//===------- 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 "Lookup.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/Parse/Template.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "llvm/ADT/StringExtras.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->getDeclContext());
if (Record->getDescribedClassTemplate())
return Record->getDescribedClassTemplate();
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(Record))
return Spec->getSpecializedTemplate();
}
return 0;
}
return 0;
}
static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) {
LookupResult::Filter filter = R.makeFilter();
while (filter.hasNext()) {
NamedDecl *Orig = filter.next();
NamedDecl *Repl = isAcceptableTemplateName(C, Orig->getUnderlyingDecl());
if (!Repl)
filter.erase();
else if (Repl != Orig)
filter.replace(Repl);
}
filter.done();
}
TemplateNameKind Sema::isTemplateName(Scope *S,
const CXXScopeSpec &SS,
UnqualifiedId &Name,
TypeTy *ObjectTypePtr,
bool EnteringContext,
TemplateTy &TemplateResult) {
DeclarationName TName;
switch (Name.getKind()) {
case UnqualifiedId::IK_Identifier:
TName = DeclarationName(Name.Identifier);
break;
case UnqualifiedId::IK_OperatorFunctionId:
TName = Context.DeclarationNames.getCXXOperatorName(
Name.OperatorFunctionId.Operator);
break;
case UnqualifiedId::IK_LiteralOperatorId:
TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
break;
default:
return TNK_Non_template;
}
QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr);
LookupResult R(*this, TName, SourceLocation(), LookupOrdinaryName);
R.suppressDiagnostics();
LookupTemplateName(R, S, SS, ObjectType, EnteringContext);
if (R.empty())
return TNK_Non_template;
TemplateName Template;
TemplateNameKind TemplateKind;
unsigned ResultCount = R.end() - R.begin();
if (ResultCount > 1) {
// We assume that we'll preserve the qualifier from a function
// template name in other ways.
Template = Context.getOverloadedTemplateName(R.begin(), R.end());
TemplateKind = TNK_Function_template;
} else {
TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
if (SS.isSet() && !SS.isInvalid()) {
NestedNameSpecifier *Qualifier
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
Template = Context.getQualifiedTemplateName(Qualifier, false, TD);
} else {
Template = TemplateName(TD);
}
if (isa<FunctionTemplateDecl>(TD))
TemplateKind = TNK_Function_template;
else {
assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD));
TemplateKind = TNK_Type_template;
}
}
TemplateResult = TemplateTy::make(Template);
return TemplateKind;
}
void Sema::LookupTemplateName(LookupResult &Found,
Scope *S, const CXXScopeSpec &SS,
QualType ObjectType,
bool EnteringContext) {
// Determine where to perform name lookup
DeclContext *LookupCtx = 0;
bool isDependent = false;
if (!ObjectType.isNull()) {
// This nested-name-specifier occurs in a member access expression, e.g.,
// x->B::f, and we are looking into the type of the object.
assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
LookupCtx = computeDeclContext(ObjectType);
isDependent = ObjectType->isDependentType();
assert((isDependent || !ObjectType->isIncompleteType()) &&
"Caller should have completed object type");
} else if (SS.isSet()) {
// This nested-name-specifier occurs after another nested-name-specifier,
// so long into the context associated with the prior nested-name-specifier.
LookupCtx = computeDeclContext(SS, EnteringContext);
isDependent = isDependentScopeSpecifier(SS);
// The declaration context must be complete.
if (LookupCtx && RequireCompleteDeclContext(SS))
return;
}
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.
LookupQualifiedName(Found, LookupCtx);
if (!ObjectType.isNull() && Found.empty()) {
// 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...
if (S) LookupName(Found, S);
ObjectTypeSearchedInScope = true;
}
} else if (isDependent) {
// We cannot look into a dependent object type or
return;
} else {
// Perform unqualified name lookup in the current scope.
LookupName(Found, S);
}
// FIXME: Cope with ambiguous name-lookup results.
assert(!Found.isAmbiguous() &&
"Cannot handle template name-lookup ambiguities");
FilterAcceptableTemplateNames(Context, Found);
if (Found.empty())
return;
if (S && !ObjectType.isNull() && !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(*this, Found.getLookupName(), Found.getNameLoc(),
LookupOrdinaryName);
LookupName(FoundOuter, S);
FilterAcceptableTemplateNames(Context, FoundOuter);
// FIXME: Handle ambiguities in this lookup better
if (FoundOuter.empty()) {
// - if the name is not found, the name found in the class of the
// object expression is used, otherwise
} else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) {
// - 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 (!Found.isSingleResult() ||
Found.getFoundDecl()->getCanonicalDecl()
!= FoundOuter.getFoundDecl()->getCanonicalDecl()) {
Diag(Found.getNameLoc(),
diag::err_nested_name_member_ref_lookup_ambiguous)
<< Found.getLookupName();
Diag(Found.getRepresentativeDecl()->getLocation(),
diag::note_ambig_member_ref_object_type)
<< ObjectType;
Diag(FoundOuter.getFoundDecl()->getLocation(),
diag::note_ambig_member_ref_scope);
// Recover by taking the template that we found in the object
// expression's type.
}
}
}
}
/// ActOnDependentIdExpression - Handle a dependent id-expression that
/// was just parsed. This is only possible with an explicit scope
/// specifier naming a dependent type.
Sema::OwningExprResult
Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
DeclarationName Name,
SourceLocation NameLoc,
bool isAddressOfOperand,
const TemplateArgumentListInfo *TemplateArgs) {
NestedNameSpecifier *Qualifier
= static_cast<NestedNameSpecifier*>(SS.getScopeRep());
if (!isAddressOfOperand &&
isa<CXXMethodDecl>(CurContext) &&
cast<CXXMethodDecl>(CurContext)->isInstance()) {
QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context);
// Since the 'this' expression is synthesized, we don't need to
// perform the double-lookup check.
NamedDecl *FirstQualifierInScope = 0;
return Owned(CXXDependentScopeMemberExpr::Create(Context,
/*This*/ 0, ThisType,
/*IsArrow*/ true,
/*Op*/ SourceLocation(),
Qualifier, SS.getRange(),
FirstQualifierInScope,
Name, NameLoc,
TemplateArgs));
}
return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs);
}
Sema::OwningExprResult
Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
DeclarationName Name,
SourceLocation NameLoc,
const TemplateArgumentListInfo *TemplateArgs) {
return Owned(DependentScopeDeclRefExpr::Create(Context,
static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
SS.getRange(),
Name, NameLoc,
TemplateArgs));
}
/// 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_or_null<TemplateDecl>(D.getAs<Decl>())) {
D = DeclPtrTy::make(Temp->getTemplatedDecl());
return Temp;
}
return 0;
}
static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
const ParsedTemplateArgument &Arg) {
switch (Arg.getKind()) {
case ParsedTemplateArgument::Type: {
TypeSourceInfo *DI;
QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
if (!DI)
DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
return TemplateArgumentLoc(TemplateArgument(T), DI);
}
case ParsedTemplateArgument::NonType: {
Expr *E = static_cast<Expr *>(Arg.getAsExpr());
return TemplateArgumentLoc(TemplateArgument(E), E);
}
case ParsedTemplateArgument::Template: {
TemplateName Template
= TemplateName::getFromVoidPointer(Arg.getAsTemplate().get());
return TemplateArgumentLoc(TemplateArgument(Template),
Arg.getScopeSpec().getRange(),
Arg.getLocation());
}
}
llvm_unreachable("Unhandled parsed template argument");
return TemplateArgumentLoc();
}
/// \brief Translates template arguments as provided by the parser
/// into template arguments used by semantic analysis.
void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
TemplateArgumentListInfo &TemplateArgs) {
for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
TemplateArgs.addArgument(translateTemplateArgument(*this,
TemplateArgsIn[I]));
}
/// 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 = LookupSingleName(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>());
TypeSourceInfo *DefaultTInfo;
GetTypeFromParser(DefaultT, &DefaultTInfo);
assert(DefaultTInfo && "expected source information for type");
// 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, DefaultTInfo)) {
Parm->setInvalidDecl();
return;
}
Parm->setDefaultArgument(DefaultTInfo, 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) {
TypeSourceInfo *TInfo = 0;
QualType T = GetTypeForDeclarator(D, S, &TInfo);
assert(S->isTemplateParamScope() &&
"Non-type template parameter not in template parameter scope!");
bool Invalid = false;
IdentifierInfo *ParamName = D.getIdentifier();
if (ParamName) {
NamedDecl *PrevDecl = LookupSingleName(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, TInfo);
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,
const ParsedTemplateArgument &Default) {
TemplateTemplateParmDecl *TemplateParm
= cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>());
// 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 only that we have a template template argument. We don't want to
// try to check well-formedness now, because our template template parameter
// might have dependent types in its template parameters, which we wouldn't
// be able to match now.
//
// If none of the template template parameter's template arguments mention
// other template parameters, we could actually perform more checking here.
// However, it isn't worth doing.
TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
if (DefaultArg.getArgument().getAsTemplate().isNull()) {
Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
<< DefaultArg.getSourceRange();
return;
}
TemplateParm->setDefaultArgument(DefaultArg);
}
/// 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::warn_template_export_unsupported);
return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
(NamedDecl**)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 = TagDecl::getTagKindForTypeSpec(TagSpec);
assert(Kind != TagDecl::TK_enum && "can't build template of enumerated type");
// 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(*this, Name, NameLoc, LookupOrdinaryName,
ForRedeclaration);
if (SS.isNotEmpty() && !SS.isInvalid()) {
if (RequireCompleteDeclContext(SS))
return true;
SemanticContext = computeDeclContext(SS, true);
if (!SemanticContext) {
// FIXME: Produce a reasonable diagnostic here
return true;
}
LookupQualifiedName(Previous, SemanticContext);
} else {
SemanticContext = CurContext;
LookupName(Previous, S);
}
assert(!Previous.isAmbiguous() && "Ambiguity in class template redecl?");
NamedDecl *PrevDecl = 0;
if (Previous.begin() != Previous.end())
PrevDecl = *Previous.begin();
if (PrevDecl && TUK == TUK_Friend) {
// C++ [namespace.memdef]p3:
// [...] When looking for a prior declaration of a class or a function
// declared as a friend, and when the name of the friend class or
// function is neither a qualified name nor a template-id, scopes outside
// the innermost enclosing namespace scope are not considered.
