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llvm-project/clang/lib/Sema/SemaTemplate.cpp

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//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//===----------------------------------------------------------------------===/
//
// This file implements semantic analysis for C++ templates.
//===----------------------------------------------------------------------===/
#include "Sema.h"
#include "TreeTransform.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/Parse/DeclSpec.h"
#include "clang/Basic/LangOptions.h"
#include "llvm/Support/Compiler.h"
using namespace clang;
/// \brief Determine whether the declaration found is acceptable as the name
/// of a template and, if so, return that template declaration. Otherwise,
/// returns NULL.
static NamedDecl *isAcceptableTemplateName(ASTContext &Context, NamedDecl *D) {
if (!D)
return 0;
if (isa<TemplateDecl>(D))
return D;
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
// C++ [temp.local]p1:
// Like normal (non-template) classes, class templates have an
// injected-class-name (Clause 9). The injected-class-name
// can be used with or without a template-argument-list. When
// it is used without a template-argument-list, it is
// equivalent to the injected-class-name followed by the
// template-parameters of the class template enclosed in
// <>. When it is used with a template-argument-list, it
// refers to the specified class template specialization,
// which could be the current specialization or another
// specialization.
if (Record->isInjectedClassName()) {
Record = cast<CXXRecordDecl>(Record->getCanonicalDecl());
if (Record->getDescribedClassTemplate())
return Record->getDescribedClassTemplate();
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(Record))
return Spec->getSpecializedTemplate();
}
return 0;
}
OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D);
if (!Ovl)
return 0;
for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(),
FEnd = Ovl->function_end();
F != FEnd; ++F) {
if (FunctionTemplateDecl *FuncTmpl = dyn_cast<FunctionTemplateDecl>(*F)) {
// We've found a function template. Determine whether there are
// any other function templates we need to bundle together in an
// OverloadedFunctionDecl
for (++F; F != FEnd; ++F) {
if (isa<FunctionTemplateDecl>(*F))
break;
}
if (F != FEnd) {
// Build an overloaded function decl containing only the
// function templates in Ovl.
OverloadedFunctionDecl *OvlTemplate
= OverloadedFunctionDecl::Create(Context,
Ovl->getDeclContext(),
Ovl->getDeclName());
OvlTemplate->addOverload(FuncTmpl);
OvlTemplate->addOverload(*F);
for (++F; F != FEnd; ++F) {
if (isa<FunctionTemplateDecl>(*F))
OvlTemplate->addOverload(*F);
}
return OvlTemplate;
}
return FuncTmpl;
}
}
return 0;
}
TemplateNameKind Sema::isTemplateName(Scope *S,
const IdentifierInfo &II,
SourceLocation IdLoc,
const CXXScopeSpec *SS,
TypeTy *ObjectTypePtr,
bool EnteringContext,
TemplateTy &TemplateResult) {
// Determine where to perform name lookup
DeclContext *LookupCtx = 0;
bool isDependent = false;
if (ObjectTypePtr) {
// 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 || !SS->isSet()) &&
"ObjectType and scope specifier cannot coexist");
QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr);
LookupCtx = computeDeclContext(ObjectType);
isDependent = ObjectType->isDependentType();
} else if (SS && 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 TNK_Non_template;
Found = LookupQualifiedName(LookupCtx, &II, LookupOrdinaryName);
if (ObjectTypePtr && Found.getKind() == LookupResult::NotFound) {
// C++ [basic.lookup.classref]p1:
// In a class member access expression (5.2.5), if the . or -> token is
// immediately followed by an identifier followed by a <, the
// identifier must be looked up to determine whether the < is the
// beginning of a template argument list (14.2) or a less-than operator.
// The identifier is first looked up in the class of the object
// expression. If the identifier is not found, it is then looked up in
// the context of the entire postfix-expression and shall name a class
// or function template.
//
// FIXME: When we're instantiating a template, do we actually have to
// look in the scope of the template? Seems fishy...
Found = LookupName(S, &II, LookupOrdinaryName);
ObjectTypeSearchedInScope = true;
}
} else if (isDependent) {
// We cannot look into a dependent object type or
return TNK_Non_template;
} else {
// Perform unqualified name lookup in the current scope.
Found = LookupName(S, &II, LookupOrdinaryName);
}
// FIXME: Cope with ambiguous name-lookup results.
assert(!Found.isAmbiguous() &&
"Cannot handle template name-lookup ambiguities");
NamedDecl *Template = isAcceptableTemplateName(Context, Found);
if (!Template)
return TNK_Non_template;
if (ObjectTypePtr && !ObjectTypeSearchedInScope) {
// C++ [basic.lookup.classref]p1:
// [...] If the lookup in the class of the object expression finds a
// template, the name is also looked up in the context of the entire
// postfix-expression and [...]
//
LookupResult FoundOuter = LookupName(S, &II, LookupOrdinaryName);
// FIXME: Handle ambiguities in this lookup better
NamedDecl *OuterTemplate = isAcceptableTemplateName(Context, FoundOuter);
if (!OuterTemplate) {
// - if the name is not found, the name found in the class of the
// object expression is used, otherwise
} else if (!isa<ClassTemplateDecl>(OuterTemplate)) {
// - if the name is found in the context of the entire
// postfix-expression and does not name a class template, the name
// found in the class of the object expression is used, otherwise
} else {
// - if the name found is a class template, it must refer to the same
// entity as the one found in the class of the object expression,
// otherwise the program is ill-formed.
if (OuterTemplate->getCanonicalDecl() != Template->getCanonicalDecl()) {
Diag(IdLoc, diag::err_nested_name_member_ref_lookup_ambiguous)
<< &II;
Diag(Template->getLocation(), diag::note_ambig_member_ref_object_type)
<< QualType::getFromOpaquePtr(ObjectTypePtr);
Diag(OuterTemplate->getLocation(), diag::note_ambig_member_ref_scope);
// Recover by taking the template that we found in the object
// expression's type.
}
}
}
if (SS && SS->isSet() && !SS->isInvalid()) {
NestedNameSpecifier *Qualifier
= static_cast<NestedNameSpecifier *>(SS->getScopeRep());
if (OverloadedFunctionDecl *Ovl
= dyn_cast<OverloadedFunctionDecl>(Template))
TemplateResult
= TemplateTy::make(Context.getQualifiedTemplateName(Qualifier, false,
Ovl));
else
TemplateResult
= TemplateTy::make(Context.getQualifiedTemplateName(Qualifier, false,
cast<TemplateDecl>(Template)));
} else if (OverloadedFunctionDecl *Ovl
= dyn_cast<OverloadedFunctionDecl>(Template)) {
TemplateResult = TemplateTy::make(TemplateName(Ovl));
} else {
TemplateResult = TemplateTy::make(
TemplateName(cast<TemplateDecl>(Template)));
}
if (isa<ClassTemplateDecl>(Template) ||
isa<TemplateTemplateParmDecl>(Template))
return TNK_Type_template;
assert((isa<FunctionTemplateDecl>(Template) ||
isa<OverloadedFunctionDecl>(Template)) &&
"Unhandled template kind in Sema::isTemplateName");
return TNK_Function_template;
}
/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
/// that the template parameter 'PrevDecl' is being shadowed by a new
/// declaration at location Loc. Returns true to indicate that this is
/// an error, and false otherwise.
bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
// Microsoft Visual C++ permits template parameters to be shadowed.
if (getLangOptions().Microsoft)
return false;
// C++ [temp.local]p4:
// A template-parameter shall not be redeclared within its
// scope (including nested scopes).
Diag(Loc, diag::err_template_param_shadow)
<< cast<NamedDecl>(PrevDecl)->getDeclName();
Diag(PrevDecl->getLocation(), diag::note_template_param_here);
return true;
}
/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
/// the parameter D to reference the templated declaration and return a pointer
/// to the template declaration. Otherwise, do nothing to D and return null.
TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) {
if (TemplateDecl *Temp = dyn_cast<TemplateDecl>(D.getAs<Decl>())) {
D = DeclPtrTy::make(Temp->getTemplatedDecl());
return Temp;
}
return 0;
}
/// ActOnTypeParameter - Called when a C++ template type parameter
/// (e.g., "typename T") has been parsed. Typename specifies whether
/// the keyword "typename" was used to declare the type parameter
/// (otherwise, "class" was used), and KeyLoc is the location of the
/// "class" or "typename" keyword. ParamName is the name of the
/// parameter (NULL indicates an unnamed template parameter) and
/// ParamName is the location of the parameter name (if any).
/// If the type parameter has a default argument, it will be added
/// later via ActOnTypeParameterDefault.
Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
SourceLocation EllipsisLoc,
SourceLocation KeyLoc,
IdentifierInfo *ParamName,
SourceLocation ParamNameLoc,
unsigned Depth, unsigned Position) {
assert(S->isTemplateParamScope() &&
"Template type parameter not in template parameter scope!");
bool Invalid = false;
if (ParamName) {
NamedDecl *PrevDecl = LookupName(S, ParamName, LookupTagName);
if (PrevDecl && PrevDecl->isTemplateParameter())
Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
PrevDecl);
}
SourceLocation Loc = ParamNameLoc;
if (!ParamName)
Loc = KeyLoc;
TemplateTypeParmDecl *Param
= TemplateTypeParmDecl::Create(Context, CurContext, Loc,
Depth, Position, ParamName, Typename,
Ellipsis);
if (Invalid)
Param->setInvalidDecl();
if (ParamName) {
// Add the template parameter into the current scope.
S->AddDecl(DeclPtrTy::make(Param));
IdResolver.AddDecl(Param);
}
return DeclPtrTy::make(Param);
}
/// ActOnTypeParameterDefault - Adds a default argument (the type
/// Default) to the given template type parameter (TypeParam).
void Sema::ActOnTypeParameterDefault(DeclPtrTy TypeParam,
SourceLocation EqualLoc,
SourceLocation DefaultLoc,
TypeTy *DefaultT) {
TemplateTypeParmDecl *Parm
= cast<TemplateTypeParmDecl>(TypeParam.getAs<Decl>());
// FIXME: Preserve type source info.
QualType Default = GetTypeFromParser(DefaultT);
// C++0x [temp.param]p9:
// A default template-argument may be specified for any kind of
// template-parameter that is not a template parameter pack.
if (Parm->isParameterPack()) {
Diag(DefaultLoc, diag::err_template_param_pack_default_arg);
return;
}
// C++ [temp.param]p14:
// A template-parameter shall not be used in its own default argument.
// FIXME: Implement this check! Needs a recursive walk over the types.
// Check the template argument itself.
if (CheckTemplateArgument(Parm, Default, DefaultLoc)) {
Parm->setInvalidDecl();
return;
}
Parm->setDefaultArgument(Default, DefaultLoc, false);
}
/// \brief Check that the type of a non-type template parameter is
/// well-formed.
///
/// \returns the (possibly-promoted) parameter type if valid;
/// otherwise, produces a diagnostic and returns a NULL type.
QualType
Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
// C++ [temp.param]p4:
//
// A non-type template-parameter shall have one of the following
// (optionally cv-qualified) types:
//
// -- integral or enumeration type,
if (T->isIntegralType() || T->isEnumeralType() ||
// -- pointer to object or pointer to function,
(T->isPointerType() &&
(T->getAs<PointerType>()->getPointeeType()->isObjectType() ||
T->getAs<PointerType>()->getPointeeType()->isFunctionType())) ||
// -- reference to object or reference to function,
T->isReferenceType() ||
// -- pointer to member.
T->isMemberPointerType() ||
// If T is a dependent type, we can't do the check now, so we
// assume that it is well-formed.
T->isDependentType())
return T;
// C++ [temp.param]p8:
//
// A non-type template-parameter of type "array of T" or
// "function returning T" is adjusted to be of type "pointer to
// T" or "pointer to function returning T", respectively.
else if (T->isArrayType())
// FIXME: Keep the type prior to promotion?
return Context.getArrayDecayedType(T);
else if (T->isFunctionType())
// FIXME: Keep the type prior to promotion?
return Context.getPointerType(T);
Diag(Loc, diag::err_template_nontype_parm_bad_type)
<< T;
return QualType();
}
/// ActOnNonTypeTemplateParameter - Called when a C++ non-type
/// template parameter (e.g., "int Size" in "template<int Size>
/// class Array") has been parsed. S is the current scope and D is
/// the parsed declarator.
Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
unsigned Depth,
unsigned Position) {
DeclaratorInfo *DInfo = 0;
QualType T = GetTypeForDeclarator(D, S, &DInfo);
assert(S->isTemplateParamScope() &&
"Non-type template parameter not in template parameter scope!");
bool Invalid = false;
IdentifierInfo *ParamName = D.getIdentifier();
if (ParamName) {
NamedDecl *PrevDecl = LookupName(S, ParamName, LookupTagName);
if (PrevDecl && PrevDecl->isTemplateParameter())
Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
PrevDecl);
}
T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
if (T.isNull()) {
T = Context.IntTy; // Recover with an 'int' type.
