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-rw-r--r--lib/Sema/SemaCXXScopeSpec.cpp381
1 files changed, 314 insertions, 67 deletions
diff --git a/lib/Sema/SemaCXXScopeSpec.cpp b/lib/Sema/SemaCXXScopeSpec.cpp
index a14bcd5287cd..10c138c7558f 100644
--- a/lib/Sema/SemaCXXScopeSpec.cpp
+++ b/lib/Sema/SemaCXXScopeSpec.cpp
@@ -14,26 +14,89 @@
#include "Sema.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclTemplate.h"
+#include "clang/AST/ExprCXX.h"
#include "clang/AST/NestedNameSpecifier.h"
+#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Parse/DeclSpec.h"
#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/raw_ostream.h"
using namespace clang;
+/// \brief Compute the DeclContext that is associated with the given type.
+///
+/// \param T the type for which we are attempting to find a DeclContext.
+///
+/// \returns the declaration context represented by the type T,
+/// or NULL if the declaration context cannot be computed (e.g., because it is
+/// dependent and not the current instantiation).
+DeclContext *Sema::computeDeclContext(QualType T) {
+ if (const TagType *Tag = T->getAs<TagType>())
+ return Tag->getDecl();
+
+ return 0;
+}
+
/// \brief Compute the DeclContext that is associated with the given
/// scope specifier.
-DeclContext *Sema::computeDeclContext(const CXXScopeSpec &SS) {
+///
+/// \param SS the C++ scope specifier as it appears in the source
+///
+/// \param EnteringContext when true, we will be entering the context of
+/// this scope specifier, so we can retrieve the declaration context of a
+/// class template or class template partial specialization even if it is
+/// not the current instantiation.
+///
+/// \returns the declaration context represented by the scope specifier @p SS,
+/// or NULL if the declaration context cannot be computed (e.g., because it is
+/// dependent and not the current instantiation).
+DeclContext *Sema::computeDeclContext(const CXXScopeSpec &SS,
+ bool EnteringContext) {
if (!SS.isSet() || SS.isInvalid())
return 0;
- NestedNameSpecifier *NNS
+ NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
if (NNS->isDependent()) {
// If this nested-name-specifier refers to the current
// instantiation, return its DeclContext.
if (CXXRecordDecl *Record = getCurrentInstantiationOf(NNS))
return Record;
- else
- return 0;
+
+ if (EnteringContext) {
+ if (const TemplateSpecializationType *SpecType
+ = dyn_cast_or_null<TemplateSpecializationType>(NNS->getAsType())) {
+ // We are entering the context of the nested name specifier, so try to
+ // match the nested name specifier to either a primary class template
+ // or a class template partial specialization.
+ if (ClassTemplateDecl *ClassTemplate
+ = dyn_cast_or_null<ClassTemplateDecl>(
+ SpecType->getTemplateName().getAsTemplateDecl())) {
+ QualType ContextType
+ = Context.getCanonicalType(QualType(SpecType, 0));
+
+ // If the type of the nested name specifier is the same as the
+ // injected class name of the named class template, we're entering
+ // into that class template definition.
+ QualType Injected = ClassTemplate->getInjectedClassNameType(Context);
+ if (Context.hasSameType(Injected, ContextType))
+ return ClassTemplate->getTemplatedDecl();
+
+ // If the type of the nested name specifier is the same as the
+ // type of one of the class template's class template partial
+ // specializations, we're entering into the definition of that
+ // class template partial specialization.
+ if (ClassTemplatePartialSpecializationDecl *PartialSpec
+ = ClassTemplate->findPartialSpecialization(ContextType))
+ return PartialSpec;
+ }
+ } else if (const RecordType *RecordT
+ = dyn_cast_or_null<RecordType>(NNS->getAsType())) {
+ // The nested name specifier refers to a member of a class template.
