blob: 5b2e89e8b0d444c4838e9020edb735862c457f9a [file] [log] [blame]
//===------- 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 "clang/AST/ASTContext.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/Parse/DeclSpec.h"
#include "clang/Basic/LangOptions.h"
using namespace clang;
/// isTemplateName - Determines whether the identifier II is a
/// template name in the current scope, and returns the template
/// declaration if II names a template. An optional CXXScope can be
/// passed to indicate the C++ scope in which the identifier will be
/// found.
TemplateNameKind Sema::isTemplateName(IdentifierInfo &II, Scope *S,
DeclTy *&Template,
const CXXScopeSpec *SS) {
NamedDecl *IIDecl = LookupParsedName(S, SS, &II, LookupOrdinaryName);
if (IIDecl) {
if (isa<TemplateDecl>(IIDecl)) {
Template = IIDecl;
if (isa<FunctionTemplateDecl>(IIDecl))
return TNK_Function_template;
else if (isa<ClassTemplateDecl>(IIDecl))
return TNK_Class_template;
else if (isa<TemplateTemplateParmDecl>(IIDecl))
return TNK_Template_template_parm;
else
assert(false && "Unknown TemplateDecl");
}
// FIXME: What follows is a gross hack.
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(IIDecl)) {
if (FD->getType()->isDependentType()) {
Template = FD;
return TNK_Function_template;
}
} else if (OverloadedFunctionDecl *Ovl
= dyn_cast<OverloadedFunctionDecl>(IIDecl)) {
for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(),
FEnd = Ovl->function_end();
F != FEnd; ++F) {
if ((*F)->getType()->isDependentType()) {
Template = Ovl;
return TNK_Function_template;
}
}
}
}
return TNK_Non_template;
}
/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
/// that the template parameter 'PrevDecl' is being shadowed by a new
/// declaration at location Loc. Returns true to indicate that this is
/// an error, and false otherwise.
bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
// Microsoft Visual C++ permits template parameters to be shadowed.
if (getLangOptions().Microsoft)
return false;
// C++ [temp.local]p4:
// A template-parameter shall not be redeclared within its
// scope (including nested scopes).
Diag(Loc, diag::err_template_param_shadow)
<< cast<NamedDecl>(PrevDecl)->getDeclName();
Diag(PrevDecl->getLocation(), diag::note_template_param_here);
return true;
}
/// AdjustDeclForTemplates - 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(DeclTy *&D)
{
if(TemplateDecl *Temp = dyn_cast<TemplateDecl>(static_cast<Decl*>(D))) {
D = Temp->getTemplatedDecl();
return Temp;
}
return 0;
}
/// ActOnTypeParameter - Called when a C++ template type parameter
/// (e.g., "typename T") has been parsed. Typename specifies whether
/// the keyword "typename" was used to declare the type parameter
/// (otherwise, "class" was used), and KeyLoc is the location of the
/// "class" or "typename" keyword. ParamName is the name of the
/// parameter (NULL indicates an unnamed template parameter) and
/// ParamName is the location of the parameter name (if any).
/// If the type parameter has a default argument, it will be added
/// later via ActOnTypeParameterDefault.
Sema::DeclTy *Sema::ActOnTypeParameter(Scope *S, bool Typename,
SourceLocation KeyLoc,
IdentifierInfo *ParamName,
SourceLocation ParamNameLoc,
unsigned Depth, unsigned Position) {
assert(S->isTemplateParamScope() &&
"Template type parameter not in template parameter scope!");
bool Invalid = false;
if (ParamName) {
NamedDecl *PrevDecl = LookupName(S, ParamName, LookupTagName);
if (PrevDecl && PrevDecl->isTemplateParameter())
Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
PrevDecl);
}
SourceLocation Loc = ParamNameLoc;
if (!ParamName)
Loc = KeyLoc;
TemplateTypeParmDecl *Param
= TemplateTypeParmDecl::Create(Context, CurContext, Loc,
Depth, Position, ParamName, Typename);
if (Invalid)
Param->setInvalidDecl();
if (ParamName) {
// Add the template parameter into the current scope.
S->AddDecl(Param);
IdResolver.AddDecl(Param);
}
return Param;
}
/// ActOnTypeParameterDefault - Adds a default argument (the type
/// Default) to the given template type parameter (TypeParam).
void Sema::ActOnTypeParameterDefault(DeclTy *TypeParam,
SourceLocation EqualLoc,
SourceLocation DefaultLoc,
TypeTy *DefaultT) {
TemplateTypeParmDecl *Parm
= cast<TemplateTypeParmDecl>(static_cast<Decl *>(TypeParam));
QualType Default = QualType::getFromOpaquePtr(DefaultT);
// C++ [temp.param]p14:
// A template-parameter shall not be used in its own default argument.
// FIXME: Implement this check! Needs a recursive walk over the types.
// Check the template argument itself.
if (CheckTemplateArgument(Parm, Default, DefaultLoc)) {
Parm->setInvalidDecl();
return;
}
Parm->setDefaultArgument(Default, DefaultLoc, false);
}
/// 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::DeclTy *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
unsigned Depth,
unsigned Position) {
QualType T = GetTypeForDeclarator(D, S);
assert(S->isTemplateParamScope() &&
"Non-type template parameter not in template parameter scope!");
bool Invalid = false;
IdentifierInfo *ParamName = D.getIdentifier();
if (ParamName) {
NamedDecl *PrevDecl = LookupName(S, ParamName, LookupTagName);
if (PrevDecl && PrevDecl->isTemplateParameter())
Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
PrevDecl);
}
// 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->getAsPointerType()->getPointeeType()->isObjectType() ||
T->getAsPointerType()->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()) {
// Okay: The template parameter is well-formed.
}
// 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?
