplateKWLoc,
4227 SourceLocation ConceptNameLoc,
4228 NamedDecl *FoundDecl,
4229 ConceptDecl *NamedConcept,
4230 const TemplateArgumentListInfo *TemplateArgs) {
4231 assert(NamedConcept && "A concept template id without a template?")((NamedConcept && "A concept template id without a template?"
) ? static_cast<void> (0) : __assert_fail ("NamedConcept && \"A concept template id without a template?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4231, __PRETTY_FUNCTION__))
;
4232
4233 llvm::SmallVector<TemplateArgument, 4> Converted;
4234 if (CheckTemplateArgumentList(NamedConcept, ConceptNameLoc,
4235 const_cast<TemplateArgumentListInfo&>(*TemplateArgs),
4236 /*PartialTemplateArgs=*/false, Converted,
4237 /*UpdateArgsWithConversion=*/false))
4238 return ExprError();
4239
4240 Optional<bool> IsSatisfied;
4241 bool AreArgsDependent = false;
4242 for (TemplateArgument &Arg : Converted) {
4243 if (Arg.isDependent()) {
4244 AreArgsDependent = true;
4245 break;
4246 }
4247 }
4248 if (!AreArgsDependent) {
4249 InstantiatingTemplate Inst(*this, ConceptNameLoc,
4250 InstantiatingTemplate::ConstraintsCheck{}, NamedConcept, Converted,
4251 SourceRange(SS.isSet() ? SS.getBeginLoc() : ConceptNameLoc,
4252 TemplateArgs->getRAngleLoc()));
4253 MultiLevelTemplateArgumentList MLTAL;
4254 MLTAL.addOuterTemplateArguments(Converted);
4255 bool Satisfied;
4256 if (CalculateConstraintSatisfaction(NamedConcept, MLTAL,
4257 NamedConcept->getConstraintExpr(),
4258 Satisfied))
4259 return ExprError();
4260 IsSatisfied = Satisfied;
4261 }
4262 return ConceptSpecializationExpr::Create(Context,
4263 SS.isSet() ? SS.getWithLocInContext(Context) : NestedNameSpecifierLoc{},
4264 TemplateKWLoc, ConceptNameLoc, FoundDecl, NamedConcept,
4265 ASTTemplateArgumentListInfo::Create(Context, *TemplateArgs), Converted,
4266 IsSatisfied);
4267}
4268
4269ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
4270 SourceLocation TemplateKWLoc,
4271 LookupResult &R,
4272 bool RequiresADL,
4273 const TemplateArgumentListInfo *TemplateArgs) {
4274 // FIXME: Can we do any checking at this point? I guess we could check the
4275 // template arguments that we have against the template name, if the template
4276 // name refers to a single template. That's not a terribly common case,
4277 // though.
4278 // foo<int> could identify a single function unambiguously
4279 // This approach does NOT work, since f<int>(1);
4280 // gets resolved prior to resorting to overload resolution
4281 // i.e., template<class T> void f(double);
4282 // vs template<class T, class U> void f(U);
4283
4284 // These should be filtered out by our callers.
4285 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid")((!R.isAmbiguous() && "ambiguous lookup when building templateid"
) ? static_cast<void> (0) : __assert_fail ("!R.isAmbiguous() && \"ambiguous lookup when building templateid\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4285, __PRETTY_FUNCTION__))
;
4286
4287 // Non-function templates require a template argument list.
4288 if (auto *TD = R.getAsSingle<TemplateDecl>()) {
4289 if (!TemplateArgs && !isa<FunctionTemplateDecl>(TD)) {
4290 diagnoseMissingTemplateArguments(TemplateName(TD), R.getNameLoc());
4291 return ExprError();
4292 }
4293 }
4294
4295 auto AnyDependentArguments = [&]() -> bool {
4296 bool InstantiationDependent;
4297 return TemplateArgs &&
4298 TemplateSpecializationType::anyDependentTemplateArguments(
4299 *TemplateArgs, InstantiationDependent);
4300 };
4301
4302 // In C++1y, check variable template ids.
4303 if (R.getAsSingle<VarTemplateDecl>() && !AnyDependentArguments()) {
4304 return CheckVarTemplateId(SS, R.getLookupNameInfo(),
4305 R.getAsSingle<VarTemplateDecl>(),
4306 TemplateKWLoc, TemplateArgs);
4307 }
4308
4309 if (R.getAsSingle<ConceptDecl>()) {
4310 return CheckConceptTemplateId(SS, TemplateKWLoc,
4311 R.getLookupNameInfo().getBeginLoc(),
4312 R.getFoundDecl(),
4313 R.getAsSingle<ConceptDecl>(), TemplateArgs);
4314 }
4315
4316 // We don't want lookup warnings at this point.
4317 R.suppressDiagnostics();
4318
4319 UnresolvedLookupExpr *ULE
4320 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
4321 SS.getWithLocInContext(Context),
4322 TemplateKWLoc,
4323 R.getLookupNameInfo(),
4324 RequiresADL, TemplateArgs,
4325 R.begin(), R.end());
4326
4327 return ULE;
4328}
4329
4330// We actually only call this from template instantiation.
4331ExprResult
4332Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
4333 SourceLocation TemplateKWLoc,
4334 const DeclarationNameInfo &NameInfo,
4335 const TemplateArgumentListInfo *TemplateArgs) {
4336
4337 assert(TemplateArgs || TemplateKWLoc.isValid())((TemplateArgs || TemplateKWLoc.isValid()) ? static_cast<void
> (0) : __assert_fail ("TemplateArgs || TemplateKWLoc.isValid()"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4337, __PRETTY_FUNCTION__))
;
4338 DeclContext *DC;
4339 if (!(DC = computeDeclContext(SS, false)) ||
4340 DC->isDependentContext() ||
4341 RequireCompleteDeclContext(SS, DC))
4342 return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs);
4343
4344 bool MemberOfUnknownSpecialization;
4345 LookupResult R(*this, NameInfo, LookupOrdinaryName);
4346 if (LookupTemplateName(R, (Scope *)nullptr, SS, QualType(),
4347 /*Entering*/false, MemberOfUnknownSpecialization,
4348 TemplateKWLoc))
4349 return ExprError();
4350
4351 if (R.isAmbiguous())
4352 return ExprError();
4353
4354 if (R.empty()) {
4355 Diag(NameInfo.getLoc(), diag::err_no_member)
4356 << NameInfo.getName() << DC << SS.getRange();
4357 return ExprError();
4358 }
4359
4360 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
4361 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template)
4362 << SS.getScopeRep()
4363 << NameInfo.getName().getAsString() << SS.getRange();
4364 Diag(Temp->getLocation(), diag::note_referenced_class_template);
4365 return ExprError();
4366 }
4367
4368 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, /*ADL*/ false, TemplateArgs);
4369}
4370
4371/// Form a dependent template name.
4372///
4373/// This action forms a dependent template name given the template
4374/// name and its (presumably dependent) scope specifier. For
4375/// example, given "MetaFun::template apply", the scope specifier \p
4376/// SS will be "MetaFun::", \p TemplateKWLoc contains the location
4377/// of the "template" keyword, and "apply" is the \p Name.
4378TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
4379 CXXScopeSpec &SS,
4380 SourceLocation TemplateKWLoc,
4381 const UnqualifiedId &Name,
4382 ParsedType ObjectType,
4383 bool EnteringContext,
4384 TemplateTy &Result,
4385 bool AllowInjectedClassName) {
4386 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent())
4387 Diag(TemplateKWLoc,
4388 getLangOpts().CPlusPlus11 ?
4389 diag::warn_cxx98_compat_template_outside_of_template :
4390 diag::ext_template_outside_of_template)
4391 << FixItHint::CreateRemoval(TemplateKWLoc);
4392
4393 DeclContext *LookupCtx = nullptr;
4394 if (SS.isSet())
4395 LookupCtx = computeDeclContext(SS, EnteringContext);
4396 if (!LookupCtx && ObjectType)
4397 LookupCtx = computeDeclContext(ObjectType.get());
4398 if (LookupCtx) {
4399 // C++0x [temp.names]p5:
4400 // If a name prefixed by the keyword template is not the name of
4401 // a template, the program is ill-formed. [Note: the keyword
4402 // template may not be applied to non-template members of class
4403 // templates. -end note ] [ Note: as is the case with the
4404 // typename prefix, the template prefix is allowed in cases
4405 // where it is not strictly necessary; i.e., when the
4406 // nested-name-specifier or the expression on the left of the ->
4407 // or . is not dependent on a template-parameter, or the use
4408 // does not appear in the scope of a template. -end note]
4409 //
4410 // Note: C++03 was more strict here, because it banned the use of
4411 // the "template" keyword prior to a template-name that was not a
4412 // dependent name. C++ DR468 relaxed this requirement (the
4413 // "template" keyword is now permitted). We follow the C++0x
4414 // rules, even in C++03 mode with a warning, retroactively applying the DR.