DeclContext *OutermostContext = CurContext;
while (!OutermostContext->isFileContext())
OutermostContext = OutermostContext->getLookupParent();
if (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
OutermostContext->Encloses(PrevDecl->getDeclContext())) {
SemanticContext = PrevDecl->getDeclContext();
} else {
// Declarations in outer scopes don't matter. However, the outermost
// context we computed is the semantic context for our new
// declaration.
PrevDecl = 0;
SemanticContext = OutermostContext;
}
if (CurContext->isDependentContext()) {
// If this is a dependent context, we don't want to link the friend
// class template to the template in scope, because that would perform
// checking of the template parameter lists that can't be performed
// until the outer context is instantiated.
PrevDecl = 0;
}
} else 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);
// We may have found the injected-class-name of a class template,
// class template partial specialization, or class template specialization.
// In these cases, grab the template that is being defined or specialized.
if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
PrevClassTemplate
= cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
PrevClassTemplate
= cast<ClassTemplateSpecializationDecl>(PrevDecl)
->getSpecializedTemplate();
}
}
if (PrevClassTemplate) {
// Ensure that the template parameter lists are compatible.
if (!TemplateParameterListsAreEqual(TemplateParams,
PrevClassTemplate->getTemplateParameters(),
/*Complain=*/true,
TPL_TemplateMatch))
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,
TPC_ClassTemplate))
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;
// If we are providing an explicit specialization of a member that is a
// class template, make a note of that.
if (PrevClassTemplate &&
PrevClassTemplate->getInstantiatedFromMemberTemplate())
PrevClassTemplate->setMemberSpecialization();
// Set the access specifier.
if (!Invalid && TUK != TUK_Friend)
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);
if (TUK != TUK_Friend)
PushOnScopeChains(NewTemplate, S);
else {
if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
NewTemplate->setAccess(PrevClassTemplate->getAccess());
NewClass->setAccess(PrevClassTemplate->getAccess());
}
NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */
PrevClassTemplate != NULL);
// Friend templates are visible in fairly strange ways.
if (!CurContext->isDependentContext()) {
DeclContext *DC = SemanticContext->getLookupContext();
DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false);
if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
PushOnScopeChains(NewTemplate, EnclosingScope,
/* AddToContext = */ false);
}
FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
NewClass->getLocation(),
NewTemplate,
/*FIXME:*/NewClass->getLocation());
Friend->setAccess(AS_public);
CurContext->addDecl(Friend);
}
if (Invalid) {
NewTemplate->setInvalidDecl();
NewClass->setInvalidDecl();
}
return DeclPtrTy::make(NewTemplate);
}
/// \brief Diagnose the presence of a default template argument on a
/// template parameter, which is ill-formed in certain contexts.
///
/// \returns true if the default template argument should be dropped.
static bool DiagnoseDefaultTemplateArgument(Sema &S,
Sema::TemplateParamListContext TPC,
SourceLocation ParamLoc,
SourceRange DefArgRange) {
switch (TPC) {
case Sema::TPC_ClassTemplate:
return false;
case Sema::TPC_FunctionTemplate:
// C++ [temp.param]p9:
// A default template-argument shall not be specified in a
// function template declaration or a function template
// definition [...]
// (This sentence is not in C++0x, per DR226).
if (!S.getLangOptions().CPlusPlus0x)
S.Diag(ParamLoc,
diag::err_template_parameter_default_in_function_template)
<< DefArgRange;
return false;
case Sema::TPC_ClassTemplateMember:
// C++0x [temp.param]p9:
// A default template-argument shall not be specified in the
// template-parameter-lists of the definition of a member of a
// class template that appears outside of the member's class.
S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
<< DefArgRange;
return true;
case Sema::TPC_FriendFunctionTemplate:
// C++ [temp.param]p9:
// A default template-argument shall not be specified in a
// friend template declaration.
S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
<< DefArgRange;
return true;
// FIXME: C++0x [temp.param]p9 allows default template-arguments
// for friend function templates if there is only a single
// declaration (and it is a definition). Strange!
}
return false;
}
/// \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.
///
/// \param TPC Describes the context in which we are checking the given
/// template parameter list.
///
/// \returns true if an error occurred, false otherwise.
bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
TemplateParameterList *OldParams,
TemplateParamListContext TPC) {
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;
}
if (TemplateTypeParmDecl *NewTypeParm
= dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
// Check the presence of a default argument here.
if (NewTypeParm->hasDefaultArgument() &&
DiagnoseDefaultTemplateArgument(*this, TPC,
NewTypeParm->getLocation(),
NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
.getFullSourceRange()))
NewTypeParm->removeDefaultArgument();
// Merge default arguments for template type parameters.
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->getDefaultArgumentInfo(),
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)) {
// Check the presence of a default argument here.
if (NewNonTypeParm->hasDefaultArgument() &&
DiagnoseDefaultTemplateArgument(*this, TPC,
NewNonTypeParm->getLocation(),
NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
NewNonTypeParm->getDefaultArgument()->Destroy(Context);
NewNonTypeParm->setDefaultArgument(0);
}
// 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 {
// Check the presence of a default argument here.
TemplateTemplateParmDecl *NewTemplateParm
= cast<TemplateTemplateParmDecl>(*NewParam);
if (NewTemplateParm->hasDefaultArgument() &&
DiagnoseDefaultTemplateArgument(*this, TPC,
NewTemplateParm->getLocation(),
NewTemplateParm->getDefaultArgument().getSourceRange()))
NewTemplateParm->setDefaultArgument(TemplateArgumentLoc());
// Merge default arguments for template template parameters
TemplateTemplateParmDecl *OldTemplateParm
= OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
NewTemplateParm->hasDefaultArgument()) {
OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
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->getDefaultArgument().getLocation();
} else if (NewTemplateParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc
= NewTemplateParm->getDefaultArgument().getLocation();
} 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.
///
/// \param IsExplicitSpecialization will be set true if the entity being
/// declared is an explicit specialization, false otherwise.
///
/// \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,
bool &IsExplicitSpecialization) {
IsExplicitSpecialization = false;
// 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;
llvm::SmallVector<ClassTemplateSpecializationDecl *, 4>
ExplicitSpecializationsInSpecifier;
for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
NNS; NNS = NNS->getPrefix()) {
const Type *T = NNS->getAsType();
if (!T) break;
// C++0x [temp.expl.spec]p17:
// A member or a member template may be nested within many
// enclosing class templates. In an explicit specialization for
// such a member, the member declaration shall be preceded by a
// template<> for each enclosing class template that is
// explicitly specialized.
// We interpret this as forbidding typedefs of template
// specializations in the scope specifiers of out-of-line decls.
if (const TypedefType *TT = dyn_cast<TypedefType>(T)) {
const Type *UnderlyingT = TT->LookThroughTypedefs().getTypePtr();
if (isa<TemplateSpecializationType>(UnderlyingT))
// FIXME: better source location information.
Diag(DeclStartLoc, diag::err_typedef_in_def_scope) << QualType(T,0);
T = UnderlyingT;
}
if (const TemplateSpecializationType *SpecType
= dyn_cast<TemplateSpecializationType>(T)) {
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.
if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) {
ExplicitSpecializationsInSpecifier.push_back(SpecDecl);
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<> ");
IsExplicitSpecialization = true;
}
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, TPL_TemplateMatch);
}
CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember);
} else if (ParamLists[Idx]->size() > 0)
Diag(ParamLists[Idx]->getTemplateLoc(),
diag::err_template_param_list_matches_nontemplate)
<< TemplateId
<< ParamLists[Idx]->getSourceRange();
else
IsExplicitSpecialization = true;
}
// 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) {
bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0;
Diag(ParamLists[Idx]->getTemplateLoc(),
isExplicitSpecHeader? diag::warn_template_spec_extra_headers
: diag::err_template_spec_extra_headers)
<< SourceRange(ParamLists[Idx]->getTemplateLoc(),
ParamLists[Idx]->getRAngleLoc());
if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) {
Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(),
diag::note_explicit_template_spec_does_not_need_header)
<< ExplicitSpecializationsInSpecifier.back();
ExplicitSpecializationsInSpecifier.pop_back();
}
++Idx;
}
}
// Return the last template parameter list, which corresponds to the
// entity being declared.
return ParamLists[NumParamLists - 1];
}
QualType Sema::CheckTemplateIdType(TemplateName Name,
SourceLocation TemplateLoc,
const TemplateArgumentListInfo &TemplateArgs) {
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);
}
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(Template->getTemplateParameters(),
TemplateArgs.size());
if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
false, Converted))
return QualType();
assert((Converted.structuredSize() ==
Template->getTemplateParameters()->size()) &&
"Converted template argument list is too short!");
QualType CanonType;
if (Name.isDependent() ||
TemplateSpecializationType::anyDependentTemplateArguments(
TemplateArgs)) {
// 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 TemplateSpecializationType 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(),
ClassTemplate->getLocation(),
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.
return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
}
Action::TypeResult
Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgsIn,
SourceLocation RAngleLoc) {
TemplateName Template = TemplateD.getAsVal<TemplateName>();
// Translate the parser's template argument list in our AST format.
TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
translateTemplateArguments(TemplateArgsIn, TemplateArgs);
QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
TemplateArgsIn.release();
if (Result.isNull())
return true;
TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result);
TemplateSpecializationTypeLoc TL
= cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
TL.setTemplateNameLoc(TemplateLoc);
TL.setLAngleLoc(LAngleLoc);
TL.setRAngleLoc(RAngleLoc);
for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
return CreateLocInfoType(Result, DI).getAsOpaquePtr();
}
Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
TagUseKind TUK,
DeclSpec::TST TagSpec,
SourceLocation TagLoc) {
if (TypeResult.isInvalid())
return Sema::TypeResult();
// FIXME: preserve source info, ideally without copying the DI.