+ return RecordT->getDecl();
+ }
+ }
+
+ return 0;
}
switch (NNS->getKind()) {
@@ -46,7 +109,7 @@ DeclContext *Sema::computeDeclContext(const CXXScopeSpec &SS) {
case NestedNameSpecifier::TypeSpec:
case NestedNameSpecifier::TypeSpecWithTemplate: {
- const TagType *Tag = NNS->getAsType()->getAsTagType();
+ const TagType *Tag = NNS->getAsType()->getAs<TagType>();
assert(Tag && "Non-tag type in nested-name-specifier");
return Tag->getDecl();
} break;
@@ -63,7 +126,7 @@ bool Sema::isDependentScopeSpecifier(const CXXScopeSpec &SS) {
if (!SS.isSet() || SS.isInvalid())
return false;
- NestedNameSpecifier *NNS
+ NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
return NNS->isDependent();
}
@@ -75,7 +138,7 @@ bool Sema::isUnknownSpecialization(const CXXScopeSpec &SS) {
if (!isDependentScopeSpecifier(SS))
return false;
- NestedNameSpecifier *NNS
+ NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
return getCurrentInstantiationOf(NNS) == 0;
}
@@ -89,6 +152,9 @@ CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) {
assert(getLangOptions().CPlusPlus && "Only callable in C++");
assert(NNS->isDependent() && "Only dependent nested-name-specifier allowed");
+ if (!NNS->getAsType())
+ return 0;
+
QualType T = QualType(NNS->getAsType(), 0);
// If the nested name specifier does not refer to a type, then it
// does not refer to the current instantiation.
@@ -108,7 +174,7 @@ CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) {
if (!Record)
continue;
- // If this record type is not dependent,
+ // If this record type is not dependent,
if (!Record->isDependentType())
return 0;
@@ -126,27 +192,29 @@ CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) {
// enclosed in <>,
// -- in the definition of a nested class of a class template,
// the name of the nested class referenced as a member of
- // the current instantiation, or
+ // the current instantiation, or
// -- in the definition of a partial specialization, the name
// of the class template followed by the template argument
// list of the partial specialization enclosed in <>. If
// the nth template parameter is a parameter pack, the nth
// template argument is a pack expansion (14.6.3) whose
- // pattern is the name of the parameter pack. (FIXME)
+ // pattern is the name of the parameter pack.
+ // (FIXME: parameter packs)
//
// All of these options come down to having the
// nested-name-specifier type that is equivalent to the
// injected-class-name of one of the types that is currently in
// our context.
- if (Context.getTypeDeclType(Record) == T)
+ if (Context.getCanonicalType(Context.getTypeDeclType(Record)) == T)
return Record;
-
+
if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) {
- QualType InjectedClassName
+ QualType InjectedClassName
= Template->getInjectedClassNameType(Context);
if (T == Context.getCanonicalType(InjectedClassName))
return Template->getTemplatedDecl();
}
+ // FIXME: check for class template partial specializations
}
return 0;
@@ -164,20 +232,20 @@ CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) {
bool Sema::RequireCompleteDeclContext(const CXXScopeSpec &SS) {
if (!SS.isSet() || SS.isInvalid())
return false;
-
- DeclContext *DC = computeDeclContext(SS);
+
+ DeclContext *DC = computeDeclContext(SS, true);
if (TagDecl *Tag = dyn_cast<TagDecl>(DC)) {
// If we're currently defining this type, then lookup into the
// type is okay: don't complain that it isn't complete yet.
- const TagType *TagT = Context.getTypeDeclType(Tag)->getAsTagType();
+ const TagType *TagT = Context.getTypeDeclType(Tag)->getAs<TagType>();
if (TagT->isBeingDefined())
return false;
// The type must be complete.
return RequireCompleteType(SS.getRange().getBegin(),
Context.getTypeDeclType(Tag),
- diag::err_incomplete_nested_name_spec,
- SS.getRange());
+ PDiag(diag::err_incomplete_nested_name_spec)
+ << SS.getRange());
}
return false;
@@ -190,72 +258,222 @@ Sema::CXXScopeTy *Sema::ActOnCXXGlobalScopeSpecifier(Scope *S,
return NestedNameSpecifier::GlobalSpecifier(Context);
}
-/// ActOnCXXNestedNameSpecifier - Called during parsing of a
-/// nested-name-specifier. e.g. for "foo::bar::" we parsed "foo::" and now
-/// we want to resolve "bar::". 'SS' is empty or the previously parsed
-/// nested-name part ("foo::"), 'IdLoc' is the source location of 'bar',
-/// 'CCLoc' is the location of '::' and 'II' is the identifier for 'bar'.
-/// Returns a CXXScopeTy* object representing the C++ scope.
-Sema::CXXScopeTy *Sema::ActOnCXXNestedNameSpecifier(Scope *S,
+/// \brief Determines whether the given declaration is an valid acceptable
+/// result for name lookup of a nested-name-specifier.
+bool Sema::isAcceptableNestedNameSpecifier(NamedDecl *SD) {
+ if (!SD)
+ return false;
+
+ // Namespace and namespace aliases are fine.
+ if (isa<NamespaceDecl>(SD) || isa<NamespaceAliasDecl>(SD))
+ return true;
+
+ if (!isa<TypeDecl>(SD))
+ return false;
+
+ // Determine whether we have a class (or, in C++0x, an enum) or
+ // a typedef thereof. If so, build the nested-name-specifier.