T = Context.getArrayDecayedType(T);
else if (T->isFunctionType())
// FIXME: Keep the type prior to promotion?
T = Context.getPointerType(T);
else {
Diag(D.getIdentifierLoc(), diag::err_template_nontype_parm_bad_type)
<< T;
return 0;
}
NonTypeTemplateParmDecl *Param
= NonTypeTemplateParmDecl::Create(Context, CurContext, D.getIdentifierLoc(),
Depth, Position, ParamName, T);
if (Invalid)
Param->setInvalidDecl();
if (D.getIdentifier()) {
// Add the template parameter into the current scope.
S->AddDecl(Param);
IdResolver.AddDecl(Param);
}
return Param;
}
/// \brief Adds a default argument to the given non-type template
/// parameter.
void Sema::ActOnNonTypeTemplateParameterDefault(DeclTy *TemplateParamD,
SourceLocation EqualLoc,
ExprArg DefaultE) {
NonTypeTemplateParmDecl *TemplateParm
= cast<NonTypeTemplateParmDecl>(static_cast<Decl *>(TemplateParamD));
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.
if (CheckTemplateArgument(TemplateParm, Default)) {
TemplateParm->setInvalidDecl();
return;
}
TemplateParm->setDefaultArgument(static_cast<Expr *>(DefaultE.release()));
}
/// 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::DeclTy *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(Param);
IdResolver.AddDecl(Param);
}
return Param;
}
/// \brief Adds a default argument to the given template template
/// parameter.
void Sema::ActOnTemplateTemplateParameterDefault(DeclTy *TemplateParamD,
SourceLocation EqualLoc,
ExprArg DefaultE) {
TemplateTemplateParmDecl *TemplateParm
= cast<TemplateTemplateParmDecl>(static_cast<Decl *>(TemplateParamD));
// Since a template-template parameter's default argument is an
// id-expression, it must be a DeclRefExpr.
DeclRefExpr *Default
= cast<DeclRefExpr>(static_cast<Expr *>(DefaultE.get()));
// C++ [temp.param]p14:
// A template-parameter shall not be used in its own default argument.
// FIXME: Implement this check! Needs a recursive walk over the types.
// Check the well-formedness of the template argument.
if (!isa<TemplateDecl>(Default->getDecl())) {
Diag(Default->getSourceRange().getBegin(),
diag::err_template_arg_must_be_template)
<< Default->getSourceRange();
TemplateParm->setInvalidDecl();
return;
}
if (CheckTemplateArgument(TemplateParm, Default)) {
TemplateParm->setInvalidDecl();
return;
}
DefaultE.release();
TemplateParm->setDefaultArgument(Default);
}
/// ActOnTemplateParameterList - Builds a TemplateParameterList that
/// contains the template parameters in Params/NumParams.
Sema::TemplateParamsTy *
Sema::ActOnTemplateParameterList(unsigned Depth,
SourceLocation ExportLoc,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
DeclTy **Params, unsigned NumParams,
SourceLocation RAngleLoc) {
if (ExportLoc.isValid())
Diag(ExportLoc, diag::note_template_export_unsupported);
return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
(Decl**)Params, NumParams, RAngleLoc);
}
Sema::DeclTy *
Sema::ActOnClassTemplate(Scope *S, unsigned TagSpec, TagKind TK,
SourceLocation KWLoc, const CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
AttributeList *Attr,
MultiTemplateParamsArg TemplateParameterLists) {
assert(TemplateParameterLists.size() > 0 && "No template parameter lists?");
assert(TK != TK_Reference && "Can only declare or define class templates");
bool Invalid = false;
// Check that we can declare a template here.
if (CheckTemplateDeclScope(S, TemplateParameterLists))
return 0;
TagDecl::TagKind Kind;
switch (TagSpec) {
default: assert(0 && "Unknown tag type!");
case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break;
case DeclSpec::TST_union: Kind = TagDecl::TK_union; break;
case DeclSpec::TST_class: Kind = TagDecl::TK_class; break;
}
// There is no such thing as an unnamed class template.
if (!Name) {
Diag(KWLoc, diag::err_template_unnamed_class);
return 0;
}
// Find any previous declaration with this name.
LookupResult Previous = LookupParsedName(S, &SS, Name, LookupOrdinaryName,
true);
assert(!Previous.isAmbiguous() && "Ambiguity in class template redecl?");
NamedDecl *PrevDecl = 0;
if (Previous.begin() != Previous.end())
PrevDecl = *Previous.begin();
DeclContext *SemanticContext = CurContext;
if (SS.isNotEmpty() && !SS.isInvalid()) {
SemanticContext = static_cast<DeclContext*>(SS.getScopeRep());
// FIXME: need to match up several levels of template parameter
// lists here.
}
// FIXME: member templates!
TemplateParameterList *TemplateParams
= static_cast<TemplateParameterList *>(*TemplateParameterLists.release());
// If there is a previous declaration with the same name, check
// whether this is a valid redeclaration.
ClassTemplateDecl *PrevClassTemplate
= dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
if (PrevClassTemplate) {
// Ensure that the template parameter lists are compatible.
if (!TemplateParameterListsAreEqual(TemplateParams,
PrevClassTemplate->getTemplateParameters(),
/*Complain=*/true))
return 0;
// 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 (PrevRecordDecl->getTagKind() != Kind) {
Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
return 0;
}
// Check for redefinition of this class template.
if (TK == TK_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 0;
}
}
} 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 0;
}
// Check the template parameter list of this declaration, possibly
// merging in the template parameter list from the previous class
// template declaration.
if (CheckTemplateParameterList(TemplateParams,
PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0))
Invalid = true;
// If we had a scope specifier, we better have a previous template
// declaration!