4415 bool MemberOfUnknownSpecialization;
4416 TemplateNameKind TNK = isTemplateName(S, SS, TemplateKWLoc.isValid(), Name,
4417 ObjectType, EnteringContext, Result,
4418 MemberOfUnknownSpecialization);
4419 if (TNK == TNK_Non_template && MemberOfUnknownSpecialization) {
4420 // This is a dependent template. Handle it below.
4421 } else if (TNK == TNK_Non_template) {
4422 // Do the lookup again to determine if this is a "nothing found" case or
4423 // a "not a template" case. FIXME: Refactor isTemplateName so we don't
4424 // need to do this.
4425 DeclarationNameInfo DNI = GetNameFromUnqualifiedId(Name);
4426 LookupResult R(*this, DNI.getName(), Name.getBeginLoc(),
4427 LookupOrdinaryName);
4428 bool MOUS;
4429 if (!LookupTemplateName(R, S, SS, ObjectType.get(), EnteringContext,
4430 MOUS, TemplateKWLoc) && !R.isAmbiguous())
4431 Diag(Name.getBeginLoc(), diag::err_no_member)
4432 << DNI.getName() << LookupCtx << SS.getRange();
4433 return TNK_Non_template;
4434 } else {
4435 // We found something; return it.
4436 auto *LookupRD = dyn_cast<CXXRecordDecl>(LookupCtx);
4437 if (!AllowInjectedClassName && SS.isSet() && LookupRD &&
4438 Name.getKind() == UnqualifiedIdKind::IK_Identifier &&
4439 Name.Identifier && LookupRD->getIdentifier() == Name.Identifier) {
4440 // C++14 [class.qual]p2:
4441 // In a lookup in which function names are not ignored and the
4442 // nested-name-specifier nominates a class C, if the name specified
4443 // [...] is the injected-class-name of C, [...] the name is instead
4444 // considered to name the constructor
4445 //
4446 // We don't get here if naming the constructor would be valid, so we
4447 // just reject immediately and recover by treating the
4448 // injected-class-name as naming the template.
4449 Diag(Name.getBeginLoc(),
4450 diag::ext_out_of_line_qualified_id_type_names_constructor)
4451 << Name.Identifier
4452 << 0 /*injected-class-name used as template name*/
4453 << 1 /*'template' keyword was used*/;
4454 }
4455 return TNK;
4456 }
4457 }
4458
4459 NestedNameSpecifier *Qualifier = SS.getScopeRep();
4460
4461 switch (Name.getKind()) {
4462 case UnqualifiedIdKind::IK_Identifier:
4463 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
4464 Name.Identifier));
4465 return TNK_Dependent_template_name;
4466
4467 case UnqualifiedIdKind::IK_OperatorFunctionId:
4468 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
4469 Name.OperatorFunctionId.Operator));
4470 return TNK_Function_template;
4471
4472 case UnqualifiedIdKind::IK_LiteralOperatorId:
4473 llvm_unreachable("literal operator id cannot have a dependent scope")::llvm::llvm_unreachable_internal("literal operator id cannot have a dependent scope"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4473)
;
4474
4475 default:
4476 break;
4477 }
4478
4479 Diag(Name.getBeginLoc(), diag::err_template_kw_refers_to_non_template)
4480 << GetNameFromUnqualifiedId(Name).getName() << Name.getSourceRange()
4481 << TemplateKWLoc;
4482 return TNK_Non_template;
4483}
4484
4485bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
4486 TemplateArgumentLoc &AL,
4487 SmallVectorImpl<TemplateArgument> &Converted) {
4488 const TemplateArgument &Arg = AL.getArgument();
4489 QualType ArgType;
4490 TypeSourceInfo *TSI = nullptr;
4491
4492 // Check template type parameter.
4493 switch(Arg.getKind()) {
4494 case TemplateArgument::Type:
4495 // C++ [temp.arg.type]p1:
4496 // A template-argument for a template-parameter which is a
4497 // type shall be a type-id.
4498 ArgType = Arg.getAsType();
4499 TSI = AL.getTypeSourceInfo();
4500 break;
4501 case TemplateArgument::Template:
4502 case TemplateArgument::TemplateExpansion: {
4503 // We have a template type parameter but the template argument
4504 // is a template without any arguments.
4505 SourceRange SR = AL.getSourceRange();
4506 TemplateName Name = Arg.getAsTemplateOrTemplatePattern();
4507 diagnoseMissingTemplateArguments(Name, SR.getEnd());
4508 return true;
4509 }
4510 case TemplateArgument::Expression: {
4511 // We have a template type parameter but the template argument is an
4512 // expression; see if maybe it is missing the "typename" keyword.
4513 CXXScopeSpec SS;
4514 DeclarationNameInfo NameInfo;
4515
4516 if (DeclRefExpr *ArgExpr = dyn_cast<DeclRefExpr>(Arg.getAsExpr())) {
4517 SS.Adopt(ArgExpr->getQualifierLoc());
4518 NameInfo = ArgExpr->getNameInfo();
4519 } else if (DependentScopeDeclRefExpr *ArgExpr =
4520 dyn_cast<DependentScopeDeclRefExpr>(Arg.getAsExpr())) {
4521 SS.Adopt(ArgExpr->getQualifierLoc());
4522 NameInfo = ArgExpr->getNameInfo();
4523 } else if (CXXDependentScopeMemberExpr *ArgExpr =
4524 dyn_cast<CXXDependentScopeMemberExpr>(Arg.getAsExpr())) {
4525 if (ArgExpr->isImplicitAccess()) {
4526 SS.Adopt(ArgExpr->getQualifierLoc());
4527 NameInfo = ArgExpr->getMemberNameInfo();
4528 }
4529 }
4530
4531 if (auto *II = NameInfo.getName().getAsIdentifierInfo()) {
4532 LookupResult Result(*this, NameInfo, LookupOrdinaryName);
4533 LookupParsedName(Result, CurScope, &SS);
4534
4535 if (Result.getAsSingle<TypeDecl>() ||
4536 Result.getResultKind() ==
4537 LookupResult::NotFoundInCurrentInstantiation) {
4538 // Suggest that the user add 'typename' before the NNS.
4539 SourceLocation Loc = AL.getSourceRange().getBegin();
4540 Diag(Loc, getLangOpts().MSVCCompat
4541 ? diag::ext_ms_template_type_arg_missing_typename
4542 : diag::err_template_arg_must_be_type_suggest)
4543 << FixItHint::CreateInsertion(Loc, "typename ");
4544 Diag(Param->getLocation(), diag::note_template_param_here);
4545
4546 // Recover by synthesizing a type using the location information that we
4547 // already have.
4548 ArgType =
4549 Context.getDependentNameType(ETK_Typename, SS.getScopeRep(), II);
4550 TypeLocBuilder TLB;
4551 DependentNameTypeLoc TL = TLB.push<DependentNameTypeLoc>(ArgType);
4552 TL.setElaboratedKeywordLoc(SourceLocation(/*synthesized*/));
4553 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4554 TL.setNameLoc(NameInfo.getLoc());
4555 TSI = TLB.getTypeSourceInfo(Context, ArgType);
4556
4557 // Overwrite our input TemplateArgumentLoc so that we can recover
4558 // properly.
4559 AL = TemplateArgumentLoc(TemplateArgument(ArgType),
4560 TemplateArgumentLocInfo(TSI));
4561
4562 break;
4563 }
4564 }
4565 // fallthrough
4566 LLVM_FALLTHROUGH[[gnu::fallthrough]];
4567 }
4568 default: {
4569 // We have a template type parameter but the template argument
4570 // is not a type.
4571 SourceRange SR = AL.getSourceRange();
4572 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
4573 Diag(Param->getLocation(), diag::note_template_param_here);
4574
4575 return true;
4576 }
4577 }
4578
4579 if (CheckTemplateArgument(Param, TSI))
4580 return true;
4581
4582 // Add the converted template type argument.
4583 ArgType = Context.getCanonicalType(ArgType);
4584
4585 // Objective-C ARC:
4586 // If an explicitly-specified template argument type is a lifetime type
4587 // with no lifetime qualifier, the __strong lifetime qualifier is inferred.
4588 if (getLangOpts().ObjCAutoRefCount &&
4589 ArgType->isObjCLifetimeType() &&
4590 !ArgType.getObjCLifetime()) {
4591 Qualifiers Qs;
4592 Qs.setObjCLifetime(Qualifiers::OCL_Strong);
4593 ArgType = Context.getQualifiedType(ArgType, Qs);
4594 }
4595
4596 Converted.push_back(TemplateArgument(ArgType));
4597 return false;
4598}
4599
4600/// Substitute template arguments into the default template argument for
4601/// the given template type parameter.
4602///
4603/// \param SemaRef the semantic analysis object for which we are performing
4604/// the substitution.
4605///
4606/// \param Template the template that we are synthesizing template arguments
4607/// for.
4608///
4609/// \param TemplateLoc the location of the template name that started the
4610/// template-id we are checking.
4611///
4612/// \param RAngleLoc the location of the right angle bracket ('>') that
4613/// terminates the template-id.
4614///
4615/// \param Param the template template parameter whose default we are
4616/// substituting into.
4617///
4618/// \param Converted the list of template arguments provided for template
4619/// parameters that precede \p Param in the template parameter list.
