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llvm / llvm-project / clang / refs/heads/main / . / lib / Sema / SemaTemplateInstantiateDecl.cpp
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//===--- SemaTemplateInstantiateDecl.cpp - C++ Template Decl Instantiation ===/
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//===----------------------------------------------------------------------===/
//
// This file implements C++ template instantiation for declarations.
//
//===----------------------------------------------------------------------===/
#include "TreeTransform.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTMutationListener.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/DeclVisitor.h"
#include "clang/AST/DependentDiagnostic.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/PrettyDeclStackTrace.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Sema/EnterExpressionEvaluationContext.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/SemaCUDA.h"
#include "clang/Sema/SemaInternal.h"
#include "clang/Sema/SemaOpenMP.h"
#include "clang/Sema/Template.h"
#include "clang/Sema/TemplateInstCallback.h"
#include "llvm/Support/TimeProfiler.h"
#include <optional>
using namespace clang;
static bool isDeclWithinFunction(const Decl *D) {
const DeclContext *DC = D->getDeclContext();
if (DC->isFunctionOrMethod())
return true;
if (DC->isRecord())
return cast<CXXRecordDecl>(DC)->isLocalClass();
return false;
}
template<typename DeclT>
static bool SubstQualifier(Sema &SemaRef, const DeclT *OldDecl, DeclT *NewDecl,
const MultiLevelTemplateArgumentList &TemplateArgs) {
if (!OldDecl->getQualifierLoc())
return false;
assert((NewDecl->getFriendObjectKind() ||
!OldDecl->getLexicalDeclContext()->isDependentContext()) &&
"non-friend with qualified name defined in dependent context");
Sema::ContextRAII SavedContext(
SemaRef,
const_cast<DeclContext *>(NewDecl->getFriendObjectKind()
? NewDecl->getLexicalDeclContext()
: OldDecl->getLexicalDeclContext()));
NestedNameSpecifierLoc NewQualifierLoc
= SemaRef.SubstNestedNameSpecifierLoc(OldDecl->getQualifierLoc(),
TemplateArgs);
if (!NewQualifierLoc)
return true;
NewDecl->setQualifierInfo(NewQualifierLoc);
return false;
}
bool TemplateDeclInstantiator::SubstQualifier(const DeclaratorDecl *OldDecl,
DeclaratorDecl *NewDecl) {
return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
}
bool TemplateDeclInstantiator::SubstQualifier(const TagDecl *OldDecl,
TagDecl *NewDecl) {
return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
}
// Include attribute instantiation code.
#include "clang/Sema/AttrTemplateInstantiate.inc"
static void instantiateDependentAlignedAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AlignedAttr *Aligned, Decl *New, bool IsPackExpansion) {
if (Aligned->isAlignmentExpr()) {
// The alignment expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(Aligned->getAlignmentExpr(), TemplateArgs);
if (!Result.isInvalid())
S.AddAlignedAttr(New, *Aligned, Result.getAs<Expr>(), IsPackExpansion);
} else {
if (TypeSourceInfo *Result =
S.SubstType(Aligned->getAlignmentType(), TemplateArgs,
Aligned->getLocation(), DeclarationName())) {
if (!S.CheckAlignasTypeArgument(Aligned->getSpelling(), Result,
Aligned->getLocation(),
Result->getTypeLoc().getSourceRange()))
S.AddAlignedAttr(New, *Aligned, Result, IsPackExpansion);
}
}
}
static void instantiateDependentAlignedAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AlignedAttr *Aligned, Decl *New) {
if (!Aligned->isPackExpansion()) {
instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
return;
}
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
if (Aligned->isAlignmentExpr())
S.collectUnexpandedParameterPacks(Aligned->getAlignmentExpr(),
Unexpanded);
else
S.collectUnexpandedParameterPacks(Aligned->getAlignmentType()->getTypeLoc(),
Unexpanded);
assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
// Determine whether we can expand this attribute pack yet.
bool Expand = true, RetainExpansion = false;
std::optional<unsigned> NumExpansions;
// FIXME: Use the actual location of the ellipsis.
SourceLocation EllipsisLoc = Aligned->getLocation();
if (S.CheckParameterPacksForExpansion(EllipsisLoc, Aligned->getRange(),
Unexpanded, TemplateArgs, Expand,
RetainExpansion, NumExpansions))
return;
if (!Expand) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, -1);
instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, true);
} else {
for (unsigned I = 0; I != *NumExpansions; ++I) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, I);
instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
}
}
}
static void instantiateDependentAssumeAlignedAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AssumeAlignedAttr *Aligned, Decl *New) {
// The alignment expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
Expr *E, *OE = nullptr;
ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
if (Result.isInvalid())
return;
E = Result.getAs<Expr>();
if (Aligned->getOffset()) {
Result = S.SubstExpr(Aligned->getOffset(), TemplateArgs);
if (Result.isInvalid())
return;
OE = Result.getAs<Expr>();
}
S.AddAssumeAlignedAttr(New, *Aligned, E, OE);
}
static void instantiateDependentAlignValueAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AlignValueAttr *Aligned, Decl *New) {
// The alignment expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
if (!Result.isInvalid())
S.AddAlignValueAttr(New, *Aligned, Result.getAs<Expr>());
}
static void instantiateDependentAllocAlignAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AllocAlignAttr *Align, Decl *New) {
Expr *Param = IntegerLiteral::Create(
S.getASTContext(),
llvm::APInt(64, Align->getParamIndex().getSourceIndex()),
S.getASTContext().UnsignedLongLongTy, Align->getLocation());
S.AddAllocAlignAttr(New, *Align, Param);
}
static void instantiateDependentAnnotationAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AnnotateAttr *Attr, Decl *New) {
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
// If the attribute has delayed arguments it will have to instantiate those
// and handle them as new arguments for the attribute.
bool HasDelayedArgs = Attr->delayedArgs_size();
ArrayRef<Expr *> ArgsToInstantiate =
HasDelayedArgs
? ArrayRef<Expr *>{Attr->delayedArgs_begin(), Attr->delayedArgs_end()}
: ArrayRef<Expr *>{Attr->args_begin(), Attr->args_end()};
SmallVector<Expr *, 4> Args;
if (S.SubstExprs(ArgsToInstantiate,
/*IsCall=*/false, TemplateArgs, Args))
return;
StringRef Str = Attr->getAnnotation();
if (HasDelayedArgs) {
if (Args.size() < 1) {
S.Diag(Attr->getLoc(), diag::err_attribute_too_few_arguments)
<< Attr << 1;
return;
}
if (!S.checkStringLiteralArgumentAttr(*Attr, Args[0], Str))
return;
llvm::SmallVector<Expr *, 4> ActualArgs;
ActualArgs.insert(ActualArgs.begin(), Args.begin() + 1, Args.end());
std::swap(Args, ActualArgs);
}
S.AddAnnotationAttr(New, *Attr, Str, Args);
}
static Expr *instantiateDependentFunctionAttrCondition(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const Attr *A, Expr *OldCond, const Decl *Tmpl, FunctionDecl *New) {
Expr *Cond = nullptr;
{
Sema::ContextRAII SwitchContext(S, New);
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(OldCond, TemplateArgs);
if (Result.isInvalid())
return nullptr;
Cond = Result.getAs<Expr>();
}
if (!Cond->isTypeDependent()) {
ExprResult Converted = S.PerformContextuallyConvertToBool(Cond);
if (Converted.isInvalid())
return nullptr;
Cond = Converted.get();
}
SmallVector<PartialDiagnosticAt, 8> Diags;
if (OldCond->isValueDependent() && !Cond->isValueDependent() &&
!Expr::isPotentialConstantExprUnevaluated(Cond, New, Diags)) {
S.Diag(A->getLocation(), diag::err_attr_cond_never_constant_expr) << A;
for (const auto &P : Diags)
S.Diag(P.first, P.second);
return nullptr;
}
return Cond;
}
static void instantiateDependentEnableIfAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const EnableIfAttr *EIA, const Decl *Tmpl, FunctionDecl *New) {
Expr *Cond = instantiateDependentFunctionAttrCondition(
S, TemplateArgs, EIA, EIA->getCond(), Tmpl, New);
if (Cond)
New->addAttr(new (S.getASTContext()) EnableIfAttr(S.getASTContext(), *EIA,
Cond, EIA->getMessage()));
}
static void instantiateDependentDiagnoseIfAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const DiagnoseIfAttr *DIA, const Decl *Tmpl, FunctionDecl *New) {
Expr *Cond = instantiateDependentFunctionAttrCondition(
S, TemplateArgs, DIA, DIA->getCond(), Tmpl, New);
if (Cond)
New->addAttr(new (S.getASTContext()) DiagnoseIfAttr(
S.getASTContext(), *DIA, Cond, DIA->getMessage(),
DIA->getDiagnosticType(), DIA->getArgDependent(), New));
}
// Constructs and adds to New a new instance of CUDALaunchBoundsAttr using
// template A as the base and arguments from TemplateArgs.
static void instantiateDependentCUDALaunchBoundsAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const CUDALaunchBoundsAttr &Attr, Decl *New) {
// The alignment expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(Attr.getMaxThreads(), TemplateArgs);
if (Result.isInvalid())
return;
Expr *MaxThreads = Result.getAs<Expr>();
Expr *MinBlocks = nullptr;
if (Attr.getMinBlocks()) {
Result = S.SubstExpr(Attr.getMinBlocks(), TemplateArgs);
if (Result.isInvalid())
return;
MinBlocks = Result.getAs<Expr>();
}
Expr *MaxBlocks = nullptr;
if (Attr.getMaxBlocks()) {
Result = S.SubstExpr(Attr.getMaxBlocks(), TemplateArgs);
if (Result.isInvalid())
return;
MaxBlocks = Result.getAs<Expr>();
}
S.AddLaunchBoundsAttr(New, Attr, MaxThreads, MinBlocks, MaxBlocks);
}
static void
instantiateDependentModeAttr(Sema &S,
const MultiLevelTemplateArgumentList &TemplateArgs,
const ModeAttr &Attr, Decl *New) {
S.AddModeAttr(New, Attr, Attr.getMode(),
/*InInstantiation=*/true);
}
/// Instantiation of 'declare simd' attribute and its arguments.
static void instantiateOMPDeclareSimdDeclAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const OMPDeclareSimdDeclAttr &Attr, Decl *New) {
// Allow 'this' in clauses with varlists.
if (auto *FTD = dyn_cast<FunctionTemplateDecl>(New))
New = FTD->getTemplatedDecl();
auto *FD = cast<FunctionDecl>(New);
auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(FD->getDeclContext());
SmallVector<Expr *, 4> Uniforms, Aligneds, Alignments, Linears, Steps;
SmallVector<unsigned, 4> LinModifiers;
auto SubstExpr = [&](Expr *E) -> ExprResult {
if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()))
if (auto *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
Sema::ContextRAII SavedContext(S, FD);
LocalInstantiationScope Local(S);
if (FD->getNumParams() > PVD->getFunctionScopeIndex())
Local.InstantiatedLocal(
PVD, FD->getParamDecl(PVD->getFunctionScopeIndex()));
return S.SubstExpr(E, TemplateArgs);
}
Sema::CXXThisScopeRAII ThisScope(S, ThisContext, Qualifiers(),
FD->isCXXInstanceMember());
return S.SubstExpr(E, TemplateArgs);
};
// Substitute a single OpenMP clause, which is a potentially-evaluated
// full-expression.
auto Subst = [&](Expr *E) -> ExprResult {
EnterExpressionEvaluationContext Evaluated(
S, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
ExprResult Res = SubstExpr(E);
if (Res.isInvalid())
return Res;
return S.ActOnFinishFullExpr(Res.get(), false);
};
ExprResult Simdlen;
if (auto *E = Attr.getSimdlen())
Simdlen = Subst(E);
if (Attr.uniforms_size() > 0) {
for(auto *E : Attr.uniforms()) {
ExprResult Inst = Subst(E);
if (Inst.isInvalid())
continue;
Uniforms.push_back(Inst.get());
}
}
auto AI = Attr.alignments_begin();
for (auto *E : Attr.aligneds()) {
ExprResult Inst = Subst(E);
if (Inst.isInvalid())
continue;
Aligneds.push_back(Inst.get());
Inst = ExprEmpty();
if (*AI)
Inst = S.SubstExpr(*AI, TemplateArgs);
Alignments.push_back(Inst.get());
++AI;
}
auto SI = Attr.steps_begin();
for (auto *E : Attr.linears()) {
ExprResult Inst = Subst(E);
if (Inst.isInvalid())
continue;
Linears.push_back(Inst.get());
Inst = ExprEmpty();
if (*SI)
Inst = S.SubstExpr(*SI, TemplateArgs);
Steps.push_back(Inst.get());
++SI;
}
LinModifiers.append(Attr.modifiers_begin(), Attr.modifiers_end());
(void)S.OpenMP().ActOnOpenMPDeclareSimdDirective(
S.ConvertDeclToDeclGroup(New), Attr.getBranchState(), Simdlen.get(),
Uniforms, Aligneds, Alignments, Linears, LinModifiers, Steps,
Attr.getRange());
}
/// Instantiation of 'declare variant' attribute and its arguments.
static void instantiateOMPDeclareVariantAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const OMPDeclareVariantAttr &Attr, Decl *New) {
// Allow 'this' in clauses with varlists.
if (auto *FTD = dyn_cast<FunctionTemplateDecl>(New))
New = FTD->getTemplatedDecl();
auto *FD = cast<FunctionDecl>(New);
auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(FD->getDeclContext());
auto &&SubstExpr = [FD, ThisContext, &S, &TemplateArgs](Expr *E) {
if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()))
if (auto *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
Sema::ContextRAII SavedContext(S, FD);
LocalInstantiationScope Local(S);
if (FD->getNumParams() > PVD->getFunctionScopeIndex())
Local.InstantiatedLocal(
PVD, FD->getParamDecl(PVD->getFunctionScopeIndex()));
return S.SubstExpr(E, TemplateArgs);
}
Sema::CXXThisScopeRAII ThisScope(S, ThisContext, Qualifiers(),
FD->isCXXInstanceMember());
return S.SubstExpr(E, TemplateArgs);
};
// Substitute a single OpenMP clause, which is a potentially-evaluated
// full-expression.
auto &&Subst = [&SubstExpr, &S](Expr *E) {
EnterExpressionEvaluationContext Evaluated(
S, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
ExprResult Res = SubstExpr(E);
if (Res.isInvalid())
return Res;
return S.ActOnFinishFullExpr(Res.get(), false);
};
ExprResult VariantFuncRef;
if (Expr *E = Attr.getVariantFuncRef()) {
// Do not mark function as is used to prevent its emission if this is the
// only place where it is used.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
VariantFuncRef = Subst(E);
}
// Copy the template version of the OMPTraitInfo and run substitute on all
// score and condition expressiosn.
OMPTraitInfo &TI = S.getASTContext().getNewOMPTraitInfo();
TI = *Attr.getTraitInfos();
// Try to substitute template parameters in score and condition expressions.
auto SubstScoreOrConditionExpr = [&S, Subst](Expr *&E, bool) {
if (E) {
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult ER = Subst(E);
if (ER.isUsable())
E = ER.get();
else
return true;
}
return false;
};
if (TI.anyScoreOrCondition(SubstScoreOrConditionExpr))
return;
Expr *E = VariantFuncRef.get();
// Check function/variant ref for `omp declare variant` but not for `omp
// begin declare variant` (which use implicit attributes).
std::optional<std::pair<FunctionDecl *, Expr *>> DeclVarData =
S.OpenMP().checkOpenMPDeclareVariantFunction(
S.ConvertDeclToDeclGroup(New), E, TI, Attr.appendArgs_size(),
Attr.getRange());
if (!DeclVarData)
return;
E = DeclVarData->second;
FD = DeclVarData->first;
if (auto *VariantDRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts())) {
if (auto *VariantFD = dyn_cast<FunctionDecl>(VariantDRE->getDecl())) {
if (auto *VariantFTD = VariantFD->getDescribedFunctionTemplate()) {
if (!VariantFTD->isThisDeclarationADefinition())
return;
Sema::TentativeAnalysisScope Trap(S);
const TemplateArgumentList *TAL = TemplateArgumentList::CreateCopy(
S.Context, TemplateArgs.getInnermost());
auto *SubstFD = S.InstantiateFunctionDeclaration(VariantFTD, TAL,
New->getLocation());
if (!SubstFD)
return;
QualType NewType = S.Context.mergeFunctionTypes(
SubstFD->getType(), FD->getType(),
/* OfBlockPointer */ false,
/* Unqualified */ false, /* AllowCXX */ true);
if (NewType.isNull())
return;
S.InstantiateFunctionDefinition(
New->getLocation(), SubstFD, /* Recursive */ true,
/* DefinitionRequired */ false, /* AtEndOfTU */ false);
SubstFD->setInstantiationIsPending(!SubstFD->isDefined());
E = DeclRefExpr::Create(S.Context, NestedNameSpecifierLoc(),
SourceLocation(), SubstFD,
/* RefersToEnclosingVariableOrCapture */ false,
/* NameLoc */ SubstFD->getLocation(),
SubstFD->getType(), ExprValueKind::VK_PRValue);
}
}
}
SmallVector<Expr *, 8> NothingExprs;
SmallVector<Expr *, 8> NeedDevicePtrExprs;
SmallVector<OMPInteropInfo, 4> AppendArgs;
for (Expr *E : Attr.adjustArgsNothing()) {
ExprResult ER = Subst(E);
if (ER.isInvalid())
continue;
NothingExprs.push_back(ER.get());
}
for (Expr *E : Attr.adjustArgsNeedDevicePtr()) {
ExprResult ER = Subst(E);
if (ER.isInvalid())
continue;
NeedDevicePtrExprs.push_back(ER.get());
}
for (OMPInteropInfo &II : Attr.appendArgs()) {
// When prefer_type is implemented for append_args handle them here too.
AppendArgs.emplace_back(II.IsTarget, II.IsTargetSync);
}
S.OpenMP().ActOnOpenMPDeclareVariantDirective(
FD, E, TI, NothingExprs, NeedDevicePtrExprs, AppendArgs, SourceLocation(),
SourceLocation(), Attr.getRange());
}
static void instantiateDependentAMDGPUFlatWorkGroupSizeAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AMDGPUFlatWorkGroupSizeAttr &Attr, Decl *New) {
// Both min and max expression are constant expressions.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(Attr.getMin(), TemplateArgs);
if (Result.isInvalid())
return;
Expr *MinExpr = Result.getAs<Expr>();
Result = S.SubstExpr(Attr.getMax(), TemplateArgs);
if (Result.isInvalid())
return;
Expr *MaxExpr = Result.getAs<Expr>();
S.addAMDGPUFlatWorkGroupSizeAttr(New, Attr, MinExpr, MaxExpr);
}
ExplicitSpecifier Sema::instantiateExplicitSpecifier(
const MultiLevelTemplateArgumentList &TemplateArgs, ExplicitSpecifier ES) {
if (!ES.getExpr())
return ES;
Expr *OldCond = ES.getExpr();
Expr *Cond = nullptr;
{
EnterExpressionEvaluationContext Unevaluated(
*this, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult SubstResult = SubstExpr(OldCond, TemplateArgs);
if (SubstResult.isInvalid()) {
return ExplicitSpecifier::Invalid();
}
Cond = SubstResult.get();
}
ExplicitSpecifier Result(Cond, ES.getKind());
if (!Cond->isTypeDependent())
tryResolveExplicitSpecifier(Result);
return Result;
}
static void instantiateDependentAMDGPUWavesPerEUAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AMDGPUWavesPerEUAttr &Attr, Decl *New) {
// Both min and max expression are constant expressions.
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Result = S.SubstExpr(Attr.getMin(), TemplateArgs);
if (Result.isInvalid())
return;
Expr *MinExpr = Result.getAs<Expr>();
Expr *MaxExpr = nullptr;
if (auto Max = Attr.getMax()) {
Result = S.SubstExpr(Max, TemplateArgs);
if (Result.isInvalid())
return;
MaxExpr = Result.getAs<Expr>();
}
S.addAMDGPUWavesPerEUAttr(New, Attr, MinExpr, MaxExpr);
}
static void instantiateDependentAMDGPUMaxNumWorkGroupsAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const AMDGPUMaxNumWorkGroupsAttr &Attr, Decl *New) {
EnterExpressionEvaluationContext Unevaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult ResultX = S.SubstExpr(Attr.getMaxNumWorkGroupsX(), TemplateArgs);
if (!ResultX.isUsable())
return;
ExprResult ResultY = S.SubstExpr(Attr.getMaxNumWorkGroupsY(), TemplateArgs);
if (!ResultY.isUsable())
return;
ExprResult ResultZ = S.SubstExpr(Attr.getMaxNumWorkGroupsZ(), TemplateArgs);
if (!ResultZ.isUsable())
return;
Expr *XExpr = ResultX.getAs<Expr>();
Expr *YExpr = ResultY.getAs<Expr>();
Expr *ZExpr = ResultZ.getAs<Expr>();
S.addAMDGPUMaxNumWorkGroupsAttr(New, Attr, XExpr, YExpr, ZExpr);
}
// This doesn't take any template parameters, but we have a custom action that
// needs to happen when the kernel itself is instantiated. We need to run the
// ItaniumMangler to mark the names required to name this kernel.
static void instantiateDependentSYCLKernelAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const SYCLKernelAttr &Attr, Decl *New) {
New->addAttr(Attr.clone(S.getASTContext()));
}
/// Determine whether the attribute A might be relevant to the declaration D.
/// If not, we can skip instantiating it. The attribute may or may not have
/// been instantiated yet.
static bool isRelevantAttr(Sema &S, const Decl *D, const Attr *A) {
// 'preferred_name' is only relevant to the matching specialization of the
// template.
if (const auto *PNA = dyn_cast<PreferredNameAttr>(A)) {
QualType T = PNA->getTypedefType();
const auto *RD = cast<CXXRecordDecl>(D);
if (!T->isDependentType() && !RD->isDependentContext() &&
!declaresSameEntity(T->getAsCXXRecordDecl(), RD))
return false;
for (const auto *ExistingPNA : D->specific_attrs<PreferredNameAttr>())
if (S.Context.hasSameType(ExistingPNA->getTypedefType(),
PNA->getTypedefType()))
return false;
return true;
}
if (const auto *BA = dyn_cast<BuiltinAttr>(A)) {
const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
switch (BA->getID()) {
case Builtin::BIforward:
// Do not treat 'std::forward' as a builtin if it takes an rvalue reference
// type and returns an lvalue reference type. The library implementation
// will produce an error in this case; don't get in its way.
if (FD && FD->getNumParams() >= 1 &&
FD->getParamDecl(0)->getType()->isRValueReferenceType() &&
FD->getReturnType()->isLValueReferenceType()) {
return false;
}
[[fallthrough]];
case Builtin::BImove:
case Builtin::BImove_if_noexcept:
// HACK: Super-old versions of libc++ (3.1 and earlier) provide
// std::forward and std::move overloads that sometimes return by value
// instead of by reference when building in C++98 mode. Don't treat such
// cases as builtins.
if (FD && !FD->getReturnType()->isReferenceType())
return false;
break;
}
}
return true;
}
static void instantiateDependentHLSLParamModifierAttr(
Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
const HLSLParamModifierAttr *Attr, Decl *New) {
ParmVarDecl *P = cast<ParmVarDecl>(New);
P->addAttr(Attr->clone(S.getASTContext()));
P->setType(S.getASTContext().getLValueReferenceType(P->getType()));
}
void Sema::InstantiateAttrsForDecl(
const MultiLevelTemplateArgumentList &TemplateArgs, const Decl *Tmpl,
Decl *New, LateInstantiatedAttrVec *LateAttrs,
LocalInstantiationScope *OuterMostScope) {
if (NamedDecl *ND = dyn_cast<NamedDecl>(New)) {
// FIXME: This function is called multiple times for the same template
// specialization. We should only instantiate attributes that were added
// since the previous instantiation.
for (const auto *TmplAttr : Tmpl->attrs()) {
if (!isRelevantAttr(*this, New, TmplAttr))
continue;
// FIXME: If any of the special case versions from InstantiateAttrs become
// applicable to template declaration, we'll need to add them here.
CXXThisScopeRAII ThisScope(
*this, dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext()),
Qualifiers(), ND->isCXXInstanceMember());
Attr *NewAttr = sema::instantiateTemplateAttributeForDecl(
TmplAttr, Context, *this, TemplateArgs);
if (NewAttr && isRelevantAttr(*this, New, NewAttr))
New->addAttr(NewAttr);
}
}
}
static Sema::RetainOwnershipKind
attrToRetainOwnershipKind(const Attr *A) {
switch (A->getKind()) {
case clang::attr::CFConsumed:
return Sema::RetainOwnershipKind::CF;
case clang::attr::OSConsumed:
return Sema::RetainOwnershipKind::OS;
case clang::attr::NSConsumed:
return Sema::RetainOwnershipKind::NS;
default:
llvm_unreachable("Wrong argument supplied");
}
}
void Sema::InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
const Decl *Tmpl, Decl *New,
LateInstantiatedAttrVec *LateAttrs,
LocalInstantiationScope *OuterMostScope) {
for (const auto *TmplAttr : Tmpl->attrs()) {
if (!isRelevantAttr(*this, New, TmplAttr))
continue;
// FIXME: This should be generalized to more than just the AlignedAttr.
const AlignedAttr *Aligned = dyn_cast<AlignedAttr>(TmplAttr);
if (Aligned && Aligned->isAlignmentDependent()) {
instantiateDependentAlignedAttr(*this, TemplateArgs, Aligned, New);
continue;
}
if (const auto *AssumeAligned = dyn_cast<AssumeAlignedAttr>(TmplAttr)) {
instantiateDependentAssumeAlignedAttr(*this, TemplateArgs, AssumeAligned, New);
continue;
}
if (const auto *AlignValue = dyn_cast<AlignValueAttr>(TmplAttr)) {
instantiateDependentAlignValueAttr(*this, TemplateArgs, AlignValue, New);
continue;
}
if (const auto *AllocAlign = dyn_cast<AllocAlignAttr>(TmplAttr)) {
instantiateDependentAllocAlignAttr(*this, TemplateArgs, AllocAlign, New);
continue;
}
if (const auto *Annotate = dyn_cast<AnnotateAttr>(TmplAttr)) {
instantiateDependentAnnotationAttr(*this, TemplateArgs, Annotate, New);
continue;
}
if (const auto *EnableIf = dyn_cast<EnableIfAttr>(TmplAttr)) {
instantiateDependentEnableIfAttr(*this, TemplateArgs, EnableIf, Tmpl,
cast<FunctionDecl>(New));
continue;
}
if (const auto *DiagnoseIf = dyn_cast<DiagnoseIfAttr>(TmplAttr)) {
instantiateDependentDiagnoseIfAttr(*this, TemplateArgs, DiagnoseIf, Tmpl,
cast<FunctionDecl>(New));
continue;
}
if (const auto *CUDALaunchBounds =
dyn_cast<CUDALaunchBoundsAttr>(TmplAttr)) {
instantiateDependentCUDALaunchBoundsAttr(*this, TemplateArgs,
*CUDALaunchBounds, New);
continue;
}
if (const auto *Mode = dyn_cast<ModeAttr>(TmplAttr)) {
instantiateDependentModeAttr(*this, TemplateArgs, *Mode, New);
continue;
}
if (const auto *OMPAttr = dyn_cast<OMPDeclareSimdDeclAttr>(TmplAttr)) {
instantiateOMPDeclareSimdDeclAttr(*this, TemplateArgs, *OMPAttr, New);
continue;
}
if (const auto *OMPAttr = dyn_cast<OMPDeclareVariantAttr>(TmplAttr)) {
instantiateOMPDeclareVariantAttr(*this, TemplateArgs, *OMPAttr, New);
continue;
}
if (const auto *AMDGPUFlatWorkGroupSize =
dyn_cast<AMDGPUFlatWorkGroupSizeAttr>(TmplAttr)) {
instantiateDependentAMDGPUFlatWorkGroupSizeAttr(
*this, TemplateArgs, *AMDGPUFlatWorkGroupSize, New);
}
if (const auto *AMDGPUFlatWorkGroupSize =
dyn_cast<AMDGPUWavesPerEUAttr>(TmplAttr)) {
instantiateDependentAMDGPUWavesPerEUAttr(*this, TemplateArgs,
*AMDGPUFlatWorkGroupSize, New);
}
if (const auto *AMDGPUMaxNumWorkGroups =
dyn_cast<AMDGPUMaxNumWorkGroupsAttr>(TmplAttr)) {
instantiateDependentAMDGPUMaxNumWorkGroupsAttr(
*this, TemplateArgs, *AMDGPUMaxNumWorkGroups, New);
}
if (const auto *ParamAttr = dyn_cast<HLSLParamModifierAttr>(TmplAttr)) {
instantiateDependentHLSLParamModifierAttr(*this, TemplateArgs, ParamAttr,
New);
continue;
}
// Existing DLL attribute on the instantiation takes precedence.
if (TmplAttr->getKind() == attr::DLLExport ||
TmplAttr->getKind() == attr::DLLImport) {
if (New->hasAttr<DLLExportAttr>() || New->hasAttr<DLLImportAttr>()) {
continue;
}
}
if (const auto *ABIAttr = dyn_cast<ParameterABIAttr>(TmplAttr)) {
AddParameterABIAttr(New, *ABIAttr, ABIAttr->getABI());
continue;
}
if (isa<NSConsumedAttr>(TmplAttr) || isa<OSConsumedAttr>(TmplAttr) ||
isa<CFConsumedAttr>(TmplAttr)) {
AddXConsumedAttr(New, *TmplAttr, attrToRetainOwnershipKind(TmplAttr),
/*template instantiation=*/true);
continue;
}
if (auto *A = dyn_cast<PointerAttr>(TmplAttr)) {
if (!New->hasAttr<PointerAttr>())
New->addAttr(A->clone(Context));
continue;
}
if (auto *A = dyn_cast<OwnerAttr>(TmplAttr)) {
if (!New->hasAttr<OwnerAttr>())
New->addAttr(A->clone(Context));
continue;
}
if (auto *A = dyn_cast<SYCLKernelAttr>(TmplAttr)) {
instantiateDependentSYCLKernelAttr(*this, TemplateArgs, *A, New);
continue;
}
assert(!TmplAttr->isPackExpansion());
if (TmplAttr->isLateParsed() && LateAttrs) {
// Late parsed attributes must be instantiated and attached after the
// enclosing class has been instantiated. See Sema::InstantiateClass.