TypeSourceInfo *DI;
QualType Type = GetTypeFromParser(TypeResult.get(), &DI);
// 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)
<< Type
<< CodeModificationHint::CreateReplacement(SourceRange(TagLoc),
D->getKindName());
Diag(D->getLocation(), diag::note_previous_use);
}
}
QualType ElabType = Context.getElaboratedType(Type, TagKind);
return ElabType.getAsOpaquePtr();
}
Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
LookupResult &R,
bool RequiresADL,
const TemplateArgumentListInfo &TemplateArgs) {
// 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.
// These should be filtered out by our callers.
assert(!R.empty() && "empty lookup results when building templateid");
assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
NestedNameSpecifier *Qualifier = 0;
SourceRange QualifierRange;
if (SS.isSet()) {
Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
QualifierRange = SS.getRange();
}
bool Dependent
= UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(),
&TemplateArgs);
UnresolvedLookupExpr *ULE
= UnresolvedLookupExpr::Create(Context, Dependent,
Qualifier, QualifierRange,
R.getLookupName(), R.getNameLoc(),
RequiresADL, TemplateArgs);
for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
ULE->addDecl(*I);
return Owned(ULE);
}
// We actually only call this from template instantiation.
Sema::OwningExprResult
Sema::BuildQualifiedTemplateIdExpr(const CXXScopeSpec &SS,
DeclarationName Name,
SourceLocation NameLoc,
const TemplateArgumentListInfo &TemplateArgs) {
DeclContext *DC;
if (!(DC = computeDeclContext(SS, false)) ||
DC->isDependentContext() ||
RequireCompleteDeclContext(SS))
return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs);
LookupResult R(*this, Name, NameLoc, LookupOrdinaryName);
LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false);
if (R.isAmbiguous())
return ExprError();
if (R.empty()) {
Diag(NameLoc, diag::err_template_kw_refers_to_non_template)
<< Name << SS.getRange();
return ExprError();
}
if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
Diag(NameLoc, diag::err_template_kw_refers_to_class_template)
<< (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange();
Diag(Temp->getLocation(), diag::note_referenced_class_template);
return ExprError();
}
return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs);
}
/// \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 CXXScopeSpec &SS,
UnqualifiedId &Name,
TypeTy *ObjectType,
bool EnteringContext) {
if ((ObjectType &&
computeDeclContext(QualType::getFromOpaquePtr(ObjectType))) ||
(SS.isSet() && computeDeclContext(SS, EnteringContext))) {
// 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, SS, Name, ObjectType,
EnteringContext, Template);
if (TNK == TNK_Non_template) {
Diag(Name.getSourceRange().getBegin(),
diag::err_template_kw_refers_to_non_template)
<< GetNameFromUnqualifiedId(Name)
<< Name.getSourceRange();
return TemplateTy();
}
return Template;
}
NestedNameSpecifier *Qualifier
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
switch (Name.getKind()) {
case UnqualifiedId::IK_Identifier:
return TemplateTy::make(Context.getDependentTemplateName(Qualifier,
Name.Identifier));
case UnqualifiedId::IK_OperatorFunctionId:
return TemplateTy::make(Context.getDependentTemplateName(Qualifier,
Name.OperatorFunctionId.Operator));
case UnqualifiedId::IK_LiteralOperatorId:
assert(false && "We don't support these; Parse shouldn't have allowed propagation");
default:
break;
}
Diag(Name.getSourceRange().getBegin(),
diag::err_template_kw_refers_to_non_template)
<< GetNameFromUnqualifiedId(Name)
<< Name.getSourceRange();
return TemplateTy();
}
bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
const TemplateArgumentLoc &AL,
TemplateArgumentListBuilder &Converted) {
const TemplateArgument &Arg = AL.getArgument();
// 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.
SourceRange SR = AL.getSourceRange();
Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
if (CheckTemplateArgument(Param, AL.getTypeSourceInfo()))
return true;
// Add the converted template type argument.
Converted.Append(
TemplateArgument(Context.getCanonicalType(Arg.getAsType())));
return false;
}
/// \brief Substitute template arguments into the default template argument for
/// the given template type parameter.
///
/// \param SemaRef the semantic analysis object for which we are performing
/// the substitution.
///
/// \param Template the template that we are synthesizing template arguments
/// for.
///
/// \param TemplateLoc the location of the template name that started the
/// template-id we are checking.
///
/// \param RAngleLoc the location of the right angle bracket ('>') that
/// terminates the template-id.
///
/// \param Param the template template parameter whose default we are
/// substituting into.
///
/// \param Converted the list of template arguments provided for template
/// parameters that precede \p Param in the template parameter list.
///
/// \returns the substituted template argument, or NULL if an error occurred.
static TypeSourceInfo *
SubstDefaultTemplateArgument(Sema &SemaRef,
TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation RAngleLoc,
TemplateTypeParmDecl *Param,
TemplateArgumentListBuilder &Converted) {
TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
// If the argument type is dependent, instantiate it now based
// on the previously-computed template arguments.
if (ArgType->getType()->isDependentType()) {
TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
/*TakeArgs=*/false);
MultiLevelTemplateArgumentList AllTemplateArgs
= SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
Param->getDefaultArgumentLoc(),
Param->getDeclName());
}
return ArgType;
}
/// \brief Substitute template arguments into the default template argument for
/// the given non-type template parameter.
///
/// \param SemaRef the semantic analysis object for which we are performing
/// the substitution.
///
/// \param Template the template that we are synthesizing template arguments
/// for.
///
/// \param TemplateLoc the location of the template name that started the
/// template-id we are checking.
///
/// \param RAngleLoc the location of the right angle bracket ('>') that
/// terminates the template-id.
///
/// \param Param the non-type template parameter whose default we are
/// substituting into.
///
/// \param Converted the list of template arguments provided for template
/// parameters that precede \p Param in the template parameter list.
///
/// \returns the substituted template argument, or NULL if an error occurred.
static Sema::OwningExprResult
SubstDefaultTemplateArgument(Sema &SemaRef,
TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation RAngleLoc,
NonTypeTemplateParmDecl *Param,
TemplateArgumentListBuilder &Converted) {
TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
/*TakeArgs=*/false);
MultiLevelTemplateArgumentList AllTemplateArgs
= SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs);
}
/// \brief Substitute template arguments into the default template argument for
/// the given template template parameter.
///
/// \param SemaRef the semantic analysis object for which we are performing
/// the substitution.
///
/// \param Template the template that we are synthesizing template arguments
/// for.
///
/// \param TemplateLoc the location of the template name that started the
/// template-id we are checking.
///
/// \param RAngleLoc the location of the right angle bracket ('>') that
/// terminates the template-id.
///
/// \param Param the template template parameter whose default we are
/// substituting into.
///
/// \param Converted the list of template arguments provided for template
/// parameters that precede \p Param in the template parameter list.
///
/// \returns the substituted template argument, or NULL if an error occurred.
static TemplateName
SubstDefaultTemplateArgument(Sema &SemaRef,
TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation RAngleLoc,
TemplateTemplateParmDecl *Param,
TemplateArgumentListBuilder &Converted) {
TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
/*TakeArgs=*/false);
MultiLevelTemplateArgumentList AllTemplateArgs
= SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
Template, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
return SemaRef.SubstTemplateName(
Param->getDefaultArgument().getArgument().getAsTemplate(),
Param->getDefaultArgument().getTemplateNameLoc(),
AllTemplateArgs);
}
/// \brief If the given template parameter has a default template
/// argument, substitute into that default template argument and
/// return the corresponding template argument.
TemplateArgumentLoc
Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation RAngleLoc,
Decl *Param,
TemplateArgumentListBuilder &Converted) {
if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
if (!TypeParm->hasDefaultArgument())
return TemplateArgumentLoc();
TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
TemplateLoc,
RAngleLoc,
TypeParm,
Converted);
if (DI)
return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
return TemplateArgumentLoc();
}
if (NonTypeTemplateParmDecl *NonTypeParm
= dyn_cast<NonTypeTemplateParmDecl>(Param)) {
if (!NonTypeParm->hasDefaultArgument())
return TemplateArgumentLoc();
OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
TemplateLoc,
RAngleLoc,
NonTypeParm,
Converted);
if (Arg.isInvalid())
return TemplateArgumentLoc();
Expr *ArgE = Arg.takeAs<Expr>();
return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
}
TemplateTemplateParmDecl *TempTempParm
= cast<TemplateTemplateParmDecl>(Param);
if (!TempTempParm->hasDefaultArgument())
return TemplateArgumentLoc();
TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
TemplateLoc,
RAngleLoc,
TempTempParm,
Converted);
if (TName.isNull())
return TemplateArgumentLoc();
return TemplateArgumentLoc(TemplateArgument(TName),
TempTempParm->getDefaultArgument().getTemplateQualifierRange(),
TempTempParm->getDefaultArgument().getTemplateNameLoc());
}
/// \brief Check that the given template argument corresponds to the given
/// template parameter.
bool Sema::CheckTemplateArgument(NamedDecl *Param,
const TemplateArgumentLoc &Arg,
TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation RAngleLoc,
TemplateArgumentListBuilder &Converted) {
// Check template type parameters.
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
return CheckTemplateTypeArgument(TTP, Arg, Converted);
// Check non-type template parameters.
if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
// 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,
NTTP, 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())
return true;
}
switch (Arg.getArgument().getKind()) {
case TemplateArgument::Null:
assert(false && "Should never see a NULL template argument here");
return true;
case TemplateArgument::Expression: {
Expr *E = Arg.getArgument().getAsExpr();
TemplateArgument Result;
if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
return true;
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.getArgument());
break;
case TemplateArgument::Template:
// We were given a template template argument. It may not be ill-formed;
// see below.
if (DependentTemplateName *DTN
= Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) {
// We have a template argument such as \c T::template X, which we
// parsed as a template template argument. However, since we now
// know that we need a non-type template argument, convert this
// template name into an expression.