4620/// \returns the substituted template argument, or NULL if an error occurred.
4621static TypeSourceInfo *
4622SubstDefaultTemplateArgument(Sema &SemaRef,
4623 TemplateDecl *Template,
4624 SourceLocation TemplateLoc,
4625 SourceLocation RAngleLoc,
4626 TemplateTypeParmDecl *Param,
4627 SmallVectorImpl<TemplateArgument> &Converted) {
4628 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
4629
4630 // If the argument type is dependent, instantiate it now based
4631 // on the previously-computed template arguments.
4632 if (ArgType->getType()->isInstantiationDependentType()) {
4633 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
4634 Param, Template, Converted,
4635 SourceRange(TemplateLoc, RAngleLoc));
4636 if (Inst.isInvalid())
4637 return nullptr;
4638
4639 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Converted);
4640
4641 // Only substitute for the innermost template argument list.
4642 MultiLevelTemplateArgumentList TemplateArgLists;
4643 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
4644 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
4645 TemplateArgLists.addOuterTemplateArguments(None);
4646
4647 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
4648 ArgType =
4649 SemaRef.SubstType(ArgType, TemplateArgLists,
4650 Param->getDefaultArgumentLoc(), Param->getDeclName());
4651 }
4652
4653 return ArgType;
4654}
4655
4656/// Substitute template arguments into the default template argument for
4657/// the given non-type template parameter.
4658///
4659/// \param SemaRef the semantic analysis object for which we are performing
4660/// the substitution.
4661///
4662/// \param Template the template that we are synthesizing template arguments
4663/// for.
4664///
4665/// \param TemplateLoc the location of the template name that started the
4666/// template-id we are checking.
4667///
4668/// \param RAngleLoc the location of the right angle bracket ('>') that
4669/// terminates the template-id.
4670///
4671/// \param Param the non-type template parameter whose default we are
4672/// substituting into.
4673///
4674/// \param Converted the list of template arguments provided for template
4675/// parameters that precede \p Param in the template parameter list.
4676///
4677/// \returns the substituted template argument, or NULL if an error occurred.
4678static ExprResult
4679SubstDefaultTemplateArgument(Sema &SemaRef,
4680 TemplateDecl *Template,
4681 SourceLocation TemplateLoc,
4682 SourceLocation RAngleLoc,
4683 NonTypeTemplateParmDecl *Param,
4684 SmallVectorImpl<TemplateArgument> &Converted) {
4685 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
4686 Param, Template, Converted,
4687 SourceRange(TemplateLoc, RAngleLoc));
4688 if (Inst.isInvalid())
4689 return ExprError();
4690
4691 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Converted);
4692
4693 // Only substitute for the innermost template argument list.
4694 MultiLevelTemplateArgumentList TemplateArgLists;
4695 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
4696 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
4697 TemplateArgLists.addOuterTemplateArguments(None);
4698
4699 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
4700 EnterExpressionEvaluationContext ConstantEvaluated(
4701 SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
4702 return SemaRef.SubstExpr(Param->getDefaultArgument(), TemplateArgLists);
4703}
4704
4705/// Substitute template arguments into the default template argument for
4706/// the given template template parameter.
4707///
4708/// \param SemaRef the semantic analysis object for which we are performing
4709/// the substitution.
4710///
4711/// \param Template the template that we are synthesizing template arguments
4712/// for.
4713///
4714/// \param TemplateLoc the location of the template name that started the
4715/// template-id we are checking.
4716///
4717/// \param RAngleLoc the location of the right angle bracket ('>') that
4718/// terminates the template-id.
4719///
4720/// \param Param the template template parameter whose default we are
4721/// substituting into.
4722///
4723/// \param Converted the list of template arguments provided for template
4724/// parameters that precede \p Param in the template parameter list.
4725///
4726/// \param QualifierLoc Will be set to the nested-name-specifier (with
4727/// source-location information) that precedes the template name.
4728///
4729/// \returns the substituted template argument, or NULL if an error occurred.
4730static TemplateName
4731SubstDefaultTemplateArgument(Sema &SemaRef,
4732 TemplateDecl *Template,
4733 SourceLocation TemplateLoc,
4734 SourceLocation RAngleLoc,
4735 TemplateTemplateParmDecl *Param,
4736 SmallVectorImpl<TemplateArgument> &Converted,
4737 NestedNameSpecifierLoc &QualifierLoc) {
4738 Sema::InstantiatingTemplate Inst(
4739 SemaRef, TemplateLoc, TemplateParameter(Param), Template, Converted,
4740 SourceRange(TemplateLoc, RAngleLoc));
4741 if (Inst.isInvalid())
4742 return TemplateName();
4743
4744 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Converted);
4745
4746 // Only substitute for the innermost template argument list.
4747 MultiLevelTemplateArgumentList TemplateArgLists;
4748 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
4749 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
4750 TemplateArgLists.addOuterTemplateArguments(None);
4751
4752 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
4753 // Substitute into the nested-name-specifier first,
4754 QualifierLoc = Param->getDefaultArgument().getTemplateQualifierLoc();
4755 if (QualifierLoc) {
4756 QualifierLoc =
4757 SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgLists);
4758 if (!QualifierLoc)
4759 return TemplateName();
4760 }
4761
4762 return SemaRef.SubstTemplateName(
4763 QualifierLoc,
4764 Param->getDefaultArgument().getArgument().getAsTemplate(),
4765 Param->getDefaultArgument().getTemplateNameLoc(),
4766 TemplateArgLists);
4767}
4768
4769/// If the given template parameter has a default template
4770/// argument, substitute into that default template argument and
4771/// return the corresponding template argument.
4772TemplateArgumentLoc
4773Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
4774 SourceLocation TemplateLoc,
4775 SourceLocation RAngleLoc,
4776 Decl *Param,
4777 SmallVectorImpl<TemplateArgument>
4778 &Converted,
4779 bool &HasDefaultArg) {
4780 HasDefaultArg = false;
4781
4782 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
4783 if (!hasVisibleDefaultArgument(TypeParm))
4784 return TemplateArgumentLoc();
4785
4786 HasDefaultArg = true;
4787 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
4788 TemplateLoc,
4789 RAngleLoc,
4790 TypeParm,
4791 Converted);
4792 if (DI)
4793 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
4794
4795 return TemplateArgumentLoc();
4796 }
4797
4798 if (NonTypeTemplateParmDecl *NonTypeParm
4799 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
4800 if (!hasVisibleDefaultArgument(NonTypeParm))
4801 return TemplateArgumentLoc();
4802
4803 HasDefaultArg = true;
4804 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
4805 TemplateLoc,
4806 RAngleLoc,
4807 NonTypeParm,
4808 Converted);
4809 if (Arg.isInvalid())
4810 return TemplateArgumentLoc();
4811
4812 Expr *ArgE = Arg.getAs<Expr>();
4813 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
4814 }
4815
4816 TemplateTemplateParmDecl *TempTempParm
4817 = cast<TemplateTemplateParmDecl>(Param);
4818 if (!hasVisibleDefaultArgument(TempTempParm))
4819 return TemplateArgumentLoc();
4820
4821 HasDefaultArg = true;
4822 NestedNameSpecifierLoc QualifierLoc;
4823 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
4824 TemplateLoc,
4825 RAngleLoc,
4826 TempTempParm,
4827 Converted,
4828 QualifierLoc);
4829 if (TName.isNull())
4830 return TemplateArgumentLoc();
4831
4832 return TemplateArgumentLoc(TemplateArgument(TName),
4833 TempTempParm->getDefaultArgument().getTemplateQualifierLoc(),
4834 TempTempParm->getDefaultArgument().getTemplateNameLoc());
4835}
4836
4837/// Convert a template-argument that we parsed as a type into a template, if
4838/// possible. C++ permits injected-class-names to perform dual service as
4839/// template template arguments and as template type arguments.
4840static TemplateArgumentLoc convertTypeTemplateArgumentToTemplate(TypeLoc TLoc) {
4841 // Extract and step over any surrounding nested-name-specifier.
4842 NestedNameSpecifierLoc QualLoc;
4843 if (auto ETLoc = TLoc.getAs<ElaboratedTypeLoc>()) {
4844 if (ETLoc.getTypePtr()->getKeyword() != ETK_None)
4845 return TemplateArgumentLoc();
4846
4847 QualLoc = ETLoc.getQualifierLoc();
4848 TLoc = ETLoc.getNamedTypeLoc();
4849 }
4850
4851 // If this type was written as an injected-class-name, it can be used as a
4852 // template template argument.
4853 if (auto InjLoc = TLoc.getAs<InjectedClassNameTypeLoc>())
4854 return TemplateArgumentLoc(InjLoc.getTypePtr()->getTemplateName(),
4855 QualLoc, InjLoc.getNameLoc());
4856
4857 // If this type was written as an injected-class-name, it may have been
4858 // converted to a RecordType during instantiation. If the RecordType is
4859 // *not* wrapped in a TemplateSpecializationType and denotes a class
4860 // template specialization, it must have come from an injected-class-name.
