Skip to content

Commit 616b2cf

Browse files
sdkrystiansdkrystian
committed
[WIP][Clang] Implement resolution for CWG1835
1 parent ed25d1a commit 616b2cf

File tree

15 files changed

+127
-64
lines changed

15 files changed

+127
-64
lines changed

‎clang/include/clang/Sema/DeclSpec.h

Lines changed: 8 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -75,6 +75,7 @@ class CXXScopeSpec {
7575
SourceRange Range;
7676
NestedNameSpecifierLocBuilder Builder;
7777
ArrayRef<TemplateParameterList *> TemplateParamLists;
78+
NamedDecl *FoundFirstQualifierInScope;
7879

7980
public:
8081
SourceRange getRange() const { return Range; }
@@ -91,6 +92,13 @@ class CXXScopeSpec {
9192
return TemplateParamLists;
9293
}
9394

95+
void setFoundFirstQualifierInScope(NamedDecl *Found) {
96+
FoundFirstQualifierInScope = Found;
97+
}
98+
NamedDecl *getFirstQualifierFoundInScope() const {
99+
return FoundFirstQualifierInScope;
100+
}
101+
94102
/// Retrieve the representation of the nested-name-specifier.
95103
NestedNameSpecifier *getScopeRep() const {
96104
return Builder.getRepresentation();

‎clang/include/clang/Sema/Sema.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -6920,7 +6920,7 @@ class Sema final : public SemaBase {
69206920
const TemplateArgumentListInfo *TemplateArgs);
69216921

69226922
ExprResult ActOnMemberAccessExpr(Scope *S, Expr *Base, SourceLocation OpLoc,
6923-
tok::TokenKind OpKind, CXXScopeSpec &SS,
6923+
bool IsArrow, CXXScopeSpec &SS,
69246924
SourceLocation TemplateKWLoc,
69256925
UnqualifiedId &Member, Decl *ObjCImpDecl);
69266926

‎clang/lib/Parse/ParseDeclCXX.cpp

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -720,7 +720,7 @@ Parser::DeclGroupPtrTy Parser::ParseUsingDeclaration(
720720
return nullptr;
721721
}
722722
CXXScopeSpec SS;
723-
if (ParseOptionalCXXScopeSpecifier(SS, /*ParsedType=*/nullptr,
723+
if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
724724
/*ObectHasErrors=*/false,
725725
/*EnteringConttext=*/false,
726726
/*MayBePseudoDestructor=*/nullptr,

‎clang/lib/Parse/ParseExpr.cpp

Lines changed: 5 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -2254,6 +2254,7 @@ Parser::ParsePostfixExpressionSuffix(ExprResult LHS) {
22542254
}
22552255
break;
22562256
}
2257+
22572258
ParseOptionalCXXScopeSpecifier(
22582259
SS, ObjectType, LHS.get() && LHS.get()->containsErrors(),
22592260
/*EnteringContext=*/false, &MayBePseudoDestructor);
@@ -2328,10 +2329,10 @@ Parser::ParsePostfixExpressionSuffix(ExprResult LHS) {
23282329
}
23292330

23302331
if (!LHS.isInvalid())
2331-
LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.get(), OpLoc,
2332-
OpKind, SS, TemplateKWLoc, Name,
2333-
CurParsedObjCImpl ? CurParsedObjCImpl->Dcl
2334-
: nullptr);
2332+
LHS = Actions.ActOnMemberAccessExpr(
2333+
getCurScope(), LHS.get(), OpLoc, OpKind == tok::arrow, SS,
2334+
TemplateKWLoc, Name,
2335+
CurParsedObjCImpl ? CurParsedObjCImpl->Dcl : nullptr);
23352336
if (!LHS.isInvalid()) {
23362337
if (Tok.is(tok::less))
23372338
checkPotentialAngleBracket(LHS);

‎clang/lib/Sema/SemaCXXScopeSpec.cpp

Lines changed: 43 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -397,22 +397,30 @@ NamedDecl *Sema::FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS) {
397397
while (NNS->getPrefix())
398398
NNS = NNS->getPrefix();
399399