LocalInstantiationScope *Saved = nullptr;
if (CurrentInstantiationScope)
Saved = CurrentInstantiationScope->cloneScopes(OuterMostScope);
LateAttrs->push_back(LateInstantiatedAttribute(TmplAttr, Saved, New));
} else {
// Allow 'this' within late-parsed attributes.
auto *ND = cast<NamedDecl>(New);
auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
CXXThisScopeRAII ThisScope(*this, ThisContext, Qualifiers(),
ND->isCXXInstanceMember());
Attr *NewAttr = sema::instantiateTemplateAttribute(TmplAttr, Context,
*this, TemplateArgs);
if (NewAttr && isRelevantAttr(*this, New, TmplAttr))
New->addAttr(NewAttr);
}
}
}
/// Update instantiation attributes after template was late parsed.
///
/// Some attributes are evaluated based on the body of template. If it is
/// late parsed, such attributes cannot be evaluated when declaration is
/// instantiated. This function is used to update instantiation attributes when
/// template definition is ready.
void Sema::updateAttrsForLateParsedTemplate(const Decl *Pattern, Decl *Inst) {
for (const auto *Attr : Pattern->attrs()) {
if (auto *A = dyn_cast<StrictFPAttr>(Attr)) {
if (!Inst->hasAttr<StrictFPAttr>())
Inst->addAttr(A->clone(getASTContext()));
continue;
}
}
}
/// In the MS ABI, we need to instantiate default arguments of dllexported
/// default constructors along with the constructor definition. This allows IR
/// gen to emit a constructor closure which calls the default constructor with
/// its default arguments.
void Sema::InstantiateDefaultCtorDefaultArgs(CXXConstructorDecl *Ctor) {
assert(Context.getTargetInfo().getCXXABI().isMicrosoft() &&
Ctor->isDefaultConstructor());
unsigned NumParams = Ctor->getNumParams();
if (NumParams == 0)
return;
DLLExportAttr *Attr = Ctor->getAttr<DLLExportAttr>();
if (!Attr)
return;
for (unsigned I = 0; I != NumParams; ++I) {
(void)CheckCXXDefaultArgExpr(Attr->getLocation(), Ctor,
Ctor->getParamDecl(I));
CleanupVarDeclMarking();
}
}
/// Get the previous declaration of a declaration for the purposes of template
/// instantiation. If this finds a previous declaration, then the previous
/// declaration of the instantiation of D should be an instantiation of the
/// result of this function.
template<typename DeclT>
static DeclT *getPreviousDeclForInstantiation(DeclT *D) {
DeclT *Result = D->getPreviousDecl();
// If the declaration is within a class, and the previous declaration was
// merged from a different definition of that class, then we don't have a
// previous declaration for the purpose of template instantiation.
if (Result && isa<CXXRecordDecl>(D->getDeclContext()) &&
D->getLexicalDeclContext() != Result->getLexicalDeclContext())
return nullptr;
return Result;
}
Decl *
TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
llvm_unreachable("Translation units cannot be instantiated");
}
Decl *TemplateDeclInstantiator::VisitHLSLBufferDecl(HLSLBufferDecl *Decl) {
llvm_unreachable("HLSL buffer declarations cannot be instantiated");
}
Decl *
TemplateDeclInstantiator::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
llvm_unreachable("pragma comment cannot be instantiated");
}
Decl *TemplateDeclInstantiator::VisitPragmaDetectMismatchDecl(
PragmaDetectMismatchDecl *D) {
llvm_unreachable("pragma comment cannot be instantiated");
}
Decl *
TemplateDeclInstantiator::VisitExternCContextDecl(ExternCContextDecl *D) {
llvm_unreachable("extern \"C\" context cannot be instantiated");
}
Decl *TemplateDeclInstantiator::VisitMSGuidDecl(MSGuidDecl *D) {
llvm_unreachable("GUID declaration cannot be instantiated");
}
Decl *TemplateDeclInstantiator::VisitUnnamedGlobalConstantDecl(
UnnamedGlobalConstantDecl *D) {
llvm_unreachable("UnnamedGlobalConstantDecl cannot be instantiated");
}
Decl *TemplateDeclInstantiator::VisitTemplateParamObjectDecl(
TemplateParamObjectDecl *D) {
llvm_unreachable("template parameter objects cannot be instantiated");
}
Decl *
TemplateDeclInstantiator::VisitLabelDecl(LabelDecl *D) {
LabelDecl *Inst = LabelDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getIdentifier());
Owner->addDecl(Inst);
return Inst;
}
Decl *
TemplateDeclInstantiator::VisitNamespaceDecl(NamespaceDecl *D) {
llvm_unreachable("Namespaces cannot be instantiated");
}
Decl *
TemplateDeclInstantiator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
NamespaceAliasDecl *Inst
= NamespaceAliasDecl::Create(SemaRef.Context, Owner,
D->getNamespaceLoc(),
D->getAliasLoc(),
D->getIdentifier(),
D->getQualifierLoc(),
D->getTargetNameLoc(),
D->getNamespace());
Owner->addDecl(Inst);
return Inst;
}
Decl *TemplateDeclInstantiator::InstantiateTypedefNameDecl(TypedefNameDecl *D,
bool IsTypeAlias) {
bool Invalid = false;
TypeSourceInfo *DI = D->getTypeSourceInfo();
if (DI->getType()->isInstantiationDependentType() ||
DI->getType()->isVariablyModifiedType()) {
DI = SemaRef.SubstType(DI, TemplateArgs,
D->getLocation(), D->getDeclName());
if (!DI) {
Invalid = true;
DI = SemaRef.Context.getTrivialTypeSourceInfo(SemaRef.Context.IntTy);
}
} else {
SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
}
// HACK: 2012-10-23 g++ has a bug where it gets the value kind of ?: wrong.
// libstdc++ relies upon this bug in its implementation of common_type. If we
// happen to be processing that implementation, fake up the g++ ?:
// semantics. See LWG issue 2141 for more information on the bug. The bugs
// are fixed in g++ and libstdc++ 4.9.0 (2014-04-22).
const DecltypeType *DT = DI->getType()->getAs<DecltypeType>();
CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext());
if (DT && RD && isa<ConditionalOperator>(DT->getUnderlyingExpr()) &&
DT->isReferenceType() &&
RD->getEnclosingNamespaceContext() == SemaRef.getStdNamespace() &&
RD->getIdentifier() && RD->getIdentifier()->isStr("common_type") &&
D->getIdentifier() && D->getIdentifier()->isStr("type") &&
SemaRef.getSourceManager().isInSystemHeader(D->getBeginLoc()))
// Fold it to the (non-reference) type which g++ would have produced.
DI = SemaRef.Context.getTrivialTypeSourceInfo(
DI->getType().getNonReferenceType());
// Create the new typedef
TypedefNameDecl *Typedef;
if (IsTypeAlias)
Typedef = TypeAliasDecl::Create(SemaRef.Context, Owner, D->getBeginLoc(),
D->getLocation(), D->getIdentifier(), DI);
else
Typedef = TypedefDecl::Create(SemaRef.Context, Owner, D->getBeginLoc(),
D->getLocation(), D->getIdentifier(), DI);
if (Invalid)
Typedef->setInvalidDecl();
// If the old typedef was the name for linkage purposes of an anonymous
// tag decl, re-establish that relationship for the new typedef.
if (const TagType *oldTagType = D->getUnderlyingType()->getAs<TagType>()) {
TagDecl *oldTag = oldTagType->getDecl();
if (oldTag->getTypedefNameForAnonDecl() == D && !Invalid) {
TagDecl *newTag = DI->getType()->castAs<TagType>()->getDecl();
assert(!newTag->hasNameForLinkage());
newTag->setTypedefNameForAnonDecl(Typedef);
}
}
if (TypedefNameDecl *Prev = getPreviousDeclForInstantiation(D)) {
NamedDecl *InstPrev = SemaRef.FindInstantiatedDecl(D->getLocation(), Prev,
TemplateArgs);
if (!InstPrev)
return nullptr;
TypedefNameDecl *InstPrevTypedef = cast<TypedefNameDecl>(InstPrev);
// If the typedef types are not identical, reject them.
SemaRef.isIncompatibleTypedef(InstPrevTypedef, Typedef);
Typedef->setPreviousDecl(InstPrevTypedef);
}
SemaRef.InstantiateAttrs(TemplateArgs, D, Typedef);
if (D->getUnderlyingType()->getAs<DependentNameType>())
SemaRef.inferGslPointerAttribute(Typedef);
Typedef->setAccess(D->getAccess());
Typedef->setReferenced(D->isReferenced());
return Typedef;
}
Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/false);
if (Typedef)
Owner->addDecl(Typedef);
return Typedef;
}
Decl *TemplateDeclInstantiator::VisitTypeAliasDecl(TypeAliasDecl *D) {
Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/true);
if (Typedef)
Owner->addDecl(Typedef);
return Typedef;
}
Decl *
TemplateDeclInstantiator::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
// Create a local instantiation scope for this type alias template, which
// will contain the instantiations of the template parameters.
LocalInstantiationScope Scope(SemaRef);
TemplateParameterList *TempParams = D->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
TypeAliasDecl *Pattern = D->getTemplatedDecl();
Sema::InstantiatingTemplate InstTemplate(
SemaRef, D->getBeginLoc(), D,
D->getTemplateDepth() >= TemplateArgs.getNumLevels()
? ArrayRef<TemplateArgument>()
: (TemplateArgs.begin() + TemplateArgs.getNumLevels() - 1 -
D->getTemplateDepth())
->Args);
if (InstTemplate.isInvalid())
return nullptr;
TypeAliasTemplateDecl *PrevAliasTemplate = nullptr;
if (getPreviousDeclForInstantiation<TypedefNameDecl>(Pattern)) {
DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
if (!Found.empty()) {
PrevAliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Found.front());
}
}
TypeAliasDecl *AliasInst = cast_or_null<TypeAliasDecl>(
InstantiateTypedefNameDecl(Pattern, /*IsTypeAlias=*/true));
if (!AliasInst)
return nullptr;
TypeAliasTemplateDecl *Inst
= TypeAliasTemplateDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getDeclName(), InstParams, AliasInst);
AliasInst->setDescribedAliasTemplate(Inst);
if (PrevAliasTemplate)
Inst->setPreviousDecl(PrevAliasTemplate);
Inst->setAccess(D->getAccess());
if (!PrevAliasTemplate)
Inst->setInstantiatedFromMemberTemplate(D);
Owner->addDecl(Inst);
return Inst;
}
Decl *TemplateDeclInstantiator::VisitBindingDecl(BindingDecl *D) {
auto *NewBD = BindingDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getIdentifier());
NewBD->setReferenced(D->isReferenced());
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewBD);
return NewBD;
}
Decl *TemplateDeclInstantiator::VisitDecompositionDecl(DecompositionDecl *D) {
// Transform the bindings first.
SmallVector<BindingDecl*, 16> NewBindings;
for (auto *OldBD : D->bindings())
NewBindings.push_back(cast<BindingDecl>(VisitBindingDecl(OldBD)));
ArrayRef<BindingDecl*> NewBindingArray = NewBindings;
auto *NewDD = cast_or_null<DecompositionDecl>(
VisitVarDecl(D, /*InstantiatingVarTemplate=*/false, &NewBindingArray));
if (!NewDD || NewDD->isInvalidDecl())
for (auto *NewBD : NewBindings)
NewBD->setInvalidDecl();
return NewDD;
}
Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
return VisitVarDecl(D, /*InstantiatingVarTemplate=*/false);
}
Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D,
bool InstantiatingVarTemplate,
ArrayRef<BindingDecl*> *Bindings) {
// Do substitution on the type of the declaration
TypeSourceInfo *DI = SemaRef.SubstType(
D->getTypeSourceInfo(), TemplateArgs, D->getTypeSpecStartLoc(),
D->getDeclName(), /*AllowDeducedTST*/true);
if (!DI)
return nullptr;
if (DI->getType()->isFunctionType()) {
SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
<< D->isStaticDataMember() << DI->getType();
return nullptr;
}
DeclContext *DC = Owner;
if (D->isLocalExternDecl())
SemaRef.adjustContextForLocalExternDecl(DC);
// Build the instantiated declaration.
VarDecl *Var;
if (Bindings)
Var = DecompositionDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
D->getLocation(), DI->getType(), DI,
D->getStorageClass(), *Bindings);
else
Var = VarDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
D->getLocation(), D->getIdentifier(), DI->getType(),
DI, D->getStorageClass());
// In ARC, infer 'retaining' for variables of retainable type.
if (SemaRef.getLangOpts().ObjCAutoRefCount &&
SemaRef.inferObjCARCLifetime(Var))
Var->setInvalidDecl();
if (SemaRef.getLangOpts().OpenCL)
SemaRef.deduceOpenCLAddressSpace(Var);
// Substitute the nested name specifier, if any.
if (SubstQualifier(D, Var))
return nullptr;
SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
StartingScope, InstantiatingVarTemplate);
if (D->isNRVOVariable() && !Var->isInvalidDecl()) {
QualType RT;
if (auto *F = dyn_cast<FunctionDecl>(DC))
RT = F->getReturnType();
else if (isa<BlockDecl>(DC))
RT = cast<FunctionType>(SemaRef.getCurBlock()->FunctionType)
->getReturnType();
else
llvm_unreachable("Unknown context type");
// This is the last chance we have of checking copy elision eligibility
// for functions in dependent contexts. The sema actions for building
// the return statement during template instantiation will have no effect
// regarding copy elision, since NRVO propagation runs on the scope exit
// actions, and these are not run on instantiation.
// This might run through some VarDecls which were returned from non-taken
// 'if constexpr' branches, and these will end up being constructed on the
// return slot even if they will never be returned, as a sort of accidental
// 'optimization'. Notably, functions with 'auto' return types won't have it
// deduced by this point. Coupled with the limitation described
// previously, this makes it very hard to support copy elision for these.
Sema::NamedReturnInfo Info = SemaRef.getNamedReturnInfo(Var);
bool NRVO = SemaRef.getCopyElisionCandidate(Info, RT) != nullptr;
Var->setNRVOVariable(NRVO);
}
Var->setImplicit(D->isImplicit());
if (Var->isStaticLocal())
SemaRef.CheckStaticLocalForDllExport(Var);
if (Var->getTLSKind())
SemaRef.CheckThreadLocalForLargeAlignment(Var);
return Var;
}
Decl *TemplateDeclInstantiator::VisitAccessSpecDecl(AccessSpecDecl *D) {
AccessSpecDecl* AD
= AccessSpecDecl::Create(SemaRef.Context, D->getAccess(), Owner,
D->getAccessSpecifierLoc(), D->getColonLoc());
Owner->addHiddenDecl(AD);
return AD;
}
Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
bool Invalid = false;
TypeSourceInfo *DI = D->getTypeSourceInfo();
if (DI->getType()->isInstantiationDependentType() ||
DI->getType()->isVariablyModifiedType()) {
DI = SemaRef.SubstType(DI, TemplateArgs,
D->getLocation(), D->getDeclName());
if (!DI) {
DI = D->getTypeSourceInfo();
Invalid = true;
} else if (DI->getType()->isFunctionType()) {
// C++ [temp.arg.type]p3:
// If a declaration acquires a function type through a type
// dependent on a template-parameter and this causes a
// declaration that does not use the syntactic form of a
// function declarator to have function type, the program is
// ill-formed.
SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
<< DI->getType();
Invalid = true;
}
} else {
SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
}
Expr *BitWidth = D->getBitWidth();
if (Invalid)
BitWidth = nullptr;
else if (BitWidth) {
// The bit-width expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult InstantiatedBitWidth
= SemaRef.SubstExpr(BitWidth, TemplateArgs);
if (InstantiatedBitWidth.isInvalid()) {
Invalid = true;
BitWidth = nullptr;
} else
BitWidth = InstantiatedBitWidth.getAs<Expr>();
}
FieldDecl *Field = SemaRef.CheckFieldDecl(D->getDeclName(),
DI->getType(), DI,
cast<RecordDecl>(Owner),
D->getLocation(),
D->isMutable(),
BitWidth,
D->getInClassInitStyle(),
D->getInnerLocStart(),
D->getAccess(),
nullptr);
if (!Field) {
cast<Decl>(Owner)->setInvalidDecl();
return nullptr;
}
SemaRef.InstantiateAttrs(TemplateArgs, D, Field, LateAttrs, StartingScope);
if (Field->hasAttrs())
SemaRef.CheckAlignasUnderalignment(Field);
if (Invalid)
Field->setInvalidDecl();
if (!Field->getDeclName()) {
// Keep track of where this decl came from.
SemaRef.Context.setInstantiatedFromUnnamedFieldDecl(Field, D);
}
if (CXXRecordDecl *Parent= dyn_cast<CXXRecordDecl>(Field->getDeclContext())) {
if (Parent->isAnonymousStructOrUnion() &&
Parent->getRedeclContext()->isFunctionOrMethod())
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Field);
}
Field->setImplicit(D->isImplicit());
Field->setAccess(D->getAccess());
Owner->addDecl(Field);
return Field;
}
Decl *TemplateDeclInstantiator::VisitMSPropertyDecl(MSPropertyDecl *D) {
bool Invalid = false;
TypeSourceInfo *DI = D->getTypeSourceInfo();
if (DI->getType()->isVariablyModifiedType()) {
SemaRef.Diag(D->getLocation(), diag::err_property_is_variably_modified)
<< D;
Invalid = true;
} else if (DI->getType()->isInstantiationDependentType()) {
DI = SemaRef.SubstType(DI, TemplateArgs,
D->getLocation(), D->getDeclName());
if (!DI) {
DI = D->getTypeSourceInfo();
Invalid = true;
} else if (DI->getType()->isFunctionType()) {
// C++ [temp.arg.type]p3:
// If a declaration acquires a function type through a type
// dependent on a template-parameter and this causes a
// declaration that does not use the syntactic form of a
// function declarator to have function type, the program is
// ill-formed.
SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
<< DI->getType();
Invalid = true;
}
} else {
SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
}
MSPropertyDecl *Property = MSPropertyDecl::Create(
SemaRef.Context, Owner, D->getLocation(), D->getDeclName(), DI->getType(),
DI, D->getBeginLoc(), D->getGetterId(), D->getSetterId());
SemaRef.InstantiateAttrs(TemplateArgs, D, Property, LateAttrs,
StartingScope);
if (Invalid)
Property->setInvalidDecl();
Property->setAccess(D->getAccess());
Owner->addDecl(Property);
return Property;
}
Decl *TemplateDeclInstantiator::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
NamedDecl **NamedChain =
new (SemaRef.Context)NamedDecl*[D->getChainingSize()];
int i = 0;
for (auto *PI : D->chain()) {
NamedDecl *Next = SemaRef.FindInstantiatedDecl(D->getLocation(), PI,
TemplateArgs);
if (!Next)
return nullptr;
NamedChain[i++] = Next;
}
QualType T = cast<FieldDecl>(NamedChain[i-1])->getType();
IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
SemaRef.Context, Owner, D->getLocation(), D->getIdentifier(), T,
{NamedChain, D->getChainingSize()});
for (const auto *Attr : D->attrs())
IndirectField->addAttr(Attr->clone(SemaRef.Context));
IndirectField->setImplicit(D->isImplicit());
IndirectField->setAccess(D->getAccess());
Owner->addDecl(IndirectField);
return IndirectField;
}
Decl *TemplateDeclInstantiator::VisitFriendDecl(FriendDecl *D) {
// Handle friend type expressions by simply substituting template
// parameters into the pattern type and checking the result.
if (TypeSourceInfo *Ty = D->getFriendType()) {
TypeSourceInfo *InstTy;
// If this is an unsupported friend, don't bother substituting template
// arguments into it. The actual type referred to won't be used by any
// parts of Clang, and may not be valid for instantiating. Just use the
// same info for the instantiated friend.
if (D->isUnsupportedFriend()) {
InstTy = Ty;
} else {
InstTy = SemaRef.SubstType(Ty, TemplateArgs,
D->getLocation(), DeclarationName());
}
if (!InstTy)
return nullptr;
FriendDecl *FD = FriendDecl::Create(
SemaRef.Context, Owner, D->getLocation(), InstTy, D->getFriendLoc());
FD->setAccess(AS_public);
FD->setUnsupportedFriend(D->isUnsupportedFriend());
Owner->addDecl(FD);
return FD;
}
NamedDecl *ND = D->getFriendDecl();
assert(ND && "friend decl must be a decl or a type!");
// All of the Visit implementations for the various potential friend
// declarations have to be carefully written to work for friend
// objects, with the most important detail being that the target
// decl should almost certainly not be placed in Owner.
Decl *NewND = Visit(ND);
if (!NewND) return nullptr;
FriendDecl *FD =
FriendDecl::Create(SemaRef.Context, Owner, D->getLocation(),
cast<NamedDecl>(NewND), D->getFriendLoc());
FD->setAccess(AS_public);
FD->setUnsupportedFriend(D->isUnsupportedFriend());
Owner->addDecl(FD);
return FD;
}
Decl *TemplateDeclInstantiator::VisitStaticAssertDecl(StaticAssertDecl *D) {
Expr *AssertExpr = D->getAssertExpr();
// The expression in a static assertion is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult InstantiatedAssertExpr
= SemaRef.SubstExpr(AssertExpr, TemplateArgs);
if (InstantiatedAssertExpr.isInvalid())
return nullptr;
ExprResult InstantiatedMessageExpr =
SemaRef.SubstExpr(D->getMessage(), TemplateArgs);
if (InstantiatedMessageExpr.isInvalid())
return nullptr;
return SemaRef.BuildStaticAssertDeclaration(
D->getLocation(), InstantiatedAssertExpr.get(),
InstantiatedMessageExpr.get(), D->getRParenLoc(), D->isFailed());
}
Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
EnumDecl *PrevDecl = nullptr;
if (EnumDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
PatternPrev,
TemplateArgs);
if (!Prev) return nullptr;
PrevDecl = cast<EnumDecl>(Prev);
}
EnumDecl *Enum =
EnumDecl::Create(SemaRef.Context, Owner, D->getBeginLoc(),
D->getLocation(), D->getIdentifier(), PrevDecl,
D->isScoped(), D->isScopedUsingClassTag(), D->isFixed());
if (D->isFixed()) {
if (TypeSourceInfo *TI = D->getIntegerTypeSourceInfo()) {
// If we have type source information for the underlying type, it means it
// has been explicitly set by the user. Perform substitution on it before
// moving on.
SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
TypeSourceInfo *NewTI = SemaRef.SubstType(TI, TemplateArgs, UnderlyingLoc,
DeclarationName());
if (!NewTI || SemaRef.CheckEnumUnderlyingType(NewTI))
Enum->setIntegerType(SemaRef.Context.IntTy);
else
Enum->setIntegerTypeSourceInfo(NewTI);
} else {
assert(!D->getIntegerType()->isDependentType()
&& "Dependent type without type source info");
Enum->setIntegerType(D->getIntegerType());
}
}
SemaRef.InstantiateAttrs(TemplateArgs, D, Enum);
Enum->setInstantiationOfMemberEnum(D, TSK_ImplicitInstantiation);
Enum->setAccess(D->getAccess());
// Forward the mangling number from the template to the instantiated decl.
SemaRef.Context.setManglingNumber(Enum, SemaRef.Context.getManglingNumber(D));
// See if the old tag was defined along with a declarator.
// If it did, mark the new tag as being associated with that declarator.
if (DeclaratorDecl *DD = SemaRef.Context.getDeclaratorForUnnamedTagDecl(D))
SemaRef.Context.addDeclaratorForUnnamedTagDecl(Enum, DD);
// See if the old tag was defined along with a typedef.
// If it did, mark the new tag as being associated with that typedef.
if (TypedefNameDecl *TND = SemaRef.Context.getTypedefNameForUnnamedTagDecl(D))
SemaRef.Context.addTypedefNameForUnnamedTagDecl(Enum, TND);
if (SubstQualifier(D, Enum)) return nullptr;
Owner->addDecl(Enum);
EnumDecl *Def = D->getDefinition();
if (Def && Def != D) {
// If this is an out-of-line definition of an enum member template, check
// that the underlying types match in the instantiation of both
// declarations.
if (TypeSourceInfo *TI = Def->getIntegerTypeSourceInfo()) {
SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
QualType DefnUnderlying =
SemaRef.SubstType(TI->getType(), TemplateArgs,
UnderlyingLoc, DeclarationName());
SemaRef.CheckEnumRedeclaration(Def->getLocation(), Def->isScoped(),
DefnUnderlying, /*IsFixed=*/true, Enum);
}
}
// C++11 [temp.inst]p1: The implicit instantiation of a class template
// specialization causes the implicit instantiation of the declarations, but
// not the definitions of scoped member enumerations.
//
// DR1484 clarifies that enumeration definitions inside of a template
// declaration aren't considered entities that can be separately instantiated
// from the rest of the entity they are declared inside of.
if (isDeclWithinFunction(D) ? D == Def : Def && !Enum->isScoped()) {
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Enum);
InstantiateEnumDefinition(Enum, Def);
}
return Enum;
}
void TemplateDeclInstantiator::InstantiateEnumDefinition(
EnumDecl *Enum, EnumDecl *Pattern) {
Enum->startDefinition();
// Update the location to refer to the definition.
Enum->setLocation(Pattern->getLocation());
SmallVector<Decl*, 4> Enumerators;
EnumConstantDecl *LastEnumConst = nullptr;
for (auto *EC : Pattern->enumerators()) {
// The specified value for the enumerator.
ExprResult Value((Expr *)nullptr);
if (Expr *UninstValue = EC->getInitExpr()) {
// The enumerator's value expression is a constant expression.
EnterExpressionEvaluationContext Unevaluated(
SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
Value = SemaRef.SubstExpr(UninstValue, TemplateArgs);
}
// Drop the initial value and continue.
bool isInvalid = false;
if (Value.isInvalid()) {
Value = nullptr;
isInvalid = true;
}
EnumConstantDecl *EnumConst
= SemaRef.CheckEnumConstant(Enum, LastEnumConst,
EC->getLocation(), EC->getIdentifier(),
Value.get());
if (isInvalid) {
if (EnumConst)
EnumConst->setInvalidDecl();
Enum->setInvalidDecl();
}
if (EnumConst) {
SemaRef.InstantiateAttrs(TemplateArgs, EC, EnumConst);
EnumConst->setAccess(Enum->getAccess());
Enum->addDecl(EnumConst);
Enumerators.push_back(EnumConst);
LastEnumConst = EnumConst;
if (Pattern->getDeclContext()->isFunctionOrMethod() &&
!Enum->isScoped()) {
// If the enumeration is within a function or method, record the enum
// constant as a local.
SemaRef.CurrentInstantiationScope->InstantiatedLocal(EC, EnumConst);
}
}
}
SemaRef.ActOnEnumBody(Enum->getLocation(), Enum->getBraceRange(), Enum,
Enumerators, nullptr, ParsedAttributesView());
}
Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
llvm_unreachable("EnumConstantDecls can only occur within EnumDecls.");
}
Decl *
TemplateDeclInstantiator::VisitBuiltinTemplateDecl(BuiltinTemplateDecl *D) {
llvm_unreachable("BuiltinTemplateDecls cannot be instantiated.");
}
Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
bool isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
// Create a local instantiation scope for this class template, which
// will contain the instantiations of the template parameters.
LocalInstantiationScope Scope(SemaRef);
TemplateParameterList *TempParams = D->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
CXXRecordDecl *Pattern = D->getTemplatedDecl();
// Instantiate the qualifier. We have to do this first in case
// we're a friend declaration, because if we are then we need to put
// the new declaration in the appropriate context.
NestedNameSpecifierLoc QualifierLoc = Pattern->getQualifierLoc();
if (QualifierLoc) {
QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
TemplateArgs);
if (!QualifierLoc)
return nullptr;
}
CXXRecordDecl *PrevDecl = nullptr;
ClassTemplateDecl *PrevClassTemplate = nullptr;
if (!isFriend && getPreviousDeclForInstantiation(Pattern)) {
DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
if (!Found.empty()) {
PrevClassTemplate = dyn_cast<ClassTemplateDecl>(Found.front());
if (PrevClassTemplate)
PrevDecl = PrevClassTemplate->getTemplatedDecl();
}
}
// If this isn't a friend, then it's a member template, in which
// case we just want to build the instantiation in the
// specialization. If it is a friend, we want to build it in
// the appropriate context.