+ QualType T = Context.getTypeDeclType(cast<TypeDecl>(SD));
+ if (T->isDependentType())
+ return true;
+ else if (TypedefDecl *TD = dyn_cast<TypedefDecl>(SD)) {
+ if (TD->getUnderlyingType()->isRecordType() ||
+ (Context.getLangOptions().CPlusPlus0x &&
+ TD->getUnderlyingType()->isEnumeralType()))
+ return true;
+ } else if (isa<RecordDecl>(SD) ||
+ (Context.getLangOptions().CPlusPlus0x && isa<EnumDecl>(SD)))
+ return true;
+
+ return false;
+}
+
+/// \brief If the given nested-name-specifier begins with a bare identifier
+/// (e.g., Base::), perform name lookup for that identifier as a
+/// nested-name-specifier within the given scope, and return the result of that
+/// name lookup.
+NamedDecl *Sema::FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS) {
+ if (!S || !NNS)
+ return 0;
+
+ while (NNS->getPrefix())
+ NNS = NNS->getPrefix();
+
+ if (NNS->getKind() != NestedNameSpecifier::Identifier)
+ return 0;
+
+ LookupResult Found;
+ LookupName(Found, S, NNS->getAsIdentifier(), LookupNestedNameSpecifierName);
+ assert(!Found.isAmbiguous() && "Cannot handle ambiguities here yet");
+
+ NamedDecl *Result = Found.getAsSingleDecl(Context);
+ if (isAcceptableNestedNameSpecifier(Result))
+ return Result;
+
+ return 0;
+}
+
+/// \brief Build a new nested-name-specifier for "identifier::", as described
+/// by ActOnCXXNestedNameSpecifier.
+///
+/// This routine differs only slightly from ActOnCXXNestedNameSpecifier, in
+/// that it contains an extra parameter \p ScopeLookupResult, which provides
+/// the result of name lookup within the scope of the nested-name-specifier
+/// that was computed at template definitino time.
+Sema::CXXScopeTy *Sema::BuildCXXNestedNameSpecifier(Scope *S,
const CXXScopeSpec &SS,
SourceLocation IdLoc,
SourceLocation CCLoc,
- IdentifierInfo &II) {
- NestedNameSpecifier *Prefix
+ IdentifierInfo &II,
+ QualType ObjectType,
+ NamedDecl *ScopeLookupResult,
+ bool EnteringContext) {
+ NestedNameSpecifier *Prefix
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
- // If the prefix already refers to an unknown specialization, there
- // is no name lookup to perform. Just build the resulting
- // nested-name-specifier.
- if (Prefix && isUnknownSpecialization(SS))
+ // Determine where to perform name lookup
+ DeclContext *LookupCtx = 0;
+ bool isDependent = false;
+ if (!ObjectType.isNull()) {
+ // This nested-name-specifier occurs in a member access expression, e.g.,
+ // x->B::f, and we are looking into the type of the object.
+ assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
+ LookupCtx = computeDeclContext(ObjectType);
+ isDependent = ObjectType->isDependentType();
+ } else if (SS.isSet()) {
+ // This nested-name-specifier occurs after another nested-name-specifier,
+ // so long into the context associated with the prior nested-name-specifier.
+ LookupCtx = computeDeclContext(SS, EnteringContext);
+ isDependent = isDependentScopeSpecifier(SS);
+ }
+
+ LookupResult Found;
+ bool ObjectTypeSearchedInScope = false;
+ if (LookupCtx) {
+ // Perform "qualified" name lookup into the declaration context we
+ // computed, which is either the type of the base of a member access
+ // expression or the declaration context associated with a prior
+ // nested-name-specifier.
+
+ // The declaration context must be complete.
+ if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(SS))
+ return 0;
+
+ LookupQualifiedName(Found, LookupCtx, &II, LookupNestedNameSpecifierName,
+ false);
+
+ if (!ObjectType.isNull() && Found.getKind() == LookupResult::NotFound) {
+ // C++ [basic.lookup.classref]p4:
+ // If the id-expression in a class member access is a qualified-id of
+ // the form
+ //
+ // class-name-or-namespace-name::...
+ //
+ // the class-name-or-namespace-name following the . or -> operator is
+ // looked up both in the context of the entire postfix-expression and in
+ // the scope of the class of the object expression. If the name is found
+ // only in the scope of the class of the object expression, the name
+ // shall refer to a class-name. If the name is found only in the
+ // context of the entire postfix-expression, the name shall refer to a
+ // class-name or namespace-name. [...]