Invalid = true;
}
NonTypeTemplateParmDecl *Param
= NonTypeTemplateParmDecl::Create(Context, CurContext, D.getIdentifierLoc(),
Depth, Position, ParamName, T, DInfo);
if (Invalid)
Param->setInvalidDecl();
if (D.getIdentifier()) {
// Add the template parameter into the current scope.
S->AddDecl(DeclPtrTy::make(Param));
IdResolver.AddDecl(Param);
}
return DeclPtrTy::make(Param);
}
/// \brief Adds a default argument to the given non-type template
/// parameter.
void Sema::ActOnNonTypeTemplateParameterDefault(DeclPtrTy TemplateParamD,
SourceLocation EqualLoc,
ExprArg DefaultE) {
NonTypeTemplateParmDecl *TemplateParm
= cast<NonTypeTemplateParmDecl>(TemplateParamD.getAs<Decl>());
Expr *Default = static_cast<Expr *>(DefaultE.get());
// C++ [temp.param]p14:
// A template-parameter shall not be used in its own default argument.
// FIXME: Implement this check! Needs a recursive walk over the types.
// Check the well-formedness of the default template argument.
TemplateArgument Converted;
if (CheckTemplateArgument(TemplateParm, TemplateParm->getType(), Default,
Converted)) {
TemplateParm->setInvalidDecl();
return;
}
TemplateParm->setDefaultArgument(DefaultE.takeAs<Expr>());
}
/// ActOnTemplateTemplateParameter - Called when a C++ template template
/// parameter (e.g. T in template <template <typename> class T> class array)
/// has been parsed. S is the current scope.
Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S,
SourceLocation TmpLoc,
TemplateParamsTy *Params,
IdentifierInfo *Name,
SourceLocation NameLoc,
unsigned Depth,
unsigned Position)
{
assert(S->isTemplateParamScope() &&
"Template template parameter not in template parameter scope!");
// Construct the parameter object.
TemplateTemplateParmDecl *Param =
TemplateTemplateParmDecl::Create(Context, CurContext, TmpLoc, Depth,
Position, Name,
(TemplateParameterList*)Params);
// Make sure the parameter is valid.
// FIXME: Decl object is not currently invalidated anywhere so this doesn't
// do anything yet. However, if the template parameter list or (eventual)
// default value is ever invalidated, that will propagate here.
bool Invalid = false;
if (Invalid) {
Param->setInvalidDecl();
}
// If the tt-param has a name, then link the identifier into the scope
// and lookup mechanisms.
if (Name) {
S->AddDecl(DeclPtrTy::make(Param));
IdResolver.AddDecl(Param);
}
return DeclPtrTy::make(Param);
}
/// \brief Adds a default argument to the given template template
/// parameter.
void Sema::ActOnTemplateTemplateParameterDefault(DeclPtrTy TemplateParamD,
SourceLocation EqualLoc,
ExprArg DefaultE) {
TemplateTemplateParmDecl *TemplateParm
= cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>());
// Since a template-template parameter's default argument is an
// id-expression, it must be a DeclRefExpr.
DeclRefExpr *Default
= cast<DeclRefExpr>(static_cast<Expr *>(DefaultE.get()));
// C++ [temp.param]p14:
// A template-parameter shall not be used in its own default argument.
// FIXME: Implement this check! Needs a recursive walk over the types.
// Check the well-formedness of the template argument.
if (!isa<TemplateDecl>(Default->getDecl())) {
Diag(Default->getSourceRange().getBegin(),
diag::err_template_arg_must_be_template)
<< Default->getSourceRange();
TemplateParm->setInvalidDecl();
return;
}
if (CheckTemplateArgument(TemplateParm, Default)) {
TemplateParm->setInvalidDecl();
return;
}
DefaultE.release();
TemplateParm->setDefaultArgument(Default);
}
/// ActOnTemplateParameterList - Builds a TemplateParameterList that
/// contains the template parameters in Params/NumParams.
Sema::TemplateParamsTy *
Sema::ActOnTemplateParameterList(unsigned Depth,
SourceLocation ExportLoc,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
DeclPtrTy *Params, unsigned NumParams,
SourceLocation RAngleLoc) {
if (ExportLoc.isValid())
Diag(ExportLoc, diag::note_template_export_unsupported);
return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
(Decl**)Params, NumParams, RAngleLoc);
}
Sema::DeclResult
Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
SourceLocation KWLoc, const CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
AttributeList *Attr,
TemplateParameterList *TemplateParams,
AccessSpecifier AS) {
assert(TemplateParams && TemplateParams->size() > 0 &&
"No template parameters");
assert(TUK != TUK_Reference && "Can only declare or define class templates");
bool Invalid = false;
// Check that we can declare a template here.
if (CheckTemplateDeclScope(S, TemplateParams))
return true;
TagDecl::TagKind Kind;
switch (TagSpec) {
default: assert(0 && "Unknown tag type!");
case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break;
case DeclSpec::TST_union: Kind = TagDecl::TK_union; break;
case DeclSpec::TST_class: Kind = TagDecl::TK_class; break;
}
// There is no such thing as an unnamed class template.
if (!Name) {
Diag(KWLoc, diag::err_template_unnamed_class);
return true;
}
// Find any previous declaration with this name.
DeclContext *SemanticContext;
LookupResult Previous;
if (SS.isNotEmpty() && !SS.isInvalid()) {
SemanticContext = computeDeclContext(SS, true);
if (!SemanticContext) {
// FIXME: Produce a reasonable diagnostic here
return true;
}
Previous = LookupQualifiedName(SemanticContext, Name, LookupOrdinaryName,
true);
} else {
SemanticContext = CurContext;
Previous = LookupName(S, Name, LookupOrdinaryName, true);
}
assert(!Previous.isAmbiguous() && "Ambiguity in class template redecl?");
NamedDecl *PrevDecl = 0;
if (Previous.begin() != Previous.end())
PrevDecl = *Previous.begin();
if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S))
PrevDecl = 0;
// If there is a previous declaration with the same name, check
// whether this is a valid redeclaration.
ClassTemplateDecl *PrevClassTemplate
= dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
if (PrevClassTemplate) {
// Ensure that the template parameter lists are compatible.
if (!TemplateParameterListsAreEqual(TemplateParams,
PrevClassTemplate->getTemplateParameters(),
/*Complain=*/true))
return true;
// C++ [temp.class]p4:
// In a redeclaration, partial specialization, explicit
// specialization or explicit instantiation of a class template,
// the class-key shall agree in kind with the original class
// template declaration (7.1.5.3).
RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) {
Diag(KWLoc, diag::err_use_with_wrong_tag)
<< Name
<< CodeModificationHint::CreateReplacement(KWLoc,
PrevRecordDecl->getKindName());
Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
Kind = PrevRecordDecl->getTagKind();
}
// Check for redefinition of this class template.
if (TUK == TUK_Definition) {
if (TagDecl *Def = PrevRecordDecl->getDefinition(Context)) {
Diag(NameLoc, diag::err_redefinition) << Name;
Diag(Def->getLocation(), diag::note_previous_definition);
// FIXME: Would it make sense to try to "forget" the previous
// definition, as part of error recovery?
return true;
}
}
} else if (PrevDecl && PrevDecl->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
// Just pretend that we didn't see the previous declaration.
PrevDecl = 0;
} else if (PrevDecl) {
// C++ [temp]p5:
// A class template shall not have the same name as any other
// template, class, function, object, enumeration, enumerator,
// namespace, or type in the same scope (3.3), except as specified
// in (14.5.4).
Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
return true;
}
// Check the template parameter list of this declaration, possibly
// merging in the template parameter list from the previous class
// template declaration.
if (CheckTemplateParameterList(TemplateParams,
PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0))
Invalid = true;
// FIXME: If we had a scope specifier, we better have a previous template
// declaration!
CXXRecordDecl *NewClass =
CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc,
PrevClassTemplate?
PrevClassTemplate->getTemplatedDecl() : 0,
/*DelayTypeCreation=*/true);
ClassTemplateDecl *NewTemplate
= ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
DeclarationName(Name), TemplateParams,
NewClass, PrevClassTemplate);
NewClass->setDescribedClassTemplate(NewTemplate);
// Build the type for the class template declaration now.
QualType T =
Context.getTypeDeclType(NewClass,
PrevClassTemplate?
PrevClassTemplate->getTemplatedDecl() : 0);
assert(T->isDependentType() && "Class template type is not dependent?");
(void)T;
// Set the access specifier.
SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
// Set the lexical context of these templates
NewClass->setLexicalDeclContext(CurContext);
NewTemplate->setLexicalDeclContext(CurContext);
if (TUK == TUK_Definition)
NewClass->startDefinition();
if (Attr)
ProcessDeclAttributeList(S, NewClass, Attr);
PushOnScopeChains(NewTemplate, S);
if (Invalid) {
NewTemplate->setInvalidDecl();
NewClass->setInvalidDecl();
}
return DeclPtrTy::make(NewTemplate);
}
/// \brief Checks the validity of a template parameter list, possibly
/// considering the template parameter list from a previous
/// declaration.
///
/// If an "old" template parameter list is provided, it must be
/// equivalent (per TemplateParameterListsAreEqual) to the "new"
/// template parameter list.
///
/// \param NewParams Template parameter list for a new template
/// declaration. This template parameter list will be updated with any
/// default arguments that are carried through from the previous
/// template parameter list.
///
/// \param OldParams If provided, template parameter list from a
/// previous declaration of the same template. Default template
/// arguments will be merged from the old template parameter list to
/// the new template parameter list.
///
/// \returns true if an error occurred, false otherwise.
bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
TemplateParameterList *OldParams) {
bool Invalid = false;
// C++ [temp.param]p10:
// The set of default template-arguments available for use with a
// template declaration or definition is obtained by merging the
// default arguments from the definition (if in scope) and all
// declarations in scope in the same way default function
// arguments are (8.3.6).
bool SawDefaultArgument = false;
SourceLocation PreviousDefaultArgLoc;
bool SawParameterPack = false;
SourceLocation ParameterPackLoc;
// Dummy initialization to avoid warnings.
TemplateParameterList::iterator OldParam = NewParams->end();
if (OldParams)
OldParam = OldParams->begin();
for (TemplateParameterList::iterator NewParam = NewParams->begin(),
NewParamEnd = NewParams->end();
NewParam != NewParamEnd; ++NewParam) {
// Variables used to diagnose redundant default arguments
bool RedundantDefaultArg = false;
SourceLocation OldDefaultLoc;
SourceLocation NewDefaultLoc;
// Variables used to diagnose missing default arguments
bool MissingDefaultArg = false;
// C++0x [temp.param]p11:
// If a template parameter of a class template is a template parameter pack,
// it must be the last template parameter.
if (SawParameterPack) {
Diag(ParameterPackLoc,
diag::err_template_param_pack_must_be_last_template_parameter);
Invalid = true;
}
// Merge default arguments for template type parameters.
if (TemplateTypeParmDecl *NewTypeParm
= dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
TemplateTypeParmDecl *OldTypeParm
= OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
if (NewTypeParm->isParameterPack()) {
assert(!NewTypeParm->hasDefaultArgument() &&
"Parameter packs can't have a default argument!");
SawParameterPack = true;
ParameterPackLoc = NewTypeParm->getLocation();
} else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
NewTypeParm->hasDefaultArgument()) {
OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
SawDefaultArgument = true;
RedundantDefaultArg = true;
PreviousDefaultArgLoc = NewDefaultLoc;
} else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
// Merge the default argument from the old declaration to the
// new declaration.
SawDefaultArgument = true;
NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgument(),
OldTypeParm->getDefaultArgumentLoc(),
true);
PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
} else if (NewTypeParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
} else if (SawDefaultArgument)
MissingDefaultArg = true;
} else if (NonTypeTemplateParmDecl *NewNonTypeParm
= dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
// Merge default arguments for non-type template parameters
NonTypeTemplateParmDecl *OldNonTypeParm
= OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0;
if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
NewNonTypeParm->hasDefaultArgument()) {
OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
SawDefaultArgument = true;
RedundantDefaultArg = true;
PreviousDefaultArgLoc = NewDefaultLoc;
} else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
// Merge the default argument from the old declaration to the
// new declaration.
SawDefaultArgument = true;
// FIXME: We need to create a new kind of "default argument"
// expression that points to a previous template template
// parameter.
NewNonTypeParm->setDefaultArgument(
OldNonTypeParm->getDefaultArgument());
PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
} else if (NewNonTypeParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
} else if (SawDefaultArgument)
MissingDefaultArg = true;
} else {
// Merge default arguments for template template parameters
TemplateTemplateParmDecl *NewTemplateParm
= cast<TemplateTemplateParmDecl>(*NewParam);
TemplateTemplateParmDecl *OldTemplateParm
= OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
NewTemplateParm->hasDefaultArgument()) {
OldDefaultLoc = OldTemplateParm->getDefaultArgumentLoc();
NewDefaultLoc = NewTemplateParm->getDefaultArgumentLoc();
SawDefaultArgument = true;
RedundantDefaultArg = true;
PreviousDefaultArgLoc = NewDefaultLoc;
} else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
// Merge the default argument from the old declaration to the
// new declaration.