DeclContext *DC = Owner;
if (isFriend) {
if (QualifierLoc) {
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
DC = SemaRef.computeDeclContext(SS);
if (!DC) return nullptr;
} else {
DC = SemaRef.FindInstantiatedContext(Pattern->getLocation(),
Pattern->getDeclContext(),
TemplateArgs);
}
// Look for a previous declaration of the template in the owning
// context.
LookupResult R(SemaRef, Pattern->getDeclName(), Pattern->getLocation(),
Sema::LookupOrdinaryName,
SemaRef.forRedeclarationInCurContext());
SemaRef.LookupQualifiedName(R, DC);
if (R.isSingleResult()) {
PrevClassTemplate = R.getAsSingle<ClassTemplateDecl>();
if (PrevClassTemplate)
PrevDecl = PrevClassTemplate->getTemplatedDecl();
}
if (!PrevClassTemplate && QualifierLoc) {
SemaRef.Diag(Pattern->getLocation(), diag::err_not_tag_in_scope)
<< llvm::to_underlying(D->getTemplatedDecl()->getTagKind())
<< Pattern->getDeclName() << DC << QualifierLoc.getSourceRange();
return nullptr;
}
}
CXXRecordDecl *RecordInst = CXXRecordDecl::Create(
SemaRef.Context, Pattern->getTagKind(), DC, Pattern->getBeginLoc(),
Pattern->getLocation(), Pattern->getIdentifier(), PrevDecl,
/*DelayTypeCreation=*/true);
if (QualifierLoc)
RecordInst->setQualifierInfo(QualifierLoc);
SemaRef.InstantiateAttrsForDecl(TemplateArgs, Pattern, RecordInst, LateAttrs,
StartingScope);
ClassTemplateDecl *Inst
= ClassTemplateDecl::Create(SemaRef.Context, DC, D->getLocation(),
D->getIdentifier(), InstParams, RecordInst);
RecordInst->setDescribedClassTemplate(Inst);
if (isFriend) {
assert(!Owner->isDependentContext());
Inst->setLexicalDeclContext(Owner);
RecordInst->setLexicalDeclContext(Owner);
Inst->setObjectOfFriendDecl();
if (PrevClassTemplate) {
Inst->setCommonPtr(PrevClassTemplate->getCommonPtr());
RecordInst->setTypeForDecl(
PrevClassTemplate->getTemplatedDecl()->getTypeForDecl());
const ClassTemplateDecl *MostRecentPrevCT =
PrevClassTemplate->getMostRecentDecl();
TemplateParameterList *PrevParams =
MostRecentPrevCT->getTemplateParameters();
// Make sure the parameter lists match.
if (!SemaRef.TemplateParameterListsAreEqual(
RecordInst, InstParams, MostRecentPrevCT->getTemplatedDecl(),
PrevParams, true, Sema::TPL_TemplateMatch))
return nullptr;
// Do some additional validation, then merge default arguments
// from the existing declarations.
if (SemaRef.CheckTemplateParameterList(InstParams, PrevParams,
Sema::TPC_ClassTemplate))
return nullptr;
Inst->setAccess(PrevClassTemplate->getAccess());
} else {
Inst->setAccess(D->getAccess());
}
Inst->setObjectOfFriendDecl();
// TODO: do we want to track the instantiation progeny of this
// friend target decl?
} else {
Inst->setAccess(D->getAccess());
if (!PrevClassTemplate)
Inst->setInstantiatedFromMemberTemplate(D);
}
Inst->setPreviousDecl(PrevClassTemplate);
// Trigger creation of the type for the instantiation.
SemaRef.Context.getInjectedClassNameType(
RecordInst, Inst->getInjectedClassNameSpecialization());
// Finish handling of friends.
if (isFriend) {
DC->makeDeclVisibleInContext(Inst);
return Inst;
}
if (D->isOutOfLine()) {
Inst->setLexicalDeclContext(D->getLexicalDeclContext());
RecordInst->setLexicalDeclContext(D->getLexicalDeclContext());
}
Owner->addDecl(Inst);
if (!PrevClassTemplate) {
// Queue up any out-of-line partial specializations of this member
// class template; the client will force their instantiation once
// the enclosing class has been instantiated.
SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
D->getPartialSpecializations(PartialSpecs);
for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
OutOfLinePartialSpecs.push_back(std::make_pair(Inst, PartialSpecs[I]));
}
return Inst;
}
Decl *
TemplateDeclInstantiator::VisitClassTemplatePartialSpecializationDecl(
ClassTemplatePartialSpecializationDecl *D) {
ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
// Lookup the already-instantiated declaration in the instantiation
// of the class template and return that.
DeclContext::lookup_result Found
= Owner->lookup(ClassTemplate->getDeclName());
if (Found.empty())
return nullptr;
ClassTemplateDecl *InstClassTemplate
= dyn_cast<ClassTemplateDecl>(Found.front());
if (!InstClassTemplate)
return nullptr;
if (ClassTemplatePartialSpecializationDecl *Result
= InstClassTemplate->findPartialSpecInstantiatedFromMember(D))
return Result;
return InstantiateClassTemplatePartialSpecialization(InstClassTemplate, D);
}
Decl *TemplateDeclInstantiator::VisitVarTemplateDecl(VarTemplateDecl *D) {
assert(D->getTemplatedDecl()->isStaticDataMember() &&
"Only static data member templates are allowed.");
// Create a local instantiation scope for this variable template, which
// will contain the instantiations of the template parameters.
LocalInstantiationScope Scope(SemaRef);
TemplateParameterList *TempParams = D->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
VarDecl *Pattern = D->getTemplatedDecl();
VarTemplateDecl *PrevVarTemplate = nullptr;
if (getPreviousDeclForInstantiation(Pattern)) {
DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
if (!Found.empty())
PrevVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
}
VarDecl *VarInst =
cast_or_null<VarDecl>(VisitVarDecl(Pattern,
/*InstantiatingVarTemplate=*/true));
if (!VarInst) return nullptr;
DeclContext *DC = Owner;
VarTemplateDecl *Inst = VarTemplateDecl::Create(
SemaRef.Context, DC, D->getLocation(), D->getIdentifier(), InstParams,
VarInst);
VarInst->setDescribedVarTemplate(Inst);
Inst->setPreviousDecl(PrevVarTemplate);
Inst->setAccess(D->getAccess());
if (!PrevVarTemplate)
Inst->setInstantiatedFromMemberTemplate(D);
if (D->isOutOfLine()) {
Inst->setLexicalDeclContext(D->getLexicalDeclContext());
VarInst->setLexicalDeclContext(D->getLexicalDeclContext());
}
Owner->addDecl(Inst);
if (!PrevVarTemplate) {
// Queue up any out-of-line partial specializations of this member
// variable template; the client will force their instantiation once
// the enclosing class has been instantiated.
SmallVector<VarTemplatePartialSpecializationDecl *, 4> PartialSpecs;
D->getPartialSpecializations(PartialSpecs);
for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
OutOfLineVarPartialSpecs.push_back(
std::make_pair(Inst, PartialSpecs[I]));
}
return Inst;
}
Decl *TemplateDeclInstantiator::VisitVarTemplatePartialSpecializationDecl(
VarTemplatePartialSpecializationDecl *D) {
assert(D->isStaticDataMember() &&
"Only static data member templates are allowed.");
VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
// Lookup the already-instantiated declaration and return that.
DeclContext::lookup_result Found = Owner->lookup(VarTemplate->getDeclName());
assert(!Found.empty() && "Instantiation found nothing?");
VarTemplateDecl *InstVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
assert(InstVarTemplate && "Instantiation did not find a variable template?");
if (VarTemplatePartialSpecializationDecl *Result =
InstVarTemplate->findPartialSpecInstantiatedFromMember(D))
return Result;
return InstantiateVarTemplatePartialSpecialization(InstVarTemplate, D);
}
Decl *
TemplateDeclInstantiator::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
// Create a local instantiation scope for this function template, which
// will contain the instantiations of the template parameters and then get
// merged with the local instantiation scope for the function template
// itself.
LocalInstantiationScope Scope(SemaRef);
Sema::ConstraintEvalRAII<TemplateDeclInstantiator> RAII(*this);
TemplateParameterList *TempParams = D->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
FunctionDecl *Instantiated = nullptr;
if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(D->getTemplatedDecl()))
Instantiated = cast_or_null<FunctionDecl>(VisitCXXMethodDecl(DMethod,
InstParams));
else
Instantiated = cast_or_null<FunctionDecl>(VisitFunctionDecl(
D->getTemplatedDecl(),
InstParams));
if (!Instantiated)
return nullptr;
// Link the instantiated function template declaration to the function
// template from which it was instantiated.
FunctionTemplateDecl *InstTemplate
= Instantiated->getDescribedFunctionTemplate();
InstTemplate->setAccess(D->getAccess());
assert(InstTemplate &&
"VisitFunctionDecl/CXXMethodDecl didn't create a template!");
bool isFriend = (InstTemplate->getFriendObjectKind() != Decl::FOK_None);
// Link the instantiation back to the pattern *unless* this is a
// non-definition friend declaration.
if (!InstTemplate->getInstantiatedFromMemberTemplate() &&
!(isFriend && !D->getTemplatedDecl()->isThisDeclarationADefinition()))
InstTemplate->setInstantiatedFromMemberTemplate(D);
// Make declarations visible in the appropriate context.
if (!isFriend) {
Owner->addDecl(InstTemplate);
} else if (InstTemplate->getDeclContext()->isRecord() &&
!getPreviousDeclForInstantiation(D)) {
SemaRef.CheckFriendAccess(InstTemplate);
}
return InstTemplate;
}
Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
CXXRecordDecl *PrevDecl = nullptr;
if (CXXRecordDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
PatternPrev,
TemplateArgs);
if (!Prev) return nullptr;
PrevDecl = cast<CXXRecordDecl>(Prev);
}
CXXRecordDecl *Record = nullptr;
bool IsInjectedClassName = D->isInjectedClassName();
if (D->isLambda())
Record = CXXRecordDecl::CreateLambda(
SemaRef.Context, Owner, D->getLambdaTypeInfo(), D->getLocation(),
D->getLambdaDependencyKind(), D->isGenericLambda(),
D->getLambdaCaptureDefault());
else
Record = CXXRecordDecl::Create(SemaRef.Context, D->getTagKind(), Owner,
D->getBeginLoc(), D->getLocation(),
D->getIdentifier(), PrevDecl,
/*DelayTypeCreation=*/IsInjectedClassName);
// Link the type of the injected-class-name to that of the outer class.
if (IsInjectedClassName)
(void)SemaRef.Context.getTypeDeclType(Record, cast<CXXRecordDecl>(Owner));
// Substitute the nested name specifier, if any.
if (SubstQualifier(D, Record))
return nullptr;
SemaRef.InstantiateAttrsForDecl(TemplateArgs, D, Record, LateAttrs,
StartingScope);
Record->setImplicit(D->isImplicit());
// FIXME: Check against AS_none is an ugly hack to work around the issue that
// the tag decls introduced by friend class declarations don't have an access
// specifier. Remove once this area of the code gets sorted out.
if (D->getAccess() != AS_none)
Record->setAccess(D->getAccess());
if (!IsInjectedClassName)
Record->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
// If the original function was part of a friend declaration,
// inherit its namespace state.
if (D->getFriendObjectKind())
Record->setObjectOfFriendDecl();
// Make sure that anonymous structs and unions are recorded.
if (D->isAnonymousStructOrUnion())
Record->setAnonymousStructOrUnion(true);
if (D->isLocalClass())
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Record);
// Forward the mangling number from the template to the instantiated decl.
SemaRef.Context.setManglingNumber(Record,
SemaRef.Context.getManglingNumber(D));
// See if the old tag was defined along with a declarator.
// If it did, mark the new tag as being associated with that declarator.
if (DeclaratorDecl *DD = SemaRef.Context.getDeclaratorForUnnamedTagDecl(D))
SemaRef.Context.addDeclaratorForUnnamedTagDecl(Record, DD);
// See if the old tag was defined along with a typedef.
// If it did, mark the new tag as being associated with that typedef.
if (TypedefNameDecl *TND = SemaRef.Context.getTypedefNameForUnnamedTagDecl(D))
SemaRef.Context.addTypedefNameForUnnamedTagDecl(Record, TND);
Owner->addDecl(Record);
// DR1484 clarifies that the members of a local class are instantiated as part
// of the instantiation of their enclosing entity.
if (D->isCompleteDefinition() && D->isLocalClass()) {
Sema::LocalEagerInstantiationScope LocalInstantiations(SemaRef);
SemaRef.InstantiateClass(D->getLocation(), Record, D, TemplateArgs,
TSK_ImplicitInstantiation,
/*Complain=*/true);
// For nested local classes, we will instantiate the members when we
// reach the end of the outermost (non-nested) local class.
if (!D->isCXXClassMember())
SemaRef.InstantiateClassMembers(D->getLocation(), Record, TemplateArgs,
TSK_ImplicitInstantiation);
// This class may have local implicit instantiations that need to be
// performed within this scope.
LocalInstantiations.perform();
}
SemaRef.DiagnoseUnusedNestedTypedefs(Record);
if (IsInjectedClassName)
assert(Record->isInjectedClassName() && "Broken injected-class-name");
return Record;
}
/// Adjust the given function type for an instantiation of the
/// given declaration, to cope with modifications to the function's type that
/// aren't reflected in the type-source information.
///
/// \param D The declaration we're instantiating.
/// \param TInfo The already-instantiated type.
static QualType adjustFunctionTypeForInstantiation(ASTContext &Context,
FunctionDecl *D,
TypeSourceInfo *TInfo) {
const FunctionProtoType *OrigFunc
= D->getType()->castAs<FunctionProtoType>();
const FunctionProtoType *NewFunc
= TInfo->getType()->castAs<FunctionProtoType>();
if (OrigFunc->getExtInfo() == NewFunc->getExtInfo())
return TInfo->getType();
FunctionProtoType::ExtProtoInfo NewEPI = NewFunc->getExtProtoInfo();
NewEPI.ExtInfo = OrigFunc->getExtInfo();
return Context.getFunctionType(NewFunc->getReturnType(),
NewFunc->getParamTypes(), NewEPI);
}
/// Normal class members are of more specific types and therefore
/// don't make it here. This function serves three purposes:
/// 1) instantiating function templates
/// 2) substituting friend and local function declarations
/// 3) substituting deduction guide declarations for nested class templates
Decl *TemplateDeclInstantiator::VisitFunctionDecl(
FunctionDecl *D, TemplateParameterList *TemplateParams,
RewriteKind FunctionRewriteKind) {
// Check whether there is already a function template specialization for
// this declaration.
FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
if (FunctionTemplate && !TemplateParams) {
ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
void *InsertPos = nullptr;
FunctionDecl *SpecFunc
= FunctionTemplate->findSpecialization(Innermost, InsertPos);
// If we already have a function template specialization, return it.
if (SpecFunc)
return SpecFunc;
}
bool isFriend;
if (FunctionTemplate)
isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
else
isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
bool MergeWithParentScope = (TemplateParams != nullptr) ||
Owner->isFunctionOrMethod() ||
!(isa<Decl>(Owner) &&
cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
ExplicitSpecifier InstantiatedExplicitSpecifier;
if (auto *DGuide = dyn_cast<CXXDeductionGuideDecl>(D)) {
InstantiatedExplicitSpecifier = SemaRef.instantiateExplicitSpecifier(
TemplateArgs, DGuide->getExplicitSpecifier());
if (InstantiatedExplicitSpecifier.isInvalid())
return nullptr;
}
SmallVector<ParmVarDecl *, 4> Params;
TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
if (!TInfo)
return nullptr;
QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
if (TemplateParams && TemplateParams->size()) {
auto *LastParam =
dyn_cast<TemplateTypeParmDecl>(TemplateParams->asArray().back());
if (LastParam && LastParam->isImplicit() &&
LastParam->hasTypeConstraint()) {
// In abbreviated templates, the type-constraints of invented template
// type parameters are instantiated with the function type, invalidating
// the TemplateParameterList which relied on the template type parameter
// not having a type constraint. Recreate the TemplateParameterList with
// the updated parameter list.
TemplateParams = TemplateParameterList::Create(
SemaRef.Context, TemplateParams->getTemplateLoc(),
TemplateParams->getLAngleLoc(), TemplateParams->asArray(),
TemplateParams->getRAngleLoc(), TemplateParams->getRequiresClause());
}
}
NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
if (QualifierLoc) {
QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
TemplateArgs);
if (!QualifierLoc)
return nullptr;
}
Expr *TrailingRequiresClause = D->getTrailingRequiresClause();
// If we're instantiating a local function declaration, put the result
// in the enclosing namespace; otherwise we need to find the instantiated
// context.
DeclContext *DC;
if (D->isLocalExternDecl()) {
DC = Owner;
SemaRef.adjustContextForLocalExternDecl(DC);
} else if (isFriend && QualifierLoc) {
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
DC = SemaRef.computeDeclContext(SS);
if (!DC) return nullptr;
} else {
DC = SemaRef.FindInstantiatedContext(D->getLocation(), D->getDeclContext(),
TemplateArgs);
}
DeclarationNameInfo NameInfo
= SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
if (FunctionRewriteKind != RewriteKind::None)
adjustForRewrite(FunctionRewriteKind, D, T, TInfo, NameInfo);
FunctionDecl *Function;
if (auto *DGuide = dyn_cast<CXXDeductionGuideDecl>(D)) {
Function = CXXDeductionGuideDecl::Create(
SemaRef.Context, DC, D->getInnerLocStart(),
InstantiatedExplicitSpecifier, NameInfo, T, TInfo,
D->getSourceRange().getEnd(), DGuide->getCorrespondingConstructor(),
DGuide->getDeductionCandidateKind());
Function->setAccess(D->getAccess());
} else {
Function = FunctionDecl::Create(
SemaRef.Context, DC, D->getInnerLocStart(), NameInfo, T, TInfo,
D->getCanonicalDecl()->getStorageClass(), D->UsesFPIntrin(),
D->isInlineSpecified(), D->hasWrittenPrototype(), D->getConstexprKind(),
TrailingRequiresClause);
Function->setFriendConstraintRefersToEnclosingTemplate(
D->FriendConstraintRefersToEnclosingTemplate());
Function->setRangeEnd(D->getSourceRange().getEnd());
}
if (D->isInlined())
Function->setImplicitlyInline();
if (QualifierLoc)
Function->setQualifierInfo(QualifierLoc);
if (D->isLocalExternDecl())
Function->setLocalExternDecl();
DeclContext *LexicalDC = Owner;
if (!isFriend && D->isOutOfLine() && !D->isLocalExternDecl()) {
assert(D->getDeclContext()->isFileContext());
LexicalDC = D->getDeclContext();
}
else if (D->isLocalExternDecl()) {
LexicalDC = SemaRef.CurContext;
}
Function->setLexicalDeclContext(LexicalDC);
// Attach the parameters
for (unsigned P = 0; P < Params.size(); ++P)
if (Params[P])
Params[P]->setOwningFunction(Function);
Function->setParams(Params);
if (TrailingRequiresClause)
Function->setTrailingRequiresClause(TrailingRequiresClause);
if (TemplateParams) {
// Our resulting instantiation is actually a function template, since we
// are substituting only the outer template parameters. For example, given
//
// template<typename T>
// struct X {
// template<typename U> friend void f(T, U);
// };
//
// X<int> x;
//
// We are instantiating the friend function template "f" within X<int>,
// which means substituting int for T, but leaving "f" as a friend function
// template.
// Build the function template itself.
FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, DC,
Function->getLocation(),
Function->getDeclName(),
TemplateParams, Function);
Function->setDescribedFunctionTemplate(FunctionTemplate);
FunctionTemplate->setLexicalDeclContext(LexicalDC);
if (isFriend && D->isThisDeclarationADefinition()) {
FunctionTemplate->setInstantiatedFromMemberTemplate(
D->getDescribedFunctionTemplate());
}
} else if (FunctionTemplate &&
SemaRef.CodeSynthesisContexts.back().Kind !=
Sema::CodeSynthesisContext::BuildingDeductionGuides) {
// Record this function template specialization.
ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
Function->setFunctionTemplateSpecialization(FunctionTemplate,
TemplateArgumentList::CreateCopy(SemaRef.Context,
Innermost),
/*InsertPos=*/nullptr);
} else if (isFriend && D->isThisDeclarationADefinition()) {
// Do not connect the friend to the template unless it's actually a
// definition. We don't want non-template functions to be marked as being
// template instantiations.
Function->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
} else if (!isFriend) {
// If this is not a function template, and this is not a friend (that is,
// this is a locally declared function), save the instantiation relationship
// for the purposes of constraint instantiation.
Function->setInstantiatedFromDecl(D);
}
if (isFriend) {
Function->setObjectOfFriendDecl();
if (FunctionTemplateDecl *FT = Function->getDescribedFunctionTemplate())
FT->setObjectOfFriendDecl();
}
if (InitFunctionInstantiation(Function, D))
Function->setInvalidDecl();
bool IsExplicitSpecialization = false;
LookupResult Previous(
SemaRef, Function->getDeclName(), SourceLocation(),
D->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
: Sema::LookupOrdinaryName,
D->isLocalExternDecl() ? RedeclarationKind::ForExternalRedeclaration
: SemaRef.forRedeclarationInCurContext());
if (DependentFunctionTemplateSpecializationInfo *DFTSI =
D->getDependentSpecializationInfo()) {
assert(isFriend && "dependent specialization info on "
"non-member non-friend function?");
// Instantiate the explicit template arguments.
TemplateArgumentListInfo ExplicitArgs;
if (const auto *ArgsWritten = DFTSI->TemplateArgumentsAsWritten) {
ExplicitArgs.setLAngleLoc(ArgsWritten->getLAngleLoc());
ExplicitArgs.setRAngleLoc(ArgsWritten->getRAngleLoc());
if (SemaRef.SubstTemplateArguments(ArgsWritten->arguments(), TemplateArgs,
ExplicitArgs))
return nullptr;
}
// Map the candidates for the primary template to their instantiations.
for (FunctionTemplateDecl *FTD : DFTSI->getCandidates()) {
if (NamedDecl *ND =
SemaRef.FindInstantiatedDecl(D->getLocation(), FTD, TemplateArgs))
Previous.addDecl(ND);
else
return nullptr;
}
if (SemaRef.CheckFunctionTemplateSpecialization(
Function,
DFTSI->TemplateArgumentsAsWritten ? &ExplicitArgs : nullptr,
Previous))
Function->setInvalidDecl();
IsExplicitSpecialization = true;
} else if (const ASTTemplateArgumentListInfo *ArgsWritten =
D->getTemplateSpecializationArgsAsWritten()) {
// The name of this function was written as a template-id.
SemaRef.LookupQualifiedName(Previous, DC);
// Instantiate the explicit template arguments.
TemplateArgumentListInfo ExplicitArgs(ArgsWritten->getLAngleLoc(),
ArgsWritten->getRAngleLoc());
if (SemaRef.SubstTemplateArguments(ArgsWritten->arguments(), TemplateArgs,
ExplicitArgs))
return nullptr;
if (SemaRef.CheckFunctionTemplateSpecialization(Function,
&ExplicitArgs,
Previous))
Function->setInvalidDecl();
IsExplicitSpecialization = true;
} else if (TemplateParams || !FunctionTemplate) {
// Look only into the namespace where the friend would be declared to
// find a previous declaration. This is the innermost enclosing namespace,
// as described in ActOnFriendFunctionDecl.
SemaRef.LookupQualifiedName(Previous, DC->getRedeclContext());
// In C++, the previous declaration we find might be a tag type
// (class or enum). In this case, the new declaration will hide the
// tag type. Note that this does not apply if we're declaring a
// typedef (C++ [dcl.typedef]p4).
if (Previous.isSingleTagDecl())
Previous.clear();
// Filter out previous declarations that don't match the scope. The only
// effect this has is to remove declarations found in inline namespaces
// for friend declarations with unqualified names.
if (isFriend && !QualifierLoc) {
SemaRef.FilterLookupForScope(Previous, DC, /*Scope=*/ nullptr,
/*ConsiderLinkage=*/ true,
QualifierLoc.hasQualifier());
}
}
// Per [temp.inst], default arguments in function declarations at local scope
// are instantiated along with the enclosing declaration. For example:
//
// template<typename T>
// void ft() {
// void f(int = []{ return T::value; }());
// }
// template void ft<int>(); // error: type 'int' cannot be used prior
// to '::' because it has no members
//
// The error is issued during instantiation of ft<int>() because substitution
// into the default argument fails; the default argument is instantiated even
// though it is never used.
if (Function->isLocalExternDecl()) {
for (ParmVarDecl *PVD : Function->parameters()) {
if (!PVD->hasDefaultArg())
continue;
if (SemaRef.SubstDefaultArgument(D->getInnerLocStart(), PVD, TemplateArgs)) {
// If substitution fails, the default argument is set to a
// RecoveryExpr that wraps the uninstantiated default argument so
// that downstream diagnostics are omitted.
Expr *UninstExpr = PVD->getUninstantiatedDefaultArg();
ExprResult ErrorResult = SemaRef.CreateRecoveryExpr(
UninstExpr->getBeginLoc(), UninstExpr->getEndLoc(),
{ UninstExpr }, UninstExpr->getType());
if (ErrorResult.isUsable())
PVD->setDefaultArg(ErrorResult.get());
}
}
}
SemaRef.CheckFunctionDeclaration(/*Scope*/ nullptr, Function, Previous,
IsExplicitSpecialization,
Function->isThisDeclarationADefinition());
// Check the template parameter list against the previous declaration. The
// goal here is to pick up default arguments added since the friend was
// declared; we know the template parameter lists match, since otherwise
// we would not have picked this template as the previous declaration.
if (isFriend && TemplateParams && FunctionTemplate->getPreviousDecl()) {
SemaRef.CheckTemplateParameterList(
TemplateParams,
FunctionTemplate->getPreviousDecl()->getTemplateParameters(),
Function->isThisDeclarationADefinition()
? Sema::TPC_FriendFunctionTemplateDefinition
: Sema::TPC_FriendFunctionTemplate);
}
// If we're introducing a friend definition after the first use, trigger
// instantiation.
// FIXME: If this is a friend function template definition, we should check
// to see if any specializations have been used.
if (isFriend && D->isThisDeclarationADefinition() && Function->isUsed(false)) {
if (MemberSpecializationInfo *MSInfo =
Function->getMemberSpecializationInfo()) {
if (MSInfo->getPointOfInstantiation().isInvalid()) {
SourceLocation Loc = D->getLocation(); // FIXME
MSInfo->setPointOfInstantiation(Loc);
SemaRef.PendingLocalImplicitInstantiations.push_back(
std::make_pair(Function, Loc));
}
}
}
if (D->isExplicitlyDefaulted()) {
if (SubstDefaultedFunction(Function, D))
return nullptr;
}
if (D->isDeleted())
SemaRef.SetDeclDeleted(Function, D->getLocation(), D->getDeletedMessage());
NamedDecl *PrincipalDecl =
(TemplateParams ? cast<NamedDecl>(FunctionTemplate) : Function);
// If this declaration lives in a different context from its lexical context,
// add it to the corresponding lookup table.
if (isFriend ||
(Function->isLocalExternDecl() && !Function->getPreviousDecl()))
DC->makeDeclVisibleInContext(PrincipalDecl);
if (Function->isOverloadedOperator() && !DC->isRecord() &&
PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
PrincipalDecl->setNonMemberOperator();
return Function;
}
Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(
CXXMethodDecl *D, TemplateParameterList *TemplateParams,
RewriteKind FunctionRewriteKind) {
FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
if (FunctionTemplate && !TemplateParams) {
// We are creating a function template specialization from a function
// template. Check whether there is already a function template
// specialization for this particular set of template arguments.
ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
void *InsertPos = nullptr;
FunctionDecl *SpecFunc
= FunctionTemplate->findSpecialization(Innermost, InsertPos);
// If we already have a function template specialization, return it.
if (SpecFunc)
return SpecFunc;
}
bool isFriend;
if (FunctionTemplate)
isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
else
isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
bool MergeWithParentScope = (TemplateParams != nullptr) ||
!(isa<Decl>(Owner) &&
cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
Sema::LambdaScopeForCallOperatorInstantiationRAII LambdaScope(
SemaRef, const_cast<CXXMethodDecl *>(D), TemplateArgs, Scope);
// Instantiate enclosing template arguments for friends.
SmallVector<TemplateParameterList *, 4> TempParamLists;
unsigned NumTempParamLists = 0;
if (isFriend && (NumTempParamLists = D->getNumTemplateParameterLists())) {
TempParamLists.resize(NumTempParamLists);
for (unsigned I = 0; I != NumTempParamLists; ++I) {
TemplateParameterList *TempParams = D->getTemplateParameterList(I);
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
TempParamLists[I] = InstParams;
}
}
auto InstantiatedExplicitSpecifier = ExplicitSpecifier::getFromDecl(D);
// deduction guides need this
const bool CouldInstantiate =
InstantiatedExplicitSpecifier.getExpr() == nullptr ||
!InstantiatedExplicitSpecifier.getExpr()->isValueDependent();
// Delay the instantiation of the explicit-specifier until after the
// constraints are checked during template argument deduction.
if (CouldInstantiate ||
SemaRef.CodeSynthesisContexts.back().Kind !=
Sema::CodeSynthesisContext::DeducedTemplateArgumentSubstitution) {
InstantiatedExplicitSpecifier = SemaRef.instantiateExplicitSpecifier(
TemplateArgs, InstantiatedExplicitSpecifier);
if (InstantiatedExplicitSpecifier.isInvalid())
return nullptr;
} else {
InstantiatedExplicitSpecifier.setKind(ExplicitSpecKind::Unresolved);
}
// Implicit destructors/constructors created for local classes in
// DeclareImplicit* (see SemaDeclCXX.cpp) might not have an associated TSI.