+ //
+ // Qualified name lookup into a class will not find a namespace-name,
+ // so we do not need to diagnoste that case specifically. However,
+ // this qualified name lookup may find nothing. In that case, perform
+ // unqualified name lookup in the given scope (if available) or
+ // reconstruct the result from when name lookup was performed at template
+ // definition time.
+ if (S)
+ LookupName(Found, S, &II, LookupNestedNameSpecifierName);
+ else if (ScopeLookupResult)
+ Found.addDecl(ScopeLookupResult);
+
+ ObjectTypeSearchedInScope = true;
+ }
+ } else if (isDependent) {
+ // We were not able to compute the declaration context for a dependent
+ // base object type or prior nested-name-specifier, so this
+ // nested-name-specifier refers to an unknown specialization. Just build
+ // a dependent nested-name-specifier.
+ if (!Prefix)
+ return NestedNameSpecifier::Create(Context, &II);
+
return NestedNameSpecifier::Create(Context, Prefix, &II);
+ } else {
+ // Perform unqualified name lookup in the current scope.
+ LookupName(Found, S, &II, LookupNestedNameSpecifierName);
+ }
- NamedDecl *SD = LookupParsedName(S, &SS, &II, LookupNestedNameSpecifierName);
+ // FIXME: Deal with ambiguities cleanly.
+ NamedDecl *SD = Found.getAsSingleDecl(Context);
+ if (isAcceptableNestedNameSpecifier(SD)) {
+ if (!ObjectType.isNull() && !ObjectTypeSearchedInScope) {
+ // C++ [basic.lookup.classref]p4:
+ // [...] If the name is found in both contexts, the
+ // class-name-or-namespace-name shall refer to the same entity.
+ //
+ // We already found the name in the scope of the object. Now, look
+ // into the current scope (the scope of the postfix-expression) to
+ // see if we can find the same name there. As above, if there is no
+ // scope, reconstruct the result from the template instantiation itself.
+ NamedDecl *OuterDecl;
+ if (S) {
+ LookupResult FoundOuter;
+ LookupName(FoundOuter, S, &II, LookupNestedNameSpecifierName);
+ // FIXME: Handle ambiguities!
+ OuterDecl = FoundOuter.getAsSingleDecl(Context);
+ } else
+ OuterDecl = ScopeLookupResult;
+
+ if (isAcceptableNestedNameSpecifier(OuterDecl) &&
+ OuterDecl->getCanonicalDecl() != SD->getCanonicalDecl() &&
+ (!isa<TypeDecl>(OuterDecl) || !isa<TypeDecl>(SD) ||
+ !Context.hasSameType(
+ Context.getTypeDeclType(cast<TypeDecl>(OuterDecl)),
+ Context.getTypeDeclType(cast<TypeDecl>(SD))))) {
+ Diag(IdLoc, diag::err_nested_name_member_ref_lookup_ambiguous)
+ << &II;
+ Diag(SD->getLocation(), diag::note_ambig_member_ref_object_type)
+ << ObjectType;
+ Diag(OuterDecl->getLocation(), diag::note_ambig_member_ref_scope);
+
+ // Fall through so that we'll pick the name we found in the object type,
+ // since that's probably what the user wanted anyway.
+ }
+ }
- if (SD) {
if (NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(SD))
return NestedNameSpecifier::Create(Context, Prefix, Namespace);
- if (TypeDecl *Type = dyn_cast<TypeDecl>(SD)) {
- // Determine whether we have a class (or, in C++0x, an enum) or
- // a typedef thereof. If so, build the nested-name-specifier.
- QualType T = Context.getTypeDeclType(Type);
- bool AcceptableType = false;
- if (T->isDependentType())
- AcceptableType = true;
- else if (TypedefDecl *TD = dyn_cast<TypedefDecl>(SD)) {
- if (TD->getUnderlyingType()->isRecordType() ||
- (getLangOptions().CPlusPlus0x &&
- TD->getUnderlyingType()->isEnumeralType()))
- AcceptableType = true;
- } else if (isa<RecordDecl>(Type) ||
- (getLangOptions().CPlusPlus0x && isa<EnumDecl>(Type)))
- AcceptableType = true;
-
- if (AcceptableType)
- return NestedNameSpecifier::Create(Context, Prefix, false,
- T.getTypePtr());
- }
-
+ // FIXME: It would be nice to maintain the namespace alias name, then
+ // see through that alias when resolving the nested-name-specifier down to
+ // a declaration context.
if (NamespaceAliasDecl *Alias = dyn_cast<NamespaceAliasDecl>(SD))
return NestedNameSpecifier::Create(Context, Prefix,
+
Alias->getNamespace());
- // Fall through to produce an error: we found something that isn't
- // a class or a namespace.