SawDefaultArgument = true;
// FIXME: We need to create a new kind of "default argument" expression
// that points to a previous template template parameter.
NewTemplateParm->setDefaultArgument(
OldTemplateParm->getDefaultArgument());
PreviousDefaultArgLoc = OldTemplateParm->getDefaultArgumentLoc();
} else if (NewTemplateParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc = NewTemplateParm->getDefaultArgumentLoc();
} else if (SawDefaultArgument)
MissingDefaultArg = true;
}
if (RedundantDefaultArg) {
// C++ [temp.param]p12:
// A template-parameter shall not be given default arguments
// by two different declarations in the same scope.
Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
Invalid = true;
} else if (MissingDefaultArg) {
// C++ [temp.param]p11:
// If a template-parameter has a default template-argument,
// all subsequent template-parameters shall have a default
// template-argument supplied.
Diag((*NewParam)->getLocation(),
diag::err_template_param_default_arg_missing);
Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
Invalid = true;
}
// If we have an old template parameter list that we're merging
// in, move on to the next parameter.
if (OldParams)
++OldParam;
}
return Invalid;
}
/// \brief Match the given template parameter lists to the given scope
/// specifier, returning the template parameter list that applies to the
/// name.
///
/// \param DeclStartLoc the start of the declaration that has a scope
/// specifier or a template parameter list.
///
/// \param SS the scope specifier that will be matched to the given template
/// parameter lists. This scope specifier precedes a qualified name that is
/// being declared.
///
/// \param ParamLists the template parameter lists, from the outermost to the
/// innermost template parameter lists.
///
/// \param NumParamLists the number of template parameter lists in ParamLists.
///
/// \returns the template parameter list, if any, that corresponds to the
/// name that is preceded by the scope specifier @p SS. This template
/// parameter list may be have template parameters (if we're declaring a
/// template) or may have no template parameters (if we're declaring a
/// template specialization), or may be NULL (if we were's declaring isn't
/// itself a template).
TemplateParameterList *
Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
const CXXScopeSpec &SS,
TemplateParameterList **ParamLists,
unsigned NumParamLists) {
// Find the template-ids that occur within the nested-name-specifier. These
// template-ids will match up with the template parameter lists.
llvm::SmallVector<const TemplateSpecializationType *, 4>
TemplateIdsInSpecifier;
for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
NNS; NNS = NNS->getPrefix()) {
if (const TemplateSpecializationType *SpecType
= dyn_cast_or_null<TemplateSpecializationType>(NNS->getAsType())) {
TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl();
if (!Template)
continue; // FIXME: should this be an error? probably...
if (const RecordType *Record = SpecType->getAs<RecordType>()) {
ClassTemplateSpecializationDecl *SpecDecl
= cast<ClassTemplateSpecializationDecl>(Record->getDecl());
// If the nested name specifier refers to an explicit specialization,
// we don't need a template<> header.
// FIXME: revisit this approach once we cope with specialization
// properly.
if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization)
continue;
}
TemplateIdsInSpecifier.push_back(SpecType);
}
}
// Reverse the list of template-ids in the scope specifier, so that we can
// more easily match up the template-ids and the template parameter lists.
std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end());
SourceLocation FirstTemplateLoc = DeclStartLoc;
if (NumParamLists)
FirstTemplateLoc = ParamLists[0]->getTemplateLoc();
// Match the template-ids found in the specifier to the template parameter
// lists.
unsigned Idx = 0;
for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size();
Idx != NumTemplateIds; ++Idx) {
QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0);
bool DependentTemplateId = TemplateId->isDependentType();
if (Idx >= NumParamLists) {
// We have a template-id without a corresponding template parameter
// list.
if (DependentTemplateId) {
// FIXME: the location information here isn't great.
Diag(SS.getRange().getBegin(),
diag::err_template_spec_needs_template_parameters)
<< TemplateId
<< SS.getRange();
} else {
Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header)
<< SS.getRange()
<< CodeModificationHint::CreateInsertion(FirstTemplateLoc,
"template<> ");
}
return 0;
}
// Check the template parameter list against its corresponding template-id.
if (DependentTemplateId) {
TemplateDecl *Template
= TemplateIdsInSpecifier[Idx]->getTemplateName().getAsTemplateDecl();
if (ClassTemplateDecl *ClassTemplate
= dyn_cast<ClassTemplateDecl>(Template)) {
TemplateParameterList *ExpectedTemplateParams = 0;
// Is this template-id naming the primary template?
if (Context.hasSameType(TemplateId,
ClassTemplate->getInjectedClassNameType(Context)))
ExpectedTemplateParams = ClassTemplate->getTemplateParameters();
// ... or a partial specialization?
else if (ClassTemplatePartialSpecializationDecl *PartialSpec
= ClassTemplate->findPartialSpecialization(TemplateId))
ExpectedTemplateParams = PartialSpec->getTemplateParameters();
if (ExpectedTemplateParams)
TemplateParameterListsAreEqual(ParamLists[Idx],
ExpectedTemplateParams,
true);
}
} else if (ParamLists[Idx]->size() > 0)
Diag(ParamLists[Idx]->getTemplateLoc(),
diag::err_template_param_list_matches_nontemplate)
<< TemplateId
<< ParamLists[Idx]->getSourceRange();
}
// If there were at least as many template-ids as there were template
// parameter lists, then there are no template parameter lists remaining for
// the declaration itself.
if (Idx >= NumParamLists)
return 0;
// If there were too many template parameter lists, complain about that now.
if (Idx != NumParamLists - 1) {
while (Idx < NumParamLists - 1) {
Diag(ParamLists[Idx]->getTemplateLoc(),
diag::err_template_spec_extra_headers)
<< SourceRange(ParamLists[Idx]->getTemplateLoc(),
ParamLists[Idx]->getRAngleLoc());
++Idx;
}
}
// Return the last template parameter list, which corresponds to the
// entity being declared.
return ParamLists[NumParamLists - 1];
}
/// \brief Translates template arguments as provided by the parser
/// into template arguments used by semantic analysis.
static void
translateTemplateArguments(ASTTemplateArgsPtr &TemplateArgsIn,
SourceLocation *TemplateArgLocs,
llvm::SmallVector<TemplateArgument, 16> &TemplateArgs) {
TemplateArgs.reserve(TemplateArgsIn.size());
void **Args = TemplateArgsIn.getArgs();
bool *ArgIsType = TemplateArgsIn.getArgIsType();
for (unsigned Arg = 0, Last = TemplateArgsIn.size(); Arg != Last; ++Arg) {
TemplateArgs.push_back(
ArgIsType[Arg]? TemplateArgument(TemplateArgLocs[Arg],
//FIXME: Preserve type source info.
Sema::GetTypeFromParser(Args[Arg]))
: TemplateArgument(reinterpret_cast<Expr *>(Args[Arg])));
}
}
QualType Sema::CheckTemplateIdType(TemplateName Name,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc) {
TemplateDecl *Template = Name.getAsTemplateDecl();
if (!Template) {
// The template name does not resolve to a template, so we just
// build a dependent template-id type.
return Context.getTemplateSpecializationType(Name, TemplateArgs,
NumTemplateArgs);
}
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(Template->getTemplateParameters(),
NumTemplateArgs);
if (CheckTemplateArgumentList(Template, TemplateLoc, LAngleLoc,
TemplateArgs, NumTemplateArgs, RAngleLoc,
false, Converted))
return QualType();
assert((Converted.structuredSize() ==
Template->getTemplateParameters()->size()) &&
"Converted template argument list is too short!");
QualType CanonType;
if (TemplateSpecializationType::anyDependentTemplateArguments(
TemplateArgs,
NumTemplateArgs)) {
// This class template specialization is a dependent
// type. Therefore, its canonical type is another class template
// specialization type that contains all of the converted
// arguments in canonical form. This ensures that, e.g., A<T> and
// A<T, T> have identical types when A is declared as:
//
// template<typename T, typename U = T> struct A;
TemplateName CanonName = Context.getCanonicalTemplateName(Name);
CanonType = Context.getTemplateSpecializationType(CanonName,
Converted.getFlatArguments(),
Converted.flatSize());
// FIXME: CanonType is not actually the canonical type, and unfortunately
// it is a TemplateTypeSpecializationType that we will never use again.
// In the future, we need to teach getTemplateSpecializationType to only
// build the canonical type and return that to us.
CanonType = Context.getCanonicalType(CanonType);
} else if (ClassTemplateDecl *ClassTemplate
= dyn_cast<ClassTemplateDecl>(Template)) {
// Find the class template specialization declaration that
// corresponds to these arguments.
llvm::FoldingSetNodeID ID;
ClassTemplateSpecializationDecl::Profile(ID,
Converted.getFlatArguments(),
Converted.flatSize(),
Context);
void *InsertPos = 0;
ClassTemplateSpecializationDecl *Decl
= ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
if (!Decl) {
// This is the first time we have referenced this class template
// specialization. Create the canonical declaration and add it to
// the set of specializations.
Decl = ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateLoc,
ClassTemplate,
Converted, 0);
ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos);
Decl->setLexicalDeclContext(CurContext);
}
CanonType = Context.getTypeDeclType(Decl);
}
// Build the fully-sugared type for this class template
// specialization, which refers back to the class template
// specialization we created or found.
//FIXME: Preserve type source info.
return Context.getTemplateSpecializationType(Name, TemplateArgs,
NumTemplateArgs, CanonType);
}
Action::TypeResult
Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc) {
TemplateName Template = TemplateD.getAsVal<TemplateName>();
// Translate the parser's template argument list in our AST format.
llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
translateTemplateArguments(TemplateArgsIn, TemplateArgLocs, TemplateArgs);
QualType Result = CheckTemplateIdType(Template, TemplateLoc, LAngleLoc,
TemplateArgs.data(),
TemplateArgs.size(),
RAngleLoc);
TemplateArgsIn.release();
if (Result.isNull())
return true;
return Result.getAsOpaquePtr();
}
Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
TagUseKind TUK,
DeclSpec::TST TagSpec,
SourceLocation TagLoc) {
if (TypeResult.isInvalid())
return Sema::TypeResult();
QualType Type = QualType::getFromOpaquePtr(TypeResult.get());
// Verify the tag specifier.
TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec);
if (const RecordType *RT = Type->getAs<RecordType>()) {
RecordDecl *D = RT->getDecl();
IdentifierInfo *Id = D->getIdentifier();
assert(Id && "templated class must have an identifier");
if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) {
Diag(TagLoc, diag::err_use_with_wrong_tag)
<< Id
<< CodeModificationHint::CreateReplacement(SourceRange(TagLoc),
D->getKindName());
}
}
QualType ElabType = Context.getElaboratedType(Type, TagKind);
return ElabType.getAsOpaquePtr();
}
Sema::OwningExprResult Sema::BuildTemplateIdExpr(TemplateName Template,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc) {
// FIXME: Can we do any checking at this point? I guess we could check the
// template arguments that we have against the template name, if the template
// name refers to a single template. That's not a terribly common case,
// though.
return Owned(TemplateIdRefExpr::Create(Context,
/*FIXME: New type?*/Context.OverloadTy,
/*FIXME: Necessary?*/0,
/*FIXME: Necessary?*/SourceRange(),
Template, TemplateNameLoc, LAngleLoc,
TemplateArgs,
NumTemplateArgs, RAngleLoc));
}
Sema::OwningExprResult Sema::ActOnTemplateIdExpr(TemplateTy TemplateD,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc) {
TemplateName Template = TemplateD.getAsVal<TemplateName>();
// Translate the parser's template argument list in our AST format.
llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
translateTemplateArguments(TemplateArgsIn, TemplateArgLocs, TemplateArgs);
TemplateArgsIn.release();
return BuildTemplateIdExpr(Template, TemplateNameLoc, LAngleLoc,
TemplateArgs.data(), TemplateArgs.size(),
RAngleLoc);
}
Sema::OwningExprResult
Sema::ActOnMemberTemplateIdReferenceExpr(Scope *S, ExprArg Base,
SourceLocation OpLoc,
tok::TokenKind OpKind,
const CXXScopeSpec &SS,
TemplateTy TemplateD,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc) {
TemplateName Template = TemplateD.getAsVal<TemplateName>();
// FIXME: We're going to end up looking up the template based on its name,
// twice!