Expr *E = DependentScopeDeclRefExpr::Create(Context,
DTN->getQualifier(),
Arg.getTemplateQualifierRange(),
DTN->getIdentifier(),
Arg.getTemplateNameLoc());
TemplateArgument Result;
if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
return true;
Converted.Append(Result);
break;
}
// We have a template argument that actually does refer to a class
// template, template alias, or template template parameter, and
// therefore cannot be a non-type template argument.
Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
<< Arg.getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
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.
QualType T = Arg.getArgument().getAsType();
SourceRange SR = Arg.getSourceRange();
if (T->isFunctionType())
Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
else
Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
case TemplateArgument::Pack:
llvm_unreachable("Caller must expand template argument packs");
break;
}
return false;
}
// Check template template parameters.
TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
// Substitute into the template parameter list of the template
// template parameter, since previously-supplied template arguments
// may appear within the template template parameter.
{
// Set up a template instantiation context.
LocalInstantiationScope Scope(*this);
InstantiatingTemplate Inst(*this, TemplateLoc, Template,
TempParm, Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
TemplateArgumentList TemplateArgs(Context, Converted,
/*TakeArgs=*/false);
TempParm = cast_or_null<TemplateTemplateParmDecl>(
SubstDecl(TempParm, CurContext,
MultiLevelTemplateArgumentList(TemplateArgs)));
if (!TempParm)
return true;
// FIXME: TempParam is leaked.
}
switch (Arg.getArgument().getKind()) {
case TemplateArgument::Null:
assert(false && "Should never see a NULL template argument here");
return true;
case TemplateArgument::Template:
if (CheckTemplateArgument(TempParm, Arg))
return true;
Converted.Append(Arg.getArgument());
break;
case TemplateArgument::Expression:
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);
return true;
case TemplateArgument::Declaration:
llvm_unreachable(
"Declaration argument with template template parameter");
break;
case TemplateArgument::Integral:
llvm_unreachable(
"Integral argument with template template parameter");
break;
case TemplateArgument::Pack:
llvm_unreachable("Caller must expand template argument packs");
break;
}
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,
const TemplateArgumentListInfo &TemplateArgs,
bool PartialTemplateArgs,
TemplateArgumentListBuilder &Converted) {
TemplateParameterList *Params = Template->getTemplateParameters();
unsigned NumParams = Params->size();
unsigned NumArgs = TemplateArgs.size();
bool Invalid = false;
SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
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;
// If we have a template parameter pack, check every remaining template
// argument against that template parameter pack.
if ((*Param)->isTemplateParameterPack()) {
Converted.BeginPack();
for (; ArgIdx < NumArgs; ++ArgIdx) {
if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
TemplateLoc, RAngleLoc, Converted)) {
Invalid = true;
break;
}
}
Converted.EndPack();
continue;
}
if (ArgIdx < NumArgs) {
// Check the template argument we were given.
if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
TemplateLoc, RAngleLoc, Converted))
return true;
continue;
}
// We have a default template argument that we will use.
TemplateArgumentLoc Arg;
// Retrieve the default template argument from the template
// parameter. For each kind of template parameter, we substitute the
// template arguments provided thus far and any "outer" template arguments
// (when the template parameter was part of a nested template) into
// the default argument.
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
if (!TTP->hasDefaultArgument()) {
assert((Invalid || PartialTemplateArgs) && "Missing default argument");
break;
}
TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
Template,
TemplateLoc,
RAngleLoc,
TTP,
Converted);
if (!ArgType)
return true;
Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
ArgType);
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
if (!NTTP->hasDefaultArgument()) {
assert((Invalid || PartialTemplateArgs) && "Missing default argument");
break;
}
Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template,
TemplateLoc,
RAngleLoc,
NTTP,
Converted);
if (E.isInvalid())
return true;
Expr *Ex = E.takeAs<Expr>();
Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
} else {
TemplateTemplateParmDecl *TempParm
= cast<TemplateTemplateParmDecl>(*Param);
if (!TempParm->hasDefaultArgument()) {
assert((Invalid || PartialTemplateArgs) && "Missing default argument");
break;
}
TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
TemplateLoc,
RAngleLoc,
TempParm,
Converted);
if (Name.isNull())
return true;
Arg = TemplateArgumentLoc(TemplateArgument(Name),
TempParm->getDefaultArgument().getTemplateQualifierRange(),
TempParm->getDefaultArgument().getTemplateNameLoc());
}
// Introduce an instantiation record that describes where we are using
// the default template argument.
InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param,
Converted.getFlatArguments(),
Converted.flatSize(),
SourceRange(TemplateLoc, RAngleLoc));
// Check the default template argument.
if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
RAngleLoc, Converted))
return true;
}
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,
TypeSourceInfo *ArgInfo) {
assert(ArgInfo && "invalid TypeSourceInfo");
QualType Arg = ArgInfo->getType();
// 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->getAs<EnumType>())
Tag = EnumT;
else if (const RecordType *RecordT = Arg->getAs<RecordType>())
Tag = RecordT;
if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) {
SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange();
return Diag(SR.getBegin(), diag::err_template_arg_local_type)
<< QualType(Tag, 0) << SR;
} else if (Tag && !Tag->getDecl()->getDeclName() &&
!Tag->getDecl()->getTypedefForAnonDecl()) {
SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange();
Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR;
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.
while (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->getLinkage() != NamedDecl::ExternalLinkage) {
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->getLinkage() != NamedDecl::ExternalLinkage) {
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,
TemplateArgument &Converted) {
bool Invalid = false;
// See through any implicit casts we added to fix the type.
while (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.
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();
}
// A pointer-to-member constant written &Class::member.
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
if (UnOp->getOpcode() == UnaryOperator::AddrOf) {
DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
if (DRE && !DRE->getQualifier())
DRE = 0;
}
}
// A constant of pointer-to-member type.
else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
if (VD->getType()->isMemberPointerType()) {
if (isa<NonTypeTemplateParmDecl>(VD) ||
(isa<VarDecl>(VD) &&
Context.getCanonicalType(VD->getType()).isConstQualified())) {
if (Arg->isTypeDependent() || Arg->isValueDependent())
Converted = TemplateArgument(Arg->Retain());
else
Converted = TemplateArgument(VD->getCanonicalDecl());
return Invalid;
}
}
}
DRE = 0;
}
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.
if (Arg->isTypeDependent() || Arg->isValueDependent())
Converted = TemplateArgument(Arg->Retain());
else
Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl());
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 (Context.hasSameType(ParamType, ArgType)) {
// Okay: no conversion necessary
} else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
!ParamType->isEnumeralType()) {
// This is an integral promotion or conversion.
ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast);
} 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->getAs<EnumType>())
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(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;
if (ParamType->isMemberPointerType())
ImpCastExprToType(Arg, ParamType, CastExpr::CK_NullToMemberPointer);
else
ImpCastExprToType(Arg, ParamType, CastExpr::CK_BitCast);
} else if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(ArgType);
ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay);
} else if (FunctionDecl *Fn
= ResolveAddressOfOverloadedFunction(Arg, ParamType, true)) {
if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
return true;
Arg = FixOverloadedFunctionReference(Arg, Fn);
ArgType = Arg->getType();
if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(Arg->getType());
ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay);
}
}
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())
return CheckTemplateArgumentPointerToMember(Arg, Converted);
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Entity)
Entity = cast<NamedDecl>(Entity->getCanonicalDecl());
Converted = TemplateArgument(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, CastExpr::CK_BitCast);
} else if (ArgType->isArrayType()) {
ArgType = Context.getArrayDecayedType(ArgType);
ImpCastExprToType(Arg, ArgType, CastExpr::CK_ArrayToPointerDecay);
}
if (IsQualificationConversion(ArgType, ParamType)) {
ArgType = ParamType;
ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp);
}
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(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(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, CastExpr::CK_NullToMemberPointer);
} else if (IsQualificationConversion(ArgType, ParamType)) {
ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp);
} 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;
}
return CheckTemplateArgumentPointerToMember(Arg, Converted);
}
/// \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,
const TemplateArgumentLoc &Arg) {
TemplateName Name = Arg.getArgument().getAsTemplate();
TemplateDecl *Template = Name.getAsTemplateDecl();
if (!Template) {
// Any dependent template name is fine.
assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
return false;
}
// 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.getLocation(), 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,
TPL_TemplateTemplateArgumentMatch,
Arg.getLocation());
}
/// \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 Kind describes how we are to match the template parameter lists.
///
/// \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,
TemplateParameterListEqualKind Kind,
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())
<< (Kind != TPL_TemplateMatch)
<< SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
<< (Kind != TPL_TemplateMatch)
<< 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)
<< (Kind != TPL_TemplateMatch);
Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration)
<< (Kind != TPL_TemplateMatch);
}
return false;
}
if (isa<TemplateTypeParmDecl>(*OldParm)) {
// Okay; all template type parameters are equivalent (since we
// know we're at the same index).
} else if (NonTypeTemplateParmDecl *OldNTTP
= dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
// The types of non-type template parameters must agree.
NonTypeTemplateParmDecl *NewNTTP
= cast<NonTypeTemplateParmDecl>(*NewParm);
// If we are matching a template template argument to a template
// template parameter and one of the non-type template parameter types
// is dependent, then we must wait until template instantiation time
// to actually compare the arguments.
if (Kind == TPL_TemplateTemplateArgumentMatch &&
(OldNTTP->getType()->isDependentType() ||
NewNTTP->getType()->isDependentType()))
continue;
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()
<< (Kind != TPL_TemplateMatch);
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.
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,
(Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind),
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 Determine what kind of template specialization the given declaration
/// is.
static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) {
if (!D)
return TSK_Undeclared;
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
return Record->getTemplateSpecializationKind();
if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
return Function->getTemplateSpecializationKind();
if (VarDecl *Var = dyn_cast<VarDecl>(D))
return Var->getTemplateSpecializationKind();
return TSK_Undeclared;
}
/// \brief Check whether a specialization is well-formed in the current
/// context.