+ QualType T = Context.getTypeDeclType(cast<TypeDecl>(SD));
+ return NestedNameSpecifier::Create(Context, Prefix, false,
+ T.getTypePtr());
}
// If we didn't find anything during our lookup, try again with
// ordinary name lookup, which can help us produce better error
// messages.
- if (!SD)
- SD = LookupParsedName(S, &SS, &II, LookupOrdinaryName);
+ if (!SD) {
+ Found.clear();
+ LookupName(Found, S, &II, LookupOrdinaryName);
+ SD = Found.getAsSingleDecl(Context);
+ }
+
unsigned DiagID;
if (SD)
DiagID = diag::err_expected_class_or_namespace;
- else if (SS.isSet())
- DiagID = diag::err_typecheck_no_member;
- else
+ else if (SS.isSet()) {
+ Diag(IdLoc, diag::err_no_member) << &II << LookupCtx << SS.getRange();
+ return 0;
+ } else
DiagID = diag::err_undeclared_var_use;
if (SS.isSet())
@@ -266,14 +484,32 @@ Sema::CXXScopeTy *Sema::ActOnCXXNestedNameSpecifier(Scope *S,
return 0;
}
+/// ActOnCXXNestedNameSpecifier - Called during parsing of a
+/// nested-name-specifier. e.g. for "foo::bar::" we parsed "foo::" and now
+/// we want to resolve "bar::". 'SS' is empty or the previously parsed
+/// nested-name part ("foo::"), 'IdLoc' is the source location of 'bar',
+/// 'CCLoc' is the location of '::' and 'II' is the identifier for 'bar'.
+/// Returns a CXXScopeTy* object representing the C++ scope.
+Sema::CXXScopeTy *Sema::ActOnCXXNestedNameSpecifier(Scope *S,
+ const CXXScopeSpec &SS,
+ SourceLocation IdLoc,
+ SourceLocation CCLoc,
+ IdentifierInfo &II,
+ TypeTy *ObjectTypePtr,
+ bool EnteringContext) {
+ return BuildCXXNestedNameSpecifier(S, SS, IdLoc, CCLoc, II,
+ QualType::getFromOpaquePtr(ObjectTypePtr),
+ /*ScopeLookupResult=*/0, EnteringContext);
+}
+
Sema::CXXScopeTy *Sema::ActOnCXXNestedNameSpecifier(Scope *S,
const CXXScopeSpec &SS,
TypeTy *Ty,
SourceRange TypeRange,
SourceLocation CCLoc) {
- NestedNameSpecifier *Prefix
+ NestedNameSpecifier *Prefix
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
- QualType T = QualType::getFromOpaquePtr(Ty);
+ QualType T = GetTypeFromParser(Ty);
return NestedNameSpecifier::Create(Context, Prefix, /*FIXME:*/false,
T.getTypePtr());
}
@@ -284,9 +520,18 @@ Sema::CXXScopeTy *Sema::ActOnCXXNestedNameSpecifier(Scope *S,
/// looked up in the declarator-id's scope, until the declarator is parsed and
/// ActOnCXXExitDeclaratorScope is called.
/// The 'SS' should be a non-empty valid CXXScopeSpec.
-void Sema::ActOnCXXEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
+bool Sema::ActOnCXXEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
assert(SS.isSet() && "Parser passed invalid CXXScopeSpec.");
- EnterDeclaratorContext(S, computeDeclContext(SS));
+ if (DeclContext *DC = computeDeclContext(SS, true)) {
+ // Before we enter a declarator's context, we need to make sure that
+ // it is a complete declaration context.
+ if (!DC->isDependentContext() && RequireCompleteDeclContext(SS))
+ return true;
+
+ EnterDeclaratorContext(S, DC);
+ }
+
+ return false;
}
/// ActOnCXXExitDeclaratorScope - Called when a declarator that previously
@@ -296,6 +541,8 @@ void Sema::ActOnCXXEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
/// defining scope.
void Sema::ActOnCXXExitDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
assert(SS.isSet() && "Parser passed invalid CXXScopeSpec.");
- assert(S->getEntity() == computeDeclContext(SS) && "Context imbalance!");
- ExitDeclaratorContext(S);
+ if (SS.isInvalid())
+ return;
+ if (computeDeclContext(SS, true))
+ ExitDeclaratorContext(S);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-18 14:11:04 +0000