400-
if (NNS->getKind() != NestedNameSpecifier::Identifier)
401-
return nullptr;
402-
403-
LookupResult Found(*this, NNS->getAsIdentifier(), SourceLocation(),
404-
LookupNestedNameSpecifierName);
400+
const IdentifierInfo *II = NNS->getAsIdentifier();
401+
if (!II) {
402+
if (const auto *DTST =
403+
dyn_cast_if_present<DependentTemplateSpecializationType>(
404+
NNS->getAsType()))
405+
II = DTST->getIdentifier();
406+
else
407+
return nullptr;
408+
}
409+
assert(II && "Missing first qualifier in scope");
410+
LookupResult Found(*this, II, SourceLocation(),
411+
NNS->getAsIdentifier() ? LookupNestedNameSpecifierName
412+
: LookupOrdinaryName);
405413
LookupName(Found, S);
406414
assert(!Found.isAmbiguous() && "Cannot handle ambiguities here yet");
407415

408416
if (!Found.isSingleResult())
409417
return nullptr;
410418

411419
NamedDecl *Result = Found.getFoundDecl();
412-
if (isAcceptableNestedNameSpecifier(Result))
413-
return Result;
420+
// if (isAcceptableNestedNameSpecifier(Result))
421+
return Result;
414422

415-
return nullptr;
423+
// return nullptr;
416424
}
417425

418426
namespace {
@@ -493,12 +501,15 @@ bool Sema::BuildCXXNestedNameSpecifier(Scope *S, NestedNameSpecInfo &IdInfo,
493501
// x->B::f, and we are looking into the type of the object.
494502
assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
495503
LookupCtx = computeDeclContext(ObjectType);
496-
isDependent = ObjectType->isDependentType();
497-
} else if (SS.isSet()) {
504+
isDependent = !LookupCtx && ObjectType->isDependentType();
505+
} else if (SS.isNotEmpty()) {
498506
// This nested-name-specifier occurs after another nested-name-specifier,
499507
// so look into the context associated with the prior nested-name-specifier.
500508
LookupCtx = computeDeclContext(SS, EnteringContext);
501-
isDependent = isDependentScopeSpecifier(SS);
509+
isDependent = !LookupCtx && isDependentScopeSpecifier(SS);
510+
// The declaration context must be complete.
511+
if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
512+
return true;
502513
Found.setContextRange(SS.getRange());
503514
}
504515

@@ -509,14 +520,28 @@ bool Sema::BuildCXXNestedNameSpecifier(Scope *S, NestedNameSpecInfo &IdInfo,
509520
// expression or the declaration context associated with a prior
510521
// nested-name-specifier.
511522

512-
// The declaration context must be complete.
513-
if (!LookupCtx->isDependentContext() &&
514-
RequireCompleteDeclContext(SS, LookupCtx))
515-
return true;
516-
517523
LookupQualifiedName(Found, LookupCtx);
518524

519-
if (!ObjectType.isNull() && Found.empty()) {
525+
isDependent |= Found.wasNotFoundInCurrentInstantiation();
526+
}
527+
528+
bool LookupFirstQualifierInScope =
529+
Found.empty() && !ObjectType.isNull() && !isDependent;
530+
531+
// FIXME: We should still do the lookup if the object expression is dependent,
532+
// but instead of using them we should store them via
533+
// setFirstQualifierFoundInScope and pretend we found nothing.
534+
if (SS.isEmpty() && (ObjectType.isNull() || LookupFirstQualifierInScope)) {
535+
if (S)
536+
LookupName(Found, S);
537+
else if (LookupFirstQualifierInScope && SS.getFirstQualifierFoundInScope())
538+
Found.addDecl(SS.getFirstQualifierFoundInScope());
539+
540+
if (!ObjectType.isNull())
541+
ObjectTypeSearchedInScope = true;
542+
}
543+
#if 0
544+
if (!ObjectType.isNull() && Found.empty() && !isDependent) {
520545
// C++ [basic.lookup.classref]p4:
521546
// If the id-expression in a class member access is a qualified-id of
522547
// the form
@@ -548,6 +573,7 @@ bool Sema::BuildCXXNestedNameSpecifier(Scope *S, NestedNameSpecInfo &IdInfo,
548573
// Perform unqualified name lookup in the current scope.
549574
LookupName(Found, S);
550575
}
576+
#endif
551577

552578
if (Found.isAmbiguous())
553579
return true;