4861 if (auto RecLoc = TLoc.getAs<RecordTypeLoc>())
4862 if (auto *CTSD =
4863 dyn_cast<ClassTemplateSpecializationDecl>(RecLoc.getDecl()))
4864 return TemplateArgumentLoc(TemplateName(CTSD->getSpecializedTemplate()),
4865 QualLoc, RecLoc.getNameLoc());
4866
4867 return TemplateArgumentLoc();
4868}
4869
4870/// Check that the given template argument corresponds to the given
4871/// template parameter.
4872///
4873/// \param Param The template parameter against which the argument will be
4874/// checked.
4875///
4876/// \param Arg The template argument, which may be updated due to conversions.
4877///
4878/// \param Template The template in which the template argument resides.
4879///
4880/// \param TemplateLoc The location of the template name for the template
4881/// whose argument list we're matching.
4882///
4883/// \param RAngleLoc The location of the right angle bracket ('>') that closes
4884/// the template argument list.
4885///
4886/// \param ArgumentPackIndex The index into the argument pack where this
4887/// argument will be placed. Only valid if the parameter is a parameter pack.
4888///
4889/// \param Converted The checked, converted argument will be added to the
4890/// end of this small vector.
4891///
4892/// \param CTAK Describes how we arrived at this particular template argument:
4893/// explicitly written, deduced, etc.
4894///
4895/// \returns true on error, false otherwise.
4896bool Sema::CheckTemplateArgument(NamedDecl *Param,
4897 TemplateArgumentLoc &Arg,
4898 NamedDecl *Template,
4899 SourceLocation TemplateLoc,
4900 SourceLocation RAngleLoc,
4901 unsigned ArgumentPackIndex,
4902 SmallVectorImpl<TemplateArgument> &Converted,
4903 CheckTemplateArgumentKind CTAK) {
4904 // Check template type parameters.
4905 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
4906 return CheckTemplateTypeArgument(TTP, Arg, Converted);
4907
4908 // Check non-type template parameters.
4909 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
4910 // Do substitution on the type of the non-type template parameter
4911 // with the template arguments we've seen thus far. But if the
4912 // template has a dependent context then we cannot substitute yet.
4913 QualType NTTPType = NTTP->getType();
4914 if (NTTP->isParameterPack() && NTTP->isExpandedParameterPack())
4915 NTTPType = NTTP->getExpansionType(ArgumentPackIndex);
4916
4917 if (NTTPType->isInstantiationDependentType() &&
4918 !isa<TemplateTemplateParmDecl>(Template) &&
4919 !Template->getDeclContext()->isDependentContext()) {
4920 // Do substitution on the type of the non-type template parameter.
4921 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
4922 NTTP, Converted,
4923 SourceRange(TemplateLoc, RAngleLoc));
4924 if (Inst.isInvalid())
4925 return true;
4926
4927 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
4928 Converted);
4929
4930 // If the parameter is a pack expansion, expand this slice of the pack.
4931 if (auto *PET = NTTPType->getAs<PackExpansionType>()) {
4932 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this,
4933 ArgumentPackIndex);
4934 NTTPType = SubstType(PET->getPattern(),
4935 MultiLevelTemplateArgumentList(TemplateArgs),
4936 NTTP->getLocation(),
4937 NTTP->getDeclName());
4938 } else {
4939 NTTPType = SubstType(NTTPType,
4940 MultiLevelTemplateArgumentList(TemplateArgs),
4941 NTTP->getLocation(),
4942 NTTP->getDeclName());
4943 }
4944
4945 // If that worked, check the non-type template parameter type
4946 // for validity.
4947 if (!NTTPType.isNull())
4948 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
4949 NTTP->getLocation());
4950 if (NTTPType.isNull())
4951 return true;
4952 }
4953
4954 switch (Arg.getArgument().getKind()) {
4955 case TemplateArgument::Null:
4956 llvm_unreachable("Should never see a NULL template argument here")::llvm::llvm_unreachable_internal("Should never see a NULL template argument here"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 4956)
;
4957
4958 case TemplateArgument::Expression: {
4959 TemplateArgument Result;
4960 unsigned CurSFINAEErrors = NumSFINAEErrors;
4961 ExprResult Res =
4962 CheckTemplateArgument(NTTP, NTTPType, Arg.getArgument().getAsExpr(),
4963 Result, CTAK);
4964 if (Res.isInvalid())
4965 return true;
4966 // If the current template argument causes an error, give up now.
4967 if (CurSFINAEErrors < NumSFINAEErrors)
4968 return true;
4969
4970 // If the resulting expression is new, then use it in place of the
4971 // old expression in the template argument.
4972 if (Res.get() != Arg.getArgument().getAsExpr()) {
4973 TemplateArgument TA(Res.get());
4974 Arg = TemplateArgumentLoc(TA, Res.get());
4975 }
4976
4977 Converted.push_back(Result);
4978 break;
4979 }
4980
4981 case TemplateArgument::Declaration:
4982 case TemplateArgument::Integral:
4983 case TemplateArgument::NullPtr:
4984 // We've already checked this template argument, so just copy
4985 // it to the list of converted arguments.
4986 Converted.push_back(Arg.getArgument());
4987 break;
4988
4989 case TemplateArgument::Template:
4990 case TemplateArgument::TemplateExpansion:
4991 // We were given a template template argument. It may not be ill-formed;
4992 // see below.
4993 if (DependentTemplateName *DTN
4994 = Arg.getArgument().getAsTemplateOrTemplatePattern()
4995 .getAsDependentTemplateName()) {
4996 // We have a template argument such as \c T::template X, which we
4997 // parsed as a template template argument. However, since we now
4998 // know that we need a non-type template argument, convert this
4999 // template name into an expression.
5000
5001 DeclarationNameInfo NameInfo(DTN->getIdentifier(),
5002 Arg.getTemplateNameLoc());
5003
5004 CXXScopeSpec SS;
5005 SS.Adopt(Arg.getTemplateQualifierLoc());
5006 // FIXME: the template-template arg was a DependentTemplateName,
5007 // so it was provided with a template keyword. However, its source
5008 // location is not stored in the template argument structure.
5009 SourceLocation TemplateKWLoc;
5010 ExprResult E = DependentScopeDeclRefExpr::Create(
5011 Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
5012 nullptr);
5013
5014 // If we parsed the template argument as a pack expansion, create a
5015 // pack expansion expression.
5016 if (Arg.getArgument().getKind() == TemplateArgument::TemplateExpansion){
5017 E = ActOnPackExpansion(E.get(), Arg.getTemplateEllipsisLoc());
5018 if (E.isInvalid())
5019 return true;
5020 }
5021
5022 TemplateArgument Result;
5023 E = CheckTemplateArgument(NTTP, NTTPType, E.get(), Result);
5024 if (E.isInvalid())
5025 return true;
5026
5027 Converted.push_back(Result);
5028 break;
5029 }
5030
5031 // We have a template argument that actually does refer to a class
5032 // template, alias template, or template template parameter, and
5033 // therefore cannot be a non-type template argument.
5034 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
5035 << Arg.getSourceRange();
5036
5037 Diag(Param->getLocation(), diag::note_template_param_here);
5038 return true;
5039
5040 case TemplateArgument::Type: {
5041 // We have a non-type template parameter but the template
5042 // argument is a type.
5043
5044 // C++ [temp.arg]p2:
5045 // In a template-argument, an ambiguity between a type-id and
5046 // an expression is resolved to a type-id, regardless of the
5047 // form of the corresponding template-parameter.
5048 //
5049 // We warn specifically about this case, since it can be rather
5050 // confusing for users.
5051 QualType T = Arg.getArgument().getAsType();
5052 SourceRange SR = Arg.getSourceRange();
5053 if (T->isFunctionType())
5054 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
5055 else
5056 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
5057 Diag(Param->getLocation(), diag::note_template_param_here);
5058 return true;
5059 }
5060
5061 case TemplateArgument::Pack:
5062 llvm_unreachable("Caller must expand template argument packs")::llvm::llvm_unreachable_internal("Caller must expand template argument packs"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5062)
;
5063 }
5064
5065 return false;
5066 }
5067
5068
5069 // Check template template parameters.
5070 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
5071
5072 TemplateParameterList *Params = TempParm->getTemplateParameters();
5073 if (TempParm->isExpandedParameterPack())
5074 Params = TempParm->getExpansionTemplateParameters(ArgumentPackIndex);
5075
5076 // Substitute into the template parameter list of the template
5077 // template parameter, since previously-supplied template arguments
5078 // may appear within the template template parameter.
5079 //
5080 // FIXME: Skip this if the parameters aren't instantiation-dependent.
5081 {
5082 // Set up a template instantiation context.
5083 LocalInstantiationScope Scope(*this);
5084 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
5085 TempParm, Converted,
5086 SourceRange(TemplateLoc, RAngleLoc));
5087 if (Inst.isInvalid())
5088 return true;
5089
5090 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Converted);
5091 Params = SubstTemplateParams(Params, CurContext,
5092 MultiLevelTemplateArgumentList(TemplateArgs));
5093 if (!Params)
5094 return true;
5095 }
5096
5097 // C++1z [temp.local]p1: (DR1004)
5098 // When [the injected-class-name] is used [...] as a template-argument for
5099 // a template template-parameter [...] it refers to the class template
5100 // itself.