DeclarationName Name;
if (TemplateDecl *ActualTemplate = Template.getAsTemplateDecl())
Name = ActualTemplate->getDeclName();
else if (OverloadedFunctionDecl *Ovl = Template.getAsOverloadedFunctionDecl())
Name = Ovl->getDeclName();
else
assert(false && "Cannot support dependent template names yet");
// Translate the parser's template argument list in our AST format.
llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
translateTemplateArguments(TemplateArgsIn, TemplateArgLocs, TemplateArgs);
TemplateArgsIn.release();
// Do we have the save the actual template name? We might need it...
return BuildMemberReferenceExpr(S, move(Base), OpLoc, OpKind, TemplateNameLoc,
Name, true, LAngleLoc,
TemplateArgs.data(), TemplateArgs.size(),
RAngleLoc, DeclPtrTy(), &SS);
}
/// \brief Form a dependent template name.
///
/// This action forms a dependent template name given the template
/// name and its (presumably dependent) scope specifier. For
/// example, given "MetaFun::template apply", the scope specifier \p
/// SS will be "MetaFun::", \p TemplateKWLoc contains the location
/// of the "template" keyword, and "apply" is the \p Name.
Sema::TemplateTy
Sema::ActOnDependentTemplateName(SourceLocation TemplateKWLoc,
const IdentifierInfo &Name,
SourceLocation NameLoc,
const CXXScopeSpec &SS,
TypeTy *ObjectType) {
if ((ObjectType &&
computeDeclContext(QualType::getFromOpaquePtr(ObjectType))) ||
(SS.isSet() && computeDeclContext(SS, false))) {
// C++0x [temp.names]p5:
// If a name prefixed by the keyword template is not the name of
// a template, the program is ill-formed. [Note: the keyword
// template may not be applied to non-template members of class
// templates. -end note ] [ Note: as is the case with the
// typename prefix, the template prefix is allowed in cases
// where it is not strictly necessary; i.e., when the
// nested-name-specifier or the expression on the left of the ->
// or . is not dependent on a template-parameter, or the use
// does not appear in the scope of a template. -end note]
//
// Note: C++03 was more strict here, because it banned the use of
// the "template" keyword prior to a template-name that was not a
// dependent name. C++ DR468 relaxed this requirement (the
// "template" keyword is now permitted). We follow the C++0x
// rules, even in C++03 mode, retroactively applying the DR.
TemplateTy Template;
TemplateNameKind TNK = isTemplateName(0, Name, NameLoc, &SS, ObjectType,
false, Template);
if (TNK == TNK_Non_template) {
Diag(NameLoc, diag::err_template_kw_refers_to_non_template)
<< &Name;
return TemplateTy();
}
return Template;
}
// FIXME: We need to be able to create a dependent template name with just
// an identifier, to handle the x->template f<T> case.
assert(!ObjectType &&
"Cannot handle dependent template names without a nested-name-specifier");
NestedNameSpecifier *Qualifier
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
return TemplateTy::make(Context.getDependentTemplateName(Qualifier, &Name));
}
bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
const TemplateArgument &Arg,
TemplateArgumentListBuilder &Converted) {
// Check template type parameter.
if (Arg.getKind() != TemplateArgument::Type) {
// C++ [temp.arg.type]p1:
// A template-argument for a template-parameter which is a
// type shall be a type-id.
// We have a template type parameter but the template argument
// is not a type.
Diag(Arg.getLocation(), diag::err_template_arg_must_be_type);
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
if (CheckTemplateArgument(Param, Arg.getAsType(), Arg.getLocation()))
return true;
// Add the converted template type argument.
Converted.Append(
TemplateArgument(Arg.getLocation(),
Context.getCanonicalType(Arg.getAsType())));
return false;
}
/// \brief Check that the given template argument list is well-formed
/// for specializing the given template.
bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc,
bool PartialTemplateArgs,
TemplateArgumentListBuilder &Converted) {
TemplateParameterList *Params = Template->getTemplateParameters();
unsigned NumParams = Params->size();
unsigned NumArgs = NumTemplateArgs;
bool Invalid = false;
bool HasParameterPack =
NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack();
if ((NumArgs > NumParams && !HasParameterPack) ||
(NumArgs < Params->getMinRequiredArguments() &&
!PartialTemplateArgs)) {
// FIXME: point at either the first arg beyond what we can handle,
// or the '>', depending on whether we have too many or too few
// arguments.
SourceRange Range;
if (NumArgs > NumParams)
Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc);
Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
<< (NumArgs > NumParams)
<< (isa<ClassTemplateDecl>(Template)? 0 :
isa<FunctionTemplateDecl>(Template)? 1 :
isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
<< Template << Range;
Diag(Template->getLocation(), diag::note_template_decl_here)
<< Params->getSourceRange();
Invalid = true;
}
// C++ [temp.arg]p1:
// [...] The type and form of each template-argument specified in
// a template-id shall match the type and form specified for the
// corresponding parameter declared by the template in its
// template-parameter-list.
unsigned ArgIdx = 0;
for (TemplateParameterList::iterator Param = Params->begin(),
ParamEnd = Params->end();
Param != ParamEnd; ++Param, ++ArgIdx) {
if (ArgIdx > NumArgs && PartialTemplateArgs)
break;
// Decode the template argument
TemplateArgument Arg;
if (ArgIdx >= NumArgs) {
// Retrieve the default template argument from the template
// parameter.
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
if (TTP->isParameterPack()) {
// We have an empty argument pack.
Converted.BeginPack();
Converted.EndPack();
break;
}
if (!TTP->hasDefaultArgument())
break;
QualType ArgType = TTP->getDefaultArgument();
// If the argument type is dependent, instantiate it now based
// on the previously-computed template arguments.
if (ArgType->isDependentType()) {
InstantiatingTemplate Inst(*this, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
TemplateArgumentList TemplateArgs(Context, Converted,
/*TakeArgs=*/false);
ArgType = SubstType(ArgType,
MultiLevelTemplateArgumentList(TemplateArgs),
TTP->getDefaultArgumentLoc(),
TTP->getDeclName());
}
if (ArgType.isNull())
return true;
Arg = TemplateArgument(TTP->getLocation(), ArgType);
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
if (!NTTP->hasDefaultArgument())
break;
InstantiatingTemplate Inst(*this, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
TemplateArgumentList TemplateArgs(Context, Converted,
/*TakeArgs=*/false);
Sema::OwningExprResult E
= SubstExpr(NTTP->getDefaultArgument(),
MultiLevelTemplateArgumentList(TemplateArgs));
if (E.isInvalid())
return true;
Arg = TemplateArgument(E.takeAs<Expr>());
} else {
TemplateTemplateParmDecl *TempParm
= cast<TemplateTemplateParmDecl>(*Param);
if (!TempParm->hasDefaultArgument())
break;
// FIXME: Subst default argument
Arg = TemplateArgument(TempParm->getDefaultArgument());
}
} else {
// Retrieve the template argument produced by the user.
Arg = TemplateArgs[ArgIdx];
}
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
if (TTP->isParameterPack()) {
Converted.BeginPack();
// Check all the remaining arguments (if any).
for (; ArgIdx < NumArgs; ++ArgIdx) {
if (CheckTemplateTypeArgument(TTP, TemplateArgs[ArgIdx], Converted))
Invalid = true;
}
Converted.EndPack();
} else {
if (CheckTemplateTypeArgument(TTP, Arg, Converted))
Invalid = true;
}
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
// Check non-type template parameters.
// Do substitution on the type of the non-type template parameter
// with the template arguments we've seen thus far.
QualType NTTPType = NTTP->getType();
if (NTTPType->isDependentType()) {
// Do substitution on the type of the non-type template parameter.
InstantiatingTemplate Inst(*this, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
TemplateArgumentList TemplateArgs(Context, Converted,
/*TakeArgs=*/false);
NTTPType = SubstType(NTTPType,
MultiLevelTemplateArgumentList(TemplateArgs),
NTTP->getLocation(),
NTTP->getDeclName());
// If that worked, check the non-type template parameter type
// for validity.
if (!NTTPType.isNull())
NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
NTTP->getLocation());
if (NTTPType.isNull()) {
Invalid = true;
break;
}
}
switch (Arg.getKind()) {
case TemplateArgument::Null:
assert(false && "Should never see a NULL template argument here");
break;
case TemplateArgument::Expression: {
Expr *E = Arg.getAsExpr();
TemplateArgument Result;
if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
Invalid = true;
else
Converted.Append(Result);
break;
}
case TemplateArgument::Declaration:
case TemplateArgument::Integral:
// We've already checked this template argument, so just copy
// it to the list of converted arguments.
Converted.Append(Arg);
break;
case TemplateArgument::Type:
// We have a non-type template parameter but the template
// argument is a type.
// C++ [temp.arg]p2:
// In a template-argument, an ambiguity between a type-id and
// an expression is resolved to a type-id, regardless of the
// form of the corresponding template-parameter.
//
// We warn specifically about this case, since it can be rather
// confusing for users.
if (Arg.getAsType()->isFunctionType())
Diag(Arg.getLocation(), diag::err_template_arg_nontype_ambig)
<< Arg.getAsType();
else
Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr);
Diag((*Param)->getLocation(), diag::note_template_param_here);
Invalid = true;
break;
case TemplateArgument::Pack:
assert(0 && "FIXME: Implement!");
break;
}
} else {
// Check template template parameters.
TemplateTemplateParmDecl *TempParm
= cast<TemplateTemplateParmDecl>(*Param);
switch (Arg.getKind()) {
case TemplateArgument::Null:
assert(false && "Should never see a NULL template argument here");
break;
case TemplateArgument::Expression: {
Expr *ArgExpr = Arg.getAsExpr();
if (ArgExpr && isa<DeclRefExpr>(ArgExpr) &&
isa<TemplateDecl>(cast<DeclRefExpr>(ArgExpr)->getDecl())) {
if (CheckTemplateArgument(TempParm, cast<DeclRefExpr>(ArgExpr)))
Invalid = true;
// Add the converted template argument.
Decl *D
= cast<DeclRefExpr>(ArgExpr)->getDecl()->getCanonicalDecl();
Converted.Append(TemplateArgument(Arg.getLocation(), D));
continue;
}
}
// fall through
case TemplateArgument::Type: {
// We have a template template parameter but the template
// argument does not refer to a template.
Diag(Arg.getLocation(), diag::err_template_arg_must_be_template);
Invalid = true;
break;
}
case TemplateArgument::Declaration:
// We've already checked this template argument, so just copy
// it to the list of converted arguments.
Converted.Append(Arg);
break;
case TemplateArgument::Integral:
assert(false && "Integral argument with template template parameter");
break;
case TemplateArgument::Pack:
assert(0 && "FIXME: Implement!");
break;
}
}
}
return Invalid;
}
/// \brief Check a template argument against its corresponding
/// template type parameter.
///
/// This routine implements the semantics of C++ [temp.arg.type]. It
/// returns true if an error occurred, and false otherwise.
bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
QualType Arg, SourceLocation ArgLoc) {
// C++ [temp.arg.type]p2:
// A local type, a type with no linkage, an unnamed type or a type
// compounded from any of these types shall not be used as a
// template-argument for a template type-parameter.
//
// FIXME: Perform the recursive and no-linkage type checks.
const TagType *Tag = 0;
if (const EnumType *EnumT = Arg->getAsEnumType())
Tag = EnumT;
else if (const RecordType *RecordT = Arg->getAs<RecordType>())
Tag = RecordT;
if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod())
return Diag(ArgLoc, diag::err_template_arg_local_type)
<< QualType(Tag, 0);
else if (Tag && !Tag->getDecl()->getDeclName() &&
!Tag->getDecl()->getTypedefForAnonDecl()) {
Diag(ArgLoc, diag::err_template_arg_unnamed_type);
Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here);
return true;
}
return false;
}
/// \brief Checks whether the given template argument is the address
/// of an object or function according to C++ [temp.arg.nontype]p1.
bool Sema::CheckTemplateArgumentAddressOfObjectOrFunction(Expr *Arg,
NamedDecl *&Entity) {
bool Invalid = false;
// See through any implicit casts we added to fix the type.
if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
Arg = Cast->getSubExpr();
// C++0x allows nullptr, and there's no further checking to be done for that.
if (Arg->getType()->isNullPtrType())
return false;
// C++ [temp.arg.nontype]p1:
//
// A template-argument for a non-type, non-template
// template-parameter shall be one of: [...]
//
// -- the address of an object or function with external
// linkage, including function templates and function
// template-ids but excluding non-static class members,
// expressed as & id-expression where the & is optional if
// the name refers to a function or array, or if the
// corresponding template-parameter is a reference; or
DeclRefExpr *DRE = 0;
// Ignore (and complain about) any excess parentheses.
while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
if (!Invalid) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_extra_parens)
<< Arg->getSourceRange();
Invalid = true;
}
Arg = Parens->getSubExpr();
}
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
if (UnOp->getOpcode() == UnaryOperator::AddrOf)
DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
} else
DRE = dyn_cast<DeclRefExpr>(Arg);
if (!DRE || !isa<ValueDecl>(DRE->getDecl()))
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_object_or_func_form)
<< Arg->getSourceRange();
// Cannot refer to non-static data members
if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl()))
return Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field)
<< Field << Arg->getSourceRange();
// Cannot refer to non-static member functions
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl()))
if (!Method->isStatic())
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_method)
<< Method << Arg->getSourceRange();
// Functions must have external linkage.
if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) {
if (Func->getStorageClass() == FunctionDecl::Static) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_function_not_extern)
<< Func << Arg->getSourceRange();
Diag(Func->getLocation(), diag::note_template_arg_internal_object)
<< true;
return true;
}
// Okay: we've named a function with external linkage.