///
/// This routine determines whether a template specialization can be declared
/// in the current context (C++ [temp.expl.spec]p2).
///
/// \param S the semantic analysis object for which this check is being
/// performed.
///
/// \param Specialized the entity being specialized or instantiated, which
/// may be a kind of template (class template, function template, etc.) or
/// a member of a class template (member function, static data member,
/// member class).
///
/// \param PrevDecl the previous declaration of this entity, if any.
///
/// \param Loc the location of the explicit specialization or instantiation of
/// this entity.
///
/// \param IsPartialSpecialization whether this is a partial specialization of
/// a class template.
///
/// \returns true if there was an error that we cannot recover from, false
/// otherwise.
static bool CheckTemplateSpecializationScope(Sema &S,
NamedDecl *Specialized,
NamedDecl *PrevDecl,
SourceLocation Loc,
bool IsPartialSpecialization) {
// Keep these "kind" numbers in sync with the %select statements in the
// various diagnostics emitted by this routine.
int EntityKind = 0;
bool isTemplateSpecialization = false;
if (isa<ClassTemplateDecl>(Specialized)) {
EntityKind = IsPartialSpecialization? 1 : 0;
isTemplateSpecialization = true;
} else if (isa<FunctionTemplateDecl>(Specialized)) {
EntityKind = 2;
isTemplateSpecialization = true;
} else if (isa<CXXMethodDecl>(Specialized))
EntityKind = 3;
else if (isa<VarDecl>(Specialized))
EntityKind = 4;
else if (isa<RecordDecl>(Specialized))
EntityKind = 5;
else {
S.Diag(Loc, diag::err_template_spec_unknown_kind);
S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
return true;
}
// 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 (S.CurContext->getLookupContext()->isFunctionOrMethod()) {
S.Diag(Loc, diag::err_template_spec_decl_function_scope)
<< Specialized;
return true;
}
if (S.CurContext->isRecord() && !IsPartialSpecialization) {
S.Diag(Loc, diag::err_template_spec_decl_class_scope)
<< Specialized;
return true;
}
// C++ [temp.class.spec]p6:
// A class template partial specialization may be declared or redeclared
// in any namespace scope in which its definition may be defined (14.5.1
// and 14.5.2).
bool ComplainedAboutScope = false;
DeclContext *SpecializedContext
= Specialized->getDeclContext()->getEnclosingNamespaceContext();
DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
if ((!PrevDecl ||
getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){
// There is no prior declaration of this entity, so this
// specialization must be in the same context as the template
// itself.
if (!DC->Equals(SpecializedContext)) {
if (isa<TranslationUnitDecl>(SpecializedContext))
S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global)
<< EntityKind << Specialized;
else if (isa<NamespaceDecl>(SpecializedContext))
S.Diag(Loc, diag::err_template_spec_decl_out_of_scope)
<< EntityKind << Specialized
<< cast<NamedDecl>(SpecializedContext);
S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
ComplainedAboutScope = true;
}
}
// Make sure that this redeclaration (or definition) occurs in an enclosing
// namespace.
// Note that HandleDeclarator() performs this check for explicit
// specializations of function templates, static data members, and member
// functions, so we skip the check here for those kinds of entities.
// FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
// Should we refactor that check, so that it occurs later?
if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) &&
!(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) ||
isa<FunctionDecl>(Specialized))) {
if (isa<TranslationUnitDecl>(SpecializedContext))
S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
<< EntityKind << Specialized;
else if (isa<NamespaceDecl>(SpecializedContext))
S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
<< EntityKind << Specialized
<< cast<NamedDecl>(SpecializedContext);
S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
}
// FIXME: check for specialization-after-instantiation errors and such.
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))) {
TemplateName Name = ArgList[I].getAsTemplate();
TemplateTemplateParmDecl *ArgDecl
= dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl());
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 RAngleLoc,
AttributeList *Attr,
MultiTemplateParamsArg TemplateParameterLists) {
assert(TUK != TUK_Reference && "References are not specializations");
// Find the class template we're specializing
TemplateName Name = TemplateD.getAsVal<TemplateName>();
ClassTemplateDecl *ClassTemplate
= dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
if (!ClassTemplate) {
Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
<< (Name.getAsTemplateDecl() &&
isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
return true;
}
bool isExplicitSpecialization = false;
bool isPartialSpecialization = false;
// Check the validity of the template headers that introduce this
// template.
// FIXME: We probably shouldn't complain about these headers for
// friend declarations.
TemplateParameterList *TemplateParams
= MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS,
(TemplateParameterList**)TemplateParameterLists.get(),
TemplateParameterLists.size(),
isExplicitSpecialization);
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->removeDefaultArgument();
}
} 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 (TTP->hasDefaultArgument()) {
Diag(TTP->getDefaultArgument().getLocation(),
diag::err_default_arg_in_partial_spec)
<< TTP->getDefaultArgument().getSourceRange();
TTP->setDefaultArgument(TemplateArgumentLoc());
}
}
}
} else if (TemplateParams) {
if (TUK == TUK_Friend)
Diag(KWLoc, diag::err_template_spec_friend)
<< CodeModificationHint::CreateRemoval(
SourceRange(TemplateParams->getTemplateLoc(),
TemplateParams->getRAngleLoc()))
<< SourceRange(LAngleLoc, RAngleLoc);
else
isExplicitSpecialization = true;
} else if (TUK != TUK_Friend) {
Diag(KWLoc, diag::err_template_spec_needs_header)
<< CodeModificationHint::CreateInsertion(KWLoc, "template<> ");
isExplicitSpecialization = true;
}
// 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.
TemplateArgumentListInfo TemplateArgs;
TemplateArgs.setLAngleLoc(LAngleLoc);
TemplateArgs.setRAngleLoc(RAngleLoc);
translateTemplateArguments(TemplateArgsIn, TemplateArgs);
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
TemplateArgs.size());
if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
TemplateArgs, 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: Diagnose friend partial specializations
// 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 (TUK != TUK_Friend &&
CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
TemplateNameLoc,
isPartialSpecialization))
return true;
// The canonical type
QualType CanonType;
if (PrevDecl &&
(PrevDecl->getSpecializationKind() == TSK_Undeclared ||
TUK == TUK_Friend)) {
// Since the only prior class template specialization with these
// arguments was referenced but not declared, or we're only
// referencing this specialization as a friend, 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.
ClassTemplatePartialSpecializationDecl *PrevPartial
= cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
ClassTemplatePartialSpecializationDecl *Partial
= ClassTemplatePartialSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
TemplateParams,
ClassTemplate,
Converted,
TemplateArgs,
PrevPartial);
if (PrevPartial) {
ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial);
ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial);
} else {
ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos);
}
Specialization = Partial;
// If we are providing an explicit specialization of a member class
// template specialization, make a note of that.
if (PrevPartial && PrevPartial->getInstantiatedFromMember())
PrevPartial->setMemberSpecialization();
// 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());
MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
TemplateParams->getDepth(),
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 or friend declaration.
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);
}
// C++ [temp.expl.spec]p6:
// If a template, a member template or the member of a class template is
// explicitly specialized then that specialization shall be declared
// before the first use of that specialization that would cause an implicit
// instantiation to take place, in every translation unit in which such a
// use occurs; no diagnostic is required.
if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
SourceRange Range(TemplateNameLoc, RAngleLoc);
Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
<< Context.getTypeDeclType(Specialization) << Range;
Diag(PrevDecl->getPointOfInstantiation(),
diag::note_instantiation_required_here)
<< (PrevDecl->getTemplateSpecializationKind()
!= TSK_ImplicitInstantiation);
return true;
}
// If this is not a friend, note that this is an explicit specialization.
if (TUK != TUK_Friend)
Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
// Check that this isn't a redefinition of this specialization.
if (TUK == TUK_Definition) {
if (RecordDecl *Def = Specialization->getDefinition(Context)) {
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, CanonType);
if (TUK != TUK_Friend)
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();
if (TUK == TUK_Friend) {
FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
TemplateNameLoc,
WrittenTy.getTypePtr(),
/*FIXME:*/KWLoc);
Friend->setAccess(AS_public);
CurContext->addDecl(Friend);
} else {
// 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();
}
/// \brief Diagnose cases where we have an explicit template specialization
/// before/after an explicit template instantiation, producing diagnostics
/// for those cases where they are required and determining whether the
/// new specialization/instantiation will have any effect.
///
/// \param NewLoc the location of the new explicit specialization or
/// instantiation.
///
/// \param NewTSK the kind of the new explicit specialization or instantiation.
///
/// \param PrevDecl the previous declaration of the entity.
///
/// \param PrevTSK the kind of the old explicit specialization or instantiatin.
///
/// \param PrevPointOfInstantiation if valid, indicates where the previus
/// declaration was instantiated (either implicitly or explicitly).
///
/// \param SuppressNew will be set to true to indicate that the new
/// specialization or instantiation has no effect and should be ignored.
///
/// \returns true if there was an error that should prevent the introduction of
/// the new declaration into the AST, false otherwise.
bool
Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
TemplateSpecializationKind NewTSK,
NamedDecl *PrevDecl,
TemplateSpecializationKind PrevTSK,
SourceLocation PrevPointOfInstantiation,
bool &SuppressNew) {
SuppressNew = false;
switch (NewTSK) {
case TSK_Undeclared:
case TSK_ImplicitInstantiation:
assert(false && "Don't check implicit instantiations here");
return false;
case TSK_ExplicitSpecialization:
switch (PrevTSK) {
case TSK_Undeclared:
case TSK_ExplicitSpecialization:
// Okay, we're just specializing something that is either already
// explicitly specialized or has merely been mentioned without any
// instantiation.
return false;
case TSK_ImplicitInstantiation:
if (PrevPointOfInstantiation.isInvalid()) {
// The declaration itself has not actually been instantiated, so it is
// still okay to specialize it.
return false;
}
// Fall through
case TSK_ExplicitInstantiationDeclaration:
case TSK_ExplicitInstantiationDefinition:
assert((PrevTSK == TSK_ImplicitInstantiation ||
PrevPointOfInstantiation.isValid()) &&
"Explicit instantiation without point of instantiation?");
// C++ [temp.expl.spec]p6:
// If a template, a member template or the member of a class template
// is explicitly specialized then that specialization shall be declared
// before the first use of that specialization that would cause an
// implicit instantiation to take place, in every translation unit in
// which such a use occurs; no diagnostic is required.