TagDecl *NewClass =
CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name,
PrevClassTemplate?
PrevClassTemplate->getTemplatedDecl() : 0);
ClassTemplateDecl *NewTemplate
= ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
DeclarationName(Name), TemplateParams,
NewClass);
// Set the lexical context of these templates
NewClass->setLexicalDeclContext(CurContext);
NewTemplate->setLexicalDeclContext(CurContext);
if (TK == TK_Definition)
NewClass->startDefinition();
if (Attr)
ProcessDeclAttributeList(NewClass, Attr);
PushOnScopeChains(NewTemplate, S);
if (Invalid) {
NewTemplate->setInvalidDecl();
NewClass->setInvalidDecl();
}
return NewTemplate;
}
/// \brief Checks the validity of a template parameter list, possibly
/// considering the template parameter list from a previous
/// declaration.
///
/// If an "old" template parameter list is provided, it must be
/// equivalent (per TemplateParameterListsAreEqual) to the "new"
/// template parameter list.
///
/// \param NewParams Template parameter list for a new template
/// declaration. This template parameter list will be updated with any
/// default arguments that are carried through from the previous
/// template parameter list.
///
/// \param OldParams If provided, template parameter list from a
/// previous declaration of the same template. Default template
/// arguments will be merged from the old template parameter list to
/// the new template parameter list.
///
/// \returns true if an error occurred, false otherwise.
bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
TemplateParameterList *OldParams) {
bool Invalid = false;
// C++ [temp.param]p10:
// The set of default template-arguments available for use with a
// template declaration or definition is obtained by merging the
// default arguments from the definition (if in scope) and all
// declarations in scope in the same way default function
// arguments are (8.3.6).
bool SawDefaultArgument = false;
SourceLocation PreviousDefaultArgLoc;
// 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;
// Merge default arguments for template type parameters.
if (TemplateTypeParmDecl *NewTypeParm
= dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
TemplateTypeParmDecl *OldTypeParm
= OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
NewTypeParm->hasDefaultArgument()) {
OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
SawDefaultArgument = true;
RedundantDefaultArg = true;
PreviousDefaultArgLoc = NewDefaultLoc;
} else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
// Merge the default argument from the old declaration to the
// new declaration.
SawDefaultArgument = true;
NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgument(),
OldTypeParm->getDefaultArgumentLoc(),
true);
PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
} else if (NewTypeParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
} else if (SawDefaultArgument)
MissingDefaultArg = true;
}
// Merge default arguments for non-type template parameters
else if (NonTypeTemplateParmDecl *NewNonTypeParm
= dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
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;
}
// Merge default arguments for template template parameters
else {
TemplateTemplateParmDecl *NewTemplateParm
= cast<TemplateTemplateParmDecl>(*NewParam);
TemplateTemplateParmDecl *OldTemplateParm
= OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
NewTemplateParm->hasDefaultArgument()) {
OldDefaultLoc = OldTemplateParm->getDefaultArgumentLoc();
NewDefaultLoc = NewTemplateParm->getDefaultArgumentLoc();
SawDefaultArgument = true;
RedundantDefaultArg = true;
PreviousDefaultArgLoc = NewDefaultLoc;
} else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
// Merge the default argument from the old declaration to the
// new declaration.
SawDefaultArgument = true;
// FIXME: We need to create a new kind of "default argument"
// expression that points to a previous template template
// parameter.
NewTemplateParm->setDefaultArgument(
OldTemplateParm->getDefaultArgument());
PreviousDefaultArgLoc = OldTemplateParm->getDefaultArgumentLoc();
} else if (NewTemplateParm->hasDefaultArgument()) {
SawDefaultArgument = true;
PreviousDefaultArgLoc = NewTemplateParm->getDefaultArgumentLoc();
} else if (SawDefaultArgument)
MissingDefaultArg = true;
}
if (RedundantDefaultArg) {
// C++ [temp.param]p12:
// A template-parameter shall not be given default arguments
// by two different declarations in the same scope.
Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
Invalid = true;
} else if (MissingDefaultArg) {
// C++ [temp.param]p11:
// If a template-parameter has a default template-argument,
// all subsequent template-parameters shall have a default
// template-argument supplied.
Diag((*NewParam)->getLocation(),
diag::err_template_param_default_arg_missing);
Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
Invalid = true;
}
// If we have an old template parameter list that we're merging
// in, move on to the next parameter.
if (OldParams)
++OldParam;
}
return Invalid;
}
Action::TypeResult
Sema::ActOnClassTemplateId(DeclTy *TemplateD, SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgs,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc,
const CXXScopeSpec *SS) {
TemplateDecl *Template = cast<TemplateDecl>(static_cast<Decl *>(TemplateD));
ClassTemplateDecl *ClassTemplate = cast<ClassTemplateDecl>(Template);
// Check that the template argument list is well-formed for this
// template.
llvm::SmallVector<TemplateArgument, 16> ConvertedTemplateArgs;
if (CheckTemplateArgumentList(Template, TemplateLoc, LAngleLoc,
TemplateArgs, TemplateArgLocs, RAngleLoc,
ConvertedTemplateArgs))
return true;
assert((ConvertedTemplateArgs.size() ==
Template->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, &ConvertedTemplateArgs[0],
ConvertedTemplateArgs.size());
void *InsertPos = 0;
ClassTemplateSpecializationDecl *Decl
= ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
if (!Decl) {
// This is the first time we have referenced this class template
// specialization. Create the canonical declaration and add it to
// the set of specializations.
Decl = ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateLoc,
ClassTemplate,
&ConvertedTemplateArgs[0],
ConvertedTemplateArgs.size(),
0);
ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos);
Decl->setLexicalDeclContext(CurContext);
}
// Build the fully-sugared type for this class template
// specialization, which refers back to the class template
// specialization we created or found.