5101 if (Arg.getArgument().getKind() == TemplateArgument::Type) {
5102 TemplateArgumentLoc ConvertedArg = convertTypeTemplateArgumentToTemplate(
5103 Arg.getTypeSourceInfo()->getTypeLoc());
5104 if (!ConvertedArg.getArgument().isNull())
5105 Arg = ConvertedArg;
5106 }
5107
5108 switch (Arg.getArgument().getKind()) {
5109 case TemplateArgument::Null:
5110 llvm_unreachable("Should never see a NULL template argument here")::llvm::llvm_unreachable_internal("Should never see a NULL template argument here"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5110)
;
5111
5112 case TemplateArgument::Template:
5113 case TemplateArgument::TemplateExpansion:
5114 if (CheckTemplateTemplateArgument(Params, Arg))
5115 return true;
5116
5117 Converted.push_back(Arg.getArgument());
5118 break;
5119
5120 case TemplateArgument::Expression:
5121 case TemplateArgument::Type:
5122 // We have a template template parameter but the template
5123 // argument does not refer to a template.
5124 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template)
5125 << getLangOpts().CPlusPlus11;
5126 return true;
5127
5128 case TemplateArgument::Declaration:
5129 llvm_unreachable("Declaration argument with template template parameter")::llvm::llvm_unreachable_internal("Declaration argument with template template parameter"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5129)
;
5130 case TemplateArgument::Integral:
5131 llvm_unreachable("Integral argument with template template parameter")::llvm::llvm_unreachable_internal("Integral argument with template template parameter"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5131)
;
5132 case TemplateArgument::NullPtr:
5133 llvm_unreachable("Null pointer argument with template template parameter")::llvm::llvm_unreachable_internal("Null pointer argument with template template parameter"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5133)
;
5134
5135 case TemplateArgument::Pack:
5136 llvm_unreachable("Caller must expand template argument packs")::llvm::llvm_unreachable_internal("Caller must expand template argument packs"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5136)
;
5137 }
5138
5139 return false;
5140}
5141
5142/// Check whether the template parameter is a pack expansion, and if so,
5143/// determine the number of parameters produced by that expansion. For instance:
5144///
5145/// \code
5146/// template<typename ...Ts> struct A {
5147/// template<Ts ...NTs, template<Ts> class ...TTs, typename ...Us> struct B;
5148/// };
5149/// \endcode
5150///
5151/// In \c A<int,int>::B, \c NTs and \c TTs have expanded pack size 2, and \c Us
5152/// is not a pack expansion, so returns an empty Optional.
5153static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
5154 if (NonTypeTemplateParmDecl *NTTP
5155 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
5156 if (NTTP->isExpandedParameterPack())
5157 return NTTP->getNumExpansionTypes();
5158 }
5159
5160 if (TemplateTemplateParmDecl *TTP
5161 = dyn_cast<TemplateTemplateParmDecl>(Param)) {
5162 if (TTP->isExpandedParameterPack())
5163 return TTP->getNumExpansionTemplateParameters();
5164 }
5165
5166 return None;
5167}
5168
5169/// Diagnose a missing template argument.
5170template<typename TemplateParmDecl>
5171static bool diagnoseMissingArgument(Sema &S, SourceLocation Loc,
5172 TemplateDecl *TD,
5173 const TemplateParmDecl *D,
5174 TemplateArgumentListInfo &Args) {
5175 // Dig out the most recent declaration of the template parameter; there may be
5176 // declarations of the template that are more recent than TD.
5177 D = cast<TemplateParmDecl>(cast<TemplateDecl>(TD->getMostRecentDecl())
5178 ->getTemplateParameters()
5179 ->getParam(D->getIndex()));
5180
5181 // If there's a default argument that's not visible, diagnose that we're
5182 // missing a module import.
5183 llvm::SmallVector<Module*, 8> Modules;
5184 if (D->hasDefaultArgument() && !S.hasVisibleDefaultArgument(D, &Modules)) {
5185 S.diagnoseMissingImport(Loc, cast<NamedDecl>(TD),
5186 D->getDefaultArgumentLoc(), Modules,
5187 Sema::MissingImportKind::DefaultArgument,
5188 /*Recover*/true);
5189 return true;
5190 }
5191
5192 // FIXME: If there's a more recent default argument that *is* visible,
5193 // diagnose that it was declared too late.
5194
5195 TemplateParameterList *Params = TD->getTemplateParameters();
5196
5197 S.Diag(Loc, diag::err_template_arg_list_different_arity)
5198 << /*not enough args*/0
5199 << (int)S.getTemplateNameKindForDiagnostics(TemplateName(TD))
5200 << TD;
5201 S.Diag(TD->getLocation(), diag::note_template_decl_here)
5202 << Params->getSourceRange();
5203 return true;
5204}
5205
5206/// Check that the given template argument list is well-formed
5207/// for specializing the given template.
5208bool Sema::CheckTemplateArgumentList(
5209 TemplateDecl *Template, SourceLocation TemplateLoc,
5210 TemplateArgumentListInfo &TemplateArgs, bool PartialTemplateArgs,
5211 SmallVectorImpl<TemplateArgument> &Converted,
5212 bool UpdateArgsWithConversions) {
5213 // Make a copy of the template arguments for processing. Only make the
5214 // changes at the end when successful in matching the arguments to the
5215 // template.
5216 TemplateArgumentListInfo NewArgs = TemplateArgs;
5217
5218 // Make sure we get the template parameter list from the most
5219 // recentdeclaration, since that is the only one that has is guaranteed to
5220 // have all the default template argument information.
5221 TemplateParameterList *Params =
5222 cast<TemplateDecl>(Template->getMostRecentDecl())
5223 ->getTemplateParameters();
5224
5225 SourceLocation RAngleLoc = NewArgs.getRAngleLoc();
5226
5227 // C++ [temp.arg]p1:
5228 // [...] The type and form of each template-argument specified in
5229 // a template-id shall match the type and form specified for the
5230 // corresponding parameter declared by the template in its
5231 // template-parameter-list.
5232 bool isTemplateTemplateParameter = isa<TemplateTemplateParmDecl>(Template);
5233 SmallVector<TemplateArgument, 2> ArgumentPack;
5234 unsigned ArgIdx = 0, NumArgs = NewArgs.size();
5235 LocalInstantiationScope InstScope(*this, true);
5236 for (TemplateParameterList::iterator Param = Params->begin(),
5237 ParamEnd = Params->end();
5238 Param != ParamEnd; /* increment in loop */) {
5239 // If we have an expanded parameter pack, make sure we don't have too
5240 // many arguments.
5241 if (Optional<unsigned> Expansions = getExpandedPackSize(*Param)) {
5242 if (*Expansions == ArgumentPack.size()) {
5243 // We're done with this parameter pack. Pack up its arguments and add
5244 // them to the list.
5245 Converted.push_back(
5246 TemplateArgument::CreatePackCopy(Context, ArgumentPack));
5247 ArgumentPack.clear();
5248
5249 // This argument is assigned to the next parameter.
5250 ++Param;
5251 continue;
5252 } else if (ArgIdx == NumArgs && !PartialTemplateArgs) {
5253 // Not enough arguments for this parameter pack.
5254 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
5255 << /*not enough args*/0
5256 << (int)getTemplateNameKindForDiagnostics(TemplateName(Template))
5257 << Template;
5258 Diag(Template->getLocation(), diag::note_template_decl_here)
5259 << Params->getSourceRange();
5260 return true;
5261 }
5262 }
5263
5264 if (ArgIdx < NumArgs) {
5265 // Check the template argument we were given.
5266 if (CheckTemplateArgument(*Param, NewArgs[ArgIdx], Template,
5267 TemplateLoc, RAngleLoc,
5268 ArgumentPack.size(), Converted))
5269 return true;
5270
5271 bool PackExpansionIntoNonPack =
5272 NewArgs[ArgIdx].getArgument().isPackExpansion() &&
5273 (!(*Param)->isTemplateParameterPack() || getExpandedPackSize(*Param));
5274 if (PackExpansionIntoNonPack && isa<TypeAliasTemplateDecl>(Template)) {
5275 // Core issue 1430: we have a pack expansion as an argument to an
5276 // alias template, and it's not part of a parameter pack. This
5277 // can't be canonicalized, so reject it now.
5278 Diag(NewArgs[ArgIdx].getLocation(),
5279 diag::err_alias_template_expansion_into_fixed_list)
5280 << NewArgs[ArgIdx].getSourceRange();
5281 Diag((*Param)->getLocation(), diag::note_template_param_here);
5282 return true;
5283 }
5284
5285 // We're now done with this argument.
5286 ++ArgIdx;
5287
5288 if ((*Param)->isTemplateParameterPack()) {
5289 // The template parameter was a template parameter pack, so take the
5290 // deduced argument and place it on the argument pack. Note that we
5291 // stay on the same template parameter so that we can deduce more
5292 // arguments.