Diag(NewLoc, diag::err_specialization_after_instantiation)
<< PrevDecl;
Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
<< (PrevTSK != TSK_ImplicitInstantiation);
return true;
}
break;
case TSK_ExplicitInstantiationDeclaration:
switch (PrevTSK) {
case TSK_ExplicitInstantiationDeclaration:
// This explicit instantiation declaration is redundant (that's okay).
SuppressNew = true;
return false;
case TSK_Undeclared:
case TSK_ImplicitInstantiation:
// We're explicitly instantiating something that may have already been
// implicitly instantiated; that's fine.
return false;
case TSK_ExplicitSpecialization:
// 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.
return false;
case TSK_ExplicitInstantiationDefinition:
// C++0x [temp.explicit]p10:
// If an entity is the subject of both an explicit instantiation
// declaration and an explicit instantiation definition in the same
// translation unit, the definition shall follow the declaration.
Diag(NewLoc,
diag::err_explicit_instantiation_declaration_after_definition);
Diag(PrevPointOfInstantiation,
diag::note_explicit_instantiation_definition_here);
assert(PrevPointOfInstantiation.isValid() &&
"Explicit instantiation without point of instantiation?");
SuppressNew = true;
return false;
}
break;
case TSK_ExplicitInstantiationDefinition:
switch (PrevTSK) {
case TSK_Undeclared:
case TSK_ImplicitInstantiation:
// We're explicitly instantiating something that may have already been
// implicitly instantiated; that's fine.
return false;
case 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.
//
// In C++98/03 mode, we only give an extension warning here, because it
// is not not harmful to try to explicitly instantiate something that
// has been explicitly specialized.
if (!getLangOptions().CPlusPlus0x) {
Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization)
<< PrevDecl;
Diag(PrevDecl->getLocation(),
diag::note_previous_template_specialization);
}
SuppressNew = true;
return false;
case TSK_ExplicitInstantiationDeclaration:
// We're explicity instantiating a definition for something for which we
// were previously asked to suppress instantiations. That's fine.
return false;
case TSK_ExplicitInstantiationDefinition:
// C++0x [temp.spec]p5:
// For a given template and a given set of template-arguments,
// - an explicit instantiation definition shall appear at most once
// in a program,
Diag(NewLoc, diag::err_explicit_instantiation_duplicate)
<< PrevDecl;
Diag(PrevPointOfInstantiation,
diag::note_previous_explicit_instantiation);
SuppressNew = true;
return false;
}
break;
}
assert(false && "Missing specialization/instantiation case?");
return false;
}
/// \brief Perform semantic analysis for the given function template
/// specialization.
///
/// This routine performs all of the semantic analysis required for an
/// explicit function template specialization. On successful completion,
/// the function declaration \p FD will become a function template
/// specialization.
///
/// \param FD the function declaration, which will be updated to become a
/// function template specialization.
///
/// \param HasExplicitTemplateArgs whether any template arguments were
/// explicitly provided.
///
/// \param LAngleLoc the location of the left angle bracket ('<'), if
/// template arguments were explicitly provided.
///
/// \param ExplicitTemplateArgs the explicitly-provided template arguments,
/// if any.
///
/// \param NumExplicitTemplateArgs the number of explicitly-provided template
/// arguments. This number may be zero even when HasExplicitTemplateArgs is
/// true as in, e.g., \c void sort<>(char*, char*);
///
/// \param RAngleLoc the location of the right angle bracket ('>'), if
/// template arguments were explicitly provided.
///
/// \param PrevDecl the set of declarations that
bool
Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD,
const TemplateArgumentListInfo *ExplicitTemplateArgs,
LookupResult &Previous) {
// The set of function template specializations that could match this
// explicit function template specialization.
typedef llvm::SmallVector<FunctionDecl *, 8> CandidateSet;
CandidateSet Candidates;
DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext();
for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
I != E; ++I) {
NamedDecl *Ovl = (*I)->getUnderlyingDecl();
if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
// Only consider templates found within the same semantic lookup scope as
// FD.
if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext()))
continue;
// C++ [temp.expl.spec]p11:
// A trailing template-argument can be left unspecified in the
// template-id naming an explicit function template specialization
// provided it can be deduced from the function argument type.
// Perform template argument deduction to determine whether we may be
// specializing this template.
// FIXME: It is somewhat wasteful to build
TemplateDeductionInfo Info(Context);
FunctionDecl *Specialization = 0;
if (TemplateDeductionResult TDK
= DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs,
FD->getType(),
Specialization,
Info)) {
// FIXME: Template argument deduction failed; record why it failed, so
// that we can provide nifty diagnostics.
(void)TDK;
continue;
}
// Record this candidate.
Candidates.push_back(Specialization);
}
}
// Find the most specialized function template.
FunctionDecl *Specialization = getMostSpecialized(Candidates.data(),
Candidates.size(),
TPOC_Other,
FD->getLocation(),
PartialDiagnostic(diag::err_function_template_spec_no_match)
<< FD->getDeclName(),
PartialDiagnostic(diag::err_function_template_spec_ambiguous)
<< FD->getDeclName() << (ExplicitTemplateArgs != 0),
PartialDiagnostic(diag::note_function_template_spec_matched));
if (!Specialization)
return true;
// FIXME: Check if the prior specialization has a point of instantiation.
// If so, we have run afoul of .
// Check the scope of this explicit specialization.
if (CheckTemplateSpecializationScope(*this,
Specialization->getPrimaryTemplate(),
Specialization, FD->getLocation(),
false))
return true;
// C++ [temp.expl.spec]p6:
// If a template, a member template or the member of a class template is
// explicitly specialized then that specialization shall be declared
// before the first use of that specialization that would cause an implicit
// instantiation to take place, in every translation unit in which such a
// use occurs; no diagnostic is required.
FunctionTemplateSpecializationInfo *SpecInfo
= Specialization->getTemplateSpecializationInfo();
assert(SpecInfo && "Function template specialization info missing?");
if (SpecInfo->getPointOfInstantiation().isValid()) {
Diag(FD->getLocation(), diag::err_specialization_after_instantiation)
<< FD;
Diag(SpecInfo->getPointOfInstantiation(),
diag::note_instantiation_required_here)
<< (Specialization->getTemplateSpecializationKind()
!= TSK_ImplicitInstantiation);
return true;
}
// Mark the prior declaration as an explicit specialization, so that later
// clients know that this is an explicit specialization.
SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
// Turn the given function declaration into a function template
// specialization, with the template arguments from the previous
// specialization.
FD->setFunctionTemplateSpecialization(Context,
Specialization->getPrimaryTemplate(),
new (Context) TemplateArgumentList(
*Specialization->getTemplateSpecializationArgs()),
/*InsertPos=*/0,
TSK_ExplicitSpecialization);
// The "previous declaration" for this function template specialization is
// the prior function template specialization.
Previous.clear();
Previous.addDecl(Specialization);
return false;
}
/// \brief Perform semantic analysis for the given non-template member
/// specialization.
///
/// This routine performs all of the semantic analysis required for an
/// explicit member function specialization. On successful completion,
/// the function declaration \p FD will become a member function
/// specialization.
///
/// \param Member the member declaration, which will be updated to become a
/// specialization.
///
/// \param Previous the set of declarations, one of which may be specialized
/// by this function specialization; the set will be modified to contain the
/// redeclared member.
bool
Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) {
assert(!isa<TemplateDecl>(Member) && "Only for non-template members");
// Try to find the member we are instantiating.
NamedDecl *Instantiation = 0;
NamedDecl *InstantiatedFrom = 0;
MemberSpecializationInfo *MSInfo = 0;
if (Previous.empty()) {
// Nowhere to look anyway.
} else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) {
for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
I != E; ++I) {
NamedDecl *D = (*I)->getUnderlyingDecl();
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
if (Context.hasSameType(Function->getType(), Method->getType())) {
Instantiation = Method;
InstantiatedFrom = Method->getInstantiatedFromMemberFunction();
MSInfo = Method->getMemberSpecializationInfo();
break;
}
}
}
} else if (isa<VarDecl>(Member)) {
VarDecl *PrevVar;
if (Previous.isSingleResult() &&
(PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl())))
if (PrevVar->isStaticDataMember()) {
Instantiation = PrevVar;
InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember();
MSInfo = PrevVar->getMemberSpecializationInfo();
}
} else if (isa<RecordDecl>(Member)) {
CXXRecordDecl *PrevRecord;
if (Previous.isSingleResult() &&
(PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) {
Instantiation = PrevRecord;
InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass();
MSInfo = PrevRecord->getMemberSpecializationInfo();
}
}
if (!Instantiation) {
// There is no previous declaration that matches. Since member
// specializations are always out-of-line, the caller will complain about
// this mismatch later.
return false;
}
// Make sure that this is a specialization of a member.
if (!InstantiatedFrom) {
Diag(Member->getLocation(), diag::err_spec_member_not_instantiated)
<< Member;
Diag(Instantiation->getLocation(), diag::note_specialized_decl);
return true;
}
// C++ [temp.expl.spec]p6:
// If a template, a member template or the member of a class template is
// explicitly specialized then that spe- cialization shall be declared
// before the first use of that specialization that would cause an implicit
// instantiation to take place, in every translation unit in which such a
// use occurs; no diagnostic is required.
assert(MSInfo && "Member specialization info missing?");
if (MSInfo->getPointOfInstantiation().isValid()) {
Diag(Member->getLocation(), diag::err_specialization_after_instantiation)
<< Member;
Diag(MSInfo->getPointOfInstantiation(),
diag::note_instantiation_required_here)
<< (MSInfo->getTemplateSpecializationKind() != TSK_ImplicitInstantiation);
return true;
}
// Check the scope of this explicit specialization.
if (CheckTemplateSpecializationScope(*this,
InstantiatedFrom,
Instantiation, Member->getLocation(),
false))
return true;
// Note that this is an explicit instantiation of a member.