QualType Result
= Context.getClassTemplateSpecializationType(Template,
TemplateArgs.size(),
reinterpret_cast<uintptr_t *>(TemplateArgs.getArgs()),
TemplateArgs.getArgIsType(),
Context.getTypeDeclType(Decl));
TemplateArgs.release();
return Result.getAsOpaquePtr();
}
/// \brief Check that the given template argument list is well-formed
/// for specializing the given template.
bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr& Args,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc,
llvm::SmallVectorImpl<TemplateArgument> &Converted) {
TemplateParameterList *Params = Template->getTemplateParameters();
unsigned NumParams = Params->size();
unsigned NumArgs = Args.size();
bool Invalid = false;
if (NumArgs > NumParams ||
NumArgs < Params->getMinRequiredArguments()) {
// 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(TemplateArgLocs[NumParams], 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) {
// Decode the template argument
QualType ArgType;
Expr *ArgExpr = 0;
SourceLocation ArgLoc;
if (ArgIdx >= NumArgs) {
// Retrieve the default template argument from the template
// parameter.
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
if (!TTP->hasDefaultArgument())
break;
ArgType = TTP->getDefaultArgument();
ArgLoc = TTP->getDefaultArgumentLoc();
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
if (!NTTP->hasDefaultArgument())
break;
ArgExpr = NTTP->getDefaultArgument();
ArgLoc = NTTP->getDefaultArgumentLoc();
} else {
TemplateTemplateParmDecl *TempParm
= cast<TemplateTemplateParmDecl>(*Param);
if (!TempParm->hasDefaultArgument())
break;
ArgExpr = TempParm->getDefaultArgument();
ArgLoc = TempParm->getDefaultArgumentLoc();
}
} else {
// Retrieve the template argument produced by the user.
ArgLoc = TemplateArgLocs[ArgIdx];
if (Args.getArgIsType()[ArgIdx])
ArgType = QualType::getFromOpaquePtr(Args.getArgs()[ArgIdx]);
else
ArgExpr = reinterpret_cast<Expr *>(Args.getArgs()[ArgIdx]);
}
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
// Check template type parameters.
if (!ArgType.isNull()) {
if (CheckTemplateArgument(TTP, ArgType, ArgLoc))
Invalid = true;
// Add the converted template type argument.
Converted.push_back(
TemplateArgument(Context.getCanonicalType(ArgType)));
continue;
}
// 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 an expression.
Diag(ArgExpr->getSourceRange().getBegin(),
diag::err_template_arg_must_be_type);
Diag((*Param)->getLocation(), diag::note_template_param_here);
Invalid = true;
} else if (NonTypeTemplateParmDecl *NTTP
= dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
// Check non-type template parameters.
if (ArgExpr) {
if (CheckTemplateArgument(NTTP, ArgExpr, &Converted))
Invalid = true;
continue;
}
// We have a non-type template parameter but the template
// argument is a type.
// C++ [temp.arg]p2:
// In a template-argument, an ambiguity between a type-id and
// an expression is resolved to a type-id, regardless of the
// form of the corresponding template-parameter.
//
// We warn specifically about this case, since it can be rather
// confusing for users.
if (ArgType->isFunctionType())
Diag(ArgLoc, diag::err_template_arg_nontype_ambig)
<< ArgType;
else
Diag(ArgLoc, diag::err_template_arg_must_be_expr);
Diag((*Param)->getLocation(), diag::note_template_param_here);
Invalid = true;
} else {
// Check template template parameters.
TemplateTemplateParmDecl *TempParm
= cast<TemplateTemplateParmDecl>(*Param);
if (ArgExpr && isa<DeclRefExpr>(ArgExpr) &&
isa<TemplateDecl>(cast<DeclRefExpr>(ArgExpr)->getDecl())) {
if (CheckTemplateArgument(TempParm, cast<DeclRefExpr>(ArgExpr)))
Invalid = true;
// Add the converted template argument.
// FIXME: Need the "canonical" template declaration!
Converted.push_back(
TemplateArgument(cast<DeclRefExpr>(ArgExpr)->getDecl()));
continue;
}
// We have a template template parameter but the template
// argument does not refer to a template.
Diag(ArgLoc, diag::err_template_arg_must_be_template);
Invalid = 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,
QualType Arg, SourceLocation ArgLoc) {
// C++ [temp.arg.type]p2:
// A local type, a type with no linkage, an unnamed type or a type
// compounded from any of these types shall not be used as a
// template-argument for a template type-parameter.
//
// FIXME: Perform the recursive and no-linkage type checks.
const TagType *Tag = 0;
if (const EnumType *EnumT = Arg->getAsEnumType())
Tag = EnumT;
else if (const RecordType *RecordT = Arg->getAsRecordType())
Tag = RecordT;
if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod())
return Diag(ArgLoc, diag::err_template_arg_local_type)
<< QualType(Tag, 0);
else if (Tag && !Tag->getDecl()->getDeclName()) {
Diag(ArgLoc, diag::err_template_arg_unnamed_type);
Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here);
return true;
}
return false;
}
/// \brief Checks whether the given template argument is the address
/// of an object or function according to C++ [temp.arg.nontype]p1.
bool Sema::CheckTemplateArgumentAddressOfObjectOrFunction(Expr *Arg,
NamedDecl *&Entity) {
bool Invalid = false;
// See through any implicit casts we added to fix the type.
if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
Arg = Cast->getSubExpr();
// C++ [temp.arg.nontype]p1:
//
// A template-argument for a non-type, non-template
// template-parameter shall be one of: [...]