Entity = Func;
return Invalid;
}
if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
if (!Var->hasGlobalStorage()) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_object_not_extern)
<< Var << Arg->getSourceRange();
Diag(Var->getLocation(), diag::note_template_arg_internal_object)
<< true;
return true;
}
// Okay: we've named an object with external linkage
Entity = Var;
return Invalid;
}
// We found something else, but we don't know specifically what it is.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_object_or_func)
<< Arg->getSourceRange();
Diag(DRE->getDecl()->getLocation(),
diag::note_template_arg_refers_here);
return true;
}
/// \brief Checks whether the given template argument is a pointer to
/// member constant according to C++ [temp.arg.nontype]p1.
bool
Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, NamedDecl *&Member) {
bool Invalid = false;
// See through any implicit casts we added to fix the type.
if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
Arg = Cast->getSubExpr();
// C++0x allows nullptr, and there's no further checking to be done for that.
if (Arg->getType()->isNullPtrType())
return false;
// C++ [temp.arg.nontype]p1:
//
// A template-argument for a non-type, non-template
// template-parameter shall be one of: [...]
//
// -- a pointer to member expressed as described in 5.3.1.
QualifiedDeclRefExpr *DRE = 0;
// Ignore (and complain about) any excess parentheses.
while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
if (!Invalid) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_extra_parens)
<< Arg->getSourceRange();
Invalid = true;
}
Arg = Parens->getSubExpr();
}
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg))
if (UnOp->getOpcode() == UnaryOperator::AddrOf)
DRE = dyn_cast<QualifiedDeclRefExpr>(UnOp->getSubExpr());
if (!DRE)
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_pointer_to_member_form)
<< Arg->getSourceRange();
if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
assert((isa<FieldDecl>(DRE->getDecl()) ||
!cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
"Only non-static member pointers can make it here");
// Okay: this is the address of a non-static member, and therefore
// a member pointer constant.
Member = DRE->getDecl();
return Invalid;
}
// We found something else, but we don't know specifically what it is.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_pointer_to_member_form)
<< Arg->getSourceRange();
Diag(DRE->getDecl()->getLocation(),
diag::note_template_arg_refers_here);
return true;
}
/// \brief Check a template argument against its corresponding
/// non-type template parameter.
///
/// This routine implements the semantics of C++ [temp.arg.nontype].
/// It returns true if an error occurred, and false otherwise. \p
/// InstantiatedParamType is the type of the non-type template
/// parameter after it has been instantiated.
///
/// If no error was detected, Converted receives the converted template argument.
bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
QualType InstantiatedParamType, Expr *&Arg,
TemplateArgument &Converted) {
SourceLocation StartLoc = Arg->getSourceRange().getBegin();
// If either the parameter has a dependent type or the argument is
// type-dependent, there's nothing we can check now.
// FIXME: Add template argument to Converted!
if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
// FIXME: Produce a cloned, canonical expression?
Converted = TemplateArgument(Arg);
return false;
}
// C++ [temp.arg.nontype]p5:
// The following conversions are performed on each expression used
// as a non-type template-argument. If a non-type
// template-argument cannot be converted to the type of the
// corresponding template-parameter then the program is
// ill-formed.
//
// -- for a non-type template-parameter of integral or
// enumeration type, integral promotions (4.5) and integral
// conversions (4.7) are applied.
QualType ParamType = InstantiatedParamType;
QualType ArgType = Arg->getType();
if (ParamType->isIntegralType() || ParamType->isEnumeralType()) {
// C++ [temp.arg.nontype]p1:
// A template-argument for a non-type, non-template
// template-parameter shall be one of:
//
// -- an integral constant-expression of integral or enumeration
// type; or
// -- the name of a non-type template-parameter; or
SourceLocation NonConstantLoc;
llvm::APSInt Value;
if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_integral_or_enumeral)
<< ArgType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
} else if (!Arg->isValueDependent() &&
!Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) {
Diag(NonConstantLoc, diag::err_template_arg_not_ice)
<< ArgType << Arg->getSourceRange();
return true;
}
// FIXME: We need some way to more easily get the unqualified form
// of the types without going all the way to the
// canonical type.
if (Context.getCanonicalType(ParamType).getCVRQualifiers())
ParamType = Context.getCanonicalType(ParamType).getUnqualifiedType();
if (Context.getCanonicalType(ArgType).getCVRQualifiers())
ArgType = Context.getCanonicalType(ArgType).getUnqualifiedType();
// Try to convert the argument to the parameter's type.
if (ParamType == ArgType) {
// Okay: no conversion necessary
} else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
!ParamType->isEnumeralType()) {
// This is an integral promotion or conversion.
ImpCastExprToType(Arg, ParamType);
} else {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
QualType IntegerType = Context.getCanonicalType(ParamType);
if (const EnumType *Enum = IntegerType->getAsEnumType())
IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
if (!Arg->isValueDependent()) {
// Check that an unsigned parameter does not receive a negative
// value.
if (IntegerType->isUnsignedIntegerType()
&& (Value.isSigned() && Value.isNegative())) {
Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_negative)
<< Value.toString(10) << Param->getType()
<< Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
// Check that we don't overflow the template parameter type.
unsigned AllowedBits = Context.getTypeSize(IntegerType);
if (Value.getActiveBits() > AllowedBits) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_too_large)
<< Value.toString(10) << Param->getType()
<< Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
if (Value.getBitWidth() != AllowedBits)
Value.extOrTrunc(AllowedBits);
Value.setIsSigned(IntegerType->isSignedIntegerType());
}
// Add the value of this argument to the list of converted
// arguments. We use the bitwidth and signedness of the template
// parameter.
if (Arg->isValueDependent()) {
// The argument is value-dependent. Create a new
// TemplateArgument with the converted expression.
Converted = TemplateArgument(Arg);
return false;
}
Converted = TemplateArgument(StartLoc, Value,
ParamType->isEnumeralType() ? ParamType
: IntegerType);
return false;
}
// Handle pointer-to-function, reference-to-function, and
// pointer-to-member-function all in (roughly) the same way.
if (// -- For a non-type template-parameter of type pointer to
// function, only the function-to-pointer conversion (4.3) is
// applied. If the template-argument represents a set of
// overloaded functions (or a pointer to such), the matching
// function is selected from the set (13.4).
// In C++0x, any std::nullptr_t value can be converted.
(ParamType->isPointerType() &&
ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
// -- For a non-type template-parameter of type reference to
// function, no conversions apply. If the template-argument
// represents a set of overloaded functions, the matching
// function is selected from the set (13.4).
(ParamType->isReferenceType() &&
ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
// -- For a non-type template-parameter of type pointer to
// member function, no conversions apply. If the
// template-argument represents a set of overloaded member
// functions, the matching member function is selected from
// the set (13.4).
// Again, C++0x allows a std::nullptr_t value.
(ParamType->isMemberPointerType() &&
ParamType->getAs<MemberPointerType>()->getPointeeType()
->isFunctionType())) {
if (Context.hasSameUnqualifiedType(ArgType,
ParamType.getNonReferenceType())) {
// We don't have to do anything: the types already match.
} else if (ArgType->isNullPtrType() && (ParamType->isPointerType() ||
ParamType->isMemberPointerType())) {
ArgType = ParamType;
ImpCastExprToType(Arg, ParamType);
} else if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(ArgType);
ImpCastExprToType(Arg, ArgType);
} else if (FunctionDecl *Fn
= ResolveAddressOfOverloadedFunction(Arg, ParamType, true)) {
if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
return true;
FixOverloadedFunctionReference(Arg, Fn);
ArgType = Arg->getType();
if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(Arg->getType());
ImpCastExprToType(Arg, ArgType);
}
}
if (!Context.hasSameUnqualifiedType(ArgType,
ParamType.getNonReferenceType())) {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
if (ParamType->isMemberPointerType()) {
NamedDecl *Member = 0;
if (CheckTemplateArgumentPointerToMember(Arg, Member))
return true;
if (Member)
Member = cast<NamedDecl>(Member->getCanonicalDecl());
Converted = TemplateArgument(StartLoc, Member);
return false;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Entity)
Entity = cast<NamedDecl>(Entity->getCanonicalDecl());
Converted = TemplateArgument(StartLoc, Entity);
return false;
}
if (ParamType->isPointerType()) {
// -- for a non-type template-parameter of type pointer to
// object, qualification conversions (4.4) and the
// array-to-pointer conversion (4.2) are applied.
// C++0x also allows a value of std::nullptr_t.
assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() &&
"Only object pointers allowed here");
if (ArgType->isNullPtrType()) {
ArgType = ParamType;
ImpCastExprToType(Arg, ParamType);
} else if (ArgType->isArrayType()) {
ArgType = Context.getArrayDecayedType(ArgType);
ImpCastExprToType(Arg, ArgType);
}
if (IsQualificationConversion(ArgType, ParamType)) {
ArgType = ParamType;
ImpCastExprToType(Arg, ParamType);
}
if (!Context.hasSameUnqualifiedType(ArgType, ParamType)) {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Entity)
Entity = cast<NamedDecl>(Entity->getCanonicalDecl());
Converted = TemplateArgument(StartLoc, Entity);
return false;
}
if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
// -- For a non-type template-parameter of type reference to
// object, no conversions apply. The type referred to by the
// reference may be more cv-qualified than the (otherwise
// identical) type of the template-argument. The
// template-parameter is bound directly to the
// template-argument, which must be an lvalue.
assert(ParamRefType->getPointeeType()->isObjectType() &&
"Only object references allowed here");
if (!Context.hasSameUnqualifiedType(ParamRefType->getPointeeType(), ArgType)) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_no_ref_bind)
<< InstantiatedParamType << Arg->getType()
<< Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
unsigned ParamQuals
= Context.getCanonicalType(ParamType).getCVRQualifiers();
unsigned ArgQuals = Context.getCanonicalType(ArgType).getCVRQualifiers();
if ((ParamQuals | ArgQuals) != ParamQuals) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_ref_bind_ignores_quals)
<< InstantiatedParamType << Arg->getType()
<< Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
Entity = cast<NamedDecl>(Entity->getCanonicalDecl());
Converted = TemplateArgument(StartLoc, Entity);
return false;
}
// -- For a non-type template-parameter of type pointer to data
// member, qualification conversions (4.4) are applied.
// C++0x allows std::nullptr_t values.
assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
if (Context.hasSameUnqualifiedType(ParamType, ArgType)) {
// Types match exactly: nothing more to do here.
} else if (ArgType->isNullPtrType()) {
ImpCastExprToType(Arg, ParamType);
} else if (IsQualificationConversion(ArgType, ParamType)) {
ImpCastExprToType(Arg, ParamType);
} else {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Member = 0;
if (CheckTemplateArgumentPointerToMember(Arg, Member))
return true;
if (Member)
Member = cast<NamedDecl>(Member->getCanonicalDecl());
Converted = TemplateArgument(StartLoc, Member);
return false;
}
/// \brief Check a template argument against its corresponding
/// template template parameter.
///
/// This routine implements the semantics of C++ [temp.arg.template].
/// It returns true if an error occurred, and false otherwise.
bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
DeclRefExpr *Arg) {
assert(isa<TemplateDecl>(Arg->getDecl()) && "Only template decls allowed");
TemplateDecl *Template = cast<TemplateDecl>(Arg->getDecl());
// C++ [temp.arg.template]p1:
// A template-argument for a template template-parameter shall be
// the name of a class template, expressed as id-expression. Only
// primary class templates are considered when matching the
// template template argument with the corresponding parameter;
// partial specializations are not considered even if their
// parameter lists match that of the template template parameter.
//
// Note that we also allow template template parameters here, which
// will happen when we are dealing with, e.g., class template
// partial specializations.
if (!isa<ClassTemplateDecl>(Template) &&
!isa<TemplateTemplateParmDecl>(Template)) {
assert(isa<FunctionTemplateDecl>(Template) &&
"Only function templates are possible here");
Diag(Arg->getLocStart(), diag::err_template_arg_not_class_template);
Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
<< Template;
}
return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
Param->getTemplateParameters(),
true, true,
Arg->getSourceRange().getBegin());
}
/// \brief Determine whether the given template parameter lists are
/// equivalent.
///
/// \param New The new template parameter list, typically written in the
/// source code as part of a new template declaration.
///
/// \param Old The old template parameter list, typically found via
/// name lookup of the template declared with this template parameter
/// list.