‎clang/lib/Sema/SemaExprMember.cpp

Lines changed: 3 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -1054,7 +1054,7 @@ Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
10541054
if (RetryExpr.isUsable() && !Trap.hasErrorOccurred()) {
10551055
CXXScopeSpec TempSS(SS);
10561056
RetryExpr = ActOnMemberAccessExpr(
1057-
ExtraArgs->S, RetryExpr.get(), OpLoc, tok::arrow, TempSS,
1057+
ExtraArgs->S, RetryExpr.get(), OpLoc, /*IsArrow=*/true, TempSS,
10581058
TemplateKWLoc, ExtraArgs->Id, ExtraArgs->ObjCImpDecl);
10591059
}
10601060
if (Trap.hasErrorOccurred())
@@ -1768,12 +1768,10 @@ static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
17681768
/// decl; this is an ugly hack around the fact that Objective-C
17691769
/// \@implementations aren't properly put in the context chain
17701770
ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
1771-
SourceLocation OpLoc,
1772-
tok::TokenKind OpKind,
1771+
SourceLocation OpLoc, bool IsArrow,
17731772
CXXScopeSpec &SS,
17741773
SourceLocation TemplateKWLoc,
1775-
UnqualifiedId &Id,
1776-
Decl *ObjCImpDecl) {
1774+
UnqualifiedId &Id, Decl *ObjCImpDecl) {
17771775
if (SS.isSet() && SS.isInvalid())
17781776
return ExprError();
17791777

@@ -1791,8 +1789,6 @@ ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
17911789
DecomposeUnqualifiedId(Id, TemplateArgsBuffer,
17921790
NameInfo, TemplateArgs);
17931791

1794-
bool IsArrow = (OpKind == tok::arrow);
1795-
17961792
if (getLangOpts().HLSL && IsArrow)
17971793
return ExprError(Diag(OpLoc, diag::err_hlsl_operator_unsupported) << 2);
17981794

‎clang/lib/Sema/SemaPseudoObject.cpp

Lines changed: 8 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -1395,10 +1395,10 @@ ExprResult MSPropertyOpBuilder::buildGet() {
13951395
GetterName.setIdentifier(II, RefExpr->getMemberLoc());
13961396
CXXScopeSpec SS;
13971397
SS.Adopt(RefExpr->getQualifierLoc());
1398-
ExprResult GetterExpr =
1399-
S.ActOnMemberAccessExpr(S.getCurScope(), InstanceBase, SourceLocation(),
1400-
RefExpr->isArrow() ? tok::arrow : tok::period, SS,
1401-
SourceLocation(), GetterName, nullptr);
1398+
ExprResult GetterExpr = S.ActOnMemberAccessExpr(
1399+
S.getCurScope(), InstanceBase, /*OpLoc=*/SourceLocation(),
1400+
RefExpr->isArrow(), SS, /*TemplateKWLoc=*/SourceLocation(), GetterName,
1401+
/*ObjCImpDecl=*/nullptr);
14021402
if (GetterExpr.isInvalid()) {
14031403
S.Diag(RefExpr->getMemberLoc(),
14041404
diag::err_cannot_find_suitable_accessor) << 0 /* getter */
@@ -1424,10 +1424,10 @@ ExprResult MSPropertyOpBuilder::buildSet(Expr *op, SourceLocation sl,
14241424
SetterName.setIdentifier(II, RefExpr->getMemberLoc());
14251425
CXXScopeSpec SS;
14261426
SS.Adopt(RefExpr->getQualifierLoc());
1427-
ExprResult SetterExpr =
1428-
S.ActOnMemberAccessExpr(S.getCurScope(), InstanceBase, SourceLocation(),
1429-
RefExpr->isArrow() ? tok::arrow : tok::period, SS,
1430-
SourceLocation(), SetterName, nullptr);
1427+
ExprResult SetterExpr = S.ActOnMemberAccessExpr(
1428+
S.getCurScope(), InstanceBase, /*OpLoc=*/SourceLocation(),
1429+
RefExpr->isArrow(), SS, /*TemplateKWLoc=*/SourceLocation(), SetterName,
1430+
/*ObjCImpDecl=*/nullptr);
14311431
if (SetterExpr.isInvalid()) {
14321432
S.Diag(RefExpr->getMemberLoc(),
14331433
diag::err_cannot_find_suitable_accessor) << 1 /* setter */