// Unfortunately there isn't enough context in those functions to
// conditionally populate the TSI without breaking non-template related use
// cases. Populate TSIs prior to calling SubstFunctionType to make sure we get
// a proper transformation.
if (cast<CXXRecordDecl>(D->getParent())->isLambda() &&
!D->getTypeSourceInfo() &&
isa<CXXConstructorDecl, CXXDestructorDecl>(D)) {
TypeSourceInfo *TSI =
SemaRef.Context.getTrivialTypeSourceInfo(D->getType());
D->setTypeSourceInfo(TSI);
}
SmallVector<ParmVarDecl *, 4> Params;
TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
if (!TInfo)
return nullptr;
QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
if (TemplateParams && TemplateParams->size()) {
auto *LastParam =
dyn_cast<TemplateTypeParmDecl>(TemplateParams->asArray().back());
if (LastParam && LastParam->isImplicit() &&
LastParam->hasTypeConstraint()) {
// In abbreviated templates, the type-constraints of invented template
// type parameters are instantiated with the function type, invalidating
// the TemplateParameterList which relied on the template type parameter
// not having a type constraint. Recreate the TemplateParameterList with
// the updated parameter list.
TemplateParams = TemplateParameterList::Create(
SemaRef.Context, TemplateParams->getTemplateLoc(),
TemplateParams->getLAngleLoc(), TemplateParams->asArray(),
TemplateParams->getRAngleLoc(), TemplateParams->getRequiresClause());
}
}
NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
if (QualifierLoc) {
QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
TemplateArgs);
if (!QualifierLoc)
return nullptr;
}
DeclContext *DC = Owner;
if (isFriend) {
if (QualifierLoc) {
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
DC = SemaRef.computeDeclContext(SS);
if (DC && SemaRef.RequireCompleteDeclContext(SS, DC))
return nullptr;
} else {
DC = SemaRef.FindInstantiatedContext(D->getLocation(),
D->getDeclContext(),
TemplateArgs);
}
if (!DC) return nullptr;
}
CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
Expr *TrailingRequiresClause = D->getTrailingRequiresClause();
DeclarationNameInfo NameInfo
= SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
if (FunctionRewriteKind != RewriteKind::None)
adjustForRewrite(FunctionRewriteKind, D, T, TInfo, NameInfo);
// Build the instantiated method declaration.
CXXMethodDecl *Method = nullptr;
SourceLocation StartLoc = D->getInnerLocStart();
if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
Method = CXXConstructorDecl::Create(
SemaRef.Context, Record, StartLoc, NameInfo, T, TInfo,
InstantiatedExplicitSpecifier, Constructor->UsesFPIntrin(),
Constructor->isInlineSpecified(), false,
Constructor->getConstexprKind(), InheritedConstructor(),
TrailingRequiresClause);
Method->setRangeEnd(Constructor->getEndLoc());
} else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) {
Method = CXXDestructorDecl::Create(
SemaRef.Context, Record, StartLoc, NameInfo, T, TInfo,
Destructor->UsesFPIntrin(), Destructor->isInlineSpecified(), false,
Destructor->getConstexprKind(), TrailingRequiresClause);
Method->setIneligibleOrNotSelected(true);
Method->setRangeEnd(Destructor->getEndLoc());
Method->setDeclName(SemaRef.Context.DeclarationNames.getCXXDestructorName(
SemaRef.Context.getCanonicalType(
SemaRef.Context.getTypeDeclType(Record))));
} else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(D)) {
Method = CXXConversionDecl::Create(
SemaRef.Context, Record, StartLoc, NameInfo, T, TInfo,
Conversion->UsesFPIntrin(), Conversion->isInlineSpecified(),
InstantiatedExplicitSpecifier, Conversion->getConstexprKind(),
Conversion->getEndLoc(), TrailingRequiresClause);
} else {
StorageClass SC = D->isStatic() ? SC_Static : SC_None;
Method = CXXMethodDecl::Create(
SemaRef.Context, Record, StartLoc, NameInfo, T, TInfo, SC,
D->UsesFPIntrin(), D->isInlineSpecified(), D->getConstexprKind(),
D->getEndLoc(), TrailingRequiresClause);
}
if (D->isInlined())
Method->setImplicitlyInline();
if (QualifierLoc)
Method->setQualifierInfo(QualifierLoc);
if (TemplateParams) {
// Our resulting instantiation is actually a function template, since we
// are substituting only the outer template parameters. For example, given
//
// template<typename T>
// struct X {
// template<typename U> void f(T, U);
// };
//
// X<int> x;
//
// We are instantiating the member template "f" within X<int>, which means
// substituting int for T, but leaving "f" as a member function template.
// Build the function template itself.
FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, Record,
Method->getLocation(),
Method->getDeclName(),
TemplateParams, Method);
if (isFriend) {
FunctionTemplate->setLexicalDeclContext(Owner);
FunctionTemplate->setObjectOfFriendDecl();
} else if (D->isOutOfLine())
FunctionTemplate->setLexicalDeclContext(D->getLexicalDeclContext());
Method->setDescribedFunctionTemplate(FunctionTemplate);
} else if (FunctionTemplate) {
// Record this function template specialization.
ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
Method->setFunctionTemplateSpecialization(FunctionTemplate,
TemplateArgumentList::CreateCopy(SemaRef.Context,
Innermost),
/*InsertPos=*/nullptr);
} else if (!isFriend) {
// Record that this is an instantiation of a member function.
Method->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
}
// If we are instantiating a member function defined
// out-of-line, the instantiation will have the same lexical
// context (which will be a namespace scope) as the template.
if (isFriend) {
if (NumTempParamLists)
Method->setTemplateParameterListsInfo(
SemaRef.Context,
llvm::ArrayRef(TempParamLists.data(), NumTempParamLists));
Method->setLexicalDeclContext(Owner);
Method->setObjectOfFriendDecl();
} else if (D->isOutOfLine())
Method->setLexicalDeclContext(D->getLexicalDeclContext());
// Attach the parameters
for (unsigned P = 0; P < Params.size(); ++P)
Params[P]->setOwningFunction(Method);
Method->setParams(Params);
if (InitMethodInstantiation(Method, D))
Method->setInvalidDecl();
LookupResult Previous(SemaRef, NameInfo, Sema::LookupOrdinaryName,
RedeclarationKind::ForExternalRedeclaration);
bool IsExplicitSpecialization = false;
// If the name of this function was written as a template-id, instantiate
// the explicit template arguments.
if (DependentFunctionTemplateSpecializationInfo *DFTSI =
D->getDependentSpecializationInfo()) {
// Instantiate the explicit template arguments.
TemplateArgumentListInfo ExplicitArgs;
if (const auto *ArgsWritten = DFTSI->TemplateArgumentsAsWritten) {
ExplicitArgs.setLAngleLoc(ArgsWritten->getLAngleLoc());
ExplicitArgs.setRAngleLoc(ArgsWritten->getRAngleLoc());
if (SemaRef.SubstTemplateArguments(ArgsWritten->arguments(), TemplateArgs,
ExplicitArgs))
return nullptr;
}
// Map the candidates for the primary template to their instantiations.
for (FunctionTemplateDecl *FTD : DFTSI->getCandidates()) {
if (NamedDecl *ND =
SemaRef.FindInstantiatedDecl(D->getLocation(), FTD, TemplateArgs))
Previous.addDecl(ND);
else
return nullptr;
}
if (SemaRef.CheckFunctionTemplateSpecialization(
Method, DFTSI->TemplateArgumentsAsWritten ? &ExplicitArgs : nullptr,
Previous))
Method->setInvalidDecl();
IsExplicitSpecialization = true;
} else if (const ASTTemplateArgumentListInfo *ArgsWritten =
D->getTemplateSpecializationArgsAsWritten()) {
SemaRef.LookupQualifiedName(Previous, DC);
TemplateArgumentListInfo ExplicitArgs(ArgsWritten->getLAngleLoc(),
ArgsWritten->getRAngleLoc());
if (SemaRef.SubstTemplateArguments(ArgsWritten->arguments(), TemplateArgs,
ExplicitArgs))
return nullptr;
if (SemaRef.CheckFunctionTemplateSpecialization(Method,
&ExplicitArgs,
Previous))
Method->setInvalidDecl();
IsExplicitSpecialization = true;
} else if (!FunctionTemplate || TemplateParams || isFriend) {
SemaRef.LookupQualifiedName(Previous, Record);
// In C++, the previous declaration we find might be a tag type
// (class or enum). In this case, the new declaration will hide the
// tag type. Note that this does not apply if we're declaring a
// typedef (C++ [dcl.typedef]p4).
if (Previous.isSingleTagDecl())
Previous.clear();
}
// Per [temp.inst], default arguments in member functions of local classes
// are instantiated along with the member function declaration. For example:
//
// template<typename T>
// void ft() {
// struct lc {
// int operator()(int p = []{ return T::value; }());
// };
// }
// template void ft<int>(); // error: type 'int' cannot be used prior
// to '::'because it has no members
//
// The error is issued during instantiation of ft<int>()::lc::operator()
// because substitution into the default argument fails; the default argument
// is instantiated even though it is never used.
if (D->isInLocalScopeForInstantiation()) {
for (unsigned P = 0; P < Params.size(); ++P) {
if (!Params[P]->hasDefaultArg())
continue;
if (SemaRef.SubstDefaultArgument(StartLoc, Params[P], TemplateArgs)) {
// If substitution fails, the default argument is set to a
// RecoveryExpr that wraps the uninstantiated default argument so
// that downstream diagnostics are omitted.
Expr *UninstExpr = Params[P]->getUninstantiatedDefaultArg();
ExprResult ErrorResult = SemaRef.CreateRecoveryExpr(
UninstExpr->getBeginLoc(), UninstExpr->getEndLoc(),
{ UninstExpr }, UninstExpr->getType());
if (ErrorResult.isUsable())
Params[P]->setDefaultArg(ErrorResult.get());
}
}
}
SemaRef.CheckFunctionDeclaration(nullptr, Method, Previous,
IsExplicitSpecialization,
Method->isThisDeclarationADefinition());
if (D->isPureVirtual())
SemaRef.CheckPureMethod(Method, SourceRange());
// Propagate access. For a non-friend declaration, the access is
// whatever we're propagating from. For a friend, it should be the
// previous declaration we just found.
if (isFriend && Method->getPreviousDecl())
Method->setAccess(Method->getPreviousDecl()->getAccess());
else
Method->setAccess(D->getAccess());
if (FunctionTemplate)
FunctionTemplate->setAccess(Method->getAccess());
SemaRef.CheckOverrideControl(Method);
// If a function is defined as defaulted or deleted, mark it as such now.
if (D->isExplicitlyDefaulted()) {
if (SubstDefaultedFunction(Method, D))
return nullptr;
}
if (D->isDeletedAsWritten())
SemaRef.SetDeclDeleted(Method, Method->getLocation(),
D->getDeletedMessage());
// If this is an explicit specialization, mark the implicitly-instantiated
// template specialization as being an explicit specialization too.
// FIXME: Is this necessary?
if (IsExplicitSpecialization && !isFriend)
SemaRef.CompleteMemberSpecialization(Method, Previous);
// If the method is a special member function, we need to mark it as
// ineligible so that Owner->addDecl() won't mark the class as non trivial.
// At the end of the class instantiation, we calculate eligibility again and
// then we adjust trivility if needed.
// We need this check to happen only after the method parameters are set,
// because being e.g. a copy constructor depends on the instantiated
// arguments.
if (auto *Constructor = dyn_cast<CXXConstructorDecl>(Method)) {
if (Constructor->isDefaultConstructor() ||
Constructor->isCopyOrMoveConstructor())
Method->setIneligibleOrNotSelected(true);
} else if (Method->isCopyAssignmentOperator() ||
Method->isMoveAssignmentOperator()) {
Method->setIneligibleOrNotSelected(true);
}
// If there's a function template, let our caller handle it.
if (FunctionTemplate) {
// do nothing
// Don't hide a (potentially) valid declaration with an invalid one.
} else if (Method->isInvalidDecl() && !Previous.empty()) {
// do nothing
// Otherwise, check access to friends and make them visible.
} else if (isFriend) {
// We only need to re-check access for methods which we didn't
// manage to match during parsing.
if (!D->getPreviousDecl())
SemaRef.CheckFriendAccess(Method);
Record->makeDeclVisibleInContext(Method);
// Otherwise, add the declaration. We don't need to do this for
// class-scope specializations because we'll have matched them with
// the appropriate template.
} else {
Owner->addDecl(Method);
}
// PR17480: Honor the used attribute to instantiate member function
// definitions
if (Method->hasAttr<UsedAttr>()) {
if (const auto *A = dyn_cast<CXXRecordDecl>(Owner)) {
SourceLocation Loc;
if (const MemberSpecializationInfo *MSInfo =
A->getMemberSpecializationInfo())
Loc = MSInfo->getPointOfInstantiation();
else if (const auto *Spec = dyn_cast<ClassTemplateSpecializationDecl>(A))
Loc = Spec->getPointOfInstantiation();
SemaRef.MarkFunctionReferenced(Loc, Method);
}
}
return Method;
}
Decl *TemplateDeclInstantiator::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
return VisitCXXMethodDecl(D);
}
Decl *TemplateDeclInstantiator::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
return VisitCXXMethodDecl(D);
}
Decl *TemplateDeclInstantiator::VisitCXXConversionDecl(CXXConversionDecl *D) {
return VisitCXXMethodDecl(D);
}
Decl *TemplateDeclInstantiator::VisitParmVarDecl(ParmVarDecl *D) {
return SemaRef.SubstParmVarDecl(D, TemplateArgs, /*indexAdjustment*/ 0,
std::nullopt,
/*ExpectParameterPack=*/false);
}
Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
TemplateTypeParmDecl *D) {
assert(D->getTypeForDecl()->isTemplateTypeParmType());
std::optional<unsigned> NumExpanded;
if (const TypeConstraint *TC = D->getTypeConstraint()) {
if (D->isPackExpansion() && !D->isExpandedParameterPack()) {
assert(TC->getTemplateArgsAsWritten() &&
"type parameter can only be an expansion when explicit arguments "
"are specified");
// The template type parameter pack's type is a pack expansion of types.
// Determine whether we need to expand this parameter pack into separate
// types.
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
for (auto &ArgLoc : TC->getTemplateArgsAsWritten()->arguments())
SemaRef.collectUnexpandedParameterPacks(ArgLoc, Unexpanded);
// Determine whether the set of unexpanded parameter packs can and should
// be expanded.
bool Expand = true;
bool RetainExpansion = false;
if (SemaRef.CheckParameterPacksForExpansion(
cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
->getEllipsisLoc(),
SourceRange(TC->getConceptNameLoc(),
TC->hasExplicitTemplateArgs() ?
TC->getTemplateArgsAsWritten()->getRAngleLoc() :
TC->getConceptNameInfo().getEndLoc()),
Unexpanded, TemplateArgs, Expand, RetainExpansion, NumExpanded))
return nullptr;
}
}
TemplateTypeParmDecl *Inst = TemplateTypeParmDecl::Create(
SemaRef.Context, Owner, D->getBeginLoc(), D->getLocation(),
D->getDepth() - TemplateArgs.getNumSubstitutedLevels(), D->getIndex(),
D->getIdentifier(), D->wasDeclaredWithTypename(), D->isParameterPack(),
D->hasTypeConstraint(), NumExpanded);
Inst->setAccess(AS_public);
Inst->setImplicit(D->isImplicit());
if (auto *TC = D->getTypeConstraint()) {
if (!D->isImplicit()) {
// Invented template parameter type constraints will be instantiated
// with the corresponding auto-typed parameter as it might reference
// other parameters.
if (SemaRef.SubstTypeConstraint(Inst, TC, TemplateArgs,
EvaluateConstraints))
return nullptr;
}
}
if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
TypeSourceInfo *InstantiatedDefaultArg =
SemaRef.SubstType(D->getDefaultArgumentInfo(), TemplateArgs,
D->getDefaultArgumentLoc(), D->getDeclName());
if (InstantiatedDefaultArg)
Inst->setDefaultArgument(InstantiatedDefaultArg);
}
// Introduce this template parameter's instantiation into the instantiation
// scope.
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Inst);
return Inst;
}
Decl *TemplateDeclInstantiator::VisitNonTypeTemplateParmDecl(
NonTypeTemplateParmDecl *D) {
// Substitute into the type of the non-type template parameter.
TypeLoc TL = D->getTypeSourceInfo()->getTypeLoc();
SmallVector<TypeSourceInfo *, 4> ExpandedParameterPackTypesAsWritten;
SmallVector<QualType, 4> ExpandedParameterPackTypes;
bool IsExpandedParameterPack = false;
TypeSourceInfo *DI;
QualType T;
bool Invalid = false;
if (D->isExpandedParameterPack()) {
// The non-type template parameter pack is an already-expanded pack
// expansion of types. Substitute into each of the expanded types.
ExpandedParameterPackTypes.reserve(D->getNumExpansionTypes());
ExpandedParameterPackTypesAsWritten.reserve(D->getNumExpansionTypes());
for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
TypeSourceInfo *NewDI =
SemaRef.SubstType(D->getExpansionTypeSourceInfo(I), TemplateArgs,
D->getLocation(), D->getDeclName());
if (!NewDI)
return nullptr;
QualType NewT =
SemaRef.CheckNonTypeTemplateParameterType(NewDI, D->getLocation());
if (NewT.isNull())
return nullptr;
ExpandedParameterPackTypesAsWritten.push_back(NewDI);
ExpandedParameterPackTypes.push_back(NewT);
}
IsExpandedParameterPack = true;
DI = D->getTypeSourceInfo();
T = DI->getType();
} else if (D->isPackExpansion()) {
// The non-type template parameter pack's type is a pack expansion of types.
// Determine whether we need to expand this parameter pack into separate
// types.
PackExpansionTypeLoc Expansion = TL.castAs<PackExpansionTypeLoc>();
TypeLoc Pattern = Expansion.getPatternLoc();
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
SemaRef.collectUnexpandedParameterPacks(Pattern, Unexpanded);
// Determine whether the set of unexpanded parameter packs can and should
// be expanded.
bool Expand = true;
bool RetainExpansion = false;
std::optional<unsigned> OrigNumExpansions =
Expansion.getTypePtr()->getNumExpansions();
std::optional<unsigned> NumExpansions = OrigNumExpansions;
if (SemaRef.CheckParameterPacksForExpansion(Expansion.getEllipsisLoc(),
Pattern.getSourceRange(),
Unexpanded,
TemplateArgs,
Expand, RetainExpansion,
NumExpansions))
return nullptr;
if (Expand) {
for (unsigned I = 0; I != *NumExpansions; ++I) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
TypeSourceInfo *NewDI = SemaRef.SubstType(Pattern, TemplateArgs,
D->getLocation(),
D->getDeclName());
if (!NewDI)
return nullptr;
QualType NewT =
SemaRef.CheckNonTypeTemplateParameterType(NewDI, D->getLocation());
if (NewT.isNull())
return nullptr;
ExpandedParameterPackTypesAsWritten.push_back(NewDI);
ExpandedParameterPackTypes.push_back(NewT);
}
// Note that we have an expanded parameter pack. The "type" of this
// expanded parameter pack is the original expansion type, but callers
// will end up using the expanded parameter pack types for type-checking.
IsExpandedParameterPack = true;
DI = D->getTypeSourceInfo();
T = DI->getType();
} else {
// We cannot fully expand the pack expansion now, so substitute into the
// pattern and create a new pack expansion type.
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
TypeSourceInfo *NewPattern = SemaRef.SubstType(Pattern, TemplateArgs,
D->getLocation(),
D->getDeclName());
if (!NewPattern)
return nullptr;
SemaRef.CheckNonTypeTemplateParameterType(NewPattern, D->getLocation());
DI = SemaRef.CheckPackExpansion(NewPattern, Expansion.getEllipsisLoc(),
NumExpansions);
if (!DI)
return nullptr;
T = DI->getType();
}
} else {
// Simple case: substitution into a parameter that is not a parameter pack.
DI = SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
D->getLocation(), D->getDeclName());
if (!DI)
return nullptr;
// Check that this type is acceptable for a non-type template parameter.
T = SemaRef.CheckNonTypeTemplateParameterType(DI, D->getLocation());
if (T.isNull()) {
T = SemaRef.Context.IntTy;
Invalid = true;
}
}
NonTypeTemplateParmDecl *Param;
if (IsExpandedParameterPack)
Param = NonTypeTemplateParmDecl::Create(
SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
D->getPosition(), D->getIdentifier(), T, DI, ExpandedParameterPackTypes,
ExpandedParameterPackTypesAsWritten);
else
Param = NonTypeTemplateParmDecl::Create(
SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
D->getPosition(), D->getIdentifier(), T, D->isParameterPack(), DI);
if (AutoTypeLoc AutoLoc = DI->getTypeLoc().getContainedAutoTypeLoc())
if (AutoLoc.isConstrained()) {
SourceLocation EllipsisLoc;
if (IsExpandedParameterPack)
EllipsisLoc =
DI->getTypeLoc().getAs<PackExpansionTypeLoc>().getEllipsisLoc();
else if (auto *Constraint = dyn_cast_if_present<CXXFoldExpr>(
D->getPlaceholderTypeConstraint()))
EllipsisLoc = Constraint->getEllipsisLoc();
// Note: We attach the uninstantiated constriant here, so that it can be
// instantiated relative to the top level, like all our other
// constraints.
if (SemaRef.AttachTypeConstraint(AutoLoc, /*NewConstrainedParm=*/Param,
/*OrigConstrainedParm=*/D, EllipsisLoc))
Invalid = true;
}
Param->setAccess(AS_public);
Param->setImplicit(D->isImplicit());
if (Invalid)
Param->setInvalidDecl();
if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
EnterExpressionEvaluationContext ConstantEvaluated(
SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
ExprResult Value = SemaRef.SubstExpr(D->getDefaultArgument(), TemplateArgs);
if (!Value.isInvalid())
Param->setDefaultArgument(Value.get());
}
// Introduce this template parameter's instantiation into the instantiation
// scope.
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
return Param;
}
static void collectUnexpandedParameterPacks(
Sema &S,
TemplateParameterList *Params,
SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) {
for (const auto &P : *Params) {
if (P->isTemplateParameterPack())
continue;
if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P))
S.collectUnexpandedParameterPacks(NTTP->getTypeSourceInfo()->getTypeLoc(),
Unexpanded);
if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(P))
collectUnexpandedParameterPacks(S, TTP->getTemplateParameters(),
Unexpanded);
}
}
Decl *
TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
TemplateTemplateParmDecl *D) {
// Instantiate the template parameter list of the template template parameter.
TemplateParameterList *TempParams = D->getTemplateParameters();
TemplateParameterList *InstParams;
SmallVector<TemplateParameterList*, 8> ExpandedParams;
bool IsExpandedParameterPack = false;
if (D->isExpandedParameterPack()) {
// The template template parameter pack is an already-expanded pack
// expansion of template parameters. Substitute into each of the expanded
// parameters.
ExpandedParams.reserve(D->getNumExpansionTemplateParameters());
for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
I != N; ++I) {
LocalInstantiationScope Scope(SemaRef);
TemplateParameterList *Expansion =
SubstTemplateParams(D->getExpansionTemplateParameters(I));
if (!Expansion)
return nullptr;
ExpandedParams.push_back(Expansion);
}
IsExpandedParameterPack = true;
InstParams = TempParams;
} else if (D->isPackExpansion()) {
// The template template parameter pack expands to a pack of template
// template parameters. Determine whether we need to expand this parameter
// pack into separate parameters.
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
collectUnexpandedParameterPacks(SemaRef, D->getTemplateParameters(),
Unexpanded);
// Determine whether the set of unexpanded parameter packs can and should
// be expanded.
bool Expand = true;
bool RetainExpansion = false;
std::optional<unsigned> NumExpansions;
if (SemaRef.CheckParameterPacksForExpansion(D->getLocation(),
TempParams->getSourceRange(),
Unexpanded,
TemplateArgs,
Expand, RetainExpansion,
NumExpansions))
return nullptr;
if (Expand) {
for (unsigned I = 0; I != *NumExpansions; ++I) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
LocalInstantiationScope Scope(SemaRef);
TemplateParameterList *Expansion = SubstTemplateParams(TempParams);
if (!Expansion)
return nullptr;
ExpandedParams.push_back(Expansion);
}
// Note that we have an expanded parameter pack. The "type" of this
// expanded parameter pack is the original expansion type, but callers
// will end up using the expanded parameter pack types for type-checking.
IsExpandedParameterPack = true;
InstParams = TempParams;
} else {
// We cannot fully expand the pack expansion now, so just substitute
// into the pattern.
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
LocalInstantiationScope Scope(SemaRef);
InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
}
} else {
// Perform the actual substitution of template parameters within a new,
// local instantiation scope.
LocalInstantiationScope Scope(SemaRef);
InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
}
// Build the template template parameter.
TemplateTemplateParmDecl *Param;
if (IsExpandedParameterPack)
Param = TemplateTemplateParmDecl::Create(
SemaRef.Context, Owner, D->getLocation(),
D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
D->getPosition(), D->getIdentifier(), D->wasDeclaredWithTypename(),
InstParams, ExpandedParams);
else
Param = TemplateTemplateParmDecl::Create(
SemaRef.Context, Owner, D->getLocation(),
D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
D->getPosition(), D->isParameterPack(), D->getIdentifier(),
D->wasDeclaredWithTypename(), InstParams);
if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
NestedNameSpecifierLoc QualifierLoc =
D->getDefaultArgument().getTemplateQualifierLoc();
QualifierLoc =
SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgs);
TemplateName TName = SemaRef.SubstTemplateName(
QualifierLoc, D->getDefaultArgument().getArgument().getAsTemplate(),
D->getDefaultArgument().getTemplateNameLoc(), TemplateArgs);
if (!TName.isNull())
Param->setDefaultArgument(
SemaRef.Context,
TemplateArgumentLoc(SemaRef.Context, TemplateArgument(TName),
D->getDefaultArgument().getTemplateQualifierLoc(),
D->getDefaultArgument().getTemplateNameLoc()));
}
Param->setAccess(AS_public);
Param->setImplicit(D->isImplicit());
// Introduce this template parameter's instantiation into the instantiation
// scope.
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
return Param;
}
Decl *TemplateDeclInstantiator::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
// Using directives are never dependent (and never contain any types or
// expressions), so they require no explicit instantiation work.
UsingDirectiveDecl *Inst
= UsingDirectiveDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getNamespaceKeyLocation(),
D->getQualifierLoc(),
D->getIdentLocation(),
D->getNominatedNamespace(),
D->getCommonAncestor());
// Add the using directive to its declaration context
// only if this is not a function or method.
if (!Owner->isFunctionOrMethod())
Owner->addDecl(Inst);
return Inst;
}
Decl *TemplateDeclInstantiator::VisitBaseUsingDecls(BaseUsingDecl *D,
BaseUsingDecl *Inst,
LookupResult *Lookup) {
bool isFunctionScope = Owner->isFunctionOrMethod();
for (auto *Shadow : D->shadows()) {
// FIXME: UsingShadowDecl doesn't preserve its immediate target, so
// reconstruct it in the case where it matters. Hm, can we extract it from
// the DeclSpec when parsing and save it in the UsingDecl itself?
NamedDecl *OldTarget = Shadow->getTargetDecl();
if (auto *CUSD = dyn_cast<ConstructorUsingShadowDecl>(Shadow))
if (auto *BaseShadow = CUSD->getNominatedBaseClassShadowDecl())
OldTarget = BaseShadow;
NamedDecl *InstTarget = nullptr;
if (auto *EmptyD =
dyn_cast<UnresolvedUsingIfExistsDecl>(Shadow->getTargetDecl())) {
InstTarget = UnresolvedUsingIfExistsDecl::Create(
SemaRef.Context, Owner, EmptyD->getLocation(), EmptyD->getDeclName());
} else {
InstTarget = cast_or_null<NamedDecl>(SemaRef.FindInstantiatedDecl(
Shadow->getLocation(), OldTarget, TemplateArgs));
}
if (!InstTarget)
return nullptr;
UsingShadowDecl *PrevDecl = nullptr;
if (Lookup &&
SemaRef.CheckUsingShadowDecl(Inst, InstTarget, *Lookup, PrevDecl))
continue;
if (UsingShadowDecl *OldPrev = getPreviousDeclForInstantiation(Shadow))
PrevDecl = cast_or_null<UsingShadowDecl>(SemaRef.FindInstantiatedDecl(
Shadow->getLocation(), OldPrev, TemplateArgs));
UsingShadowDecl *InstShadow = SemaRef.BuildUsingShadowDecl(
/*Scope*/ nullptr, Inst, InstTarget, PrevDecl);
SemaRef.Context.setInstantiatedFromUsingShadowDecl(InstShadow, Shadow);
if (isFunctionScope)
SemaRef.CurrentInstantiationScope->InstantiatedLocal(Shadow, InstShadow);
}
return Inst;
}
Decl *TemplateDeclInstantiator::VisitUsingDecl(UsingDecl *D) {
// The nested name specifier may be dependent, for example
// template <typename T> struct t {
// struct s1 { T f1(); };
// struct s2 : s1 { using s1::f1; };
// };
// template struct t<int>;
// Here, in using s1::f1, s1 refers to t<T>::s1;
// we need to substitute for t<int>::s1.