///
/// \param Complain If true, this routine will produce a diagnostic if
/// the template parameter lists are not equivalent.
///
/// \param IsTemplateTemplateParm If true, this routine is being
/// called to compare the template parameter lists of a template
/// template parameter.
///
/// \param TemplateArgLoc If this source location is valid, then we
/// are actually checking the template parameter list of a template
/// argument (New) against the template parameter list of its
/// corresponding template template parameter (Old). We produce
/// slightly different diagnostics in this scenario.
///
/// \returns True if the template parameter lists are equal, false
/// otherwise.
bool
Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
TemplateParameterList *Old,
bool Complain,
bool IsTemplateTemplateParm,
SourceLocation TemplateArgLoc) {
if (Old->size() != New->size()) {
if (Complain) {
unsigned NextDiag = diag::err_template_param_list_different_arity;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_param_list_different_arity;
}
Diag(New->getTemplateLoc(), NextDiag)
<< (New->size() > Old->size())
<< IsTemplateTemplateParm
<< SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
<< IsTemplateTemplateParm
<< SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
}
return false;
}
for (TemplateParameterList::iterator OldParm = Old->begin(),
OldParmEnd = Old->end(), NewParm = New->begin();
OldParm != OldParmEnd; ++OldParm, ++NewParm) {
if ((*OldParm)->getKind() != (*NewParm)->getKind()) {
if (Complain) {
unsigned NextDiag = diag::err_template_param_different_kind;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_param_different_kind;
}
Diag((*NewParm)->getLocation(), NextDiag)
<< IsTemplateTemplateParm;
Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration)
<< IsTemplateTemplateParm;
}
return false;
}
if (isa<TemplateTypeParmDecl>(*OldParm)) {
// Okay; all template type parameters are equivalent (since we
// know we're at the same index).
#if 0
// FIXME: Enable this code in debug mode *after* we properly go through
// and "instantiate" the template parameter lists of template template
// parameters. It's only after this instantiation that (1) any dependent
// types within the template parameter list of the template template
// parameter can be checked, and (2) the template type parameter depths
// will match up.
QualType OldParmType
= Context.getTypeDeclType(cast<TemplateTypeParmDecl>(*OldParm));
QualType NewParmType
= Context.getTypeDeclType(cast<TemplateTypeParmDecl>(*NewParm));
assert(Context.getCanonicalType(OldParmType) ==
Context.getCanonicalType(NewParmType) &&
"type parameter mismatch?");
#endif
} else if (NonTypeTemplateParmDecl *OldNTTP
= dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
// The types of non-type template parameters must agree.
NonTypeTemplateParmDecl *NewNTTP
= cast<NonTypeTemplateParmDecl>(*NewParm);
if (Context.getCanonicalType(OldNTTP->getType()) !=
Context.getCanonicalType(NewNTTP->getType())) {
if (Complain) {
unsigned NextDiag = diag::err_template_nontype_parm_different_type;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc,
diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_nontype_parm_different_type;
}
Diag(NewNTTP->getLocation(), NextDiag)
<< NewNTTP->getType()
<< IsTemplateTemplateParm;
Diag(OldNTTP->getLocation(),
diag::note_template_nontype_parm_prev_declaration)
<< OldNTTP->getType();
}
return false;
}
} else {
// The template parameter lists of template template
// parameters must agree.
// FIXME: Could we perform a faster "type" comparison here?
assert(isa<TemplateTemplateParmDecl>(*OldParm) &&
"Only template template parameters handled here");
TemplateTemplateParmDecl *OldTTP
= cast<TemplateTemplateParmDecl>(*OldParm);
TemplateTemplateParmDecl *NewTTP
= cast<TemplateTemplateParmDecl>(*NewParm);
if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
OldTTP->getTemplateParameters(),
Complain,
/*IsTemplateTemplateParm=*/true,
TemplateArgLoc))
return false;
}
}
return true;
}
/// \brief Check whether a template can be declared within this scope.
///
/// If the template declaration is valid in this scope, returns
/// false. Otherwise, issues a diagnostic and returns true.
bool
Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
// Find the nearest enclosing declaration scope.
while ((S->getFlags() & Scope::DeclScope) == 0 ||
(S->getFlags() & Scope::TemplateParamScope) != 0)
S = S->getParent();
// C++ [temp]p2:
// A template-declaration can appear only as a namespace scope or
// class scope declaration.
DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
if (Ctx && isa<LinkageSpecDecl>(Ctx) &&
cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
<< TemplateParams->getSourceRange();
while (Ctx && isa<LinkageSpecDecl>(Ctx))
Ctx = Ctx->getParent();
if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
return false;
return Diag(TemplateParams->getTemplateLoc(),
diag::err_template_outside_namespace_or_class_scope)
<< TemplateParams->getSourceRange();
}
/// \brief Check whether a class template specialization or explicit
/// instantiation in the current context is well-formed.
///
/// This routine determines whether a class template specialization or
/// explicit instantiation can be declared in the current context
/// (C++ [temp.expl.spec]p2, C++0x [temp.explicit]p2) and emits
/// appropriate diagnostics if there was an error. It returns true if
// there was an error that we cannot recover from, and false otherwise.
bool
Sema::CheckClassTemplateSpecializationScope(ClassTemplateDecl *ClassTemplate,
ClassTemplateSpecializationDecl *PrevDecl,
SourceLocation TemplateNameLoc,
SourceRange ScopeSpecifierRange,
bool PartialSpecialization,
bool ExplicitInstantiation) {
// C++ [temp.expl.spec]p2:
// An explicit specialization shall be declared in the namespace
// of which the template is a member, or, for member templates, in
// the namespace of which the enclosing class or enclosing class
// template is a member. An explicit specialization of a member
// function, member class or static data member of a class
// template shall be declared in the namespace of which the class
// template is a member. Such a declaration may also be a
// definition. If the declaration is not a definition, the
// specialization may be defined later in the name- space in which
// the explicit specialization was declared, or in a namespace
// that encloses the one in which the explicit specialization was
// declared.
if (CurContext->getLookupContext()->isFunctionOrMethod()) {
int Kind = ExplicitInstantiation? 2 : PartialSpecialization? 1 : 0;
Diag(TemplateNameLoc, diag::err_template_spec_decl_function_scope)
<< Kind << ClassTemplate;
return true;
}
DeclContext *DC = CurContext->getEnclosingNamespaceContext();
DeclContext *TemplateContext
= ClassTemplate->getDeclContext()->getEnclosingNamespaceContext();
if ((!PrevDecl || PrevDecl->getSpecializationKind() == TSK_Undeclared) &&
!ExplicitInstantiation) {
// There is no prior declaration of this entity, so this
// specialization must be in the same context as the template
// itself.
if (DC != TemplateContext) {
if (isa<TranslationUnitDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_decl_out_of_scope_global)
<< PartialSpecialization
<< ClassTemplate << ScopeSpecifierRange;
else if (isa<NamespaceDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_decl_out_of_scope)
<< PartialSpecialization << ClassTemplate
<< cast<NamedDecl>(TemplateContext) << ScopeSpecifierRange;
Diag(ClassTemplate->getLocation(), diag::note_template_decl_here);
}
return false;
}
// We have a previous declaration of this entity. Make sure that
// this redeclaration (or definition) occurs in an enclosing namespace.
if (!CurContext->Encloses(TemplateContext)) {
// FIXME: In C++98, we would like to turn these errors into warnings,
// dependent on a -Wc++0x flag.
bool SuppressedDiag = false;
int Kind = ExplicitInstantiation? 2 : PartialSpecialization? 1 : 0;
if (isa<TranslationUnitDecl>(TemplateContext)) {
if (!ExplicitInstantiation || getLangOptions().CPlusPlus0x)
Diag(TemplateNameLoc, diag::err_template_spec_redecl_global_scope)
<< Kind << ClassTemplate << ScopeSpecifierRange;
else
SuppressedDiag = true;
} else if (isa<NamespaceDecl>(TemplateContext)) {
if (!ExplicitInstantiation || getLangOptions().CPlusPlus0x)
Diag(TemplateNameLoc, diag::err_template_spec_redecl_out_of_scope)
<< Kind << ClassTemplate
<< cast<NamedDecl>(TemplateContext) << ScopeSpecifierRange;
else
SuppressedDiag = true;
}
if (!SuppressedDiag)
Diag(ClassTemplate->getLocation(), diag::note_template_decl_here);
}
return false;
}
/// \brief Check the non-type template arguments of a class template
/// partial specialization according to C++ [temp.class.spec]p9.
///
/// \param TemplateParams the template parameters of the primary class
/// template.
///
/// \param TemplateArg the template arguments of the class template
/// partial specialization.
///
/// \param MirrorsPrimaryTemplate will be set true if the class
/// template partial specialization arguments are identical to the
/// implicit template arguments of the primary template. This is not
/// necessarily an error (C++0x), and it is left to the caller to diagnose
/// this condition when it is an error.
///
/// \returns true if there was an error, false otherwise.
bool Sema::CheckClassTemplatePartialSpecializationArgs(
TemplateParameterList *TemplateParams,
const TemplateArgumentListBuilder &TemplateArgs,
bool &MirrorsPrimaryTemplate) {
// FIXME: the interface to this function will have to change to
// accommodate variadic templates.
MirrorsPrimaryTemplate = true;
const TemplateArgument *ArgList = TemplateArgs.getFlatArguments();
for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
// Determine whether the template argument list of the partial
// specialization is identical to the implicit argument list of
// the primary template. The caller may need to diagnostic this as
// an error per C++ [temp.class.spec]p9b3.
if (MirrorsPrimaryTemplate) {
if (TemplateTypeParmDecl *TTP
= dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) {
if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) !=
Context.getCanonicalType(ArgList[I].getAsType()))
MirrorsPrimaryTemplate = false;
} else if (TemplateTemplateParmDecl *TTP
= dyn_cast<TemplateTemplateParmDecl>(
TemplateParams->getParam(I))) {
// FIXME: We should settle on either Declaration storage or
// Expression storage for template template parameters.
TemplateTemplateParmDecl *ArgDecl
= dyn_cast_or_null<TemplateTemplateParmDecl>(
ArgList[I].getAsDecl());
if (!ArgDecl)
if (DeclRefExpr *DRE
= dyn_cast_or_null<DeclRefExpr>(ArgList[I].getAsExpr()))
ArgDecl = dyn_cast<TemplateTemplateParmDecl>(DRE->getDecl());
if (!ArgDecl ||
ArgDecl->getIndex() != TTP->getIndex() ||
ArgDecl->getDepth() != TTP->getDepth())
MirrorsPrimaryTemplate = false;
}
}
NonTypeTemplateParmDecl *Param
= dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
if (!Param) {
continue;
}
Expr *ArgExpr = ArgList[I].getAsExpr();
if (!ArgExpr) {
MirrorsPrimaryTemplate = false;
continue;
}
// C++ [temp.class.spec]p8:
// A non-type argument is non-specialized if it is the name of a
// non-type parameter. All other non-type arguments are
// specialized.
//
// Below, we check the two conditions that only apply to
// specialized non-type arguments, so skip any non-specialized
// arguments.
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) {
if (MirrorsPrimaryTemplate &&
(Param->getIndex() != NTTP->getIndex() ||
Param->getDepth() != NTTP->getDepth()))
MirrorsPrimaryTemplate = false;
continue;
}
// C++ [temp.class.spec]p9:
// Within the argument list of a class template partial
// specialization, the following restrictions apply:
// -- A partially specialized non-type argument expression
// shall not involve a template parameter of the partial
// specialization except when the argument expression is a
// simple identifier.
if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) {
Diag(ArgExpr->getLocStart(),
diag::err_dependent_non_type_arg_in_partial_spec)
<< ArgExpr->getSourceRange();
return true;
}
// -- The type of a template parameter corresponding to a
// specialized non-type argument shall not be dependent on a
// parameter of the specialization.
if (Param->getType()->isDependentType()) {
Diag(ArgExpr->getLocStart(),
diag::err_dependent_typed_non_type_arg_in_partial_spec)
<< Param->getType()
<< ArgExpr->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
MirrorsPrimaryTemplate = false;
}
return false;
}
Sema::DeclResult
Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
TagUseKind TUK,
SourceLocation KWLoc,
const CXXScopeSpec &SS,
TemplateTy TemplateD,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc,
AttributeList *Attr,
MultiTemplateParamsArg TemplateParameterLists) {
assert(TUK == TUK_Declaration || TUK == TUK_Definition);
// Find the class template we're specializing
TemplateName Name = TemplateD.getAsVal<TemplateName>();
ClassTemplateDecl *ClassTemplate
= cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
bool isPartialSpecialization = false;
// Check the validity of the template headers that introduce this
// template.