5293 ArgumentPack.push_back(Converted.pop_back_val());
5294 } else {
5295 // Move to the next template parameter.
5296 ++Param;
5297 }
5298
5299 // If we just saw a pack expansion into a non-pack, then directly convert
5300 // the remaining arguments, because we don't know what parameters they'll
5301 // match up with.
5302 if (PackExpansionIntoNonPack) {
5303 if (!ArgumentPack.empty()) {
5304 // If we were part way through filling in an expanded parameter pack,
5305 // fall back to just producing individual arguments.
5306 Converted.insert(Converted.end(),
5307 ArgumentPack.begin(), ArgumentPack.end());
5308 ArgumentPack.clear();
5309 }
5310
5311 while (ArgIdx < NumArgs) {
5312 Converted.push_back(NewArgs[ArgIdx].getArgument());
5313 ++ArgIdx;
5314 }
5315
5316 return false;
5317 }
5318
5319 continue;
5320 }
5321
5322 // If we're checking a partial template argument list, we're done.
5323 if (PartialTemplateArgs) {
5324 if ((*Param)->isTemplateParameterPack() && !ArgumentPack.empty())
5325 Converted.push_back(
5326 TemplateArgument::CreatePackCopy(Context, ArgumentPack));
5327
5328 return false;
5329 }
5330
5331 // If we have a template parameter pack with no more corresponding
5332 // arguments, just break out now and we'll fill in the argument pack below.
5333 if ((*Param)->isTemplateParameterPack()) {
5334 assert(!getExpandedPackSize(*Param) &&((!getExpandedPackSize(*Param) && "Should have dealt with this already"
) ? static_cast<void> (0) : __assert_fail ("!getExpandedPackSize(*Param) && \"Should have dealt with this already\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5335, __PRETTY_FUNCTION__))
5335 "Should have dealt with this already")((!getExpandedPackSize(*Param) && "Should have dealt with this already"
) ? static_cast<void> (0) : __assert_fail ("!getExpandedPackSize(*Param) && \"Should have dealt with this already\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5335, __PRETTY_FUNCTION__))
;
5336
5337 // A non-expanded parameter pack before the end of the parameter list
5338 // only occurs for an ill-formed template parameter list, unless we've
5339 // got a partial argument list for a function template, so just bail out.
5340 if (Param + 1 != ParamEnd)
5341 return true;
5342
5343 Converted.push_back(
5344 TemplateArgument::CreatePackCopy(Context, ArgumentPack));
5345 ArgumentPack.clear();
5346
5347 ++Param;
5348 continue;
5349 }
5350
5351 // Check whether we have a default argument.
5352 TemplateArgumentLoc Arg;
5353
5354 // Retrieve the default template argument from the template
5355 // parameter. For each kind of template parameter, we substitute the
5356 // template arguments provided thus far and any "outer" template arguments
5357 // (when the template parameter was part of a nested template) into
5358 // the default argument.
5359 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
5360 if (!hasVisibleDefaultArgument(TTP))
5361 return diagnoseMissingArgument(*this, TemplateLoc, Template, TTP,
5362 NewArgs);
5363
5364 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
5365 Template,
5366 TemplateLoc,
5367 RAngleLoc,
5368 TTP,
5369 Converted);
5370 if (!ArgType)
5371 return true;
5372
5373 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
5374 ArgType);
5375 } else if (NonTypeTemplateParmDecl *NTTP
5376 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
5377 if (!hasVisibleDefaultArgument(NTTP))
5378 return diagnoseMissingArgument(*this, TemplateLoc, Template, NTTP,
5379 NewArgs);
5380
5381 ExprResult E = SubstDefaultTemplateArgument(*this, Template,
5382 TemplateLoc,
5383 RAngleLoc,
5384 NTTP,
5385 Converted);
5386 if (E.isInvalid())
5387 return true;
5388
5389 Expr *Ex = E.getAs<Expr>();
5390 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
5391 } else {
5392 TemplateTemplateParmDecl *TempParm
5393 = cast<TemplateTemplateParmDecl>(*Param);
5394
5395 if (!hasVisibleDefaultArgument(TempParm))
5396 return diagnoseMissingArgument(*this, TemplateLoc, Template, TempParm,
5397 NewArgs);
5398
5399 NestedNameSpecifierLoc QualifierLoc;
5400 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
5401 TemplateLoc,
5402 RAngleLoc,
5403 TempParm,
5404 Converted,
5405 QualifierLoc);
5406 if (Name.isNull())
5407 return true;
5408
5409 Arg = TemplateArgumentLoc(TemplateArgument(Name), QualifierLoc,
5410 TempParm->getDefaultArgument().getTemplateNameLoc());
5411 }
5412
5413 // Introduce an instantiation record that describes where we are using
5414 // the default template argument. We're not actually instantiating a
5415 // template here, we just create this object to put a note into the
5416 // context stack.
5417 InstantiatingTemplate Inst(*this, RAngleLoc, Template, *Param, Converted,
5418 SourceRange(TemplateLoc, RAngleLoc));
5419 if (Inst.isInvalid())
5420 return true;
5421
5422 // Check the default template argument.
5423 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
5424 RAngleLoc, 0, Converted))
5425 return true;
5426
5427 // Core issue 150 (assumed resolution): if this is a template template
5428 // parameter, keep track of the default template arguments from the
5429 // template definition.
5430 if (isTemplateTemplateParameter)
5431 NewArgs.addArgument(Arg);
5432
5433 // Move to the next template parameter and argument.
5434 ++Param;
5435 ++ArgIdx;
5436 }
5437
5438 // If we're performing a partial argument substitution, allow any trailing
5439 // pack expansions; they might be empty. This can happen even if
5440 // PartialTemplateArgs is false (the list of arguments is complete but
5441 // still dependent).
5442 if (ArgIdx < NumArgs && CurrentInstantiationScope &&
5443 CurrentInstantiationScope->getPartiallySubstitutedPack()) {
5444 while (ArgIdx < NumArgs && NewArgs[ArgIdx].getArgument().isPackExpansion())
5445 Converted.push_back(NewArgs[ArgIdx++].getArgument());
5446 }
5447
5448 // If we have any leftover arguments, then there were too many arguments.
5449 // Complain and fail.
5450 if (ArgIdx < NumArgs) {
5451 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
5452 << /*too many args*/1
5453 << (int)getTemplateNameKindForDiagnostics(TemplateName(Template))
5454 << Template
5455 << SourceRange(NewArgs[ArgIdx].getLocation(), NewArgs.getRAngleLoc());
5456 Diag(Template->getLocation(), diag::note_template_decl_here)
5457 << Params->getSourceRange();
5458 return true;
5459 }
5460
5461 // No problems found with the new argument list, propagate changes back
5462 // to caller.