// the original declaration to note that it is an explicit specialization
// (if it was previously an implicit instantiation). This latter step
// makes bookkeeping easier.
if (isa<FunctionDecl>(Member)) {
FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation);
if (InstantiationFunction->getTemplateSpecializationKind() ==
TSK_ImplicitInstantiation) {
InstantiationFunction->setTemplateSpecializationKind(
TSK_ExplicitSpecialization);
InstantiationFunction->setLocation(Member->getLocation());
}
cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
cast<CXXMethodDecl>(InstantiatedFrom),
TSK_ExplicitSpecialization);
} else if (isa<VarDecl>(Member)) {
VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
if (InstantiationVar->getTemplateSpecializationKind() ==
TSK_ImplicitInstantiation) {
InstantiationVar->setTemplateSpecializationKind(
TSK_ExplicitSpecialization);
InstantiationVar->setLocation(Member->getLocation());
}
Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
cast<VarDecl>(InstantiatedFrom),
TSK_ExplicitSpecialization);
} else {
assert(isa<CXXRecordDecl>(Member) && "Only member classes remain");
CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
if (InstantiationClass->getTemplateSpecializationKind() ==
TSK_ImplicitInstantiation) {
InstantiationClass->setTemplateSpecializationKind(
TSK_ExplicitSpecialization);
InstantiationClass->setLocation(Member->getLocation());
}
cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
cast<CXXRecordDecl>(InstantiatedFrom),
TSK_ExplicitSpecialization);
}
// Save the caller the trouble of having to figure out which declaration
// this specialization matches.
Previous.clear();
Previous.addDecl(Instantiation);
return false;
}
/// \brief Check the scope of an explicit instantiation.
static void CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
SourceLocation InstLoc,
bool WasQualifiedName) {
DeclContext *ExpectedContext
= D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext();
DeclContext *CurContext = S.CurContext->getLookupContext();
// C++0x [temp.explicit]p2:
// An explicit instantiation shall appear in an enclosing namespace of its
// template.
//
// This is DR275, which we do not retroactively apply to C++98/03.
if (S.getLangOptions().CPlusPlus0x &&
!CurContext->Encloses(ExpectedContext)) {
if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext))
S.Diag(InstLoc, diag::err_explicit_instantiation_out_of_scope)
<< D << NS;
else
S.Diag(InstLoc, diag::err_explicit_instantiation_must_be_global)
<< D;
S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
return;
}
// C++0x [temp.explicit]p2:
// If the name declared in the explicit instantiation is an unqualified
// name, the explicit instantiation shall appear in the namespace where
// its template is declared or, if that namespace is inline (7.3.1), any
// namespace from its enclosing namespace set.
if (WasQualifiedName)
return;
if (CurContext->Equals(ExpectedContext))
return;
S.Diag(InstLoc, diag::err_explicit_instantiation_unqualified_wrong_namespace)
<< D << ExpectedContext;
S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
}
/// \brief Determine whether the given scope specifier has a template-id in it.
static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
if (!SS.isSet())
return false;
// C++0x [temp.explicit]p2:
// If the explicit instantiation is for a member function, a member class
// or a static data member of a class template specialization, the name of
// the class template specialization in the qualified-id for the member
// name shall be a simple-template-id.
//
// C++98 has the same restriction, just worded differently.
for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
NNS; NNS = NNS->getPrefix())
if (Type *T = NNS->getAsType())
if (isa<TemplateSpecializationType>(T))
return true;
return false;
}
// 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 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:
// There are two forms of explicit instantiation: an explicit instantiation
// definition and an explicit instantiation declaration. An explicit
// instantiation declaration begins with the extern keyword. [...]
TemplateSpecializationKind TSK
= ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
: TSK_ExplicitInstantiationDeclaration;
// Translate the parser's template argument list in our AST format.
TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
translateTemplateArguments(TemplateArgsIn, TemplateArgs);
// Check that the template argument list is well-formed for this
// template.
TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
TemplateArgs.size());
if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
TemplateArgs, 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);
// C++0x [temp.explicit]p2:
// [...] An explicit instantiation shall appear in an enclosing
// namespace of its template. [...]
//
// This is C++ DR 275.
CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
SS.isSet());
ClassTemplateSpecializationDecl *Specialization = 0;
bool ReusedDecl = false;
if (PrevDecl) {
bool SuppressNew = false;
if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
PrevDecl,
PrevDecl->getSpecializationKind(),
PrevDecl->getPointOfInstantiation(),
SuppressNew))
return DeclPtrTy::make(PrevDecl);
if (SuppressNew)
return DeclPtrTy::make(PrevDecl);
if (PrevDecl->getSpecializationKind() == TSK_ImplicitInstantiation ||
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;
ReusedDecl = true;
}
}
if (!Specialization) {
// Create a new class template specialization declaration node for
// this explicit specialization.
Specialization
= ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
ClassTemplate,
Converted, PrevDecl);
if (PrevDecl) {
// Remove the previous declaration from the folding set, since we want
// to introduce a new declaration.
ClassTemplate->getSpecializations().RemoveNode(PrevDecl);
ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
}
// Insert the new specialization.
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,
Context.getTypeDeclType(Specialization));
Specialization->setTypeAsWritten(WrittenTy);
TemplateArgsIn.release();
if (!ReusedDecl) {
// 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.
ClassTemplateSpecializationDecl *Def
= cast_or_null<ClassTemplateSpecializationDecl>(
Specialization->getDefinition(Context));
if (!Def)
InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
// Instantiate the members of this class template specialization.
Def = cast_or_null<ClassTemplateSpecializationDecl>(
Specialization->getDefinition(Context));
if (Def)
InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, 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;
bool IsDependent = false;
DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference,
KWLoc, SS, Name, NameLoc, Attr, AS_none,
MultiTemplateParamsArg(*this, 0, 0),
Owned, IsDependent);
assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
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:
// If the explicit instantiation is for a class or member class, the
// elaborated-type-specifier in the declaration shall include a
// simple-template-id.
//
// C++98 has the same restriction, just worded differently.
if (!ScopeSpecifierHasTemplateId(SS))
Diag(TemplateLoc, diag::err_explicit_instantiation_without_qualified_id)
<< Record << SS.getRange();
// C++0x [temp.explicit]p2:
// There are two forms of explicit instantiation: an explicit instantiation
// definition and an explicit instantiation declaration. An explicit
// instantiation declaration begins with the extern keyword. [...]
TemplateSpecializationKind TSK
= ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
: TSK_ExplicitInstantiationDeclaration;
// C++0x [temp.explicit]p2:
// [...] An explicit instantiation shall appear in an enclosing
// namespace of its template. [...]
//
// This is C++ DR 275.
CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
// Verify that it is okay to explicitly instantiate here.
CXXRecordDecl *PrevDecl
= cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration());
if (!PrevDecl && Record->getDefinition(Context))
PrevDecl = Record;
if (PrevDecl) {
MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
bool SuppressNew = false;
assert(MSInfo && "No member specialization information?");
if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
PrevDecl,
MSInfo->getTemplateSpecializationKind(),
MSInfo->getPointOfInstantiation(),
SuppressNew))
return true;
if (SuppressNew)
return TagD;
}
CXXRecordDecl *RecordDef
= cast_or_null<CXXRecordDecl>(Record->getDefinition(Context));
if (!RecordDef) {
// C++ [temp.explicit]p3:
// A definition of a member class of a class template shall be in scope
// at the point of an explicit instantiation of the member class.
CXXRecordDecl *Def
= cast_or_null<CXXRecordDecl>(Pattern->getDefinition(Context));
if (!Def) {
Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
<< 0 << Record->getDeclName() << Record->getDeclContext();
Diag(Pattern->getLocation(), diag::note_forward_declaration)
<< Pattern;
return true;
} else {
if (InstantiateClass(NameLoc, Record, Def,
getTemplateInstantiationArgs(Record),
TSK))
return true;
RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context));
if (!RecordDef)
return true;
}
}
// Instantiate all of the members of the class.
InstantiateClassMembers(NameLoc, RecordDef,
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::DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
SourceLocation ExternLoc,
SourceLocation TemplateLoc,
Declarator &D) {
// Explicit instantiations always require a name.
DeclarationName Name = GetNameForDeclarator(D);
if (!Name) {
if (!D.isInvalidType())
Diag(D.getDeclSpec().getSourceRange().getBegin(),
diag::err_explicit_instantiation_requires_name)
<< D.getDeclSpec().getSourceRange()
<< D.getSourceRange();
return true;
}
// The scope passed in may not be a decl scope. Zip up the scope tree until
// we find one that is.
while ((S->getFlags() & Scope::DeclScope) == 0 ||
(S->getFlags() & Scope::TemplateParamScope) != 0)
S = S->getParent();
// Determine the type of the declaration.
QualType R = GetTypeForDeclarator(D, S, 0);
if (R.isNull())
return true;
if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
// Cannot explicitly instantiate a typedef.
Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
<< Name;
return true;
}
// C++0x [temp.explicit]p1:
// [...] An explicit instantiation of a function template shall not use the
// inline or constexpr specifiers.
// Presumably, this also applies to member functions of class templates as
// well.
if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x)
Diag(D.getDeclSpec().getInlineSpecLoc(),
diag::err_explicit_instantiation_inline)
<<CodeModificationHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
// FIXME: check for constexpr specifier.
// C++0x [temp.explicit]p2:
// There are two forms of explicit instantiation: an explicit instantiation
// definition and an explicit instantiation declaration. An explicit
// instantiation declaration begins with the extern keyword. [...]