//
// -- the address of an object or function with external
// linkage, including function templates and function
// template-ids but excluding non-static class members,
// expressed as & id-expression where the & is optional if
// the name refers to a function or array, or if the
// corresponding template-parameter is a reference; or
DeclRefExpr *DRE = 0;
// Ignore (and complain about) any excess parentheses.
while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
if (!Invalid) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_extra_parens)
<< Arg->getSourceRange();
Invalid = true;
}
Arg = Parens->getSubExpr();
}
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
if (UnOp->getOpcode() == UnaryOperator::AddrOf)
DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
} else
DRE = dyn_cast<DeclRefExpr>(Arg);
if (!DRE || !isa<ValueDecl>(DRE->getDecl()))
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_object_or_func_form)
<< Arg->getSourceRange();
// Cannot refer to non-static data members
if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl()))
return Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field)
<< Field << Arg->getSourceRange();
// Cannot refer to non-static member functions
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl()))
if (!Method->isStatic())
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_method)
<< Method << Arg->getSourceRange();
// Functions must have external linkage.
if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) {
if (Func->getStorageClass() == FunctionDecl::Static) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_function_not_extern)
<< Func << Arg->getSourceRange();
Diag(Func->getLocation(), diag::note_template_arg_internal_object)
<< true;
return true;
}
// Okay: we've named a function with external linkage.
Entity = Func;
return Invalid;
}
if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
if (!Var->hasGlobalStorage()) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_object_not_extern)
<< Var << Arg->getSourceRange();
Diag(Var->getLocation(), diag::note_template_arg_internal_object)
<< true;
return true;
}
// Okay: we've named an object with external linkage
Entity = Var;
return Invalid;
}
// We found something else, but we don't know specifically what it is.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_object_or_func)
<< Arg->getSourceRange();
Diag(DRE->getDecl()->getLocation(),
diag::note_template_arg_refers_here);
return true;
}
/// \brief Checks whether the given template argument is a pointer to
/// member constant according to C++ [temp.arg.nontype]p1.
bool
Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, NamedDecl *&Member) {
bool Invalid = false;
// See through any implicit casts we added to fix the type.
if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
Arg = Cast->getSubExpr();
// C++ [temp.arg.nontype]p1:
//
// A template-argument for a non-type, non-template
// template-parameter shall be one of: [...]
//
// -- a pointer to member expressed as described in 5.3.1.
QualifiedDeclRefExpr *DRE = 0;
// Ignore (and complain about) any excess parentheses.
while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
if (!Invalid) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_extra_parens)
<< Arg->getSourceRange();
Invalid = true;
}
Arg = Parens->getSubExpr();
}
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg))
if (UnOp->getOpcode() == UnaryOperator::AddrOf)
DRE = dyn_cast<QualifiedDeclRefExpr>(UnOp->getSubExpr());
if (!DRE)
return Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_pointer_to_member_form)
<< Arg->getSourceRange();
if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
assert((isa<FieldDecl>(DRE->getDecl()) ||
!cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
"Only non-static member pointers can make it here");
// Okay: this is the address of a non-static member, and therefore
// a member pointer constant.
Member = DRE->getDecl();
return Invalid;
}
// We found something else, but we don't know specifically what it is.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_pointer_to_member_form)
<< Arg->getSourceRange();
Diag(DRE->getDecl()->getLocation(),
diag::note_template_arg_refers_here);
return true;
}
/// \brief Check a template argument against its corresponding
/// non-type template parameter.
///
/// This routine implements the semantics of C++ [temp.arg.nontype].
/// It returns true if an error occurred, and false otherwise.
///
/// If Converted is non-NULL and no errors occur, the value
/// of this argument will be added to the end of the Converted vector.
bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
Expr *&Arg,
llvm::SmallVectorImpl<TemplateArgument> *Converted) {
// 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 (Param->getType()->isDependentType() || Arg->isTypeDependent())
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 = Param->getType();
QualType ArgType = Arg->getType();
if (ParamType->isIntegralType() || ParamType->isEnumeralType()) {
// C++ [temp.arg.nontype]p1:
// A template-argument for a non-type, non-template
// template-parameter shall be one of:
//
// -- an integral constant-expression of integral or enumeration
// type; or
// -- the name of a non-type template-parameter; or
SourceLocation NonConstantLoc;
llvm::APSInt Value;
if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) {
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_integral_or_enumeral)
<< ArgType << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
} else if (!Arg->isValueDependent() &&
!Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) {
Diag(NonConstantLoc, diag::err_template_arg_not_ice)
<< ArgType << Arg->getSourceRange();
return true;
}
// FIXME: We need some way to more easily get the unqualified form
// of the types without going all the way to the
// canonical type.
if (Context.getCanonicalType(ParamType).getCVRQualifiers())
ParamType = Context.getCanonicalType(ParamType).getUnqualifiedType();
if (Context.getCanonicalType(ArgType).getCVRQualifiers())
ArgType = Context.getCanonicalType(ArgType).getUnqualifiedType();
// Try to convert the argument to the parameter's type.
if (ParamType == ArgType) {
// Okay: no conversion necessary
} else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
!ParamType->isEnumeralType()) {
// This is an integral promotion or conversion.
ImpCastExprToType(Arg, ParamType);
} else {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << Param->getType() << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
// FIXME: Check overflow of template arguments?
if (Converted) {
// Add the value of this argument to the list of converted
// arguments. We use the bitwidth and signedness of the template
// parameter.
QualType IntegerType = Context.getCanonicalType(ParamType);
if (const EnumType *Enum = IntegerType->getAsEnumType())
IntegerType = Enum->getDecl()->getIntegerType();
llvm::APInt CanonicalArg(Context.getTypeSize(IntegerType), 0,
IntegerType->isSignedIntegerType());
CanonicalArg = Value;
Converted->push_back(TemplateArgument(CanonicalArg));
}
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).