5463 if (UpdateArgsWithConversions)
5464 TemplateArgs = std::move(NewArgs);
5465
5466 return false;
5467}
5468
5469namespace {
5470 class UnnamedLocalNoLinkageFinder
5471 : public TypeVisitor<UnnamedLocalNoLinkageFinder, bool>
5472 {
5473 Sema &S;
5474 SourceRange SR;
5475
5476 typedef TypeVisitor<UnnamedLocalNoLinkageFinder, bool> inherited;
5477
5478 public:
5479 UnnamedLocalNoLinkageFinder(Sema &S, SourceRange SR) : S(S), SR(SR) { }
5480
5481 bool Visit(QualType T) {
5482 return T.isNull() ? false : inherited::Visit(T.getTypePtr());
5483 }
5484
5485#define TYPE(Class, Parent) \
5486 bool Visit##Class##Type(const Class##Type *);
5487#define ABSTRACT_TYPE(Class, Parent) \
5488 bool Visit##Class##Type(const Class##Type *) { return false; }
5489#define NON_CANONICAL_TYPE(Class, Parent) \
5490 bool Visit##Class##Type(const Class##Type *) { return false; }
5491#include "clang/AST/TypeNodes.inc"
5492
5493 bool VisitTagDecl(const TagDecl *Tag);
5494 bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS);
5495 };
5496} // end anonymous namespace
5497
5498bool UnnamedLocalNoLinkageFinder::VisitBuiltinType(const BuiltinType*) {
5499 return false;
5500}
5501
5502bool UnnamedLocalNoLinkageFinder::VisitComplexType(const ComplexType* T) {
5503 return Visit(T->getElementType());
5504}
5505
5506bool UnnamedLocalNoLinkageFinder::VisitPointerType(const PointerType* T) {
5507 return Visit(T->getPointeeType());
5508}
5509
5510bool UnnamedLocalNoLinkageFinder::VisitBlockPointerType(
5511 const BlockPointerType* T) {
5512 return Visit(T->getPointeeType());
5513}
5514
5515bool UnnamedLocalNoLinkageFinder::VisitLValueReferenceType(
5516 const LValueReferenceType* T) {
5517 return Visit(T->getPointeeType());
5518}
5519
5520bool UnnamedLocalNoLinkageFinder::VisitRValueReferenceType(
5521 const RValueReferenceType* T) {
5522 return Visit(T->getPointeeType());
5523}
5524
5525bool UnnamedLocalNoLinkageFinder::VisitMemberPointerType(
5526 const MemberPointerType* T) {
5527 return Visit(T->getPointeeType()) || Visit(QualType(T->getClass(), 0));
5528}
5529
5530bool UnnamedLocalNoLinkageFinder::VisitConstantArrayType(
5531 const ConstantArrayType* T) {
5532 return Visit(T->getElementType());
5533}
5534
5535bool UnnamedLocalNoLinkageFinder::VisitIncompleteArrayType(
5536 const IncompleteArrayType* T) {
5537 return Visit(T->getElementType());
5538}
5539
5540bool UnnamedLocalNoLinkageFinder::VisitVariableArrayType(
5541 const VariableArrayType* T) {
5542 return Visit(T->getElementType());
5543}
5544
5545bool UnnamedLocalNoLinkageFinder::VisitDependentSizedArrayType(
5546 const DependentSizedArrayType* T) {
5547 return Visit(T->getElementType());
5548}
5549
5550bool UnnamedLocalNoLinkageFinder::VisitDependentSizedExtVectorType(
5551 const DependentSizedExtVectorType* T) {
5552 return Visit(T->getElementType());
5553}
5554
5555bool UnnamedLocalNoLinkageFinder::VisitDependentAddressSpaceType(
5556 const DependentAddressSpaceType *T) {
5557 return Visit(T->getPointeeType());
5558}
5559
5560bool UnnamedLocalNoLinkageFinder::VisitVectorType(const VectorType* T) {
5561 return Visit(T->getElementType());
5562}
5563
5564bool UnnamedLocalNoLinkageFinder::VisitDependentVectorType(
5565 const DependentVectorType *T) {
5566 return Visit(T->getElementType());
5567}
5568
5569bool UnnamedLocalNoLinkageFinder::VisitExtVectorType(const ExtVectorType* T) {
5570 return Visit(T->getElementType());
5571}
5572
5573bool UnnamedLocalNoLinkageFinder::VisitFunctionProtoType(
5574 const FunctionProtoType* T) {
5575 for (const auto &A : T->param_types()) {
5576 if (Visit(A))
5577 return true;
5578 }
5579
5580 return Visit(T->getReturnType());
5581}
5582
5583bool UnnamedLocalNoLinkageFinder::VisitFunctionNoProtoType(
5584 const FunctionNoProtoType* T) {
5585 return Visit(T->getReturnType());
5586}
5587
5588bool UnnamedLocalNoLinkageFinder::VisitUnresolvedUsingType(
5589 const UnresolvedUsingType*) {
5590 return false;
5591}
5592
5593bool UnnamedLocalNoLinkageFinder::VisitTypeOfExprType(const TypeOfExprType*) {
5594 return false;
5595}
5596
5597bool UnnamedLocalNoLinkageFinder::VisitTypeOfType(const TypeOfType* T) {
5598 return Visit(T->getUnderlyingType());
5599}
5600
5601bool UnnamedLocalNoLinkageFinder::VisitDecltypeType(const DecltypeType*) {
5602 return false;
5603}
5604
5605bool UnnamedLocalNoLinkageFinder::VisitUnaryTransformType(
5606 const UnaryTransformType*) {
5607 return false;
5608}
5609
5610bool UnnamedLocalNoLinkageFinder::VisitAutoType(const AutoType *T) {
5611 return Visit(T->getDeducedType());
5612}
5613
5614bool UnnamedLocalNoLinkageFinder::VisitDeducedTemplateSpecializationType(
5615 const DeducedTemplateSpecializationType *T) {
5616 return Visit(T->getDeducedType());
5617}
5618
5619bool UnnamedLocalNoLinkageFinder::VisitRecordType(const RecordType* T) {
5620 return VisitTagDecl(T->getDecl());
5621}
5622
5623bool UnnamedLocalNoLinkageFinder::VisitEnumType(const EnumType* T) {
5624 return VisitTagDecl(T->getDecl());
5625}
5626
5627bool UnnamedLocalNoLinkageFinder::VisitTemplateTypeParmType(
5628 const TemplateTypeParmType*) {
5629 return false;
5630}
5631
5632bool UnnamedLocalNoLinkageFinder::VisitSubstTemplateTypeParmPackType(
5633 const SubstTemplateTypeParmPackType *) {
5634 return false;
5635}
5636
5637bool UnnamedLocalNoLinkageFinder::VisitTemplateSpecializationType(
5638 const TemplateSpecializationType*) {
5639 return false;
5640}
5641
5642bool UnnamedLocalNoLinkageFinder::VisitInjectedClassNameType(
5643 const InjectedClassNameType* T) {
5644 return VisitTagDecl(T->getDecl());
5645}
5646
5647bool UnnamedLocalNoLinkageFinder::VisitDependentNameType(
5648 const DependentNameType* T) {
5649 return VisitNestedNameSpecifier(T->getQualifier());
5650}
5651
5652bool UnnamedLocalNoLinkageFinder::VisitDependentTemplateSpecializationType(
5653 const DependentTemplateSpecializationType* T) {
5654 return VisitNestedNameSpecifier(T->getQualifier());
5655}
5656
5657bool UnnamedLocalNoLinkageFinder::VisitPackExpansionType(
5658 const PackExpansionType* T) {
5659 return Visit(T->getPattern());
5660}
5661
5662bool UnnamedLocalNoLinkageFinder::VisitObjCObjectType(const ObjCObjectType *) {
5663 return false;
5664}
5665
5666bool UnnamedLocalNoLinkageFinder::VisitObjCInterfaceType(
5667 const ObjCInterfaceType *) {
5668 return false;
5669}
5670
5671bool UnnamedLocalNoLinkageFinder::VisitObjCObjectPointerType(
5672 const ObjCObjectPointerType *) {
5673 return false;
5674}
5675
5676bool UnnamedLocalNoLinkageFinder::VisitAtomicType(const AtomicType* T) {
5677 return Visit(T->getValueType());
5678}
5679
5680bool UnnamedLocalNoLinkageFinder::VisitPipeType(const PipeType* T) {
5681 return false;
5682}
5683
5684bool UnnamedLocalNoLinkageFinder::VisitTagDecl(const TagDecl *Tag) {
5685 if (Tag->getDeclContext()->isFunctionOrMethod()) {
5686 S.Diag(SR.getBegin(),
5687 S.getLangOpts().CPlusPlus11 ?
5688 diag::warn_cxx98_compat_template_arg_local_type :
5689 diag::ext_template_arg_local_type)
5690 << S.Context.getTypeDeclType(Tag) << SR;
5691 return true;
5692 }
5693
5694 if (!Tag->hasNameForLinkage()) {
5695 S.Diag(SR.getBegin(),
5696 S.getLangOpts().CPlusPlus11 ?
5697 diag::warn_cxx98_compat_template_arg_unnamed_type :
5698 diag::ext_template_arg_unnamed_type) << SR;
5699 S.Diag(Tag->getLocation(), diag::note_template_unnamed_type_here);
5700 return true;
5701 }
5702
5703 return false;
5704}
5705
5706bool UnnamedLocalNoLinkageFinder::VisitNestedNameSpecifier(
5707 NestedNameSpecifier *NNS) {
5708 if (NNS->getPrefix() && VisitNestedNameSpecifier(NNS->getPrefix()))
5709 return true;
5710
5711 switch (NNS->getKind()) {
5712 case NestedNameSpecifier::Identifier:
5713 case NestedNameSpecifier::Namespace:
5714 case NestedNameSpecifier::NamespaceAlias:
5715 case NestedNameSpecifier::Global:
5716 case NestedNameSpecifier::Super:
5717 return false;
5718
5719 case NestedNameSpecifier::TypeSpec:
5720 case NestedNameSpecifier::TypeSpecWithTemplate:
5721 return Visit(QualType(NNS->getAsType(), 0));
5722 }
5723 llvm_unreachable("Invalid NestedNameSpecifier::Kind!")::llvm::llvm_unreachable_internal("Invalid NestedNameSpecifier::Kind!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5723)
;
5724}
5725
5726/// Check a template argument against its corresponding
5727/// template type parameter.
5728///
5729/// This routine implements the semantics of C++ [temp.arg.type]. It
5730/// returns true if an error occurred, and false otherwise.
5731bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
5732 TypeSourceInfo *ArgInfo) {
5733 assert(ArgInfo && "invalid TypeSourceInfo")((ArgInfo && "invalid TypeSourceInfo") ? static_cast<
void> (0) : __assert_fail ("ArgInfo && \"invalid TypeSourceInfo\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5733, __PRETTY_FUNCTION__))
;
5734 QualType Arg = ArgInfo->getType();
5735 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
5736
5737 if (Arg->isVariablyModifiedType()) {
5738 return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg;
5739 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
5740 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
5741 }
5742
5743 // C++03 [temp.arg.type]p2:
5744 // A local type, a type with no linkage, an unnamed type or a type
5745 // compounded from any of these types shall not be used as a
5746 // template-argument for a template type-parameter.
5747 //
5748 // C++11 allows these, and even in C++03 we allow them as an extension with
5749 // a warning.