TemplateSpecializationKind TSK
= ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
: TSK_ExplicitInstantiationDeclaration;
LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName);
LookupParsedName(Previous, S, &D.getCXXScopeSpec());
if (!R->isFunctionType()) {
// C++ [temp.explicit]p1:
// A [...] static data member of a class template can be explicitly
// instantiated from the member definition associated with its class
// template.
if (Previous.isAmbiguous())
return true;
VarDecl *Prev = Previous.getAsSingle<VarDecl>();
if (!Prev || !Prev->isStaticDataMember()) {
// We expect to see a data data member here.
Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
<< Name;
for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
P != PEnd; ++P)
Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
return true;
}
if (!Prev->getInstantiatedFromStaticDataMember()) {
// FIXME: Check for explicit specialization?
Diag(D.getIdentifierLoc(),
diag::err_explicit_instantiation_data_member_not_instantiated)
<< Prev;
Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
// FIXME: Can we provide a note showing where this was declared?
return true;
}
// C++0x [temp.explicit]p2:
// If the explicit instantiation is for a member function, a member class
// or a static data member of a class template specialization, the name of
// the class template specialization in the qualified-id for the member
// name shall be a simple-template-id.
//
// C++98 has the same restriction, just worded differently.
if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
Diag(D.getIdentifierLoc(),
diag::err_explicit_instantiation_without_qualified_id)
<< Prev << D.getCXXScopeSpec().getRange();
// Check the scope of this explicit instantiation.
CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
// Verify that it is okay to explicitly instantiate here.
MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo();
assert(MSInfo && "Missing static data member specialization info?");
bool SuppressNew = false;
if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
MSInfo->getTemplateSpecializationKind(),
MSInfo->getPointOfInstantiation(),
SuppressNew))
return true;
if (SuppressNew)
return DeclPtrTy();
// Instantiate static data member.
Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
if (TSK == TSK_ExplicitInstantiationDefinition)
InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false,
/*DefinitionRequired=*/true);
// FIXME: Create an ExplicitInstantiation node?
return DeclPtrTy();
}
// If the declarator is a template-id, translate the parser's template
// argument list into our AST format.
bool HasExplicitTemplateArgs = false;
TemplateArgumentListInfo TemplateArgs;
if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
ASTTemplateArgsPtr TemplateArgsPtr(*this,
TemplateId->getTemplateArgs(),
TemplateId->NumArgs);
translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
HasExplicitTemplateArgs = true;
TemplateArgsPtr.release();
}
// C++ [temp.explicit]p1:
// A [...] function [...] can be explicitly instantiated from its template.
// A member function [...] of a class template can be explicitly
// instantiated from the member definition associated with its class
// template.
llvm::SmallVector<FunctionDecl *, 8> Matches;
for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
P != PEnd; ++P) {
NamedDecl *Prev = *P;
if (!HasExplicitTemplateArgs) {
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
if (Context.hasSameUnqualifiedType(Method->getType(), R)) {
Matches.clear();
Matches.push_back(Method);
break;
}
}
}
FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
if (!FunTmpl)
continue;
TemplateDeductionInfo Info(Context);
FunctionDecl *Specialization = 0;
if (TemplateDeductionResult TDK
= DeduceTemplateArguments(FunTmpl,
(HasExplicitTemplateArgs ? &TemplateArgs : 0),
R, Specialization, Info)) {
// FIXME: Keep track of almost-matches?
(void)TDK;
continue;
}
Matches.push_back(Specialization);
}
// Find the most specialized function template specialization.
FunctionDecl *Specialization
= getMostSpecialized(Matches.data(), Matches.size(), TPOC_Other,
D.getIdentifierLoc(),
PartialDiagnostic(diag::err_explicit_instantiation_not_known) << Name,
PartialDiagnostic(diag::err_explicit_instantiation_ambiguous) << Name,
PartialDiagnostic(diag::note_explicit_instantiation_candidate));
if (!Specialization)
return true;
if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
Diag(D.getIdentifierLoc(),
diag::err_explicit_instantiation_member_function_not_instantiated)
<< Specialization
<< (Specialization->getTemplateSpecializationKind() ==
TSK_ExplicitSpecialization);
Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
return true;
}
FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration();
if (!PrevDecl && Specialization->isThisDeclarationADefinition())
PrevDecl = Specialization;
if (PrevDecl) {
bool SuppressNew = false;
if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
PrevDecl,
PrevDecl->getTemplateSpecializationKind(),
PrevDecl->getPointOfInstantiation(),
SuppressNew))
return true;
// FIXME: We may still want to build some representation of this
// explicit specialization.
if (SuppressNew)
return DeclPtrTy();
}
Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
if (TSK == TSK_ExplicitInstantiationDefinition)
InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization,
false, /*DefinitionRequired=*/true);
// C++0x [temp.explicit]p2:
// If the explicit instantiation is for a member function, a member class
// or a static data member of a class template specialization, the name of
// the class template specialization in the qualified-id for the member
// name shall be a simple-template-id.
//
// C++98 has the same restriction, just worded differently.
FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
D.getCXXScopeSpec().isSet() &&
!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
Diag(D.getIdentifierLoc(),
diag::err_explicit_instantiation_without_qualified_id)
<< Specialization << D.getCXXScopeSpec().getRange();
CheckExplicitInstantiationScope(*this,
FunTmpl? (NamedDecl *)FunTmpl
: Specialization->getInstantiatedFromMemberFunction(),
D.getIdentifierLoc(),
D.getCXXScopeSpec().isSet());
// FIXME: Create some kind of ExplicitInstantiationDecl here.
return DeclPtrTy();
}
Sema::TypeResult
Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
const CXXScopeSpec &SS, IdentifierInfo *Name,
SourceLocation TagLoc, SourceLocation NameLoc) {
// This has to hold, because SS is expected to be defined.
assert(Name && "Expected a name in a dependent tag");
NestedNameSpecifier *NNS
= static_cast<NestedNameSpecifier *>(SS.getScopeRep());
if (!NNS)
return true;
QualType T = CheckTypenameType(NNS, *Name, SourceRange(TagLoc, NameLoc));
if (T.isNull())
return true;
TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec);
QualType ElabType = Context.getElaboratedType(T, TagKind);
return ElabType.getAsOpaquePtr();
}
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->getAs<TemplateSpecializationType>();
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(*this, Name, Range.getEnd(), LookupOrdinaryName);
LookupQualifiedName(Result, Ctx);
unsigned DiagID = 0;
Decl *Referenced = 0;
switch (Result.getResultKind()) {
case LookupResult::NotFound:
DiagID = diag::err_typename_nested_not_found;
break;
case LookupResult::Found:
if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
// 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.getFoundDecl();
break;
case LookupResult::FoundUnresolvedValue:
llvm_unreachable("unresolved using decl in non-dependent context");
return QualType();
case LookupResult::FoundOverloaded:
DiagID = diag::err_typename_nested_not_type;
Referenced = *Result.begin();
break;
case LookupResult::Ambiguous:
return QualType();
}
// If we get here, it's because name lookup did not find a
// type. Emit an appropriate diagnostic and return an error.
Diag(Range.getEnd(), DiagID) << Range << Name << Ctx;
if (Referenced)
Diag(Referenced->getLocation(), diag::note_typename_refers_here)
<< Name;
return QualType();
}
namespace {
// See Sema::RebuildTypeInCurrentInstantiation
class 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 Sets the "base" location and entity when that
/// information is known based on another transformation.
void setBase(SourceLocation Loc, DeclarationName Entity) {
this->Loc = Loc;
this->Entity = 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(TypeLocBuilder &TLB, TypenameTypeLoc TL);
};
}
QualType
CurrentInstantiationRebuilder::TransformTypenameType(TypeLocBuilder &TLB,
TypenameTypeLoc TL) {
TypenameType *T = TL.getTypePtr();
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);
QualType Result;
if (NNS == T->getQualifier() && getSema().computeDeclContext(SS) == 0)
Result = QualType(T, 0);
// Rebuild the typename type, which will probably turn into a
// QualifiedNameType.
else 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))
Result = QualType(T, 0);
else
Result = getDerived().RebuildTypenameType(NNS, NewTemplateId);
} else
Result = getDerived().RebuildTypenameType(NNS, T->getIdentifier(),
SourceRange(TL.getNameLoc()));
TypenameTypeLoc NewTL = TLB.push<TypenameTypeLoc>(Result);
NewTL.setNameLoc(TL.getNameLoc());
return Result;
}
/// \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);
}
/// \brief Produces a formatted string that describes the binding of
/// template parameters to template arguments.
std::string
Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
const TemplateArgumentList &Args) {
// FIXME: For variadic templates, we'll need to get the structured list.
return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(),
Args.flat_size());
}
std::string
Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
const TemplateArgument *Args,
unsigned NumArgs) {
std::string Result;
if (!Params || Params->size() == 0 || NumArgs == 0)
return Result;
for (unsigned I = 0, N = Params->size(); I != N; ++I) {
if (I >= NumArgs)
break;
if (I == 0)
Result += "[with ";
else
Result += ", ";
if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
Result += Id->getName();
} else {
Result += '$';
Result += llvm::utostr(I);
}
Result += " = ";
switch (Args[I].getKind()) {
case TemplateArgument::Null:
Result += "<no value>";
break;
case TemplateArgument::Type: {
std::string TypeStr;
Args[I].getAsType().getAsStringInternal(TypeStr,
Context.PrintingPolicy);
Result += TypeStr;
break;
}
case TemplateArgument::Declaration: {
bool Unnamed = true;
if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) {
if (ND->getDeclName()) {
Unnamed = false;
Result += ND->getNameAsString();
}
}
if (Unnamed) {
Result += "<anonymous>";
}
break;
}
case TemplateArgument::Template: {
std::string Str;
llvm::raw_string_ostream OS(Str);
Args[I].getAsTemplate().print(OS, Context.PrintingPolicy);
Result += OS.str();
break;
}
case TemplateArgument::Integral: {
Result += Args[I].getAsIntegral()->toString(10);
break;
}
case TemplateArgument::Expression: {
assert(false && "No expressions in deduced template arguments!");
Result += "<expression>";
break;
}
case TemplateArgument::Pack:
// FIXME: Format template argument packs
Result += "<template argument pack>";
break;
}
}
Result += ']';
return Result;
}