(ParamType->isPointerType() &&
ParamType->getAsPointerType()->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->getAsReferenceType()->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).
(ParamType->isMemberPointerType() &&
ParamType->getAsMemberPointerType()->getPointeeType()
->isFunctionType())) {
if (Context.hasSameUnqualifiedType(ArgType,
ParamType.getNonReferenceType())) {
// We don't have to do anything: the types already match.
} else if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(ArgType);
ImpCastExprToType(Arg, ArgType);
} else if (FunctionDecl *Fn
= ResolveAddressOfOverloadedFunction(Arg, ParamType, true)) {
if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
return true;
FixOverloadedFunctionReference(Arg, Fn);
ArgType = Arg->getType();
if (ArgType->isFunctionType() && ParamType->isPointerType()) {
ArgType = Context.getPointerType(Arg->getType());
ImpCastExprToType(Arg, ArgType);
}
}
if (!Context.hasSameUnqualifiedType(ArgType,
ParamType.getNonReferenceType())) {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << Param->getType() << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
if (ParamType->isMemberPointerType()) {
NamedDecl *Member = 0;
if (CheckTemplateArgumentPointerToMember(Arg, Member))
return true;
if (Converted)
Converted->push_back(TemplateArgument(Member));
return false;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Converted)
Converted->push_back(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.
assert(ParamType->getAsPointerType()->getPointeeType()->isObjectType() &&
"Only object pointers allowed here");
if (ArgType->isArrayType()) {
ArgType = Context.getArrayDecayedType(ArgType);
ImpCastExprToType(Arg, ArgType);
}
if (IsQualificationConversion(ArgType, ParamType)) {
ArgType = ParamType;
ImpCastExprToType(Arg, ParamType);
}
if (!Context.hasSameUnqualifiedType(ArgType, ParamType)) {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << Param->getType() << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Converted)
Converted->push_back(TemplateArgument(Entity));
return false;
}
if (const ReferenceType *ParamRefType = ParamType->getAsReferenceType()) {
// -- 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)
<< Param->getType() << 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)
<< Param->getType() << Arg->getType()
<< Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Entity = 0;
if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity))
return true;
if (Converted)
Converted->push_back(TemplateArgument(Entity));
return false;
}
// -- For a non-type template-parameter of type pointer to data
// member, qualification conversions (4.4) are applied.
assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
if (Context.hasSameUnqualifiedType(ParamType, ArgType)) {
// Types match exactly: nothing more to do here.
} else if (IsQualificationConversion(ArgType, ParamType)) {
ImpCastExprToType(Arg, ParamType);
} else {
// We can't perform this conversion.
Diag(Arg->getSourceRange().getBegin(),
diag::err_template_arg_not_convertible)
<< Arg->getType() << Param->getType() << Arg->getSourceRange();
Diag(Param->getLocation(), diag::note_template_param_here);
return true;
}
NamedDecl *Member = 0;
if (CheckTemplateArgumentPointerToMember(Arg, Member))
return true;
if (Converted)
Converted->push_back(TemplateArgument(Member));
return false;
}
/// \brief Check a template argument against its corresponding
/// template template parameter.
///
/// This routine implements the semantics of C++ [temp.arg.template].
/// It returns true if an error occurred, and false otherwise.
bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
DeclRefExpr *Arg) {
assert(isa<TemplateDecl>(Arg->getDecl()) && "Only template decls allowed");
TemplateDecl *Template = cast<TemplateDecl>(Arg->getDecl());
// C++ [temp.arg.template]p1:
// A template-argument for a template template-parameter shall be
// the name of a class template, expressed as id-expression. Only
// primary class templates are considered when matching the
// template template argument with the corresponding parameter;
// partial specializations are not considered even if their
// parameter lists match that of the template template parameter.
if (!isa<ClassTemplateDecl>(Template)) {
assert(isa<FunctionTemplateDecl>(Template) &&
"Only function templates are possible here");
Diag(Arg->getSourceRange().getBegin(),
diag::note_template_arg_refers_here_func)
<< Template;
}
return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
Param->getTemplateParameters(),
true, true,
Arg->getSourceRange().getBegin());
}
/// \brief Determine whether the given template parameter lists are
/// equivalent.
///
/// \param New The new template parameter list, typically written in the
/// source code as part of a new template declaration.
///
/// \param Old The old template parameter list, typically found via
/// name lookup of the template declared with this template parameter
/// list.
///
/// \param Complain If true, this routine will produce a diagnostic if
/// the template parameter lists are not equivalent.
///
/// \param IsTemplateTemplateParm If true, this routine is being
/// called to compare the template parameter lists of a template
/// template parameter.
///
/// \param TemplateArgLoc If this source location is valid, then we
/// are actually checking the template parameter list of a template
/// argument (New) against the template parameter list of its
/// corresponding template template parameter (Old). We produce
/// slightly different diagnostics in this scenario.
///
/// \returns True if the template parameter lists are equal, false
/// otherwise.
bool
Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
TemplateParameterList *Old,
bool Complain,
bool IsTemplateTemplateParm,
SourceLocation TemplateArgLoc) {
if (Old->size() != New->size()) {
if (Complain) {
unsigned NextDiag = diag::err_template_param_list_different_arity;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_param_list_different_arity;
}
Diag(New->getTemplateLoc(), NextDiag)
<< (New->size() > Old->size())
<< IsTemplateTemplateParm
<< SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
<< IsTemplateTemplateParm
<< SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
}
return false;
}
for (TemplateParameterList::iterator OldParm = Old->begin(),
OldParmEnd = Old->end(), NewParm = New->begin();
OldParm != OldParmEnd; ++OldParm, ++NewParm) {
if ((*OldParm)->getKind() != (*NewParm)->getKind()) {
unsigned NextDiag = diag::err_template_param_different_kind;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_param_different_kind;
}
Diag((*NewParm)->getLocation(), NextDiag)
<< IsTemplateTemplateParm;
Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration)
<< IsTemplateTemplateParm;
return false;
}
if (isa<TemplateTypeParmDecl>(*OldParm)) {
// Okay; all template type parameters are equivalent (since we
// know we're at the same index).