‎clang/lib/Sema/SemaTemplate.cpp

Lines changed: 13 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -214,6 +214,7 @@ TemplateNameKind Sema::isTemplateName(Scope *S,
214214
&AssumedTemplate,
215215
/*AllowTypoCorrection=*/!Disambiguation))
216216
return TNK_Non_template;
217+
217218
MemberOfUnknownSpecialization = R.wasNotFoundInCurrentInstantiation();
218219

219220
if (AssumedTemplate != AssumedTemplateKind::None) {
@@ -433,7 +434,6 @@ bool Sema::LookupTemplateName(LookupResult &Found, Scope *S, CXXScopeSpec &SS,
433434
}
434435

435436
bool ObjectTypeSearchedInScope = false;
436-
bool AllowFunctionTemplatesInLookup = true;
437437
if (LookupCtx) {
438438
// Perform "qualified" name lookup into the declaration context we
439439
// computed, which is either the type of the base of a member access
@@ -452,7 +452,14 @@ bool Sema::LookupTemplateName(LookupResult &Found, Scope *S, CXXScopeSpec &SS,
452452
IsDependent |= Found.wasNotFoundInCurrentInstantiation();
453453
}
454454

455-
if (SS.isEmpty() && (ObjectType.isNull() || Found.empty())) {
455+
bool LookupFirstQualifierInScope =
456+
Found.getLookupKind() != LookupMemberName && Found.empty() &&
457+
!ObjectType.isNull() && !IsDependent;
458+
459+
// FIXME: We should still do the lookup if the object expression is dependent,
460+
// but instead of using them we should store them via
461+
// setFirstQualifierFoundInScope and pretend we found nothing.
462+
if (SS.isEmpty() && (ObjectType.isNull() || LookupFirstQualifierInScope)) {
456463
// C++ [basic.lookup.classref]p1:
457464
// In a class member access expression (5.2.5), if the . or -> token is
458465
// immediately followed by an identifier followed by a <, the
@@ -464,14 +471,11 @@ bool Sema::LookupTemplateName(LookupResult &Found, Scope *S, CXXScopeSpec &SS,
464471
// template.
465472
if (S)
466473
LookupName(Found, S);
474+
else if (LookupFirstQualifierInScope && SS.getFirstQualifierFoundInScope())
475+
Found.addDecl(SS.getFirstQualifierFoundInScope());
467476

468-
if (!ObjectType.isNull()) {
469-
// FIXME: We should filter out all non-type templates here, particularly
470-
// variable templates and concepts. But the exclusion of alias templates
471-
// and template template parameters is a wording defect.
472-
AllowFunctionTemplatesInLookup = false;
477+
if (!ObjectType.isNull())
473478
ObjectTypeSearchedInScope = true;
474-
}
475479

476480
IsDependent |= Found.wasNotFoundInCurrentInstantiation();
477481
}
@@ -542,7 +546,7 @@ bool Sema::LookupTemplateName(LookupResult &Found, Scope *S, CXXScopeSpec &SS,
542546

543547
NamedDecl *ExampleLookupResult =
544548
Found.empty() ? nullptr : Found.getRepresentativeDecl();
545-
FilterAcceptableTemplateNames(Found, AllowFunctionTemplatesInLookup);
549+
FilterAcceptableTemplateNames(Found);
546550
if (Found.empty()) {
547551
if (IsDependent) {
548552
Found.setNotFoundInCurrentInstantiation();

‎clang/lib/Sema/TreeTransform.h

Lines changed: 15 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -2894,6 +2894,8 @@ class TreeTransform {
28942894

28952895
CXXScopeSpec SS;
28962896
SS.Adopt(QualifierLoc);
2897+
if (FirstQualifierInScope)
2898+
SS.setFoundFirstQualifierInScope(FirstQualifierInScope);
28972899

28982900
Base = BaseResult.get();
28992901
QualType BaseType = Base->getType();
@@ -3582,6 +3584,9 @@ class TreeTransform {
35823584
CXXScopeSpec SS;
35833585
SS.Adopt(QualifierLoc);
35843586

3587+
if (FirstQualifierInScope)
3588+
SS.setFoundFirstQualifierInScope(FirstQualifierInScope);
3589+
35853590
return SemaRef.BuildMemberReferenceExpr(BaseE, BaseType,
35863591
OperatorLoc, IsArrow,
35873592
SS, TemplateKWLoc,
@@ -3605,6 +3610,9 @@ class TreeTransform {
36053610
CXXScopeSpec SS;
36063611
SS.Adopt(QualifierLoc);
36073612