5750 if (LangOpts.CPlusPlus11 || Arg->hasUnnamedOrLocalType()) {
5751 UnnamedLocalNoLinkageFinder Finder(*this, SR);
5752 (void)Finder.Visit(Context.getCanonicalType(Arg));
5753 }
5754
5755 return false;
5756}
5757
5758enum NullPointerValueKind {
5759 NPV_NotNullPointer,
5760 NPV_NullPointer,
5761 NPV_Error
5762};
5763
5764/// Determine whether the given template argument is a null pointer
5765/// value of the appropriate type.
5766static NullPointerValueKind
5767isNullPointerValueTemplateArgument(Sema &S, NonTypeTemplateParmDecl *Param,
5768 QualType ParamType, Expr *Arg,
5769 Decl *Entity = nullptr) {
5770 if (Arg->isValueDependent() || Arg->isTypeDependent())
5771 return NPV_NotNullPointer;
5772
5773 // dllimport'd entities aren't constant but are available inside of template
5774 // arguments.
5775 if (Entity && Entity->hasAttr<DLLImportAttr>())
5776 return NPV_NotNullPointer;
5777
5778 if (!S.isCompleteType(Arg->getExprLoc(), ParamType))
5779 llvm_unreachable(::llvm::llvm_unreachable_internal("Incomplete parameter type in isNullPointerValueTemplateArgument!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5780)
5780 "Incomplete parameter type in isNullPointerValueTemplateArgument!")::llvm::llvm_unreachable_internal("Incomplete parameter type in isNullPointerValueTemplateArgument!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/clang/lib/Sema/SemaTemplate.cpp"
, 5780)
;
5781
5782 if (!S.getLangOpts().CPlusPlus11)
5783 return NPV_NotNullPointer;
5784
5785 // Determine whether we have a constant expression.
5786 ExprResult ArgRV = S.DefaultFunctionArrayConversion(Arg);
5787 if (ArgRV.isInvalid())
5788 return NPV_Error;
5789 Arg = ArgRV.get();
5790
5791 Expr::EvalResult EvalResult;
5792 SmallVector<PartialDiagnosticAt, 8> Notes;
5793 EvalResult.Diag = &Notes;
5794 if (!Arg->EvaluateAsRValue(EvalResult, S.Context) ||
5795 EvalResult.HasSideEffects) {
5796 SourceLocation DiagLoc = Arg->getExprLoc();
5797
5798 // If our only note is the usual "invalid subexpression" note, just point
5799 // the caret at its location rather than producing an essentially
5800 // redundant note.
5801 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
5802 diag::note_invalid_subexpr_in_const_expr) {
5803 DiagLoc = Notes[0].first;
5804 Notes.clear();
5805 }
5806
5807 S.Diag(DiagLoc, diag::err_template_arg_not_address_constant)
5808 << Arg->getType() << Arg->getSourceRange();
5809 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
5810 S.Diag(Notes[I].first, Notes[I].second);
5811
5812 S.Diag(Param->getLocation(), diag::note_template_param_here);
5813 return NPV_Error;
5814 }
5815
5816 // C++11 [temp.arg.nontype]p1:
5817 // - an address constant expression of type std::nullptr_t
5818 if (Arg->getType()->isNullPtrType())
5819 return NPV_NullPointer;
5820
5821 // - a constant expression that evaluates to a null pointer value (4.10); or
5822 // - a constant expression that evaluates to a null member pointer value
5823 // (4.11); or
5824 if ((EvalResult.Val.isLValue() && !EvalResult.Val.getLValueBase()) ||
5825 (EvalResult.Val.isMemberPointer() &&
5826 !EvalResult.Val.getMemberPointerDecl())) {
5827 // If our expression has an appropriate type, we've succeeded.
5828 bool ObjCLifetimeConversion;
5829 if (S.Context.hasSameUnqualifiedType(Arg->getType(), ParamType) ||
5830 S.IsQualificationConversion(Arg->getType(), ParamType, false,
5831 ObjCLifetimeConversion))
5832 return NPV_NullPointer;
5833
5834 // The types didn't match, but we know we got a null pointer; complain,
5835 // then recover as if the types were correct.
5836 S.Diag(Arg->getExprLoc(), diag::err_template_arg_wrongtype_null_constant)
5837 << Arg->getType() << ParamType << Arg->getSourceRange();
5838 S.Diag(Param->getLocation(), diag::note_template_param_here);
5839 return NPV_NullPointer;
5840 }
5841
5842 // If we don't have a null pointer value, but we do have a NULL pointer
5843 // constant, suggest a cast to the appropriate type.
5844 if (Arg->isNullPointerConstant(S.Context, Expr::NPC_NeverValueDependent)) {
5845 std::string Code = "static_cast<" + ParamType.getAsString() + ">(";
5846 S.Diag(Arg->getExprLoc(), diag::err_template_arg_untyped_null_constant)
5847 << ParamType << FixItHint::CreateInsertion(Arg->getBeginLoc(), Code)
5848 << FixItHint::CreateInsertion(S.getLocForEndOfToken(Arg->getEndLoc()),
5849 ")");
5850 S.Diag(Param->getLocation(), diag::note_template_param_here);
5851 return NPV_NullPointer;
5852 }
5853
5854 // FIXME: If we ever want to support general, address-constant expressions
5855 // as non-type template arguments, we should return the ExprResult here to
5856 // be interpreted by the caller.
5857 return NPV_NotNullPointer;
5858}
5859
5860/// Checks whether the given template argument is compatible with its
5861/// template parameter.
5862static bool CheckTemplateArgumentIsCompatibleWithParameter(
5863 Sema &S, NonTypeTemplateParmDecl *Param, QualType ParamType, Expr *ArgIn,
5864 Expr *Arg, QualType ArgType) {
5865 bool ObjCLifetimeConversion;
5866 if (ParamType->isPointerType() &&
5867 !ParamType->castAs<PointerType>()->getPointeeType()->isFunctionType() &&
5868 S.IsQualificationConversion(ArgType, ParamType, false,
5869 ObjCLifetimeConversion)) {
5870 // For pointer-to-object types, qualification conversions are
5871 // permitted.
5872 } else {
5873 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
5874 if (!ParamRef->getPointeeType()->isFunctionType()) {
5875 // C++ [temp.arg.nontype]p5b3:
5876 // For a non-type template-parameter of type reference to
5877 // object, no conversions apply. The type referred to by the
5878 // reference may be more cv-qualified than the (otherwise
5879 // identical) type of the template- argument. The
5880 // template-parameter is bound directly to the
5881 // template-argument, which shall be an lvalue.
5882
5883 // FIXME: Other qualifiers?
5884 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
5885 unsigned ArgQuals = ArgType.getCVRQualifiers();
5886
5887 if ((ParamQuals | ArgQuals) != ParamQuals) {
5888 S.Diag(Arg->getBeginLoc(),
5889 diag::err_template_arg_ref_bind_ignores_quals)
5890 << ParamType << Arg->getType() << Arg->getSourceRange();
5891 S.Diag(Param->getLocation(), diag::note_template_param_here);
5892 return true;
5893 }
5894 }
5895 }
5896
5897 // At this point, the template argument refers to an object or
5898 // function with external linkage. We now need to check whether the
5899 // argument and parameter types are compatible.
5900 if (!S.Context.hasSameUnqualifiedType(ArgType,
5901 ParamType.getNonReferenceType())) {
5902 // We can't perform this conversion or binding.
5903 if (ParamType->isReferenceType())
5904 S.Diag(Arg->getBeginLoc(), diag::err_template_arg_no_ref_bind)
5905 << ParamType << ArgIn->getType() << Arg->getSourceRange();
5906 else
5907 S.Diag(Arg->getBeginLoc(), diag::err_template_arg_not_convertible)
5908 << ArgIn->getType() << ParamType << Arg->getSourceRange();
5909 S.Diag(Param->getLocation(), diag::note_template_param_here);
5910 return true;
5911 }
5912 }
5913
5914 return false;
5915}
5916
5917/// Checks whether the given template argument is the address
5918/// of an object or function according to C++ [temp.arg.nontype]p1.
5919static bool
5920CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
5921 NonTypeTemplateParmDecl *Param,
5922 QualType ParamType,
5923 Expr *ArgIn,
5924 TemplateArgument &Converted) {
5925 bool Invalid = false;
5926 Expr *Arg = ArgIn;
5927 QualType ArgType = Arg->getType();
5928
5929 bool AddressTaken = false;
5930 SourceLocation AddrOpLoc;
5931 if (S.getLangOpts().MicrosoftExt) {
5932 // Microsoft Visual C++ strips all casts, allows an arbitrary number of
5933 // dereference and address-of operators.
5934 Arg = Arg->IgnoreParenCasts();
5935
5936 bool ExtWarnMSTemplateArg = false;
5937 UnaryOperatorKind FirstOpKind;
5938 SourceLocation FirstOpLoc;
5939 while (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
5940 UnaryOperatorKind UnOpKind = UnOp->getOpcode();
5941 if (UnOpKind == UO_Deref)