#if 0
// FIXME: Enable this code in debug mode *after* we properly go
// through and "instantiate" the template parameter lists of
// template template parameters. It's only after this
// instantiation that (1) any dependent types within the
// template parameter list of the template template parameter
// can be checked, and (2) the template type parameter depths
// will match up.
QualType OldParmType
= Context.getTypeDeclType(cast<TemplateTypeParmDecl>(*OldParm));
QualType NewParmType
= Context.getTypeDeclType(cast<TemplateTypeParmDecl>(*NewParm));
assert(Context.getCanonicalType(OldParmType) ==
Context.getCanonicalType(NewParmType) &&
"type parameter mismatch?");
#endif
} else if (NonTypeTemplateParmDecl *OldNTTP
= dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
// The types of non-type template parameters must agree.
NonTypeTemplateParmDecl *NewNTTP
= cast<NonTypeTemplateParmDecl>(*NewParm);
if (Context.getCanonicalType(OldNTTP->getType()) !=
Context.getCanonicalType(NewNTTP->getType())) {
if (Complain) {
unsigned NextDiag = diag::err_template_nontype_parm_different_type;
if (TemplateArgLoc.isValid()) {
Diag(TemplateArgLoc,
diag::err_template_arg_template_params_mismatch);
NextDiag = diag::note_template_nontype_parm_different_type;
}
Diag(NewNTTP->getLocation(), NextDiag)
<< NewNTTP->getType()
<< IsTemplateTemplateParm;
Diag(OldNTTP->getLocation(),
diag::note_template_nontype_parm_prev_declaration)
<< OldNTTP->getType();
}
return false;
}
} else {
// The template parameter lists of template template
// parameters must agree.
// FIXME: Could we perform a faster "type" comparison here?
assert(isa<TemplateTemplateParmDecl>(*OldParm) &&
"Only template template parameters handled here");
TemplateTemplateParmDecl *OldTTP
= cast<TemplateTemplateParmDecl>(*OldParm);
TemplateTemplateParmDecl *NewTTP
= cast<TemplateTemplateParmDecl>(*NewParm);
if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
OldTTP->getTemplateParameters(),
Complain,
/*IsTemplateTemplateParm=*/true,
TemplateArgLoc))
return false;
}
}
return true;
}
/// \brief Check whether a template can be declared within this scope.
///
/// If the template declaration is valid in this scope, returns
/// false. Otherwise, issues a diagnostic and returns true.
bool
Sema::CheckTemplateDeclScope(Scope *S,
MultiTemplateParamsArg &TemplateParameterLists) {
assert(TemplateParameterLists.size() > 0 && "Not a template");
// Find the nearest enclosing declaration scope.
while ((S->getFlags() & Scope::DeclScope) == 0 ||
(S->getFlags() & Scope::TemplateParamScope) != 0)
S = S->getParent();
TemplateParameterList *TemplateParams =
static_cast<TemplateParameterList*>(*TemplateParameterLists.get());
SourceLocation TemplateLoc = TemplateParams->getTemplateLoc();
SourceRange TemplateRange
= SourceRange(TemplateLoc, TemplateParams->getRAngleLoc());
// C++ [temp]p2:
// A template-declaration can appear only as a namespace scope or
// class scope declaration.
DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
while (Ctx && isa<LinkageSpecDecl>(Ctx)) {
if (cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
return Diag(TemplateLoc, diag::err_template_linkage)
<< TemplateRange;
Ctx = Ctx->getParent();
}
if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
return false;
return Diag(TemplateLoc, diag::err_template_outside_namespace_or_class_scope)
<< TemplateRange;
}
/// \brief Check whether a class template specialization in the
/// current context is well-formed.
///
/// This routine determines whether a class template specialization
/// can be declared in the current context (C++ [temp.expl.spec]p2)
/// and emits appropriate diagnostics if there was an error. It
/// returns true if there was an error that we cannot recover from,
/// and false otherwise.
bool
Sema::CheckClassTemplateSpecializationScope(ClassTemplateDecl *ClassTemplate,
ClassTemplateSpecializationDecl *PrevDecl,
SourceLocation TemplateNameLoc,
SourceRange ScopeSpecifierRange) {
// C++ [temp.expl.spec]p2:
// An explicit specialization shall be declared in the namespace
// of which the template is a member, or, for member templates, in
// the namespace of which the enclosing class or enclosing class
// template is a member. An explicit specialization of a member
// function, member class or static data member of a class
// template shall be declared in the namespace of which the class
// template is a member. Such a declaration may also be a
// definition. If the declaration is not a definition, the
// specialization may be defined later in the name- space in which
// the explicit specialization was declared, or in a namespace
// that encloses the one in which the explicit specialization was
// declared.
if (CurContext->getLookupContext()->isFunctionOrMethod()) {
Diag(TemplateNameLoc, diag::err_template_spec_decl_function_scope)
<< ClassTemplate;
return true;
}
DeclContext *DC = CurContext->getEnclosingNamespaceContext();
DeclContext *TemplateContext
= ClassTemplate->getDeclContext()->getEnclosingNamespaceContext();
if (!PrevDecl || PrevDecl->getSpecializationKind() == TSK_Undeclared) {
// There is no prior declaration of this entity, so this
// specialization must be in the same context as the template
// itself.