NestedNameSpecifierLoc QualifierLoc
= SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
TemplateArgs);
if (!QualifierLoc)
return nullptr;
// For an inheriting constructor declaration, the name of the using
// declaration is the name of a constructor in this class, not in the
// base class.
DeclarationNameInfo NameInfo = D->getNameInfo();
if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName)
if (auto *RD = dyn_cast<CXXRecordDecl>(SemaRef.CurContext))
NameInfo.setName(SemaRef.Context.DeclarationNames.getCXXConstructorName(
SemaRef.Context.getCanonicalType(SemaRef.Context.getRecordType(RD))));
// We only need to do redeclaration lookups if we're in a class scope (in
// fact, it's not really even possible in non-class scopes).
bool CheckRedeclaration = Owner->isRecord();
LookupResult Prev(SemaRef, NameInfo, Sema::LookupUsingDeclName,
RedeclarationKind::ForVisibleRedeclaration);
UsingDecl *NewUD = UsingDecl::Create(SemaRef.Context, Owner,
D->getUsingLoc(),
QualifierLoc,
NameInfo,
D->hasTypename());
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
if (CheckRedeclaration) {
Prev.setHideTags(false);
SemaRef.LookupQualifiedName(Prev, Owner);
// Check for invalid redeclarations.
if (SemaRef.CheckUsingDeclRedeclaration(D->getUsingLoc(),
D->hasTypename(), SS,
D->getLocation(), Prev))
NewUD->setInvalidDecl();
}
if (!NewUD->isInvalidDecl() &&
SemaRef.CheckUsingDeclQualifier(D->getUsingLoc(), D->hasTypename(), SS,
NameInfo, D->getLocation(), nullptr, D))
NewUD->setInvalidDecl();
SemaRef.Context.setInstantiatedFromUsingDecl(NewUD, D);
NewUD->setAccess(D->getAccess());
Owner->addDecl(NewUD);
// Don't process the shadow decls for an invalid decl.
if (NewUD->isInvalidDecl())
return NewUD;
// If the using scope was dependent, or we had dependent bases, we need to
// recheck the inheritance
if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName)
SemaRef.CheckInheritingConstructorUsingDecl(NewUD);
return VisitBaseUsingDecls(D, NewUD, CheckRedeclaration ? &Prev : nullptr);
}
Decl *TemplateDeclInstantiator::VisitUsingEnumDecl(UsingEnumDecl *D) {
// Cannot be a dependent type, but still could be an instantiation
EnumDecl *EnumD = cast_or_null<EnumDecl>(SemaRef.FindInstantiatedDecl(
D->getLocation(), D->getEnumDecl(), TemplateArgs));
if (SemaRef.RequireCompleteEnumDecl(EnumD, EnumD->getLocation()))
return nullptr;
TypeSourceInfo *TSI = SemaRef.SubstType(D->getEnumType(), TemplateArgs,
D->getLocation(), D->getDeclName());
UsingEnumDecl *NewUD =
UsingEnumDecl::Create(SemaRef.Context, Owner, D->getUsingLoc(),
D->getEnumLoc(), D->getLocation(), TSI);
SemaRef.Context.setInstantiatedFromUsingEnumDecl(NewUD, D);
NewUD->setAccess(D->getAccess());
Owner->addDecl(NewUD);
// Don't process the shadow decls for an invalid decl.
if (NewUD->isInvalidDecl())
return NewUD;
// We don't have to recheck for duplication of the UsingEnumDecl itself, as it
// cannot be dependent, and will therefore have been checked during template
// definition.
return VisitBaseUsingDecls(D, NewUD, nullptr);
}
Decl *TemplateDeclInstantiator::VisitUsingShadowDecl(UsingShadowDecl *D) {
// Ignore these; we handle them in bulk when processing the UsingDecl.
return nullptr;
}
Decl *TemplateDeclInstantiator::VisitConstructorUsingShadowDecl(
ConstructorUsingShadowDecl *D) {
// Ignore these; we handle them in bulk when processing the UsingDecl.
return nullptr;
}
template <typename T>
Decl *TemplateDeclInstantiator::instantiateUnresolvedUsingDecl(
T *D, bool InstantiatingPackElement) {
// If this is a pack expansion, expand it now.
if (D->isPackExpansion() && !InstantiatingPackElement) {
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
SemaRef.collectUnexpandedParameterPacks(D->getQualifierLoc(), Unexpanded);
SemaRef.collectUnexpandedParameterPacks(D->getNameInfo(), Unexpanded);
// Determine whether the set of unexpanded parameter packs can and should
// be expanded.
bool Expand = true;
bool RetainExpansion = false;
std::optional<unsigned> NumExpansions;
if (SemaRef.CheckParameterPacksForExpansion(
D->getEllipsisLoc(), D->getSourceRange(), Unexpanded, TemplateArgs,
Expand, RetainExpansion, NumExpansions))
return nullptr;
// This declaration cannot appear within a function template signature,
// so we can't have a partial argument list for a parameter pack.
assert(!RetainExpansion &&
"should never need to retain an expansion for UsingPackDecl");
if (!Expand) {
// We cannot fully expand the pack expansion now, so substitute into the
// pattern and create a new pack expansion.
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
return instantiateUnresolvedUsingDecl(D, true);
}
// Within a function, we don't have any normal way to check for conflicts
// between shadow declarations from different using declarations in the
// same pack expansion, but this is always ill-formed because all expansions
// must produce (conflicting) enumerators.
//
// Sadly we can't just reject this in the template definition because it
// could be valid if the pack is empty or has exactly one expansion.
if (D->getDeclContext()->isFunctionOrMethod() && *NumExpansions > 1) {
SemaRef.Diag(D->getEllipsisLoc(),
diag::err_using_decl_redeclaration_expansion);
return nullptr;
}
// Instantiate the slices of this pack and build a UsingPackDecl.
SmallVector<NamedDecl*, 8> Expansions;
for (unsigned I = 0; I != *NumExpansions; ++I) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
Decl *Slice = instantiateUnresolvedUsingDecl(D, true);
if (!Slice)
return nullptr;
// Note that we can still get unresolved using declarations here, if we
// had arguments for all packs but the pattern also contained other
// template arguments (this only happens during partial substitution, eg
// into the body of a generic lambda in a function template).
Expansions.push_back(cast<NamedDecl>(Slice));
}
auto *NewD = SemaRef.BuildUsingPackDecl(D, Expansions);
if (isDeclWithinFunction(D))
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewD);
return NewD;
}
UnresolvedUsingTypenameDecl *TD = dyn_cast<UnresolvedUsingTypenameDecl>(D);
SourceLocation TypenameLoc = TD ? TD->getTypenameLoc() : SourceLocation();
NestedNameSpecifierLoc QualifierLoc
= SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
TemplateArgs);
if (!QualifierLoc)
return nullptr;
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
DeclarationNameInfo NameInfo
= SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
// Produce a pack expansion only if we're not instantiating a particular
// slice of a pack expansion.
bool InstantiatingSlice = D->getEllipsisLoc().isValid() &&
SemaRef.ArgumentPackSubstitutionIndex != -1;
SourceLocation EllipsisLoc =
InstantiatingSlice ? SourceLocation() : D->getEllipsisLoc();
bool IsUsingIfExists = D->template hasAttr<UsingIfExistsAttr>();
NamedDecl *UD = SemaRef.BuildUsingDeclaration(
/*Scope*/ nullptr, D->getAccess(), D->getUsingLoc(),
/*HasTypename*/ TD, TypenameLoc, SS, NameInfo, EllipsisLoc,
ParsedAttributesView(),
/*IsInstantiation*/ true, IsUsingIfExists);
if (UD) {
SemaRef.InstantiateAttrs(TemplateArgs, D, UD);
SemaRef.Context.setInstantiatedFromUsingDecl(UD, D);
}
return UD;
}
Decl *TemplateDeclInstantiator::VisitUnresolvedUsingTypenameDecl(
UnresolvedUsingTypenameDecl *D) {
return instantiateUnresolvedUsingDecl(D);
}
Decl *TemplateDeclInstantiator::VisitUnresolvedUsingValueDecl(
UnresolvedUsingValueDecl *D) {
return instantiateUnresolvedUsingDecl(D);
}
Decl *TemplateDeclInstantiator::VisitUnresolvedUsingIfExistsDecl(
UnresolvedUsingIfExistsDecl *D) {
llvm_unreachable("referring to unresolved decl out of UsingShadowDecl");
}
Decl *TemplateDeclInstantiator::VisitUsingPackDecl(UsingPackDecl *D) {
SmallVector<NamedDecl*, 8> Expansions;
for (auto *UD : D->expansions()) {
if (NamedDecl *NewUD =
SemaRef.FindInstantiatedDecl(D->getLocation(), UD, TemplateArgs))
Expansions.push_back(NewUD);
else
return nullptr;
}
auto *NewD = SemaRef.BuildUsingPackDecl(D, Expansions);
if (isDeclWithinFunction(D))
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewD);
return NewD;
}
Decl *TemplateDeclInstantiator::VisitOMPThreadPrivateDecl(
OMPThreadPrivateDecl *D) {
SmallVector<Expr *, 5> Vars;
for (auto *I : D->varlists()) {
Expr *Var = SemaRef.SubstExpr(I, TemplateArgs).get();
assert(isa<DeclRefExpr>(Var) && "threadprivate arg is not a DeclRefExpr");
Vars.push_back(Var);
}
OMPThreadPrivateDecl *TD =
SemaRef.OpenMP().CheckOMPThreadPrivateDecl(D->getLocation(), Vars);
TD->setAccess(AS_public);
Owner->addDecl(TD);
return TD;
}
Decl *TemplateDeclInstantiator::VisitOMPAllocateDecl(OMPAllocateDecl *D) {
SmallVector<Expr *, 5> Vars;
for (auto *I : D->varlists()) {
Expr *Var = SemaRef.SubstExpr(I, TemplateArgs).get();
assert(isa<DeclRefExpr>(Var) && "allocate arg is not a DeclRefExpr");
Vars.push_back(Var);
}
SmallVector<OMPClause *, 4> Clauses;
// Copy map clauses from the original mapper.
for (OMPClause *C : D->clauselists()) {
OMPClause *IC = nullptr;
if (auto *AC = dyn_cast<OMPAllocatorClause>(C)) {
ExprResult NewE = SemaRef.SubstExpr(AC->getAllocator(), TemplateArgs);
if (!NewE.isUsable())
continue;
IC = SemaRef.OpenMP().ActOnOpenMPAllocatorClause(
NewE.get(), AC->getBeginLoc(), AC->getLParenLoc(), AC->getEndLoc());
} else if (auto *AC = dyn_cast<OMPAlignClause>(C)) {
ExprResult NewE = SemaRef.SubstExpr(AC->getAlignment(), TemplateArgs);
if (!NewE.isUsable())
continue;
IC = SemaRef.OpenMP().ActOnOpenMPAlignClause(
NewE.get(), AC->getBeginLoc(), AC->getLParenLoc(), AC->getEndLoc());
// If align clause value ends up being invalid, this can end up null.
if (!IC)
continue;
}
Clauses.push_back(IC);
}
Sema::DeclGroupPtrTy Res = SemaRef.OpenMP().ActOnOpenMPAllocateDirective(
D->getLocation(), Vars, Clauses, Owner);
if (Res.get().isNull())
return nullptr;
return Res.get().getSingleDecl();
}
Decl *TemplateDeclInstantiator::VisitOMPRequiresDecl(OMPRequiresDecl *D) {
llvm_unreachable(
"Requires directive cannot be instantiated within a dependent context");
}
Decl *TemplateDeclInstantiator::VisitOMPDeclareReductionDecl(
OMPDeclareReductionDecl *D) {
// Instantiate type and check if it is allowed.
const bool RequiresInstantiation =
D->getType()->isDependentType() ||
D->getType()->isInstantiationDependentType() ||
D->getType()->containsUnexpandedParameterPack();
QualType SubstReductionType;
if (RequiresInstantiation) {
SubstReductionType = SemaRef.OpenMP().ActOnOpenMPDeclareReductionType(
D->getLocation(),
ParsedType::make(SemaRef.SubstType(
D->getType(), TemplateArgs, D->getLocation(), DeclarationName())));
} else {
SubstReductionType = D->getType();
}
if (SubstReductionType.isNull())
return nullptr;
Expr *Combiner = D->getCombiner();
Expr *Init = D->getInitializer();
bool IsCorrect = true;
// Create instantiated copy.
std::pair<QualType, SourceLocation> ReductionTypes[] = {
std::make_pair(SubstReductionType, D->getLocation())};
auto *PrevDeclInScope = D->getPrevDeclInScope();
if (PrevDeclInScope && !PrevDeclInScope->isInvalidDecl()) {
PrevDeclInScope = cast<OMPDeclareReductionDecl>(
SemaRef.CurrentInstantiationScope->findInstantiationOf(PrevDeclInScope)
->get<Decl *>());
}
auto DRD = SemaRef.OpenMP().ActOnOpenMPDeclareReductionDirectiveStart(
/*S=*/nullptr, Owner, D->getDeclName(), ReductionTypes, D->getAccess(),
PrevDeclInScope);
auto *NewDRD = cast<OMPDeclareReductionDecl>(DRD.get().getSingleDecl());
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewDRD);
Expr *SubstCombiner = nullptr;
Expr *SubstInitializer = nullptr;
// Combiners instantiation sequence.
if (Combiner) {
SemaRef.OpenMP().ActOnOpenMPDeclareReductionCombinerStart(
/*S=*/nullptr, NewDRD);
SemaRef.CurrentInstantiationScope->InstantiatedLocal(
cast<DeclRefExpr>(D->getCombinerIn())->getDecl(),
cast<DeclRefExpr>(NewDRD->getCombinerIn())->getDecl());
SemaRef.CurrentInstantiationScope->InstantiatedLocal(
cast<DeclRefExpr>(D->getCombinerOut())->getDecl(),
cast<DeclRefExpr>(NewDRD->getCombinerOut())->getDecl());
auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(Owner);
Sema::CXXThisScopeRAII ThisScope(SemaRef, ThisContext, Qualifiers(),
ThisContext);
SubstCombiner = SemaRef.SubstExpr(Combiner, TemplateArgs).get();
SemaRef.OpenMP().ActOnOpenMPDeclareReductionCombinerEnd(NewDRD,
SubstCombiner);
}
// Initializers instantiation sequence.
if (Init) {
VarDecl *OmpPrivParm =
SemaRef.OpenMP().ActOnOpenMPDeclareReductionInitializerStart(
/*S=*/nullptr, NewDRD);
SemaRef.CurrentInstantiationScope->InstantiatedLocal(
cast<DeclRefExpr>(D->getInitOrig())->getDecl(),
cast<DeclRefExpr>(NewDRD->getInitOrig())->getDecl());
SemaRef.CurrentInstantiationScope->InstantiatedLocal(
cast<DeclRefExpr>(D->getInitPriv())->getDecl(),
cast<DeclRefExpr>(NewDRD->getInitPriv())->getDecl());
if (D->getInitializerKind() == OMPDeclareReductionInitKind::Call) {
SubstInitializer = SemaRef.SubstExpr(Init, TemplateArgs).get();
} else {
auto *OldPrivParm =
cast<VarDecl>(cast<DeclRefExpr>(D->getInitPriv())->getDecl());
IsCorrect = IsCorrect && OldPrivParm->hasInit();
if (IsCorrect)
SemaRef.InstantiateVariableInitializer(OmpPrivParm, OldPrivParm,
TemplateArgs);
}
SemaRef.OpenMP().ActOnOpenMPDeclareReductionInitializerEnd(
NewDRD, SubstInitializer, OmpPrivParm);
}
IsCorrect = IsCorrect && SubstCombiner &&
(!Init ||
(D->getInitializerKind() == OMPDeclareReductionInitKind::Call &&
SubstInitializer) ||
(D->getInitializerKind() != OMPDeclareReductionInitKind::Call &&
!SubstInitializer));
(void)SemaRef.OpenMP().ActOnOpenMPDeclareReductionDirectiveEnd(
/*S=*/nullptr, DRD, IsCorrect && !D->isInvalidDecl());
return NewDRD;
}
Decl *
TemplateDeclInstantiator::VisitOMPDeclareMapperDecl(OMPDeclareMapperDecl *D) {
// Instantiate type and check if it is allowed.
const bool RequiresInstantiation =
D->getType()->isDependentType() ||
D->getType()->isInstantiationDependentType() ||
D->getType()->containsUnexpandedParameterPack();
QualType SubstMapperTy;
DeclarationName VN = D->getVarName();
if (RequiresInstantiation) {
SubstMapperTy = SemaRef.OpenMP().ActOnOpenMPDeclareMapperType(
D->getLocation(),
ParsedType::make(SemaRef.SubstType(D->getType(), TemplateArgs,
D->getLocation(), VN)));
} else {
SubstMapperTy = D->getType();
}
if (SubstMapperTy.isNull())
return nullptr;
// Create an instantiated copy of mapper.
auto *PrevDeclInScope = D->getPrevDeclInScope();
if (PrevDeclInScope && !PrevDeclInScope->isInvalidDecl()) {
PrevDeclInScope = cast<OMPDeclareMapperDecl>(
SemaRef.CurrentInstantiationScope->findInstantiationOf(PrevDeclInScope)
->get<Decl *>());
}
bool IsCorrect = true;
SmallVector<OMPClause *, 6> Clauses;
// Instantiate the mapper variable.
DeclarationNameInfo DirName;
SemaRef.OpenMP().StartOpenMPDSABlock(llvm::omp::OMPD_declare_mapper, DirName,
/*S=*/nullptr,
(*D->clauselist_begin())->getBeginLoc());
ExprResult MapperVarRef =
SemaRef.OpenMP().ActOnOpenMPDeclareMapperDirectiveVarDecl(
/*S=*/nullptr, SubstMapperTy, D->getLocation(), VN);
SemaRef.CurrentInstantiationScope->InstantiatedLocal(
cast<DeclRefExpr>(D->getMapperVarRef())->getDecl(),
cast<DeclRefExpr>(MapperVarRef.get())->getDecl());
auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(Owner);
Sema::CXXThisScopeRAII ThisScope(SemaRef, ThisContext, Qualifiers(),
ThisContext);
// Instantiate map clauses.
for (OMPClause *C : D->clauselists()) {
auto *OldC = cast<OMPMapClause>(C);
SmallVector<Expr *, 4> NewVars;
for (Expr *OE : OldC->varlists()) {
Expr *NE = SemaRef.SubstExpr(OE, TemplateArgs).get();
if (!NE) {
IsCorrect = false;
break;
}
NewVars.push_back(NE);
}
if (!IsCorrect)
break;
NestedNameSpecifierLoc NewQualifierLoc =
SemaRef.SubstNestedNameSpecifierLoc(OldC->getMapperQualifierLoc(),
TemplateArgs);
CXXScopeSpec SS;
SS.Adopt(NewQualifierLoc);
DeclarationNameInfo NewNameInfo =
SemaRef.SubstDeclarationNameInfo(OldC->getMapperIdInfo(), TemplateArgs);
OMPVarListLocTy Locs(OldC->getBeginLoc(), OldC->getLParenLoc(),
OldC->getEndLoc());
OMPClause *NewC = SemaRef.OpenMP().ActOnOpenMPMapClause(
OldC->getIteratorModifier(), OldC->getMapTypeModifiers(),
OldC->getMapTypeModifiersLoc(), SS, NewNameInfo, OldC->getMapType(),
OldC->isImplicitMapType(), OldC->getMapLoc(), OldC->getColonLoc(),
NewVars, Locs);
Clauses.push_back(NewC);
}
SemaRef.OpenMP().EndOpenMPDSABlock(nullptr);
if (!IsCorrect)
return nullptr;
Sema::DeclGroupPtrTy DG = SemaRef.OpenMP().ActOnOpenMPDeclareMapperDirective(
/*S=*/nullptr, Owner, D->getDeclName(), SubstMapperTy, D->getLocation(),
VN, D->getAccess(), MapperVarRef.get(), Clauses, PrevDeclInScope);
Decl *NewDMD = DG.get().getSingleDecl();
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewDMD);
return NewDMD;
}
Decl *TemplateDeclInstantiator::VisitOMPCapturedExprDecl(
OMPCapturedExprDecl * /*D*/) {
llvm_unreachable("Should not be met in templates");
}
Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D) {
return VisitFunctionDecl(D, nullptr);
}
Decl *
TemplateDeclInstantiator::VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *D) {
Decl *Inst = VisitFunctionDecl(D, nullptr);
if (Inst && !D->getDescribedFunctionTemplate())
Owner->addDecl(Inst);
return Inst;
}
Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D) {
return VisitCXXMethodDecl(D, nullptr);
}
Decl *TemplateDeclInstantiator::VisitRecordDecl(RecordDecl *D) {
llvm_unreachable("There are only CXXRecordDecls in C++");
}
Decl *
TemplateDeclInstantiator::VisitClassTemplateSpecializationDecl(
ClassTemplateSpecializationDecl *D) {
// As a MS extension, we permit class-scope explicit specialization
// of member class templates.
ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
assert(ClassTemplate->getDeclContext()->isRecord() &&
D->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
"can only instantiate an explicit specialization "
"for a member class template");
// Lookup the already-instantiated declaration in the instantiation
// of the class template.
ClassTemplateDecl *InstClassTemplate =
cast_or_null<ClassTemplateDecl>(SemaRef.FindInstantiatedDecl(
D->getLocation(), ClassTemplate, TemplateArgs));
if (!InstClassTemplate)
return nullptr;
// Substitute into the template arguments of the class template explicit
// specialization.
TemplateSpecializationTypeLoc Loc = D->getTypeAsWritten()->getTypeLoc().
castAs<TemplateSpecializationTypeLoc>();
TemplateArgumentListInfo InstTemplateArgs(Loc.getLAngleLoc(),
Loc.getRAngleLoc());
SmallVector<TemplateArgumentLoc, 4> ArgLocs;
for (unsigned I = 0; I != Loc.getNumArgs(); ++I)
ArgLocs.push_back(Loc.getArgLoc(I));
if (SemaRef.SubstTemplateArguments(ArgLocs, TemplateArgs, InstTemplateArgs))
return nullptr;
// Check that the template argument list is well-formed for this
// class template.
SmallVector<TemplateArgument, 4> SugaredConverted, CanonicalConverted;
if (SemaRef.CheckTemplateArgumentList(InstClassTemplate, D->getLocation(),
InstTemplateArgs, false,
SugaredConverted, CanonicalConverted,
/*UpdateArgsWithConversions=*/true))
return nullptr;
// Figure out where to insert this class template explicit specialization
// in the member template's set of class template explicit specializations.
void *InsertPos = nullptr;
ClassTemplateSpecializationDecl *PrevDecl =
InstClassTemplate->findSpecialization(CanonicalConverted, InsertPos);
// Check whether we've already seen a conflicting instantiation of this
// declaration (for instance, if there was a prior implicit instantiation).
bool Ignored;
if (PrevDecl &&
SemaRef.CheckSpecializationInstantiationRedecl(D->getLocation(),
D->getSpecializationKind(),
PrevDecl,
PrevDecl->getSpecializationKind(),
PrevDecl->getPointOfInstantiation(),
Ignored))
return nullptr;
// If PrevDecl was a definition and D is also a definition, diagnose.
// This happens in cases like:
//
// template<typename T, typename U>
// struct Outer {
// template<typename X> struct Inner;
// template<> struct Inner<T> {};
// template<> struct Inner<U> {};
// };
//
// Outer<int, int> outer; // error: the explicit specializations of Inner
// // have the same signature.
if (PrevDecl && PrevDecl->getDefinition() &&
D->isThisDeclarationADefinition()) {
SemaRef.Diag(D->getLocation(), diag::err_redefinition) << PrevDecl;
SemaRef.Diag(PrevDecl->getDefinition()->getLocation(),
diag::note_previous_definition);
return nullptr;
}
// Create the class template partial specialization declaration.
ClassTemplateSpecializationDecl *InstD =
ClassTemplateSpecializationDecl::Create(
SemaRef.Context, D->getTagKind(), Owner, D->getBeginLoc(),
D->getLocation(), InstClassTemplate, CanonicalConverted, PrevDecl);
// Add this partial specialization to the set of class template partial
// specializations.
if (!PrevDecl)
InstClassTemplate->AddSpecialization(InstD, InsertPos);
// Substitute the nested name specifier, if any.
if (SubstQualifier(D, InstD))
return nullptr;
// Build the canonical type that describes the converted template
// arguments of the class template explicit specialization.
QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
TemplateName(InstClassTemplate), CanonicalConverted,
SemaRef.Context.getRecordType(InstD));
// 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.
TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
TemplateName(InstClassTemplate), D->getLocation(), InstTemplateArgs,
CanonType);
InstD->setAccess(D->getAccess());
InstD->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
InstD->setSpecializationKind(D->getSpecializationKind());
InstD->setTypeAsWritten(WrittenTy);
InstD->setExternLoc(D->getExternLoc());
InstD->setTemplateKeywordLoc(D->getTemplateKeywordLoc());
Owner->addDecl(InstD);
// Instantiate the members of the class-scope explicit specialization eagerly.
// We don't have support for lazy instantiation of an explicit specialization
// yet, and MSVC eagerly instantiates in this case.
// FIXME: This is wrong in standard C++.
if (D->isThisDeclarationADefinition() &&
SemaRef.InstantiateClass(D->getLocation(), InstD, D, TemplateArgs,
TSK_ImplicitInstantiation,
/*Complain=*/true))
return nullptr;
return InstD;
}
Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
VarTemplateSpecializationDecl *D) {
TemplateArgumentListInfo VarTemplateArgsInfo;
VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
assert(VarTemplate &&
"A template specialization without specialized template?");
VarTemplateDecl *InstVarTemplate =
cast_or_null<VarTemplateDecl>(SemaRef.FindInstantiatedDecl(
D->getLocation(), VarTemplate, TemplateArgs));
if (!InstVarTemplate)
return nullptr;
// Substitute the current template arguments.
if (const ASTTemplateArgumentListInfo *TemplateArgsInfo =
D->getTemplateArgsInfo()) {
VarTemplateArgsInfo.setLAngleLoc(TemplateArgsInfo->getLAngleLoc());
VarTemplateArgsInfo.setRAngleLoc(TemplateArgsInfo->getRAngleLoc());
if (SemaRef.SubstTemplateArguments(TemplateArgsInfo->arguments(),
TemplateArgs, VarTemplateArgsInfo))
return nullptr;
}
// Check that the template argument list is well-formed for this template.