3613+
if (FirstQualifierInScope)
3614+
SS.setFoundFirstQualifierInScope(FirstQualifierInScope);
3615+
36083616
return SemaRef.BuildMemberReferenceExpr(BaseE, BaseType,
36093617
OperatorLoc, IsArrow,
36103618
SS, TemplateKWLoc,
@@ -4383,6 +4391,8 @@ NestedNameSpecifierLoc TreeTransform<Derived>::TransformNestedNameSpecifierLoc(
43834391
insertNNS(NNS);
43844392

43854393
CXXScopeSpec SS;
4394+
if (FirstQualifierInScope)
4395+
SS.setFoundFirstQualifierInScope(FirstQualifierInScope);
43864396
while (!Qualifiers.empty()) {
43874397
NestedNameSpecifierLoc Q = Qualifiers.pop_back_val();
43884398
NestedNameSpecifier *QNNS = Q.getNestedNameSpecifier();
@@ -5180,6 +5190,9 @@ TypeSourceInfo *TreeTransform<Derived>::TransformTSIInObjectScope(
51805190
TypeLocBuilder TLB;
51815191
QualType Result;
51825192

5193+
if (UnqualLookup)
5194+
SS.setFoundFirstQualifierInScope(UnqualLookup);
5195+
51835196
if (isa<TemplateSpecializationType>(T)) {
51845197
TemplateSpecializationTypeLoc SpecTL =
51855198
TL.castAs<TemplateSpecializationTypeLoc>();
@@ -16173,6 +16186,8 @@ TreeTransform<Derived>::RebuildTemplateName(CXXScopeSpec &SS,
1617316186
UnqualifiedId TemplateName;
1617416187
TemplateName.setIdentifier(&Name, NameLoc);
1617516188
Sema::TemplateTy Template;
16189+
if (FirstQualifierInScope)
16190+
SS.setFoundFirstQualifierInScope(FirstQualifierInScope);
1617616191
getSema().ActOnTemplateName(/*Scope=*/nullptr, SS, TemplateKWLoc,
1617716192
TemplateName, ParsedType::make(ObjectType),
1617816193
/*EnteringContext=*/false, Template,

‎clang/test/CXX/basic/basic.lookup/basic.lookup.classref/p1-cxx11.cpp

Lines changed: 11 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -55,15 +55,21 @@ namespace PR11856 {
5555

5656
template<typename T> T *end(T*);
5757

58-
class X { };
58+
struct X { };
59+
struct Y {
60+
int end;
61+
};
5962
template <typename T>
6063
void Foo2() {
6164
T it1;
62-
if (it1->end < it1->end) {
63-
}
65+
if (it1->end < it1->end) { }
6466

6567
X *x;
66-
if (x->end < 7) { // expected-error{{no member named 'end' in 'PR11856::X'}}
67-
}
68+
if (x->end < 7) { } // expected-error{{expected '>'}}
69+
// expected-note@-1{{to match this '<'}}
70+
// expected-error@-2{{expected unqualified-id}}
71+
72+
Y *y;
73+
if (y->end < 7) { }
6874
}
6975
}

‎clang/test/CXX/basic/basic.lookup/basic.lookup.classref/p1.cpp

Lines changed: 11 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -86,15 +86,21 @@ namespace PR11856 {
8686

8787
template<typename T> T *end(T*);
8888

89-
class X { };
89+
struct X { };
90+
struct Y {
91+
int end;
92+
};
9093
template <typename T>
9194
void Foo2() {
9295
T it1;
93-
if (it1->end < it1->end) {
94-
}
96+
if (it1->end < it1->end) { }
9597

9698
X *x;
97-
if (x->end < 7) { // expected-error{{no member named 'end' in 'PR11856::X'}}
98-
}
99+
if (x->end < 7) { } // expected-error{{expected '>'}}
100+
// expected-note@-1{{to match this '<'}}
101+
// expected-error@-2{{expected unqualified-id}}
102+
103+
Y *y;
104+
if (y->end < 7) { }
99105
}
100106
}

0 commit comments

Comments
 (0)