TemplateParameterList *TemplateParams
= MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS,
(TemplateParameterList**)TemplateParameterLists.get(),
TemplateParameterLists.size());
if (TemplateParams && TemplateParams->size() > 0) {
isPartialSpecialization = true;
// C++ [temp.class.spec]p10:
// The template parameter list of a specialization shall not
// contain default template argument values.
for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
Decl *Param = TemplateParams->getParam(I);
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
if (TTP->hasDefaultArgument()) {
Diag(TTP->getDefaultArgumentLoc(),
diag::err_default_arg_in_partial_spec);
TTP->setDefaultArgument(QualType(), SourceLocation(), false);
}
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(Param)) {
if (Expr *DefArg = NTTP->getDefaultArgument()) {
Diag(NTTP->getDefaultArgumentLoc(),
diag::err_default_arg_in_partial_spec)
<< DefArg->getSourceRange();
NTTP->setDefaultArgument(0);
DefArg->Destroy(Context);
}
} else {
TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
if (Expr *DefArg = TTP->getDefaultArgument()) {
Diag(TTP->getDefaultArgumentLoc(),
diag::err_default_arg_in_partial_spec)
<< DefArg->getSourceRange();
TTP->setDefaultArgument(0);
DefArg->Destroy(Context);
}
}
}
} else if (!TemplateParams)
Diag(KWLoc, diag::err_template_spec_needs_header)
<< CodeModificationHint::CreateInsertion(KWLoc, "template<> ");
// Check that the specialization uses the same tag kind as the
// original template.
TagDecl::TagKind Kind;
switch (TagSpec) {
default: assert(0 && "Unknown tag type!");
case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break;
case DeclSpec::TST_union: Kind = TagDecl::TK_union; break;
case DeclSpec::TST_class: Kind = TagDecl::TK_class; break;
}
if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
Kind, KWLoc,
*ClassTemplate->getIdentifier())) {
Diag(KWLoc, diag::err_use_with_wrong_tag)
<< ClassTemplate
<< CodeModificationHint::CreateReplacement(KWLoc,
ClassTemplate->getTemplatedDecl()->getKindName());
Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
diag::note_previous_use);
Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
}
// Translate the parser's template argument list in our AST format.
llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
translateTemplateArguments(TemplateArgsIn, TemplateArgLocs, TemplateArgs);
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
TemplateArgs.size());
if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, LAngleLoc,
TemplateArgs.data(), TemplateArgs.size(),
RAngleLoc, false, Converted))
return true;
assert((Converted.structuredSize() ==
ClassTemplate->getTemplateParameters()->size()) &&
"Converted template argument list is too short!");
// Find the class template (partial) specialization declaration that
// corresponds to these arguments.
llvm::FoldingSetNodeID ID;
if (isPartialSpecialization) {
bool MirrorsPrimaryTemplate;
if (CheckClassTemplatePartialSpecializationArgs(
ClassTemplate->getTemplateParameters(),
Converted, MirrorsPrimaryTemplate))
return true;
if (MirrorsPrimaryTemplate) {
// C++ [temp.class.spec]p9b3:
//
// -- The argument list of the specialization shall not be identical
// to the implicit argument list of the primary template.
Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
<< (TUK == TUK_Definition)
<< CodeModificationHint::CreateRemoval(SourceRange(LAngleLoc,
RAngleLoc));
return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
ClassTemplate->getIdentifier(),
TemplateNameLoc,
Attr,
TemplateParams,
AS_none);
}
// FIXME: Template parameter list matters, too
ClassTemplatePartialSpecializationDecl::Profile(ID,
Converted.getFlatArguments(),
Converted.flatSize(),
Context);
} else
ClassTemplateSpecializationDecl::Profile(ID,
Converted.getFlatArguments(),
Converted.flatSize(),
Context);
void *InsertPos = 0;
ClassTemplateSpecializationDecl *PrevDecl = 0;
if (isPartialSpecialization)
PrevDecl
= ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID,
InsertPos);
else
PrevDecl
= ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
ClassTemplateSpecializationDecl *Specialization = 0;
// Check whether we can declare a class template specialization in
// the current scope.
if (CheckClassTemplateSpecializationScope(ClassTemplate, PrevDecl,
TemplateNameLoc,
SS.getRange(),
isPartialSpecialization,
/*ExplicitInstantiation=*/false))
return true;
// The canonical type
QualType CanonType;
if (PrevDecl && PrevDecl->getSpecializationKind() == TSK_Undeclared) {
// Since the only prior class template specialization with these
// arguments was referenced but not declared, reuse that
// declaration node as our own, updating its source location to
// reflect our new declaration.
Specialization = PrevDecl;
Specialization->setLocation(TemplateNameLoc);
PrevDecl = 0;
CanonType = Context.getTypeDeclType(Specialization);
} else if (isPartialSpecialization) {
// Build the canonical type that describes the converted template
// arguments of the class template partial specialization.
CanonType = Context.getTemplateSpecializationType(
TemplateName(ClassTemplate),
Converted.getFlatArguments(),
Converted.flatSize());
// Create a new class template partial specialization declaration node.
TemplateParameterList *TemplateParams
= static_cast<TemplateParameterList*>(*TemplateParameterLists.get());
ClassTemplatePartialSpecializationDecl *PrevPartial
= cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
ClassTemplatePartialSpecializationDecl *Partial
= ClassTemplatePartialSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
TemplateParams,
ClassTemplate,
Converted,
PrevPartial);
if (PrevPartial) {
ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial);
ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial);
} else {
ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos);
}
Specialization = Partial;
// Check that all of the template parameters of the class template
// partial specialization are deducible from the template
// arguments. If not, this class template partial specialization
// will never be used.
llvm::SmallVector<bool, 8> DeducibleParams;
DeducibleParams.resize(TemplateParams->size());
MarkDeducedTemplateParameters(Partial->getTemplateArgs(), DeducibleParams);
unsigned NumNonDeducible = 0;
for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I)
if (!DeducibleParams[I])
++NumNonDeducible;
if (NumNonDeducible) {
Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
<< (NumNonDeducible > 1)
<< SourceRange(TemplateNameLoc, RAngleLoc);
for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
if (!DeducibleParams[I]) {
NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
if (Param->getDeclName())
Diag(Param->getLocation(),
diag::note_partial_spec_unused_parameter)
<< Param->getDeclName();
else
Diag(Param->getLocation(),
diag::note_partial_spec_unused_parameter)
<< std::string("<anonymous>");
}
}
}
} else {
// Create a new class template specialization declaration node for
// this explicit specialization.
Specialization
= ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
ClassTemplate,
Converted,
PrevDecl);
if (PrevDecl) {
ClassTemplate->getSpecializations().RemoveNode(PrevDecl);
ClassTemplate->getSpecializations().GetOrInsertNode(Specialization);
} else {
ClassTemplate->getSpecializations().InsertNode(Specialization,
InsertPos);
}
CanonType = Context.getTypeDeclType(Specialization);
}
// Note that this is an explicit specialization.
Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
// Check that this isn't a redefinition of this specialization.
if (TUK == TUK_Definition) {
if (RecordDecl *Def = Specialization->getDefinition(Context)) {
// FIXME: Should also handle explicit specialization after implicit
// instantiation with a special diagnostic.
SourceRange Range(TemplateNameLoc, RAngleLoc);
Diag(TemplateNameLoc, diag::err_redefinition)
<< Context.getTypeDeclType(Specialization) << Range;
Diag(Def->getLocation(), diag::note_previous_definition);
Specialization->setInvalidDecl();
return true;
}
}
// Build the fully-sugared type for this class template
// specialization as the user wrote in the specialization
// itself. This means that we'll pretty-print the type retrieved
// from the specialization's declaration the way that the user
// actually wrote the specialization, rather than formatting the
// name based on the "canonical" representation used to store the
// template arguments in the specialization.
QualType WrittenTy
= Context.getTemplateSpecializationType(Name,
TemplateArgs.data(),
TemplateArgs.size(),
CanonType);
Specialization->setTypeAsWritten(WrittenTy);
TemplateArgsIn.release();
// C++ [temp.expl.spec]p9:
// A template explicit specialization is in the scope of the
// namespace in which the template was defined.
//
// We actually implement this paragraph where we set the semantic
// context (in the creation of the ClassTemplateSpecializationDecl),
// but we also maintain the lexical context where the actual
// definition occurs.
Specialization->setLexicalDeclContext(CurContext);
// We may be starting the definition of this specialization.
if (TUK == TUK_Definition)
Specialization->startDefinition();
// Add the specialization into its lexical context, so that it can
// be seen when iterating through the list of declarations in that
// context. However, specializations are not found by name lookup.
CurContext->addDecl(Specialization);
return DeclPtrTy::make(Specialization);
}
Sema::DeclPtrTy
Sema::ActOnTemplateDeclarator(Scope *S,
MultiTemplateParamsArg TemplateParameterLists,
Declarator &D) {
return HandleDeclarator(S, D, move(TemplateParameterLists), false);
}
Sema::DeclPtrTy
Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
MultiTemplateParamsArg TemplateParameterLists,
Declarator &D) {
assert(getCurFunctionDecl() == 0 && "Function parsing confused");
assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function &&
"Not a function declarator!");
DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun;
if (FTI.hasPrototype) {
// FIXME: Diagnose arguments without names in C.
}
Scope *ParentScope = FnBodyScope->getParent();
DeclPtrTy DP = HandleDeclarator(ParentScope, D,
move(TemplateParameterLists),
/*IsFunctionDefinition=*/true);
if (FunctionTemplateDecl *FunctionTemplate
= dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>()))
return ActOnStartOfFunctionDef(FnBodyScope,
DeclPtrTy::make(FunctionTemplate->getTemplatedDecl()));
if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>()))
return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function));
return DeclPtrTy();
}
// Explicit instantiation of a class template specialization
// FIXME: Implement extern template semantics
Sema::DeclResult
Sema::ActOnExplicitInstantiation(Scope *S,
SourceLocation ExternLoc,
SourceLocation TemplateLoc,
unsigned TagSpec,
SourceLocation KWLoc,
const CXXScopeSpec &SS,
TemplateTy TemplateD,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc,
AttributeList *Attr) {
// Find the class template we're specializing
TemplateName Name = TemplateD.getAsVal<TemplateName>();
ClassTemplateDecl *ClassTemplate
= cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
// Check that the specialization uses the same tag kind as the
// original template.
TagDecl::TagKind Kind;
switch (TagSpec) {
default: assert(0 && "Unknown tag type!");
case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break;
case DeclSpec::TST_union: Kind = TagDecl::TK_union; break;
case DeclSpec::TST_class: Kind = TagDecl::TK_class; break;
}
if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
Kind, KWLoc,
*ClassTemplate->getIdentifier())) {
Diag(KWLoc, diag::err_use_with_wrong_tag)
<< ClassTemplate
<< CodeModificationHint::CreateReplacement(KWLoc,
ClassTemplate->getTemplatedDecl()->getKindName());
Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
diag::note_previous_use);
Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
}
// C++0x [temp.explicit]p2:
// [...] An explicit instantiation shall appear in an enclosing
// namespace of its template. [...]
//
// This is C++ DR 275.
if (CheckClassTemplateSpecializationScope(ClassTemplate, 0,
TemplateNameLoc,
SS.getRange(),
/*PartialSpecialization=*/false,
/*ExplicitInstantiation=*/true))
return true;
// Translate the parser's template argument list in our AST format.
llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
translateTemplateArguments(TemplateArgsIn, TemplateArgLocs, TemplateArgs);
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
TemplateArgs.size());
if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, LAngleLoc,
TemplateArgs.data(), TemplateArgs.size(),
RAngleLoc, false, Converted))
return true;
assert((Converted.structuredSize() ==
ClassTemplate->getTemplateParameters()->size()) &&
"Converted template argument list is too short!");
// Find the class template specialization declaration that
// corresponds to these arguments.
llvm::FoldingSetNodeID ID;
ClassTemplateSpecializationDecl::Profile(ID,
Converted.getFlatArguments(),
Converted.flatSize(),
Context);
void *InsertPos = 0;
ClassTemplateSpecializationDecl *PrevDecl
= ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
ClassTemplateSpecializationDecl *Specialization = 0;
bool SpecializationRequiresInstantiation = true;
if (PrevDecl) {
if (PrevDecl->getSpecializationKind()
== TSK_ExplicitInstantiationDefinition) {
// This particular specialization has already been declared or
// instantiated. We cannot explicitly instantiate it.
Diag(TemplateNameLoc, diag::err_explicit_instantiation_duplicate)
<< Context.getTypeDeclType(PrevDecl);
Diag(PrevDecl->getLocation(),
diag::note_previous_explicit_instantiation);
return DeclPtrTy::make(PrevDecl);
}
if (PrevDecl->getSpecializationKind() == TSK_ExplicitSpecialization) {
// C++ DR 259, C++0x [temp.explicit]p4:
// For a given set of template parameters, if an explicit
// instantiation of a template appears after a declaration of
// an explicit specialization for that template, the explicit
// instantiation has no effect.
if (!getLangOptions().CPlusPlus0x) {
Diag(TemplateNameLoc,
diag::ext_explicit_instantiation_after_specialization)
<< Context.getTypeDeclType(PrevDecl);
Diag(PrevDecl->getLocation(),
diag::note_previous_template_specialization);
}
// Create a new class template specialization declaration node
// for this explicit specialization. This node is only used to
// record the existence of this explicit instantiation for
// accurate reproduction of the source code; we don't actually
// use it for anything, since it is semantically irrelevant.