SmallVector<TemplateArgument, 4> SugaredConverted, CanonicalConverted;
if (SemaRef.CheckTemplateArgumentList(InstVarTemplate, D->getLocation(),
VarTemplateArgsInfo, false,
SugaredConverted, CanonicalConverted,
/*UpdateArgsWithConversions=*/true))
return nullptr;
// Check whether we've already seen a declaration of this specialization.
void *InsertPos = nullptr;
VarTemplateSpecializationDecl *PrevDecl =
InstVarTemplate->findSpecialization(CanonicalConverted, InsertPos);
// Check whether we've already seen a conflicting instantiation of this
// declaration (for instance, if there was a prior implicit instantiation).
bool Ignored;
if (PrevDecl && SemaRef.CheckSpecializationInstantiationRedecl(
D->getLocation(), D->getSpecializationKind(), PrevDecl,
PrevDecl->getSpecializationKind(),
PrevDecl->getPointOfInstantiation(), Ignored))
return nullptr;
return VisitVarTemplateSpecializationDecl(
InstVarTemplate, D, VarTemplateArgsInfo, CanonicalConverted, PrevDecl);
}
Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
VarTemplateDecl *VarTemplate, VarDecl *D,
const TemplateArgumentListInfo &TemplateArgsInfo,
ArrayRef<TemplateArgument> Converted,
VarTemplateSpecializationDecl *PrevDecl) {
// Do substitution on the type of the declaration
TypeSourceInfo *DI =
SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
D->getTypeSpecStartLoc(), D->getDeclName());
if (!DI)
return nullptr;
if (DI->getType()->isFunctionType()) {
SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
<< D->isStaticDataMember() << DI->getType();
return nullptr;
}
// Build the instantiated declaration
VarTemplateSpecializationDecl *Var = VarTemplateSpecializationDecl::Create(
SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
VarTemplate, DI->getType(), DI, D->getStorageClass(), Converted);
Var->setTemplateArgsInfo(TemplateArgsInfo);
if (!PrevDecl) {
void *InsertPos = nullptr;
VarTemplate->findSpecialization(Converted, InsertPos);
VarTemplate->AddSpecialization(Var, InsertPos);
}
if (SemaRef.getLangOpts().OpenCL)
SemaRef.deduceOpenCLAddressSpace(Var);
// Substitute the nested name specifier, if any.
if (SubstQualifier(D, Var))
return nullptr;
SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
StartingScope, false, PrevDecl);
return Var;
}
Decl *TemplateDeclInstantiator::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
llvm_unreachable("@defs is not supported in Objective-C++");
}
Decl *TemplateDeclInstantiator::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
// FIXME: We need to be able to instantiate FriendTemplateDecls.
unsigned DiagID = SemaRef.getDiagnostics().getCustomDiagID(
DiagnosticsEngine::Error,
"cannot instantiate %0 yet");
SemaRef.Diag(D->getLocation(), DiagID)
<< D->getDeclKindName();
return nullptr;
}
Decl *TemplateDeclInstantiator::VisitConceptDecl(ConceptDecl *D) {
llvm_unreachable("Concept definitions cannot reside inside a template");
}
Decl *TemplateDeclInstantiator::VisitImplicitConceptSpecializationDecl(
ImplicitConceptSpecializationDecl *D) {
llvm_unreachable("Concept specializations cannot reside inside a template");
}
Decl *
TemplateDeclInstantiator::VisitRequiresExprBodyDecl(RequiresExprBodyDecl *D) {
return RequiresExprBodyDecl::Create(SemaRef.Context, D->getDeclContext(),
D->getBeginLoc());
}
Decl *TemplateDeclInstantiator::VisitDecl(Decl *D) {
llvm_unreachable("Unexpected decl");
}
Decl *Sema::SubstDecl(Decl *D, DeclContext *Owner,
const MultiLevelTemplateArgumentList &TemplateArgs) {
TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
if (D->isInvalidDecl())
return nullptr;
Decl *SubstD;
runWithSufficientStackSpace(D->getLocation(), [&] {
SubstD = Instantiator.Visit(D);
});
return SubstD;
}
void TemplateDeclInstantiator::adjustForRewrite(RewriteKind RK,
FunctionDecl *Orig, QualType &T,
TypeSourceInfo *&TInfo,
DeclarationNameInfo &NameInfo) {
assert(RK == RewriteKind::RewriteSpaceshipAsEqualEqual);
// C++2a [class.compare.default]p3:
// the return type is replaced with bool
auto *FPT = T->castAs<FunctionProtoType>();
T = SemaRef.Context.getFunctionType(
SemaRef.Context.BoolTy, FPT->getParamTypes(), FPT->getExtProtoInfo());
// Update the return type in the source info too. The most straightforward
// way is to create new TypeSourceInfo for the new type. Use the location of
// the '= default' as the location of the new type.
//
// FIXME: Set the correct return type when we initially transform the type,
// rather than delaying it to now.
TypeSourceInfo *NewTInfo =
SemaRef.Context.getTrivialTypeSourceInfo(T, Orig->getEndLoc());
auto OldLoc = TInfo->getTypeLoc().getAsAdjusted<FunctionProtoTypeLoc>();
assert(OldLoc && "type of function is not a function type?");
auto NewLoc = NewTInfo->getTypeLoc().castAs<FunctionProtoTypeLoc>();
for (unsigned I = 0, N = OldLoc.getNumParams(); I != N; ++I)
NewLoc.setParam(I, OldLoc.getParam(I));
TInfo = NewTInfo;
// and the declarator-id is replaced with operator==
NameInfo.setName(
SemaRef.Context.DeclarationNames.getCXXOperatorName(OO_EqualEqual));
}
FunctionDecl *Sema::SubstSpaceshipAsEqualEqual(CXXRecordDecl *RD,
FunctionDecl *Spaceship) {
if (Spaceship->isInvalidDecl())
return nullptr;
// C++2a [class.compare.default]p3:
// an == operator function is declared implicitly [...] with the same
// access and function-definition and in the same class scope as the
// three-way comparison operator function
MultiLevelTemplateArgumentList NoTemplateArgs;
NoTemplateArgs.setKind(TemplateSubstitutionKind::Rewrite);
NoTemplateArgs.addOuterRetainedLevels(RD->getTemplateDepth());
TemplateDeclInstantiator Instantiator(*this, RD, NoTemplateArgs);
Decl *R;
if (auto *MD = dyn_cast<CXXMethodDecl>(Spaceship)) {
R = Instantiator.VisitCXXMethodDecl(
MD, /*TemplateParams=*/nullptr,
TemplateDeclInstantiator::RewriteKind::RewriteSpaceshipAsEqualEqual);
} else {
assert(Spaceship->getFriendObjectKind() &&
"defaulted spaceship is neither a member nor a friend");
R = Instantiator.VisitFunctionDecl(
Spaceship, /*TemplateParams=*/nullptr,
TemplateDeclInstantiator::RewriteKind::RewriteSpaceshipAsEqualEqual);
if (!R)
return nullptr;
FriendDecl *FD =
FriendDecl::Create(Context, RD, Spaceship->getLocation(),
cast<NamedDecl>(R), Spaceship->getBeginLoc());
FD->setAccess(AS_public);
RD->addDecl(FD);
}
return cast_or_null<FunctionDecl>(R);
}
/// Instantiates a nested template parameter list in the current
/// instantiation context.
///
/// \param L The parameter list to instantiate
///
/// \returns NULL if there was an error
TemplateParameterList *
TemplateDeclInstantiator::SubstTemplateParams(TemplateParameterList *L) {
// Get errors for all the parameters before bailing out.
bool Invalid = false;
unsigned N = L->size();
typedef SmallVector<NamedDecl *, 8> ParamVector;
ParamVector Params;
Params.reserve(N);
for (auto &P : *L) {
NamedDecl *D = cast_or_null<NamedDecl>(Visit(P));
Params.push_back(D);
Invalid = Invalid || !D || D->isInvalidDecl();
}
// Clean up if we had an error.
if (Invalid)
return nullptr;
Expr *InstRequiresClause = L->getRequiresClause();
TemplateParameterList *InstL
= TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
L->getLAngleLoc(), Params,
L->getRAngleLoc(), InstRequiresClause);
return InstL;
}
TemplateParameterList *
Sema::SubstTemplateParams(TemplateParameterList *Params, DeclContext *Owner,
const MultiLevelTemplateArgumentList &TemplateArgs,
bool EvaluateConstraints) {
TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
Instantiator.setEvaluateConstraints(EvaluateConstraints);
return Instantiator.SubstTemplateParams(Params);
}
/// Instantiate the declaration of a class template partial
/// specialization.
///
/// \param ClassTemplate the (instantiated) class template that is partially
// specialized by the instantiation of \p PartialSpec.
///
/// \param PartialSpec the (uninstantiated) class template partial
/// specialization that we are instantiating.
///
/// \returns The instantiated partial specialization, if successful; otherwise,
/// NULL to indicate an error.
ClassTemplatePartialSpecializationDecl *
TemplateDeclInstantiator::InstantiateClassTemplatePartialSpecialization(
ClassTemplateDecl *ClassTemplate,
ClassTemplatePartialSpecializationDecl *PartialSpec) {
// Create a local instantiation scope for this class template partial
// specialization, which will contain the instantiations of the template
// parameters.
LocalInstantiationScope Scope(SemaRef);
// Substitute into the template parameters of the class template partial
// specialization.
TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
// Substitute into the template arguments of the class template partial
// specialization.
const ASTTemplateArgumentListInfo *TemplArgInfo
= PartialSpec->getTemplateArgsAsWritten();
TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
TemplArgInfo->RAngleLoc);
if (SemaRef.SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
InstTemplateArgs))
return nullptr;
// Check that the template argument list is well-formed for this
// class template.
SmallVector<TemplateArgument, 4> SugaredConverted, CanonicalConverted;
if (SemaRef.CheckTemplateArgumentList(
ClassTemplate, PartialSpec->getLocation(), InstTemplateArgs,
/*PartialTemplateArgs=*/false, SugaredConverted, CanonicalConverted))
return nullptr;
// Check these arguments are valid for a template partial specialization.
if (SemaRef.CheckTemplatePartialSpecializationArgs(
PartialSpec->getLocation(), ClassTemplate, InstTemplateArgs.size(),
CanonicalConverted))
return nullptr;
// Figure out where to insert this class template partial specialization
// in the member template's set of class template partial specializations.
void *InsertPos = nullptr;
ClassTemplateSpecializationDecl *PrevDecl =
ClassTemplate->findPartialSpecialization(CanonicalConverted, InstParams,
InsertPos);
// Build the canonical type that describes the converted template
// arguments of the class template partial specialization.
QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
TemplateName(ClassTemplate), CanonicalConverted);
// 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.
TypeSourceInfo *WrittenTy
= SemaRef.Context.getTemplateSpecializationTypeInfo(
TemplateName(ClassTemplate),
PartialSpec->getLocation(),
InstTemplateArgs,
CanonType);
if (PrevDecl) {
// We've already seen a partial specialization with the same template
// parameters and template arguments. This can happen, for example, when
// substituting the outer template arguments ends up causing two
// class template partial specializations of a member class template
// to have identical forms, e.g.,
//
// template<typename T, typename U>
// struct Outer {
// template<typename X, typename Y> struct Inner;
// template<typename Y> struct Inner<T, Y>;
// template<typename Y> struct Inner<U, Y>;
// };
//
// Outer<int, int> outer; // error: the partial specializations of Inner
// // have the same signature.
SemaRef.Diag(PartialSpec->getLocation(), diag::err_partial_spec_redeclared)
<< WrittenTy->getType();
SemaRef.Diag(PrevDecl->getLocation(), diag::note_prev_partial_spec_here)
<< SemaRef.Context.getTypeDeclType(PrevDecl);
return nullptr;
}
// Create the class template partial specialization declaration.
ClassTemplatePartialSpecializationDecl *InstPartialSpec =
ClassTemplatePartialSpecializationDecl::Create(
SemaRef.Context, PartialSpec->getTagKind(), Owner,
PartialSpec->getBeginLoc(), PartialSpec->getLocation(), InstParams,
ClassTemplate, CanonicalConverted, InstTemplateArgs, CanonType,
nullptr);
// Substitute the nested name specifier, if any.
if (SubstQualifier(PartialSpec, InstPartialSpec))
return nullptr;
InstPartialSpec->setInstantiatedFromMember(PartialSpec);
InstPartialSpec->setTypeAsWritten(WrittenTy);
// Check the completed partial specialization.
SemaRef.CheckTemplatePartialSpecialization(InstPartialSpec);
// Add this partial specialization to the set of class template partial
// specializations.
ClassTemplate->AddPartialSpecialization(InstPartialSpec,
/*InsertPos=*/nullptr);
return InstPartialSpec;
}
/// Instantiate the declaration of a variable template partial
/// specialization.
///
/// \param VarTemplate the (instantiated) variable template that is partially
/// specialized by the instantiation of \p PartialSpec.
///
/// \param PartialSpec the (uninstantiated) variable template partial
/// specialization that we are instantiating.
///
/// \returns The instantiated partial specialization, if successful; otherwise,
/// NULL to indicate an error.
VarTemplatePartialSpecializationDecl *
TemplateDeclInstantiator::InstantiateVarTemplatePartialSpecialization(
VarTemplateDecl *VarTemplate,
VarTemplatePartialSpecializationDecl *PartialSpec) {
// Create a local instantiation scope for this variable template partial
// specialization, which will contain the instantiations of the template
// parameters.
LocalInstantiationScope Scope(SemaRef);
// Substitute into the template parameters of the variable template partial
// specialization.
TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
if (!InstParams)
return nullptr;
// Substitute into the template arguments of the variable template partial
// specialization.
const ASTTemplateArgumentListInfo *TemplArgInfo
= PartialSpec->getTemplateArgsAsWritten();
TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
TemplArgInfo->RAngleLoc);
if (SemaRef.SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
InstTemplateArgs))
return nullptr;
// Check that the template argument list is well-formed for this
// class template.
SmallVector<TemplateArgument, 4> SugaredConverted, CanonicalConverted;
if (SemaRef.CheckTemplateArgumentList(
VarTemplate, PartialSpec->getLocation(), InstTemplateArgs,
/*PartialTemplateArgs=*/false, SugaredConverted, CanonicalConverted))
return nullptr;
// Check these arguments are valid for a template partial specialization.
if (SemaRef.CheckTemplatePartialSpecializationArgs(
PartialSpec->getLocation(), VarTemplate, InstTemplateArgs.size(),
CanonicalConverted))
return nullptr;
// Figure out where to insert this variable template partial specialization
// in the member template's set of variable template partial specializations.
void *InsertPos = nullptr;
VarTemplateSpecializationDecl *PrevDecl =
VarTemplate->findPartialSpecialization(CanonicalConverted, InstParams,
InsertPos);
// Build the canonical type that describes the converted template
// arguments of the variable template partial specialization.
QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
TemplateName(VarTemplate), CanonicalConverted);
// Build the fully-sugared type for this variable 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.
TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
TemplateName(VarTemplate), PartialSpec->getLocation(), InstTemplateArgs,
CanonType);
if (PrevDecl) {
// We've already seen a partial specialization with the same template
// parameters and template arguments. This can happen, for example, when
// substituting the outer template arguments ends up causing two
// variable template partial specializations of a member variable template
// to have identical forms, e.g.,
//
// template<typename T, typename U>
// struct Outer {
// template<typename X, typename Y> pair<X,Y> p;
// template<typename Y> pair<T, Y> p;
// template<typename Y> pair<U, Y> p;
// };
//
// Outer<int, int> outer; // error: the partial specializations of Inner
// // have the same signature.
SemaRef.Diag(PartialSpec->getLocation(),
diag::err_var_partial_spec_redeclared)
<< WrittenTy->getType();
SemaRef.Diag(PrevDecl->getLocation(),
diag::note_var_prev_partial_spec_here);
return nullptr;
}
// Do substitution on the type of the declaration
TypeSourceInfo *DI = SemaRef.SubstType(
PartialSpec->getTypeSourceInfo(), TemplateArgs,
PartialSpec->getTypeSpecStartLoc(), PartialSpec->getDeclName());
if (!DI)
return nullptr;
if (DI->getType()->isFunctionType()) {
SemaRef.Diag(PartialSpec->getLocation(),
diag::err_variable_instantiates_to_function)
<< PartialSpec->isStaticDataMember() << DI->getType();
return nullptr;
}
// Create the variable template partial specialization declaration.
VarTemplatePartialSpecializationDecl *InstPartialSpec =
VarTemplatePartialSpecializationDecl::Create(
SemaRef.Context, Owner, PartialSpec->getInnerLocStart(),
PartialSpec->getLocation(), InstParams, VarTemplate, DI->getType(),
DI, PartialSpec->getStorageClass(), CanonicalConverted,
InstTemplateArgs);
// Substitute the nested name specifier, if any.
if (SubstQualifier(PartialSpec, InstPartialSpec))
return nullptr;
InstPartialSpec->setInstantiatedFromMember(PartialSpec);
InstPartialSpec->setTypeAsWritten(WrittenTy);
// Check the completed partial specialization.
SemaRef.CheckTemplatePartialSpecialization(InstPartialSpec);
// Add this partial specialization to the set of variable template partial
// specializations. The instantiation of the initializer is not necessary.
VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/nullptr);
SemaRef.BuildVariableInstantiation(InstPartialSpec, PartialSpec, TemplateArgs,
LateAttrs, Owner, StartingScope);
return InstPartialSpec;
}
TypeSourceInfo*
TemplateDeclInstantiator::SubstFunctionType(FunctionDecl *D,
SmallVectorImpl<ParmVarDecl *> &Params) {
TypeSourceInfo *OldTInfo = D->getTypeSourceInfo();
assert(OldTInfo && "substituting function without type source info");
assert(Params.empty() && "parameter vector is non-empty at start");
CXXRecordDecl *ThisContext = nullptr;
Qualifiers ThisTypeQuals;
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
ThisContext = cast<CXXRecordDecl>(Owner);
ThisTypeQuals = Method->getFunctionObjectParameterType().getQualifiers();
}
TypeSourceInfo *NewTInfo = SemaRef.SubstFunctionDeclType(
OldTInfo, TemplateArgs, D->getTypeSpecStartLoc(), D->getDeclName(),
ThisContext, ThisTypeQuals, EvaluateConstraints);
if (!NewTInfo)
return nullptr;
TypeLoc OldTL = OldTInfo->getTypeLoc().IgnoreParens();
if (FunctionProtoTypeLoc OldProtoLoc = OldTL.getAs<FunctionProtoTypeLoc>()) {
if (NewTInfo != OldTInfo) {
// Get parameters from the new type info.
TypeLoc NewTL = NewTInfo->getTypeLoc().IgnoreParens();
FunctionProtoTypeLoc NewProtoLoc = NewTL.castAs<FunctionProtoTypeLoc>();
unsigned NewIdx = 0;
for (unsigned OldIdx = 0, NumOldParams = OldProtoLoc.getNumParams();
OldIdx != NumOldParams; ++OldIdx) {
ParmVarDecl *OldParam = OldProtoLoc.getParam(OldIdx);
if (!OldParam)
return nullptr;
LocalInstantiationScope *Scope = SemaRef.CurrentInstantiationScope;
std::optional<unsigned> NumArgumentsInExpansion;
if (OldParam->isParameterPack())
NumArgumentsInExpansion =
SemaRef.getNumArgumentsInExpansion(OldParam->getType(),
TemplateArgs);
if (!NumArgumentsInExpansion) {
// Simple case: normal parameter, or a parameter pack that's
// instantiated to a (still-dependent) parameter pack.
ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
Params.push_back(NewParam);
Scope->InstantiatedLocal(OldParam, NewParam);
} else {
// Parameter pack expansion: make the instantiation an argument pack.
Scope->MakeInstantiatedLocalArgPack(OldParam);
for (unsigned I = 0; I != *NumArgumentsInExpansion; ++I) {
ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
Params.push_back(NewParam);
Scope->InstantiatedLocalPackArg(OldParam, NewParam);
}
}
}
} else {
// The function type itself was not dependent and therefore no
// substitution occurred. However, we still need to instantiate
// the function parameters themselves.
const FunctionProtoType *OldProto =
cast<FunctionProtoType>(OldProtoLoc.getType());
for (unsigned i = 0, i_end = OldProtoLoc.getNumParams(); i != i_end;
++i) {
ParmVarDecl *OldParam = OldProtoLoc.getParam(i);
if (!OldParam) {
Params.push_back(SemaRef.BuildParmVarDeclForTypedef(
D, D->getLocation(), OldProto->getParamType(i)));
continue;
}
ParmVarDecl *Parm =
cast_or_null<ParmVarDecl>(VisitParmVarDecl(OldParam));
if (!Parm)
return nullptr;
Params.push_back(Parm);
}
}
} else {
// If the type of this function, after ignoring parentheses, is not
// *directly* a function type, then we're instantiating a function that
// was declared via a typedef or with attributes, e.g.,
//
// typedef int functype(int, int);
// functype func;
// int __cdecl meth(int, int);
//
// In this case, we'll just go instantiate the ParmVarDecls that we
// synthesized in the method declaration.
SmallVector<QualType, 4> ParamTypes;
Sema::ExtParameterInfoBuilder ExtParamInfos;
if (SemaRef.SubstParmTypes(D->getLocation(), D->parameters(), nullptr,
TemplateArgs, ParamTypes, &Params,
ExtParamInfos))
return nullptr;
}
return NewTInfo;
}
/// Introduce the instantiated local variables into the local
/// instantiation scope.
void Sema::addInstantiatedLocalVarsToScope(FunctionDecl *Function,
const FunctionDecl *PatternDecl,
LocalInstantiationScope &Scope) {
LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(getFunctionScopes().back());
for (auto *decl : PatternDecl->decls()) {
if (!isa<VarDecl>(decl) || isa<ParmVarDecl>(decl))
continue;
VarDecl *VD = cast<VarDecl>(decl);
IdentifierInfo *II = VD->getIdentifier();
auto it = llvm::find_if(Function->decls(), [&](Decl *inst) {
VarDecl *InstVD = dyn_cast<VarDecl>(inst);
return InstVD && InstVD->isLocalVarDecl() &&
InstVD->getIdentifier() == II;
});
if (it == Function->decls().end())
continue;
Scope.InstantiatedLocal(VD, *it);
LSI->addCapture(cast<VarDecl>(*it), /*isBlock=*/false, /*isByref=*/false,
/*isNested=*/false, VD->getLocation(), SourceLocation(),
VD->getType(), /*Invalid=*/false);
}
}
/// Introduce the instantiated function parameters into the local
/// instantiation scope, and set the parameter names to those used
/// in the template.
bool Sema::addInstantiatedParametersToScope(
FunctionDecl *Function, const FunctionDecl *PatternDecl,
LocalInstantiationScope &Scope,
const MultiLevelTemplateArgumentList &TemplateArgs) {
unsigned FParamIdx = 0;
for (unsigned I = 0, N = PatternDecl->getNumParams(); I != N; ++I) {
const ParmVarDecl *PatternParam = PatternDecl->getParamDecl(I);
if (!PatternParam->isParameterPack()) {
// Simple case: not a parameter pack.
assert(FParamIdx < Function->getNumParams());
ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
FunctionParam->setDeclName(PatternParam->getDeclName());
// If the parameter's type is not dependent, update it to match the type
// in the pattern. They can differ in top-level cv-qualifiers, and we want
// the pattern's type here. If the type is dependent, they can't differ,
// per core issue 1668. Substitute into the type from the pattern, in case
// it's instantiation-dependent.
// FIXME: Updating the type to work around this is at best fragile.
if (!PatternDecl->getType()->isDependentType()) {
QualType T = SubstType(PatternParam->getType(), TemplateArgs,
FunctionParam->getLocation(),
FunctionParam->getDeclName());
if (T.isNull())
return true;
FunctionParam->setType(T);
}
Scope.InstantiatedLocal(PatternParam, FunctionParam);
++FParamIdx;
continue;
}
// Expand the parameter pack.
Scope.MakeInstantiatedLocalArgPack(PatternParam);
std::optional<unsigned> NumArgumentsInExpansion =
getNumArgumentsInExpansion(PatternParam->getType(), TemplateArgs);
if (NumArgumentsInExpansion) {
QualType PatternType =
PatternParam->getType()->castAs<PackExpansionType>()->getPattern();
for (unsigned Arg = 0; Arg < *NumArgumentsInExpansion; ++Arg) {
ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
FunctionParam->setDeclName(PatternParam->getDeclName());
if (!PatternDecl->getType()->isDependentType()) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, Arg);
QualType T =
SubstType(PatternType, TemplateArgs, FunctionParam->getLocation(),
FunctionParam->getDeclName());
if (T.isNull())
return true;
FunctionParam->setType(T);
}
Scope.InstantiatedLocalPackArg(PatternParam, FunctionParam);
++FParamIdx;
}
}
}
return false;
}
bool Sema::InstantiateDefaultArgument(SourceLocation CallLoc, FunctionDecl *FD,
ParmVarDecl *Param) {
assert(Param->hasUninstantiatedDefaultArg());
// Instantiate the expression.
//
// FIXME: Pass in a correct Pattern argument, otherwise
// getTemplateInstantiationArgs uses the lexical context of FD, e.g.
//
// template<typename T>
// struct A {
// static int FooImpl();
//
// template<typename Tp>
// // bug: default argument A<T>::FooImpl() is evaluated with 2-level
// // template argument list [[T], [Tp]], should be [[Tp]].
// friend A<Tp> Foo(int a);
// };
//
// template<typename T>
// A<T> Foo(int a = A<T>::FooImpl());
MultiLevelTemplateArgumentList TemplateArgs =
getTemplateInstantiationArgs(FD, FD->getLexicalDeclContext(),
/*Final=*/false, /*Innermost=*/std::nullopt,
/*RelativeToPrimary=*/true);
if (SubstDefaultArgument(CallLoc, Param, TemplateArgs, /*ForCallExpr*/ true))
return true;
if (ASTMutationListener *L = getASTMutationListener())
L->DefaultArgumentInstantiated(Param);
return false;
}
void Sema::InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
FunctionDecl *Decl) {
const FunctionProtoType *Proto = Decl->getType()->castAs<FunctionProtoType>();
if (Proto->getExceptionSpecType() != EST_Uninstantiated)
return;
InstantiatingTemplate Inst(*this, PointOfInstantiation, Decl,
InstantiatingTemplate::ExceptionSpecification());
if (Inst.isInvalid()) {
// We hit the instantiation depth limit. Clear the exception specification
// so that our callers don't have to cope with EST_Uninstantiated.
UpdateExceptionSpec(Decl, EST_None);
return;
}
if (Inst.isAlreadyInstantiating()) {
// This exception specification indirectly depends on itself. Reject.
// FIXME: Corresponding rule in the standard?
Diag(PointOfInstantiation, diag::err_exception_spec_cycle) << Decl;
UpdateExceptionSpec(Decl, EST_None);
return;
}
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
Sema::ContextRAII savedContext(*this, Decl);
LocalInstantiationScope Scope(*this);
MultiLevelTemplateArgumentList TemplateArgs =
getTemplateInstantiationArgs(Decl, Decl->getLexicalDeclContext(),
/*Final=*/false, /*Innermost=*/std::nullopt,
/*RelativeToPrimary*/ true);
// FIXME: We can't use getTemplateInstantiationPattern(false) in general
// here, because for a non-defining friend declaration in a class template,
// we don't store enough information to map back to the friend declaration in
// the template.
FunctionDecl *Template = Proto->getExceptionSpecTemplate();
if (addInstantiatedParametersToScope(Decl, Template, Scope, TemplateArgs)) {
UpdateExceptionSpec(Decl, EST_None);
return;
}
SubstExceptionSpec(Decl, Template->getType()->castAs<FunctionProtoType>(),
TemplateArgs);
}
/// Initializes the common fields of an instantiation function
/// declaration (New) from the corresponding fields of its template (Tmpl).
///
/// \returns true if there was an error
bool
TemplateDeclInstantiator::InitFunctionInstantiation(FunctionDecl *New,
FunctionDecl *Tmpl) {
New->setImplicit(Tmpl->isImplicit());
// Forward the mangling number from the template to the instantiated decl.
SemaRef.Context.setManglingNumber(New,
SemaRef.Context.getManglingNumber(Tmpl));
// If we are performing substituting explicitly-specified template arguments
// or deduced template arguments into a function template and we reach this
// point, we are now past the point where SFINAE applies and have committed
// to keeping the new function template specialization. We therefore
// convert the active template instantiation for the function template
// into a template instantiation for this specific function template
// specialization, which is not a SFINAE context, so that we diagnose any
// further errors in the declaration itself.
//
// FIXME: This is a hack.
typedef Sema::CodeSynthesisContext ActiveInstType;
ActiveInstType &ActiveInst = SemaRef.CodeSynthesisContexts.back();
if (ActiveInst.Kind == ActiveInstType::ExplicitTemplateArgumentSubstitution ||
ActiveInst.Kind == ActiveInstType::DeducedTemplateArgumentSubstitution) {
if (isa<FunctionTemplateDecl>(ActiveInst.Entity)) {
SemaRef.InstantiatingSpecializations.erase(
{ActiveInst.Entity->getCanonicalDecl(), ActiveInst.Kind});
atTemplateEnd(SemaRef.TemplateInstCallbacks, SemaRef, ActiveInst);
ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
ActiveInst.Entity = New;
atTemplateBegin(SemaRef.TemplateInstCallbacks, SemaRef, ActiveInst);
}
}
const FunctionProtoType *Proto = Tmpl->getType()->getAs<FunctionProtoType>();
assert(Proto && "Function template without prototype?");
if (Proto->hasExceptionSpec() || Proto->getNoReturnAttr()) {
FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
// DR1330: In C++11, defer instantiation of a non-trivial
// exception specification.
// DR1484: Local classes and their members are instantiated along with the
// containing function.
if (SemaRef.getLangOpts().CPlusPlus11 &&
EPI.ExceptionSpec.Type != EST_None &&
EPI.ExceptionSpec.Type != EST_DynamicNone &&
EPI.ExceptionSpec.Type != EST_BasicNoexcept &&
!Tmpl->isInLocalScopeForInstantiation()) {
FunctionDecl *ExceptionSpecTemplate = Tmpl;
if (EPI.ExceptionSpec.Type == EST_Uninstantiated)
ExceptionSpecTemplate = EPI.ExceptionSpec.SourceTemplate;
ExceptionSpecificationType NewEST = EST_Uninstantiated;
if (EPI.ExceptionSpec.Type == EST_Unevaluated)
NewEST = EST_Unevaluated;
// Mark the function has having an uninstantiated exception specification.
const FunctionProtoType *NewProto
= New->getType()->getAs<FunctionProtoType>();
assert(NewProto && "Template instantiation without function prototype?");
EPI = NewProto->getExtProtoInfo();
EPI.ExceptionSpec.Type = NewEST;
EPI.ExceptionSpec.SourceDecl = New;
EPI.ExceptionSpec.SourceTemplate = ExceptionSpecTemplate;
New->setType(SemaRef.Context.getFunctionType(
NewProto->getReturnType(), NewProto->getParamTypes(), EPI));
} else {
Sema::ContextRAII SwitchContext(SemaRef, New);
SemaRef.SubstExceptionSpec(New, Proto, TemplateArgs);
}
}
// Get the definition. Leaves the variable unchanged if undefined.
const FunctionDecl *Definition = Tmpl;
Tmpl->isDefined(Definition);
SemaRef.InstantiateAttrs(TemplateArgs, Definition, New,
LateAttrs, StartingScope);
return false;
}
/// Initializes common fields of an instantiated method
/// declaration (New) from the corresponding fields of its template
/// (Tmpl).