if (DC != TemplateContext) {
if (isa<TranslationUnitDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_decl_out_of_scope_global)
<< ClassTemplate << ScopeSpecifierRange;
else if (isa<NamespaceDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_decl_out_of_scope)
<< ClassTemplate << cast<NamedDecl>(TemplateContext)
<< ScopeSpecifierRange;
Diag(ClassTemplate->getLocation(), diag::note_template_decl_here);
}
return false;
}
// We have a previous declaration of this entity. Make sure that
// this redeclaration (or definition) occurs in an enclosing namespace.
if (!CurContext->Encloses(TemplateContext)) {
if (isa<TranslationUnitDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_redecl_global_scope)
<< ClassTemplate << ScopeSpecifierRange;
else if (isa<NamespaceDecl>(TemplateContext))
Diag(TemplateNameLoc, diag::err_template_spec_redecl_out_of_scope)
<< ClassTemplate << cast<NamedDecl>(TemplateContext)
<< ScopeSpecifierRange;
Diag(ClassTemplate->getLocation(), diag::note_template_decl_here);
}
return false;
}
Sema::DeclTy *
Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, TagKind TK,
SourceLocation KWLoc,
const CXXScopeSpec &SS,
DeclTy *TemplateD,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
ASTTemplateArgsPtr TemplateArgs,
SourceLocation *TemplateArgLocs,
SourceLocation RAngleLoc,
AttributeList *Attr,
MultiTemplateParamsArg TemplateParameterLists) {
// Find the class template we're specializing
ClassTemplateDecl *ClassTemplate
= dyn_cast_or_null<ClassTemplateDecl>(static_cast<Decl *>(TemplateD));
if (!ClassTemplate)
return 0;
// Check the validity of the template headers that introduce this
// template.
// FIXME: Once we have member templates, we'll need to check
// C++ [temp.expl.spec]p17-18, where we could have multiple levels of
// template<> headers.
if (TemplateParameterLists.size() == 0)
Diag(KWLoc, diag::err_template_spec_needs_header)
<< CodeModificationHint::CreateInsertion(KWLoc, "template<> ");
else {
TemplateParameterList *TemplateParams
= static_cast<TemplateParameterList*>(*TemplateParameterLists.get());
if (TemplateParameterLists.size() > 1) {
Diag(TemplateParams->getTemplateLoc(),
diag::err_template_spec_extra_headers);
return 0;
}
if (TemplateParams->size() > 0) {
// FIXME: No support for class template partial specialization.
Diag(TemplateParams->getTemplateLoc(),
diag::unsup_template_partial_spec);
return 0;
}
}
// 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 (ClassTemplate->getTemplatedDecl()->getTagKind() != Kind) {
Diag(KWLoc, diag::err_use_with_wrong_tag) << ClassTemplate;
Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
diag::note_previous_use);
Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
}
// Check that the template argument list is well-formed for this
// template.
llvm::SmallVector<TemplateArgument, 16> ConvertedTemplateArgs;
if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, LAngleLoc,
TemplateArgs, TemplateArgLocs, RAngleLoc,
ConvertedTemplateArgs))
return 0;
assert((ConvertedTemplateArgs.size() ==
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, &ConvertedTemplateArgs[0],
ConvertedTemplateArgs.size());
void *InsertPos = 0;
ClassTemplateSpecializationDecl *PrevDecl
= ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
ClassTemplateSpecializationDecl *Specialization = 0;
// Check whether we can declare a class template specialization in
// the current scope.
if (CheckClassTemplateSpecializationScope(ClassTemplate, PrevDecl,
TemplateNameLoc,
SS.getRange()))
return 0;
if (PrevDecl && PrevDecl->getSpecializationKind() == TSK_Undeclared) {
// Since the only prior class template specialization with these
// arguments was referenced but not declared, reuse that
// declaration node as our own, updating its source location to
// reflect our new declaration.
Specialization = PrevDecl;
Specialization->setLocation(TemplateNameLoc);
PrevDecl = 0;
} else {
// Create a new class template specialization declaration node for
// this explicit specialization.
Specialization
= ClassTemplateSpecializationDecl::Create(Context,
ClassTemplate->getDeclContext(),
TemplateNameLoc,
ClassTemplate,
&ConvertedTemplateArgs[0],
ConvertedTemplateArgs.size(),
PrevDecl);
if (PrevDecl) {
ClassTemplate->getSpecializations().RemoveNode(PrevDecl);
ClassTemplate->getSpecializations().GetOrInsertNode(Specialization);
} else {
ClassTemplate->getSpecializations().InsertNode(Specialization,
InsertPos);
}
}
// Note that this is an explicit specialization.
Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
// Check that this isn't a redefinition of this specialization.
if (TK == TK_Definition) {
if (RecordDecl *Def = Specialization->getDefinition(Context)) {
// FIXME: Should also handle explicit specialization after
// implicit instantiation with a special diagnostic.
SourceRange Range(TemplateNameLoc, RAngleLoc);
Diag(TemplateNameLoc, diag::err_redefinition)
<< Specialization << Range;
Diag(Def->getLocation(), diag::note_previous_definition);
Specialization->setInvalidDecl();
return 0;
}
}
// 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.
Specialization->setTypeAsWritten(
Context.getClassTemplateSpecializationType(ClassTemplate,
TemplateArgs.size(),
reinterpret_cast<uintptr_t *>(TemplateArgs.getArgs()),
TemplateArgs.getArgIsType(),
Context.getTypeDeclType(Specialization)));
TemplateArgs.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 (TK == TK_Definition)
Specialization->startDefinition();
// Add the specialization into its lexical context, so that it can
// be seen when iterating through the list of declarations in that
// context. However, specializations are not found by name lookup.
CurContext->addDecl(Specialization);
return Specialization;
}