Specialization
= ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
ClassTemplate,
Converted, 0);
Specialization->setLexicalDeclContext(CurContext);
CurContext->addDecl(Specialization);
return DeclPtrTy::make(Specialization);
}
// If we have already (implicitly) instantiated this
// specialization, there is less work to do.
if (PrevDecl->getSpecializationKind() == TSK_ImplicitInstantiation)
SpecializationRequiresInstantiation = false;
// Since the only prior class template specialization with these
// arguments was referenced but not declared, reuse that
// declaration node as our own, updating its source location to
// reflect our new declaration.
Specialization = PrevDecl;
Specialization->setLocation(TemplateNameLoc);
PrevDecl = 0;
} else {
// Create a new class template specialization declaration node for
// this explicit specialization.
Specialization
= ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
ClassTemplate,
Converted, 0);
ClassTemplate->getSpecializations().InsertNode(Specialization,
InsertPos);
}
// Build the fully-sugared type for this explicit instantiation as
// the user wrote in the explicit instantiation itself. This means
// that we'll pretty-print the type retrieved from the
// specialization's declaration the way that the user actually wrote
// the explicit instantiation, rather than formatting the name based
// on the "canonical" representation used to store the template
// arguments in the specialization.
QualType WrittenTy
= Context.getTemplateSpecializationType(Name,
TemplateArgs.data(),
TemplateArgs.size(),
Context.getTypeDeclType(Specialization));
Specialization->setTypeAsWritten(WrittenTy);
TemplateArgsIn.release();
// Add the explicit instantiation into its lexical context. However,
// since explicit instantiations are never found by name lookup, we
// just put it into the declaration context directly.
Specialization->setLexicalDeclContext(CurContext);
CurContext->addDecl(Specialization);
// C++ [temp.explicit]p3:
// A definition of a class template or class member template
// shall be in scope at the point of the explicit instantiation of
// the class template or class member template.
//
// This check comes when we actually try to perform the
// instantiation.
TemplateSpecializationKind TSK
= ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
: TSK_ExplicitInstantiationDeclaration;
if (SpecializationRequiresInstantiation)
InstantiateClassTemplateSpecialization(Specialization, TSK);
else // Instantiate the members of this class template specialization.
InstantiateClassTemplateSpecializationMembers(TemplateLoc, Specialization,
TSK);
return DeclPtrTy::make(Specialization);
}
// Explicit instantiation of a member class of a class template.
Sema::DeclResult
Sema::ActOnExplicitInstantiation(Scope *S,
SourceLocation ExternLoc,
SourceLocation TemplateLoc,
unsigned TagSpec,
SourceLocation KWLoc,
const CXXScopeSpec &SS,
IdentifierInfo *Name,
SourceLocation NameLoc,
AttributeList *Attr) {
bool Owned = false;
DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference,
KWLoc, SS, Name, NameLoc, Attr, AS_none,
MultiTemplateParamsArg(*this, 0, 0), Owned);
if (!TagD)
return true;
TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>());
if (Tag->isEnum()) {
Diag(TemplateLoc, diag::err_explicit_instantiation_enum)
<< Context.getTypeDeclType(Tag);
return true;
}
if (Tag->isInvalidDecl())
return true;
CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
if (!Pattern) {
Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
<< Context.getTypeDeclType(Record);
Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
return true;
}
// C++0x [temp.explicit]p2:
// [...] An explicit instantiation shall appear in an enclosing
// namespace of its template. [...]
//
// This is C++ DR 275.
if (getLangOptions().CPlusPlus0x) {
// FIXME: In C++98, we would like to turn these errors into warnings,
// dependent on a -Wc++0x flag.
DeclContext *PatternContext
= Pattern->getDeclContext()->getEnclosingNamespaceContext();
if (!CurContext->Encloses(PatternContext)) {
Diag(TemplateLoc, diag::err_explicit_instantiation_out_of_scope)
<< Record << cast<NamedDecl>(PatternContext) << SS.getRange();
Diag(Pattern->getLocation(), diag::note_previous_declaration);
}
}
TemplateSpecializationKind TSK
= ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
: TSK_ExplicitInstantiationDeclaration;
if (!Record->getDefinition(Context)) {
// If the class has a definition, instantiate it (and all of its
// members, recursively).
Pattern = cast_or_null<CXXRecordDecl>(Pattern->getDefinition(Context));
if (Pattern && InstantiateClass(TemplateLoc, Record, Pattern,
getTemplateInstantiationArgs(Record),
TSK))
return true;
} else // Instantiate all of the members of the class.
InstantiateClassMembers(TemplateLoc, Record,
getTemplateInstantiationArgs(Record), TSK);
// FIXME: We don't have any representation for explicit instantiations of
// member classes. Such a representation is not needed for compilation, but it
// should be available for clients that want to see all of the declarations in
// the source code.
return TagD;
}
Sema::TypeResult
Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS,
const IdentifierInfo &II, SourceLocation IdLoc) {
NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
if (!NNS)
return true;
QualType T = CheckTypenameType(NNS, II, SourceRange(TypenameLoc, IdLoc));
if (T.isNull())
return true;
return T.getAsOpaquePtr();
}
Sema::TypeResult
Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS,
SourceLocation TemplateLoc, TypeTy *Ty) {
QualType T = GetTypeFromParser(Ty);
NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
const TemplateSpecializationType *TemplateId
= T->getAsTemplateSpecializationType();
assert(TemplateId && "Expected a template specialization type");
if (computeDeclContext(SS, false)) {
// If we can compute a declaration context, then the "typename"
// keyword was superfluous. Just build a QualifiedNameType to keep
// track of the nested-name-specifier.
// FIXME: Note that the QualifiedNameType had the "typename" keyword!
return Context.getQualifiedNameType(NNS, T).getAsOpaquePtr();
}
return Context.getTypenameType(NNS, TemplateId).getAsOpaquePtr();
}
/// \brief Build the type that describes a C++ typename specifier,
/// e.g., "typename T::type".
QualType
Sema::CheckTypenameType(NestedNameSpecifier *NNS, const IdentifierInfo &II,
SourceRange Range) {
CXXRecordDecl *CurrentInstantiation = 0;
if (NNS->isDependent()) {
CurrentInstantiation = getCurrentInstantiationOf(NNS);
// If the nested-name-specifier does not refer to the current
// instantiation, then build a typename type.
if (!CurrentInstantiation)
return Context.getTypenameType(NNS, &II);
// The nested-name-specifier refers to the current instantiation, so the
// "typename" keyword itself is superfluous. In C++03, the program is
// actually ill-formed. However, DR 382 (in C++0x CD1) allows such
// extraneous "typename" keywords, and we retroactively apply this DR to
// C++03 code.
}
DeclContext *Ctx = 0;
if (CurrentInstantiation)
Ctx = CurrentInstantiation;
else {
CXXScopeSpec SS;
SS.setScopeRep(NNS);
SS.setRange(Range);
if (RequireCompleteDeclContext(SS))
return QualType();
Ctx = computeDeclContext(SS);
}
assert(Ctx && "No declaration context?");
DeclarationName Name(&II);
LookupResult Result = LookupQualifiedName(Ctx, Name, LookupOrdinaryName,
false);
unsigned DiagID = 0;
Decl *Referenced = 0;
switch (Result.getKind()) {
case LookupResult::NotFound:
if (Ctx->isTranslationUnit())
DiagID = diag::err_typename_nested_not_found_global;
else
DiagID = diag::err_typename_nested_not_found;
break;
case LookupResult::Found:
if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getAsDecl())) {
// We found a type. Build a QualifiedNameType, since the
// typename-specifier was just sugar. FIXME: Tell
// QualifiedNameType that it has a "typename" prefix.
return Context.getQualifiedNameType(NNS, Context.getTypeDeclType(Type));
}
DiagID = diag::err_typename_nested_not_type;
Referenced = Result.getAsDecl();
break;
case LookupResult::FoundOverloaded:
DiagID = diag::err_typename_nested_not_type;
Referenced = *Result.begin();
break;
case LookupResult::AmbiguousBaseSubobjectTypes:
case LookupResult::AmbiguousBaseSubobjects:
case LookupResult::AmbiguousReference:
DiagnoseAmbiguousLookup(Result, Name, Range.getEnd(), Range);
return QualType();
}
// If we get here, it's because name lookup did not find a
// type. Emit an appropriate diagnostic and return an error.
if (NamedDecl *NamedCtx = dyn_cast<NamedDecl>(Ctx))
Diag(Range.getEnd(), DiagID) << Range << Name << NamedCtx;
else
Diag(Range.getEnd(), DiagID) << Range << Name;
if (Referenced)
Diag(Referenced->getLocation(), diag::note_typename_refers_here)
<< Name;
return QualType();
}
namespace {
// See Sema::RebuildTypeInCurrentInstantiation
class VISIBILITY_HIDDEN CurrentInstantiationRebuilder
: public TreeTransform<CurrentInstantiationRebuilder>
{
SourceLocation Loc;
DeclarationName Entity;
public:
CurrentInstantiationRebuilder(Sema &SemaRef,
SourceLocation Loc,
DeclarationName Entity)
: TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
Loc(Loc), Entity(Entity) { }
/// \brief Determine whether the given type \p T has already been
/// transformed.
///
/// For the purposes of type reconstruction, a type has already been
/// transformed if it is NULL or if it is not dependent.
bool AlreadyTransformed(QualType T) {
return T.isNull() || !T->isDependentType();
}
/// \brief Returns the location of the entity whose type is being
/// rebuilt.
SourceLocation getBaseLocation() { return Loc; }
/// \brief Returns the name of the entity whose type is being rebuilt.
DeclarationName getBaseEntity() { return Entity; }
/// \brief Transforms an expression by returning the expression itself
/// (an identity function).
///
/// FIXME: This is completely unsafe; we will need to actually clone the
/// expressions.
Sema::OwningExprResult TransformExpr(Expr *E) {
return getSema().Owned(E);
}
/// \brief Transforms a typename type by determining whether the type now
/// refers to a member of the current instantiation, and then
/// type-checking and building a QualifiedNameType (when possible).
QualType TransformTypenameType(const TypenameType *T);
};
}
QualType
CurrentInstantiationRebuilder::TransformTypenameType(const TypenameType *T) {
NestedNameSpecifier *NNS
= TransformNestedNameSpecifier(T->getQualifier(),
/*FIXME:*/SourceRange(getBaseLocation()));
if (!NNS)
return QualType();
// If the nested-name-specifier did not change, and we cannot compute the
// context corresponding to the nested-name-specifier, then this
// typename type will not change; exit early.
CXXScopeSpec SS;
SS.setRange(SourceRange(getBaseLocation()));
SS.setScopeRep(NNS);
if (NNS == T->getQualifier() && getSema().computeDeclContext(SS) == 0)
return QualType(T, 0);
// Rebuild the typename type, which will probably turn into a
// QualifiedNameType.
if (const TemplateSpecializationType *TemplateId = T->getTemplateId()) {
QualType NewTemplateId
= TransformType(QualType(TemplateId, 0));
if (NewTemplateId.isNull())
return QualType();
if (NNS == T->getQualifier() &&
NewTemplateId == QualType(TemplateId, 0))
return QualType(T, 0);
return getDerived().RebuildTypenameType(NNS, NewTemplateId);
}
return getDerived().RebuildTypenameType(NNS, T->getIdentifier());
}
/// \brief Rebuilds a type within the context of the current instantiation.
///
/// The type \p T is part of the type of an out-of-line member definition of
/// a class template (or class template partial specialization) that was parsed
/// and constructed before we entered the scope of the class template (or
/// partial specialization thereof). This routine will rebuild that type now
/// that we have entered the declarator's scope, which may produce different
/// canonical types, e.g.,
///
/// \code
/// template<typename T>
/// struct X {
/// typedef T* pointer;
/// pointer data();
/// };
///
/// template<typename T>
/// typename X<T>::pointer X<T>::data() { ... }
/// \endcode
///
/// Here, the type "typename X<T>::pointer" will be created as a TypenameType,
/// since we do not know that we can look into X<T> when we parsed the type.
/// This function will rebuild the type, performing the lookup of "pointer"
/// in X<T> and returning a QualifiedNameType whose canonical type is the same
/// as the canonical type of T*, allowing the return types of the out-of-line
/// definition and the declaration to match.
QualType Sema::RebuildTypeInCurrentInstantiation(QualType T, SourceLocation Loc,
DeclarationName Name) {
if (T.isNull() || !T->isDependentType())
return T;
CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
return Rebuilder.TransformType(T);
}
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