///
/// \returns true if there was an error
bool
TemplateDeclInstantiator::InitMethodInstantiation(CXXMethodDecl *New,
CXXMethodDecl *Tmpl) {
if (InitFunctionInstantiation(New, Tmpl))
return true;
if (isa<CXXDestructorDecl>(New) && SemaRef.getLangOpts().CPlusPlus11)
SemaRef.AdjustDestructorExceptionSpec(cast<CXXDestructorDecl>(New));
New->setAccess(Tmpl->getAccess());
if (Tmpl->isVirtualAsWritten())
New->setVirtualAsWritten(true);
// FIXME: New needs a pointer to Tmpl
return false;
}
bool TemplateDeclInstantiator::SubstDefaultedFunction(FunctionDecl *New,
FunctionDecl *Tmpl) {
// Transfer across any unqualified lookups.
if (auto *DFI = Tmpl->getDefalutedOrDeletedInfo()) {
SmallVector<DeclAccessPair, 32> Lookups;
Lookups.reserve(DFI->getUnqualifiedLookups().size());
bool AnyChanged = false;
for (DeclAccessPair DA : DFI->getUnqualifiedLookups()) {
NamedDecl *D = SemaRef.FindInstantiatedDecl(New->getLocation(),
DA.getDecl(), TemplateArgs);
if (!D)
return true;
AnyChanged |= (D != DA.getDecl());
Lookups.push_back(DeclAccessPair::make(D, DA.getAccess()));
}
// It's unlikely that substitution will change any declarations. Don't
// store an unnecessary copy in that case.
New->setDefaultedOrDeletedInfo(
AnyChanged ? FunctionDecl::DefaultedOrDeletedFunctionInfo::Create(
SemaRef.Context, Lookups)
: DFI);
}
SemaRef.SetDeclDefaulted(New, Tmpl->getLocation());
return false;
}
/// Instantiate (or find existing instantiation of) a function template with a
/// given set of template arguments.
///
/// Usually this should not be used, and template argument deduction should be
/// used in its place.
FunctionDecl *Sema::InstantiateFunctionDeclaration(
FunctionTemplateDecl *FTD, const TemplateArgumentList *Args,
SourceLocation Loc, CodeSynthesisContext::SynthesisKind CSC) {
FunctionDecl *FD = FTD->getTemplatedDecl();
sema::TemplateDeductionInfo Info(Loc);
InstantiatingTemplate Inst(*this, Loc, FTD, Args->asArray(), CSC, Info);
if (Inst.isInvalid())
return nullptr;
ContextRAII SavedContext(*this, FD);
MultiLevelTemplateArgumentList MArgs(FTD, Args->asArray(),
/*Final=*/false);
return cast_or_null<FunctionDecl>(SubstDecl(FD, FD->getParent(), MArgs));
}
/// Instantiate the definition of the given function from its
/// template.
///
/// \param PointOfInstantiation the point at which the instantiation was
/// required. Note that this is not precisely a "point of instantiation"
/// for the function, but it's close.
///
/// \param Function the already-instantiated declaration of a
/// function template specialization or member function of a class template
/// specialization.
///
/// \param Recursive if true, recursively instantiates any functions that
/// are required by this instantiation.
///
/// \param DefinitionRequired if true, then we are performing an explicit
/// instantiation where the body of the function is required. Complain if
/// there is no such body.
void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
FunctionDecl *Function,
bool Recursive,
bool DefinitionRequired,
bool AtEndOfTU) {
if (Function->isInvalidDecl() || isa<CXXDeductionGuideDecl>(Function))
return;
// Never instantiate an explicit specialization except if it is a class scope
// explicit specialization.
TemplateSpecializationKind TSK =
Function->getTemplateSpecializationKindForInstantiation();
if (TSK == TSK_ExplicitSpecialization)
return;
// Never implicitly instantiate a builtin; we don't actually need a function
// body.
if (Function->getBuiltinID() && TSK == TSK_ImplicitInstantiation &&
!DefinitionRequired)
return;
// Don't instantiate a definition if we already have one.
const FunctionDecl *ExistingDefn = nullptr;
if (Function->isDefined(ExistingDefn,
/*CheckForPendingFriendDefinition=*/true)) {
if (ExistingDefn->isThisDeclarationADefinition())
return;
// If we're asked to instantiate a function whose body comes from an
// instantiated friend declaration, attach the instantiated body to the
// corresponding declaration of the function.
assert(ExistingDefn->isThisDeclarationInstantiatedFromAFriendDefinition());
Function = const_cast<FunctionDecl*>(ExistingDefn);
}
// Find the function body that we'll be substituting.
const FunctionDecl *PatternDecl = Function->getTemplateInstantiationPattern();
assert(PatternDecl && "instantiating a non-template");
const FunctionDecl *PatternDef = PatternDecl->getDefinition();
Stmt *Pattern = nullptr;
if (PatternDef) {
Pattern = PatternDef->getBody(PatternDef);
PatternDecl = PatternDef;
if (PatternDef->willHaveBody())
PatternDef = nullptr;
}
// FIXME: We need to track the instantiation stack in order to know which
// definitions should be visible within this instantiation.
if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Function,
Function->getInstantiatedFromMemberFunction(),
PatternDecl, PatternDef, TSK,
/*Complain*/DefinitionRequired)) {
if (DefinitionRequired)
Function->setInvalidDecl();
else if (TSK == TSK_ExplicitInstantiationDefinition ||
(Function->isConstexpr() && !Recursive)) {
// Try again at the end of the translation unit (at which point a
// definition will be required).
assert(!Recursive);
Function->setInstantiationIsPending(true);
PendingInstantiations.push_back(
std::make_pair(Function, PointOfInstantiation));
} else if (TSK == TSK_ImplicitInstantiation) {
if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
!getSourceManager().isInSystemHeader(PatternDecl->getBeginLoc())) {
Diag(PointOfInstantiation, diag::warn_func_template_missing)
<< Function;
Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
if (getLangOpts().CPlusPlus11)
Diag(PointOfInstantiation, diag::note_inst_declaration_hint)
<< Function;
}
}
return;
}
// Postpone late parsed template instantiations.
if (PatternDecl->isLateTemplateParsed() &&
!LateTemplateParser) {
Function->setInstantiationIsPending(true);
LateParsedInstantiations.push_back(
std::make_pair(Function, PointOfInstantiation));
return;
}
llvm::TimeTraceScope TimeScope("InstantiateFunction", [&]() {
std::string Name;
llvm::raw_string_ostream OS(Name);
Function->getNameForDiagnostic(OS, getPrintingPolicy(),
/*Qualified=*/true);
return Name;
});
// If we're performing recursive template instantiation, create our own
// queue of pending implicit instantiations that we will instantiate later,
// while we're still within our own instantiation context.
// This has to happen before LateTemplateParser below is called, so that
// it marks vtables used in late parsed templates as used.
GlobalEagerInstantiationScope GlobalInstantiations(*this,
/*Enabled=*/Recursive);
LocalEagerInstantiationScope LocalInstantiations(*this);
// Call the LateTemplateParser callback if there is a need to late parse
// a templated function definition.
if (!Pattern && PatternDecl->isLateTemplateParsed() &&
LateTemplateParser) {
// FIXME: Optimize to allow individual templates to be deserialized.
if (PatternDecl->isFromASTFile())
ExternalSource->ReadLateParsedTemplates(LateParsedTemplateMap);
auto LPTIter = LateParsedTemplateMap.find(PatternDecl);
assert(LPTIter != LateParsedTemplateMap.end() &&
"missing LateParsedTemplate");
LateTemplateParser(OpaqueParser, *LPTIter->second);
Pattern = PatternDecl->getBody(PatternDecl);
updateAttrsForLateParsedTemplate(PatternDecl, Function);
}
// Note, we should never try to instantiate a deleted function template.
assert((Pattern || PatternDecl->isDefaulted() ||
PatternDecl->hasSkippedBody()) &&
"unexpected kind of function template definition");
// C++1y [temp.explicit]p10:
// Except for inline functions, declarations with types deduced from their
// initializer or return value, and class template specializations, other
// explicit instantiation declarations have the effect of suppressing the
// implicit instantiation of the entity to which they refer.
if (TSK == TSK_ExplicitInstantiationDeclaration &&
!PatternDecl->isInlined() &&
!PatternDecl->getReturnType()->getContainedAutoType())
return;
if (PatternDecl->isInlined()) {
// Function, and all later redeclarations of it (from imported modules,
// for instance), are now implicitly inline.
for (auto *D = Function->getMostRecentDecl(); /**/;
D = D->getPreviousDecl()) {
D->setImplicitlyInline();
if (D == Function)
break;
}
}
InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
return;
PrettyDeclStackTraceEntry CrashInfo(Context, Function, SourceLocation(),
"instantiating function definition");
// The instantiation is visible here, even if it was first declared in an
// unimported module.
Function->setVisibleDespiteOwningModule();
// Copy the source locations from the pattern.
Function->setLocation(PatternDecl->getLocation());
Function->setInnerLocStart(PatternDecl->getInnerLocStart());
Function->setRangeEnd(PatternDecl->getEndLoc());
EnterExpressionEvaluationContext EvalContext(
*this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
// Introduce a new scope where local variable instantiations will be
// recorded, unless we're actually a member function within a local
// class, in which case we need to merge our results with the parent
// scope (of the enclosing function). The exception is instantiating
// a function template specialization, since the template to be
// instantiated already has references to locals properly substituted.
bool MergeWithParentScope = false;
if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Function->getDeclContext()))
MergeWithParentScope =
Rec->isLocalClass() && !Function->isFunctionTemplateSpecialization();
LocalInstantiationScope Scope(*this, MergeWithParentScope);
auto RebuildTypeSourceInfoForDefaultSpecialMembers = [&]() {
// Special members might get their TypeSourceInfo set up w.r.t the
// PatternDecl context, in which case parameters could still be pointing
// back to the original class, make sure arguments are bound to the
// instantiated record instead.
assert(PatternDecl->isDefaulted() &&
"Special member needs to be defaulted");
auto PatternSM = getDefaultedFunctionKind(PatternDecl).asSpecialMember();
if (!(PatternSM == CXXSpecialMemberKind::CopyConstructor ||
PatternSM == CXXSpecialMemberKind::CopyAssignment ||
PatternSM == CXXSpecialMemberKind::MoveConstructor ||
PatternSM == CXXSpecialMemberKind::MoveAssignment))
return;
auto *NewRec = dyn_cast<CXXRecordDecl>(Function->getDeclContext());
const auto *PatternRec =
dyn_cast<CXXRecordDecl>(PatternDecl->getDeclContext());
if (!NewRec || !PatternRec)
return;
if (!PatternRec->isLambda())
return;
struct SpecialMemberTypeInfoRebuilder
: TreeTransform<SpecialMemberTypeInfoRebuilder> {
using Base = TreeTransform<SpecialMemberTypeInfoRebuilder>;
const CXXRecordDecl *OldDecl;
CXXRecordDecl *NewDecl;
SpecialMemberTypeInfoRebuilder(Sema &SemaRef, const CXXRecordDecl *O,
CXXRecordDecl *N)
: TreeTransform(SemaRef), OldDecl(O), NewDecl(N) {}
bool TransformExceptionSpec(SourceLocation Loc,
FunctionProtoType::ExceptionSpecInfo &ESI,
SmallVectorImpl<QualType> &Exceptions,
bool &Changed) {
return false;
}
QualType TransformRecordType(TypeLocBuilder &TLB, RecordTypeLoc TL) {
const RecordType *T = TL.getTypePtr();
RecordDecl *Record = cast_or_null<RecordDecl>(
getDerived().TransformDecl(TL.getNameLoc(), T->getDecl()));
if (Record != OldDecl)
return Base::TransformRecordType(TLB, TL);
QualType Result = getDerived().RebuildRecordType(NewDecl);
if (Result.isNull())
return QualType();
RecordTypeLoc NewTL = TLB.push<RecordTypeLoc>(Result);
NewTL.setNameLoc(TL.getNameLoc());
return Result;
}
} IR{*this, PatternRec, NewRec};
TypeSourceInfo *NewSI = IR.TransformType(Function->getTypeSourceInfo());
assert(NewSI && "Type Transform failed?");
Function->setType(NewSI->getType());
Function->setTypeSourceInfo(NewSI);
ParmVarDecl *Parm = Function->getParamDecl(0);
TypeSourceInfo *NewParmSI = IR.TransformType(Parm->getTypeSourceInfo());
Parm->setType(NewParmSI->getType());
Parm->setTypeSourceInfo(NewParmSI);
};
if (PatternDecl->isDefaulted()) {
RebuildTypeSourceInfoForDefaultSpecialMembers();
SetDeclDefaulted(Function, PatternDecl->getLocation());
} else {
MultiLevelTemplateArgumentList TemplateArgs = getTemplateInstantiationArgs(
Function, Function->getLexicalDeclContext(), /*Final=*/false,
/*Innermost=*/std::nullopt, false, PatternDecl);
// Substitute into the qualifier; we can get a substitution failure here
// through evil use of alias templates.
// FIXME: Is CurContext correct for this? Should we go to the (instantiation
// of the) lexical context of the pattern?
SubstQualifier(*this, PatternDecl, Function, TemplateArgs);
ActOnStartOfFunctionDef(nullptr, Function);
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
Sema::ContextRAII savedContext(*this, Function);
FPFeaturesStateRAII SavedFPFeatures(*this);
CurFPFeatures = FPOptions(getLangOpts());
FpPragmaStack.CurrentValue = FPOptionsOverride();
if (addInstantiatedParametersToScope(Function, PatternDecl, Scope,
TemplateArgs))
return;
StmtResult Body;
if (PatternDecl->hasSkippedBody()) {
ActOnSkippedFunctionBody(Function);
Body = nullptr;
} else {
if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Function)) {
// If this is a constructor, instantiate the member initializers.
InstantiateMemInitializers(Ctor, cast<CXXConstructorDecl>(PatternDecl),
TemplateArgs);
// If this is an MS ABI dllexport default constructor, instantiate any
// default arguments.
if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
Ctor->isDefaultConstructor()) {
InstantiateDefaultCtorDefaultArgs(Ctor);
}
}
// Instantiate the function body.
Body = SubstStmt(Pattern, TemplateArgs);
if (Body.isInvalid())
Function->setInvalidDecl();
}
// FIXME: finishing the function body while in an expression evaluation
// context seems wrong. Investigate more.
ActOnFinishFunctionBody(Function, Body.get(), /*IsInstantiation=*/true);
PerformDependentDiagnostics(PatternDecl, TemplateArgs);
if (auto *Listener = getASTMutationListener())
Listener->FunctionDefinitionInstantiated(Function);
savedContext.pop();
}
DeclGroupRef DG(Function);
Consumer.HandleTopLevelDecl(DG);
// This class may have local implicit instantiations that need to be
// instantiation within this scope.
LocalInstantiations.perform();
Scope.Exit();
GlobalInstantiations.perform();
}
VarTemplateSpecializationDecl *Sema::BuildVarTemplateInstantiation(
VarTemplateDecl *VarTemplate, VarDecl *FromVar,
const TemplateArgumentList *PartialSpecArgs,
const TemplateArgumentListInfo &TemplateArgsInfo,
SmallVectorImpl<TemplateArgument> &Converted,
SourceLocation PointOfInstantiation, LateInstantiatedAttrVec *LateAttrs,
LocalInstantiationScope *StartingScope) {
if (FromVar->isInvalidDecl())
return nullptr;
InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
if (Inst.isInvalid())
return nullptr;
// Instantiate the first declaration of the variable template: for a partial
// specialization of a static data member template, the first declaration may
// or may not be the declaration in the class; if it's in the class, we want
// to instantiate a member in the class (a declaration), and if it's outside,
// we want to instantiate a definition.
//
// If we're instantiating an explicitly-specialized member template or member
// partial specialization, don't do this. The member specialization completely
// replaces the original declaration in this case.
bool IsMemberSpec = false;
MultiLevelTemplateArgumentList MultiLevelList;
if (auto *PartialSpec =
dyn_cast<VarTemplatePartialSpecializationDecl>(FromVar)) {
assert(PartialSpecArgs);
IsMemberSpec = PartialSpec->isMemberSpecialization();
MultiLevelList.addOuterTemplateArguments(
PartialSpec, PartialSpecArgs->asArray(), /*Final=*/false);
} else {
assert(VarTemplate == FromVar->getDescribedVarTemplate());
IsMemberSpec = VarTemplate->isMemberSpecialization();
MultiLevelList.addOuterTemplateArguments(VarTemplate, Converted,
/*Final=*/false);
}
if (!IsMemberSpec)
FromVar = FromVar->getFirstDecl();
TemplateDeclInstantiator Instantiator(*this, FromVar->getDeclContext(),
MultiLevelList);
// TODO: Set LateAttrs and StartingScope ...
return cast_or_null<VarTemplateSpecializationDecl>(
Instantiator.VisitVarTemplateSpecializationDecl(
VarTemplate, FromVar, TemplateArgsInfo, Converted));
}
/// Instantiates a variable template specialization by completing it
/// with appropriate type information and initializer.
VarTemplateSpecializationDecl *Sema::CompleteVarTemplateSpecializationDecl(
VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
const MultiLevelTemplateArgumentList &TemplateArgs) {
assert(PatternDecl->isThisDeclarationADefinition() &&
"don't have a definition to instantiate from");
// Do substitution on the type of the declaration
TypeSourceInfo *DI =
SubstType(PatternDecl->getTypeSourceInfo(), TemplateArgs,
PatternDecl->getTypeSpecStartLoc(), PatternDecl->getDeclName());
if (!DI)
return nullptr;
// Update the type of this variable template specialization.
VarSpec->setType(DI->getType());
// Convert the declaration into a definition now.
VarSpec->setCompleteDefinition();
// Instantiate the initializer.
InstantiateVariableInitializer(VarSpec, PatternDecl, TemplateArgs);
if (getLangOpts().OpenCL)
deduceOpenCLAddressSpace(VarSpec);
return VarSpec;
}
/// BuildVariableInstantiation - Used after a new variable has been created.
/// Sets basic variable data and decides whether to postpone the
/// variable instantiation.
void Sema::BuildVariableInstantiation(
VarDecl *NewVar, VarDecl *OldVar,
const MultiLevelTemplateArgumentList &TemplateArgs,
LateInstantiatedAttrVec *LateAttrs, DeclContext *Owner,
LocalInstantiationScope *StartingScope,
bool InstantiatingVarTemplate,
VarTemplateSpecializationDecl *PrevDeclForVarTemplateSpecialization) {
// Instantiating a partial specialization to produce a partial
// specialization.
bool InstantiatingVarTemplatePartialSpec =
isa<VarTemplatePartialSpecializationDecl>(OldVar) &&
isa<VarTemplatePartialSpecializationDecl>(NewVar);
// Instantiating from a variable template (or partial specialization) to
// produce a variable template specialization.
bool InstantiatingSpecFromTemplate =
isa<VarTemplateSpecializationDecl>(NewVar) &&
(OldVar->getDescribedVarTemplate() ||
isa<VarTemplatePartialSpecializationDecl>(OldVar));
// If we are instantiating a local extern declaration, the
// instantiation belongs lexically to the containing function.
// If we are instantiating a static data member defined
// out-of-line, the instantiation will have the same lexical
// context (which will be a namespace scope) as the template.
if (OldVar->isLocalExternDecl()) {
NewVar->setLocalExternDecl();
NewVar->setLexicalDeclContext(Owner);
} else if (OldVar->isOutOfLine())
NewVar->setLexicalDeclContext(OldVar->getLexicalDeclContext());
NewVar->setTSCSpec(OldVar->getTSCSpec());
NewVar->setInitStyle(OldVar->getInitStyle());
NewVar->setCXXForRangeDecl(OldVar->isCXXForRangeDecl());
NewVar->setObjCForDecl(OldVar->isObjCForDecl());
NewVar->setConstexpr(OldVar->isConstexpr());
NewVar->setInitCapture(OldVar->isInitCapture());
NewVar->setPreviousDeclInSameBlockScope(
OldVar->isPreviousDeclInSameBlockScope());
NewVar->setAccess(OldVar->getAccess());
if (!OldVar->isStaticDataMember()) {
if (OldVar->isUsed(false))
NewVar->setIsUsed();
NewVar->setReferenced(OldVar->isReferenced());
}
InstantiateAttrs(TemplateArgs, OldVar, NewVar, LateAttrs, StartingScope);
LookupResult Previous(
*this, NewVar->getDeclName(), NewVar->getLocation(),
NewVar->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
: Sema::LookupOrdinaryName,
NewVar->isLocalExternDecl() ? RedeclarationKind::ForExternalRedeclaration
: forRedeclarationInCurContext());
if (NewVar->isLocalExternDecl() && OldVar->getPreviousDecl() &&
(!OldVar->getPreviousDecl()->getDeclContext()->isDependentContext() ||
OldVar->getPreviousDecl()->getDeclContext()==OldVar->getDeclContext())) {
// We have a previous declaration. Use that one, so we merge with the
// right type.
if (NamedDecl *NewPrev = FindInstantiatedDecl(
NewVar->getLocation(), OldVar->getPreviousDecl(), TemplateArgs))
Previous.addDecl(NewPrev);
} else if (!isa<VarTemplateSpecializationDecl>(NewVar) &&
OldVar->hasLinkage()) {
LookupQualifiedName(Previous, NewVar->getDeclContext(), false);
} else if (PrevDeclForVarTemplateSpecialization) {
Previous.addDecl(PrevDeclForVarTemplateSpecialization);
}
CheckVariableDeclaration(NewVar, Previous);
if (!InstantiatingVarTemplate) {
NewVar->getLexicalDeclContext()->addHiddenDecl(NewVar);
if (!NewVar->isLocalExternDecl() || !NewVar->getPreviousDecl())
NewVar->getDeclContext()->makeDeclVisibleInContext(NewVar);
}
if (!OldVar->isOutOfLine()) {
if (NewVar->getDeclContext()->isFunctionOrMethod())
CurrentInstantiationScope->InstantiatedLocal(OldVar, NewVar);
}
// Link instantiations of static data members back to the template from
// which they were instantiated.
//
// Don't do this when instantiating a template (we link the template itself
// back in that case) nor when instantiating a static data member template
// (that's not a member specialization).
if (NewVar->isStaticDataMember() && !InstantiatingVarTemplate &&
!InstantiatingSpecFromTemplate)
NewVar->setInstantiationOfStaticDataMember(OldVar,
TSK_ImplicitInstantiation);
// If the pattern is an (in-class) explicit specialization, then the result
// is also an explicit specialization.
if (VarTemplateSpecializationDecl *OldVTSD =
dyn_cast<VarTemplateSpecializationDecl>(OldVar)) {
if (OldVTSD->getSpecializationKind() == TSK_ExplicitSpecialization &&
!isa<VarTemplatePartialSpecializationDecl>(OldVTSD))
cast<VarTemplateSpecializationDecl>(NewVar)->setSpecializationKind(
TSK_ExplicitSpecialization);
}
// Forward the mangling number from the template to the instantiated decl.
Context.setManglingNumber(NewVar, Context.getManglingNumber(OldVar));
Context.setStaticLocalNumber(NewVar, Context.getStaticLocalNumber(OldVar));
// Figure out whether to eagerly instantiate the initializer.
if (InstantiatingVarTemplate || InstantiatingVarTemplatePartialSpec) {
// We're producing a template. Don't instantiate the initializer yet.
} else if (NewVar->getType()->isUndeducedType()) {
// We need the type to complete the declaration of the variable.
InstantiateVariableInitializer(NewVar, OldVar, TemplateArgs);
} else if (InstantiatingSpecFromTemplate ||
(OldVar->isInline() && OldVar->isThisDeclarationADefinition() &&
!NewVar->isThisDeclarationADefinition())) {
// Delay instantiation of the initializer for variable template
// specializations or inline static data members until a definition of the
// variable is needed.
} else {
InstantiateVariableInitializer(NewVar, OldVar, TemplateArgs);
}
// Diagnose unused local variables with dependent types, where the diagnostic
// will have been deferred.
if (!NewVar->isInvalidDecl() &&
NewVar->getDeclContext()->isFunctionOrMethod() &&
OldVar->getType()->isDependentType())
DiagnoseUnusedDecl(NewVar);
}
/// Instantiate the initializer of a variable.
void Sema::InstantiateVariableInitializer(
VarDecl *Var, VarDecl *OldVar,
const MultiLevelTemplateArgumentList &TemplateArgs) {
if (ASTMutationListener *L = getASTContext().getASTMutationListener())
L->VariableDefinitionInstantiated(Var);
// We propagate the 'inline' flag with the initializer, because it
// would otherwise imply that the variable is a definition for a
// non-static data member.
if (OldVar->isInlineSpecified())
Var->setInlineSpecified();
else if (OldVar->isInline())
Var->setImplicitlyInline();
if (OldVar->getInit()) {
EnterExpressionEvaluationContext Evaluated(
*this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated, Var);
keepInLifetimeExtendingContext();
// Instantiate the initializer.
ExprResult Init;
{
ContextRAII SwitchContext(*this, Var->getDeclContext());
Init = SubstInitializer(OldVar->getInit(), TemplateArgs,
OldVar->getInitStyle() == VarDecl::CallInit);
}
if (!Init.isInvalid()) {
Expr *InitExpr = Init.get();
if (Var->hasAttr<DLLImportAttr>() &&
(!InitExpr ||
!InitExpr->isConstantInitializer(getASTContext(), false))) {
// Do not dynamically initialize dllimport variables.
} else if (InitExpr) {
bool DirectInit = OldVar->isDirectInit();
AddInitializerToDecl(Var, InitExpr, DirectInit);
} else
ActOnUninitializedDecl(Var);
} else {
// FIXME: Not too happy about invalidating the declaration
// because of a bogus initializer.
Var->setInvalidDecl();
}
} else {
// `inline` variables are a definition and declaration all in one; we won't
// pick up an initializer from anywhere else.
if (Var->isStaticDataMember() && !Var->isInline()) {
if (!Var->isOutOfLine())
return;
// If the declaration inside the class had an initializer, don't add
// another one to the out-of-line definition.
if (OldVar->getFirstDecl()->hasInit())
return;
}
// We'll add an initializer to a for-range declaration later.
if (Var->isCXXForRangeDecl() || Var->isObjCForDecl())
return;
ActOnUninitializedDecl(Var);
}
if (getLangOpts().CUDA)
CUDA().checkAllowedInitializer(Var);
}
/// Instantiate the definition of the given variable from its
/// template.
///
/// \param PointOfInstantiation the point at which the instantiation was
/// required. Note that this is not precisely a "point of instantiation"
/// for the variable, but it's close.
///
/// \param Var the already-instantiated declaration of a templated variable.
///
/// \param Recursive if true, recursively instantiates any functions that
/// are required by this instantiation.
///
/// \param DefinitionRequired if true, then we are performing an explicit
/// instantiation where a definition of the variable is required. Complain
/// if there is no such definition.
void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
VarDecl *Var, bool Recursive,
bool DefinitionRequired, bool AtEndOfTU) {
if (Var->isInvalidDecl())
return;
// Never instantiate an explicitly-specialized entity.
TemplateSpecializationKind TSK =
Var->getTemplateSpecializationKindForInstantiation();
if (TSK == TSK_ExplicitSpecialization)
return;
// Find the pattern and the arguments to substitute into it.
VarDecl *PatternDecl = Var->getTemplateInstantiationPattern();
assert(PatternDecl && "no pattern for templated variable");
MultiLevelTemplateArgumentList TemplateArgs =
getTemplateInstantiationArgs(Var);
VarTemplateSpecializationDecl *VarSpec =
dyn_cast<VarTemplateSpecializationDecl>(Var);
if (VarSpec) {
// If this is a static data member template, there might be an
// uninstantiated initializer on the declaration. If so, instantiate
// it now.
//
// FIXME: This largely duplicates what we would do below. The difference
// is that along this path we may instantiate an initializer from an
// in-class declaration of the template and instantiate the definition
// from a separate out-of-class definition.
if (PatternDecl->isStaticDataMember() &&
(PatternDecl = PatternDecl->getFirstDecl())->hasInit() &&
!Var->hasInit()) {
// FIXME: Factor out the duplicated instantiation context setup/tear down
// code here.
InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
return;
PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
"instantiating variable initializer");
// The instantiation is visible here, even if it was first declared in an
// unimported module.
Var->setVisibleDespiteOwningModule();
// If we're performing recursive template instantiation, create our own
// queue of pending implicit instantiations that we will instantiate
// later, while we're still within our own instantiation context.
GlobalEagerInstantiationScope GlobalInstantiations(*this,
/*Enabled=*/Recursive);
LocalInstantiationScope Local(*this);
LocalEagerInstantiationScope LocalInstantiations(*this);
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
ContextRAII PreviousContext(*this, Var->getDeclContext());
InstantiateVariableInitializer(Var, PatternDecl, TemplateArgs);
PreviousContext.pop();
// This variable may have local implicit instantiations that need to be
// instantiated within this scope.
LocalInstantiations.perform();
Local.Exit();
GlobalInstantiations.perform();
}
} else {
assert(Var->isStaticDataMember() && PatternDecl->isStaticDataMember() &&
"not a static data member?");
}
VarDecl *Def = PatternDecl->getDefinition(getASTContext());
// If we don't have a definition of the variable template, we won't perform
// any instantiation. Rather, we rely on the user to instantiate this
// definition (or provide a specialization for it) in another translation
// unit.
if (!Def && !DefinitionRequired) {
if (TSK == TSK_ExplicitInstantiationDefinition) {
PendingInstantiations.push_back(
std::make_pair(Var, PointOfInstantiation));
} else if (TSK == TSK_ImplicitInstantiation) {
// Warn about missing definition at the end of translation unit.
if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
!getSourceManager().isInSystemHeader(PatternDecl->getBeginLoc())) {
Diag(PointOfInstantiation, diag::warn_var_template_missing)
<< Var;
Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
if (getLangOpts().CPlusPlus11)
Diag(PointOfInstantiation, diag::note_inst_declaration_hint) << Var;
}
return;
}
}
// FIXME: We need to track the instantiation stack in order to know which
// definitions should be visible within this instantiation.
// FIXME: Produce diagnostics when Var->getInstantiatedFromStaticDataMember().
if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Var,
/*InstantiatedFromMember*/false,
PatternDecl, Def, TSK,
/*Complain*/DefinitionRequired))
return;
// C++11 [temp.explicit]p10:
// Except for inline functions, const variables of literal types, variables
// of reference types, [...] explicit instantiation declarations
// have the effect of suppressing the implicit instantiation of the entity
// to which they refer.
//
// FIXME: That's not exactly the same as "might be usable in constant
// expressions", which only allows constexpr variables and const integral
// types, not arbitrary const literal types.
if (TSK == TSK_ExplicitInstantiationDeclaration &&
!Var->mightBeUsableInConstantExpressions(getASTContext()))
return;
// Make sure to pass the instantiated variable to the consumer at the end.
struct PassToConsumerRAII {
ASTConsumer &Consumer;
VarDecl *Var;
PassToConsumerRAII(ASTConsumer &Consumer, VarDecl *Var)
: Consumer(Consumer), Var(Var) { }
~PassToConsumerRAII() {
Consumer.HandleCXXStaticMemberVarInstantiation(Var);
}
} PassToConsumerRAII(Consumer, Var);
// If we already have a definition, we're done.
if (VarDecl *Def = Var->getDefinition()) {
// We may be explicitly instantiating something we've already implicitly
// instantiated.
Def->setTemplateSpecializationKind(Var->getTemplateSpecializationKind(),
PointOfInstantiation);
return;
}
InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
return;
PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
"instantiating variable definition");
// If we're performing recursive template instantiation, create our own
// queue of pending implicit instantiations that we will instantiate later,
// while we're still within our own instantiation context.
GlobalEagerInstantiationScope GlobalInstantiations(*this,
/*Enabled=*/Recursive);
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
ContextRAII PreviousContext(*this, Var->getDeclContext());
LocalInstantiationScope Local(*this);
LocalEagerInstantiationScope LocalInstantiations(*this);
VarDecl *OldVar = Var;
if (Def->isStaticDataMember() && !Def->isOutOfLine()) {
// We're instantiating an inline static data member whose definition was
// provided inside the class.
InstantiateVariableInitializer(Var, Def, TemplateArgs);
} else if (!VarSpec) {
Var = cast_or_null<VarDecl>(SubstDecl(Def, Var->getDeclContext(),
TemplateArgs));
} else if (Var->isStaticDataMember() &&
Var->getLexicalDeclContext()->isRecord()) {
// We need to instantiate the definition of a static data member template,
// and all we have is the in-class declaration of it. Instantiate a separate
// declaration of the definition.
TemplateDeclInstantiator Instantiator(*this, Var->getDeclContext(),
TemplateArgs);
TemplateArgumentListInfo TemplateArgInfo;
if (const ASTTemplateArgumentListInfo *ArgInfo =
VarSpec->getTemplateArgsInfo()) {
TemplateArgInfo.setLAngleLoc(ArgInfo->getLAngleLoc());
TemplateArgInfo.setRAngleLoc(ArgInfo->getRAngleLoc());
for (const TemplateArgumentLoc &Arg : ArgInfo->arguments())
TemplateArgInfo.addArgument(Arg);
}
Var = cast_or_null<VarDecl>(Instantiator.VisitVarTemplateSpecializationDecl(
VarSpec->getSpecializedTemplate(), Def, TemplateArgInfo,
VarSpec->getTemplateArgs().asArray(), VarSpec));
if (Var) {
llvm::PointerUnion<VarTemplateDecl *,
VarTemplatePartialSpecializationDecl *> PatternPtr =
VarSpec->getSpecializedTemplateOrPartial();
if (VarTemplatePartialSpecializationDecl *Partial =
PatternPtr.dyn_cast<VarTemplatePartialSpecializationDecl *>())
cast<VarTemplateSpecializationDecl>(Var)->setInstantiationOf(
Partial, &VarSpec->getTemplateInstantiationArgs());
// Attach the initializer.
InstantiateVariableInitializer(Var, Def, TemplateArgs);
}
} else
// Complete the existing variable's definition with an appropriately
// substituted type and initializer.
Var = CompleteVarTemplateSpecializationDecl(VarSpec, Def, TemplateArgs);
PreviousContext.pop();
if (Var) {
PassToConsumerRAII.Var = Var;
Var->setTemplateSpecializationKind(OldVar->getTemplateSpecializationKind(),
OldVar->getPointOfInstantiation());
}
// This variable may have local implicit instantiations that need to be
// instantiated within this scope.
LocalInstantiations.perform();
Local.Exit();
GlobalInstantiations.perform();
}
void
Sema::InstantiateMemInitializers(CXXConstructorDecl *New,
const CXXConstructorDecl *Tmpl,
const MultiLevelTemplateArgumentList &TemplateArgs) {
SmallVector<CXXCtorInitializer*, 4> NewInits;
bool AnyErrors = Tmpl->isInvalidDecl();
// Instantiate all the initializers.
for (const auto *Init : Tmpl->inits()) {
// Only instantiate written initializers, let Sema re-construct implicit
// ones.
if (!Init->isWritten())
continue;
SourceLocation EllipsisLoc;
if (Init->isPackExpansion()) {
// This is a pack expansion. We should expand it now.
TypeLoc BaseTL = Init->getTypeSourceInfo()->getTypeLoc();
SmallVector<UnexpandedParameterPack, 4> Unexpanded;
collectUnexpandedParameterPacks(BaseTL, Unexpanded);
collectUnexpandedParameterPacks(Init->getInit(), Unexpanded);
bool ShouldExpand = false;
bool RetainExpansion = false;
std::optional<unsigned> NumExpansions;
if (CheckParameterPacksForExpansion(Init->getEllipsisLoc(),
BaseTL.getSourceRange(),
Unexpanded,
TemplateArgs, ShouldExpand,
RetainExpansion,
NumExpansions)) {
AnyErrors = true;
New->setInvalidDecl();
continue;
}
assert(ShouldExpand && "Partial instantiation of base initializer?");
// Loop over all of the arguments in the argument pack(s),
for (unsigned I = 0; I != *NumExpansions; ++I) {
Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
// Instantiate the initializer.
ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
/*CXXDirectInit=*/true);
if (TempInit.isInvalid()) {
AnyErrors = true;
break;
}
// Instantiate the base type.
TypeSourceInfo *BaseTInfo = SubstType(Init->getTypeSourceInfo(),
TemplateArgs,
Init->getSourceLocation(),
New->getDeclName());
if (!BaseTInfo) {
AnyErrors = true;
break;
}
// Build the initializer.
MemInitResult NewInit = BuildBaseInitializer(BaseTInfo->getType(),
BaseTInfo, TempInit.get(),
New->getParent(),
SourceLocation());
if (NewInit.isInvalid()) {
AnyErrors = true;
break;
}
NewInits.push_back(NewInit.get());
}
continue;
}
// Instantiate the initializer.
ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
/*CXXDirectInit=*/true);
if (TempInit.isInvalid()) {
AnyErrors = true;
continue;
}
MemInitResult NewInit;
if (Init->isDelegatingInitializer() || Init->isBaseInitializer()) {
TypeSourceInfo *TInfo = SubstType(Init->getTypeSourceInfo(),
TemplateArgs,
Init->getSourceLocation(),
New->getDeclName());
if (!TInfo) {
AnyErrors = true;
New->setInvalidDecl();
continue;
}
if (Init->isBaseInitializer())
NewInit = BuildBaseInitializer(TInfo->getType(), TInfo, TempInit.get(),
New->getParent(), EllipsisLoc);
else
NewInit = BuildDelegatingInitializer(TInfo, TempInit.get(),
cast<CXXRecordDecl>(CurContext->getParent()));
} else if (Init->isMemberInitializer()) {
FieldDecl *Member = cast_or_null<FieldDecl>(FindInstantiatedDecl(
Init->getMemberLocation(),
Init->getMember(),
TemplateArgs));
if (!Member) {
AnyErrors = true;
New->setInvalidDecl();
continue;
}
NewInit = BuildMemberInitializer(Member, TempInit.get(),
Init->getSourceLocation());
} else if (Init->isIndirectMemberInitializer()) {
IndirectFieldDecl *IndirectMember =
cast_or_null<IndirectFieldDecl>(FindInstantiatedDecl(
Init->getMemberLocation(),
Init->getIndirectMember(), TemplateArgs));
if (!IndirectMember) {
AnyErrors = true;
New->setInvalidDecl();
continue;
}
NewInit = BuildMemberInitializer(IndirectMember, TempInit.get(),
Init->getSourceLocation());
}
if (NewInit.isInvalid()) {
AnyErrors = true;
New->setInvalidDecl();
} else {
NewInits.push_back(NewInit.get());
}
}
// Assign all the initializers to the new constructor.
ActOnMemInitializers(New,
/*FIXME: ColonLoc */
SourceLocation(),
NewInits,
AnyErrors);
}
// TODO: this could be templated if the various decl types used the
// same method name.
static bool isInstantiationOf(ClassTemplateDecl *Pattern,
ClassTemplateDecl *Instance) {
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromMemberTemplate();
} while (Instance);
return false;
}
static bool isInstantiationOf(FunctionTemplateDecl *Pattern,
FunctionTemplateDecl *Instance) {
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromMemberTemplate();
} while (Instance);
return false;
}
static bool
isInstantiationOf(ClassTemplatePartialSpecializationDecl *Pattern,
ClassTemplatePartialSpecializationDecl *Instance) {
Pattern
= cast<ClassTemplatePartialSpecializationDecl>(Pattern->getCanonicalDecl());
do {
Instance = cast<ClassTemplatePartialSpecializationDecl>(
Instance->getCanonicalDecl());
if (Pattern == Instance)
return true;
Instance = Instance->getInstantiatedFromMember();
} while (Instance);
return false;
}
static bool isInstantiationOf(CXXRecordDecl *Pattern,
CXXRecordDecl *Instance) {
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromMemberClass();
} while (Instance);
return false;
}
static bool isInstantiationOf(FunctionDecl *Pattern,
FunctionDecl *Instance) {
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromMemberFunction();
} while (Instance);
return false;
}
static bool isInstantiationOf(EnumDecl *Pattern,
EnumDecl *Instance) {
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromMemberEnum();
} while (Instance);
return false;
}
static bool isInstantiationOf(UsingShadowDecl *Pattern,
UsingShadowDecl *Instance,
ASTContext &C) {
return declaresSameEntity(C.getInstantiatedFromUsingShadowDecl(Instance),
Pattern);
}
static bool isInstantiationOf(UsingDecl *Pattern, UsingDecl *Instance,
ASTContext &C) {
return declaresSameEntity(C.getInstantiatedFromUsingDecl(Instance), Pattern);
}
template<typename T>
static bool isInstantiationOfUnresolvedUsingDecl(T *Pattern, Decl *Other,
ASTContext &Ctx) {
// An unresolved using declaration can instantiate to an unresolved using
// declaration, or to a using declaration or a using declaration pack.
//
// Multiple declarations can claim to be instantiated from an unresolved
// using declaration if it's a pack expansion. We want the UsingPackDecl
// in that case, not the individual UsingDecls within the pack.
bool OtherIsPackExpansion;
NamedDecl *OtherFrom;
if (auto *OtherUUD = dyn_cast<T>(Other)) {
OtherIsPackExpansion = OtherUUD->isPackExpansion();
OtherFrom = Ctx.getInstantiatedFromUsingDecl(OtherUUD);
} else if (auto *OtherUPD = dyn_cast<UsingPackDecl>(Other)) {
OtherIsPackExpansion = true;
OtherFrom = OtherUPD->getInstantiatedFromUsingDecl();
} else if (auto *OtherUD = dyn_cast<UsingDecl>(Other)) {
OtherIsPackExpansion = false;
OtherFrom = Ctx.getInstantiatedFromUsingDecl(OtherUD);
} else {
return false;
}
return Pattern->isPackExpansion() == OtherIsPackExpansion &&
declaresSameEntity(OtherFrom, Pattern);
}
static bool isInstantiationOfStaticDataMember(VarDecl *Pattern,
VarDecl *Instance) {
assert(Instance->isStaticDataMember());
Pattern = Pattern->getCanonicalDecl();
do {
Instance = Instance->getCanonicalDecl();
if (Pattern == Instance) return true;
Instance = Instance->getInstantiatedFromStaticDataMember();
} while (Instance);
return false;
}
// Other is the prospective instantiation
// D is the prospective pattern
static bool isInstantiationOf(ASTContext &Ctx, NamedDecl *D, Decl *Other) {
if (auto *UUD = dyn_cast<UnresolvedUsingTypenameDecl>(D))
return isInstantiationOfUnresolvedUsingDecl(UUD, Other, Ctx);
if (auto *UUD = dyn_cast<UnresolvedUsingValueDecl>(D))
return isInstantiationOfUnresolvedUsingDecl(UUD, Other, Ctx);
if (D->getKind() != Other->getKind())
return false;
if (auto *Record = dyn_cast<CXXRecordDecl>(Other))
return isInstantiationOf(cast<CXXRecordDecl>(D), Record);
if (auto *Function = dyn_cast<FunctionDecl>(Other))
return isInstantiationOf(cast<FunctionDecl>(D), Function);
if (auto *Enum = dyn_cast<EnumDecl>(Other))
return isInstantiationOf(cast<EnumDecl>(D), Enum);
if (auto *Var = dyn_cast<VarDecl>(Other))
if (Var->isStaticDataMember())
return isInstantiationOfStaticDataMember(cast<VarDecl>(D), Var);
if (auto *Temp = dyn_cast<ClassTemplateDecl>(Other))
return isInstantiationOf(cast<ClassTemplateDecl>(D), Temp);
if (auto *Temp = dyn_cast<FunctionTemplateDecl>(Other))
return isInstantiationOf(cast<FunctionTemplateDecl>(D), Temp);
if (auto *PartialSpec =
dyn_cast<ClassTemplatePartialSpecializationDecl>(Other))
return isInstantiationOf(cast<ClassTemplatePartialSpecializationDecl>(D),
PartialSpec);
if (auto *Field = dyn_cast<FieldDecl>(Other)) {
if (!Field->getDeclName()) {
// This is an unnamed field.
return declaresSameEntity(Ctx.getInstantiatedFromUnnamedFieldDecl(Field),
cast<FieldDecl>(D));
}
}
if (auto *Using = dyn_cast<UsingDecl>(Other))
return isInstantiationOf(cast<UsingDecl>(D), Using, Ctx);
if (auto *Shadow = dyn_cast<UsingShadowDecl>(Other))
return isInstantiationOf(cast<UsingShadowDecl>(D), Shadow, Ctx);
return D->getDeclName() &&
D->getDeclName() == cast<NamedDecl>(Other)->getDeclName();
}
template<typename ForwardIterator>
static NamedDecl *findInstantiationOf(ASTContext &Ctx,
NamedDecl *D,
ForwardIterator first,
ForwardIterator last) {
for (; first != last; ++first)
if (isInstantiationOf(Ctx, D, *first))
return cast<NamedDecl>(*first);
return nullptr;
}
/// Finds the instantiation of the given declaration context
/// within the current instantiation.
///
/// \returns NULL if there was an error
DeclContext *Sema::FindInstantiatedContext(SourceLocation Loc, DeclContext* DC,
const MultiLevelTemplateArgumentList &TemplateArgs) {
if (NamedDecl *D = dyn_cast<NamedDecl>(DC)) {
Decl* ID = FindInstantiatedDecl(Loc, D, TemplateArgs, true);
return cast_or_null<DeclContext>(ID);
} else return DC;
}
/// Determine whether the given context is dependent on template parameters at
/// level \p Level or below.
///
/// Sometimes we only substitute an inner set of template arguments and leave
/// the outer templates alone. In such cases, contexts dependent only on the
/// outer levels are not effectively dependent.
static bool isDependentContextAtLevel(DeclContext *DC, unsigned Level) {
if (!DC->isDependentContext())
return false;
if (!Level)
return true;
return cast<Decl>(DC)->getTemplateDepth() > Level;
}
/// Find the instantiation of the given declaration within the
/// current instantiation.
///
/// This routine is intended to be used when \p D is a declaration
/// referenced from within a template, that needs to mapped into the
/// corresponding declaration within an instantiation. For example,
/// given:
///
/// \code
/// template<typename T>
/// struct X {
/// enum Kind {
/// KnownValue = sizeof(T)
/// };
///
/// bool getKind() const { return KnownValue; }
/// };
///
/// template struct X<int>;
/// \endcode
///
/// In the instantiation of X<int>::getKind(), we need to map the \p
/// EnumConstantDecl for \p KnownValue (which refers to
/// X<T>::<Kind>::KnownValue) to its instantiation (X<int>::<Kind>::KnownValue).
/// \p FindInstantiatedDecl performs this mapping from within the instantiation
/// of X<int>.
NamedDecl *Sema::FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
const MultiLevelTemplateArgumentList &TemplateArgs,
bool FindingInstantiatedContext) {
DeclContext *ParentDC = D->getDeclContext();
// Determine whether our parent context depends on any of the template
// arguments we're currently substituting.
bool ParentDependsOnArgs = isDependentContextAtLevel(
ParentDC, TemplateArgs.getNumRetainedOuterLevels());
// FIXME: Parameters of pointer to functions (y below) that are themselves
// parameters (p below) can have their ParentDC set to the translation-unit
// - thus we can not consistently check if the ParentDC of such a parameter
// is Dependent or/and a FunctionOrMethod.
// For e.g. this code, during Template argument deduction tries to
// find an instantiated decl for (T y) when the ParentDC for y is
// the translation unit.
// e.g. template <class T> void Foo(auto (*p)(T y) -> decltype(y())) {}
// float baz(float(*)()) { return 0.0; }
// Foo(baz);
// The better fix here is perhaps to ensure that a ParmVarDecl, by the time
// it gets here, always has a FunctionOrMethod as its ParentDC??
// For now:
// - as long as we have a ParmVarDecl whose parent is non-dependent and
// whose type is not instantiation dependent, do nothing to the decl
// - otherwise find its instantiated decl.
if (isa<ParmVarDecl>(D) && !ParentDependsOnArgs &&
!cast<ParmVarDecl>(D)->getType()->isInstantiationDependentType())
return D;
if (isa<ParmVarDecl>(D) || isa<NonTypeTemplateParmDecl>(D) ||
isa<TemplateTypeParmDecl>(D) || isa<TemplateTemplateParmDecl>(D) ||
(ParentDependsOnArgs && (ParentDC->isFunctionOrMethod() ||
isa<OMPDeclareReductionDecl>(ParentDC) ||
isa<OMPDeclareMapperDecl>(ParentDC))) ||
(isa<CXXRecordDecl>(D) && cast<CXXRecordDecl>(D)->isLambda() &&
cast<CXXRecordDecl>(D)->getTemplateDepth() >
TemplateArgs.getNumRetainedOuterLevels())) {
// D is a local of some kind. Look into the map of local
// declarations to their instantiations.
if (CurrentInstantiationScope) {
if (auto Found = CurrentInstantiationScope->findInstantiationOf(D)) {
if (Decl *FD = Found->dyn_cast<Decl *>())
return cast<NamedDecl>(FD);
int PackIdx = ArgumentPackSubstitutionIndex;
assert(PackIdx != -1 &&
"found declaration pack but not pack expanding");
typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
return cast<NamedDecl>((*Found->get<DeclArgumentPack *>())[PackIdx]);
}
}
// If we're performing a partial substitution during template argument
// deduction, we may not have values for template parameters yet. They
// just map to themselves.
if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
isa<TemplateTemplateParmDecl>(D))
return D;
if (D->isInvalidDecl())
return nullptr;
// Normally this function only searches for already instantiated declaration
// however we have to make an exclusion for local types used before
// definition as in the code:
//
// template<typename T> void f1() {
// void g1(struct x1);
// struct x1 {};
// }
//
// In this case instantiation of the type of 'g1' requires definition of
// 'x1', which is defined later. Error recovery may produce an enum used
// before definition. In these cases we need to instantiate relevant
// declarations here.
bool NeedInstantiate = false;
if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
NeedInstantiate = RD->isLocalClass();
else if (isa<TypedefNameDecl>(D) &&
isa<CXXDeductionGuideDecl>(D->getDeclContext()))
NeedInstantiate = true;
else
NeedInstantiate = isa<EnumDecl>(D);
if (NeedInstantiate) {
Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
CurrentInstantiationScope->InstantiatedLocal(D, Inst);
return cast<TypeDecl>(Inst);
}
// If we didn't find the decl, then we must have a label decl that hasn't
// been found yet. Lazily instantiate it and return it now.
assert(isa<LabelDecl>(D));
Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
assert(Inst && "Failed to instantiate label??");
CurrentInstantiationScope->InstantiatedLocal(D, Inst);
return cast<LabelDecl>(Inst);
}
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
if (!Record->isDependentContext())
return D;
// Determine whether this record is the "templated" declaration describing
// a class template or class template specialization.
ClassTemplateDecl *ClassTemplate = Record->getDescribedClassTemplate();
if (ClassTemplate)
ClassTemplate = ClassTemplate->getCanonicalDecl();
else if (ClassTemplateSpecializationDecl *Spec =
dyn_cast<ClassTemplateSpecializationDecl>(Record))
ClassTemplate = Spec->getSpecializedTemplate()->getCanonicalDecl();
// Walk the current context to find either the record or an instantiation of
// it.
DeclContext *DC = CurContext;
while (!DC->isFileContext()) {
// If we're performing substitution while we're inside the template
// definition, we'll find our own context. We're done.
if (DC->Equals(Record))
return Record;
if (CXXRecordDecl *InstRecord = dyn_cast<CXXRecordDecl>(DC)) {
// Check whether we're in the process of instantiating a class template
// specialization of the template we're mapping.
if (ClassTemplateSpecializationDecl *InstSpec
= dyn_cast<ClassTemplateSpecializationDecl>(InstRecord)){
ClassTemplateDecl *SpecTemplate = InstSpec->getSpecializedTemplate();
if (ClassTemplate && isInstantiationOf(ClassTemplate, SpecTemplate))
return InstRecord;
}
// Check whether we're in the process of instantiating a member class.
if (isInstantiationOf(Record, InstRecord))
return InstRecord;
}
// Move to the outer template scope.
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) {
if (FD->getFriendObjectKind() &&
FD->getNonTransparentDeclContext()->isFileContext()) {
DC = FD->getLexicalDeclContext();
continue;
}
// An implicit deduction guide acts as if it's within the class template
// specialization described by its name and first N template params.
auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FD);
if (Guide && Guide->isImplicit()) {
TemplateDecl *TD = Guide->getDeducedTemplate();
// Convert the arguments to an "as-written" list.
TemplateArgumentListInfo Args(Loc, Loc);
for (TemplateArgument Arg : TemplateArgs.getInnermost().take_front(
TD->getTemplateParameters()->size())) {
ArrayRef<TemplateArgument> Unpacked(Arg);
if (Arg.getKind() == TemplateArgument::Pack)
Unpacked = Arg.pack_elements();
for (TemplateArgument UnpackedArg : Unpacked)
Args.addArgument(
getTrivialTemplateArgumentLoc(UnpackedArg, QualType(), Loc));
}
QualType T = CheckTemplateIdType(TemplateName(TD), Loc, Args);
if (T.isNull())
return nullptr;
CXXRecordDecl *SubstRecord = T->getAsCXXRecordDecl();
if (!SubstRecord) {
// T can be a dependent TemplateSpecializationType when performing a
// substitution for building a deduction guide.
assert(CodeSynthesisContexts.back().Kind ==
CodeSynthesisContext::BuildingDeductionGuides);
// Return a nullptr as a sentinel value, we handle it properly in
// the TemplateInstantiator::TransformInjectedClassNameType
// override, which we transform it to a TemplateSpecializationType.
return nullptr;
}
// Check that this template-id names the primary template and not a
// partial or explicit specialization. (In the latter cases, it's
// meaningless to attempt to find an instantiation of D within the
// specialization.)
// FIXME: The standard doesn't say what should happen here.
if (FindingInstantiatedContext &&
usesPartialOrExplicitSpecialization(
Loc, cast<ClassTemplateSpecializationDecl>(SubstRecord))) {
Diag(Loc, diag::err_specialization_not_primary_template)
<< T << (SubstRecord->getTemplateSpecializationKind() ==
TSK_ExplicitSpecialization);
return nullptr;
}
DC = SubstRecord;
continue;
}
}
DC = DC->getParent();
}
// Fall through to deal with other dependent record types (e.g.,
// anonymous unions in class templates).
}
if (!ParentDependsOnArgs)
return D;
ParentDC = FindInstantiatedContext(Loc, ParentDC, TemplateArgs);
if (!ParentDC)
return nullptr;
if (ParentDC != D->getDeclContext()) {
// We performed some kind of instantiation in the parent context,
// so now we need to look into the instantiated parent context to
// find the instantiation of the declaration D.
// If our context used to be dependent, we may need to instantiate
// it before performing lookup into that context.
bool IsBeingInstantiated = false;
if (CXXRecordDecl *Spec = dyn_cast<CXXRecordDecl>(ParentDC)) {
if (!Spec->isDependentContext()) {
QualType T = Context.getTypeDeclType(Spec);
const RecordType *Tag = T->getAs<RecordType>();
assert(Tag && "type of non-dependent record is not a RecordType");
if (Tag->isBeingDefined())
IsBeingInstantiated = true;
if (!Tag->isBeingDefined() &&
RequireCompleteType(Loc, T, diag::err_incomplete_type))
return nullptr;
ParentDC = Tag->getDecl();
}
}
NamedDecl *Result = nullptr;
// FIXME: If the name is a dependent name, this lookup won't necessarily
// find it. Does that ever matter?
if (auto Name = D->getDeclName()) {
DeclarationNameInfo NameInfo(Name, D->getLocation());
DeclarationNameInfo NewNameInfo =
SubstDeclarationNameInfo(NameInfo, TemplateArgs);
Name = NewNameInfo.getName();
if (!Name)
return nullptr;
DeclContext::lookup_result Found = ParentDC->lookup(Name);
Result = findInstantiationOf(Context, D, Found.begin(), Found.end());
} else {
// Since we don't have a name for the entity we're looking for,
// our only option is to walk through all of the declarations to
// find that name. This will occur in a few cases:
//
// - anonymous struct/union within a template
// - unnamed class/struct/union/enum within a template
//
// FIXME: Find a better way to find these instantiations!
Result = findInstantiationOf(Context, D,
ParentDC->decls_begin(),
ParentDC->decls_end());
}
if (!Result) {
if (isa<UsingShadowDecl>(D)) {
// UsingShadowDecls can instantiate to nothing because of using hiding.
} else if (hasUncompilableErrorOccurred()) {
// We've already complained about some ill-formed code, so most likely
// this declaration failed to instantiate. There's no point in
// complaining further, since this is normal in invalid code.
// FIXME: Use more fine-grained 'invalid' tracking for this.
} else if (IsBeingInstantiated) {
// The class in which this member exists is currently being
// instantiated, and we haven't gotten around to instantiating this
// member yet. This can happen when the code uses forward declarations
// of member classes, and introduces ordering dependencies via
// template instantiation.
Diag(Loc, diag::err_member_not_yet_instantiated)
<< D->getDeclName()
<< Context.getTypeDeclType(cast<CXXRecordDecl>(ParentDC));
Diag(D->getLocation(), diag::note_non_instantiated_member_here);
} else if (EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) {
// This enumeration constant was found when the template was defined,
// but can't be found in the instantiation. This can happen if an
// unscoped enumeration member is explicitly specialized.
EnumDecl *Enum = cast<EnumDecl>(ED->getLexicalDeclContext());
EnumDecl *Spec = cast<EnumDecl>(FindInstantiatedDecl(Loc, Enum,
TemplateArgs));
assert(Spec->getTemplateSpecializationKind() ==
TSK_ExplicitSpecialization);
Diag(Loc, diag::err_enumerator_does_not_exist)
<< D->getDeclName()
<< Context.getTypeDeclType(cast<TypeDecl>(Spec->getDeclContext()));
Diag(Spec->getLocation(), diag::note_enum_specialized_here)
<< Context.getTypeDeclType(Spec);
} else {
// We should have found something, but didn't.
llvm_unreachable("Unable to find instantiation of declaration!");
}
}
D = Result;
}
return D;
}
/// Performs template instantiation for all implicit template
/// instantiations we have seen until this point.
void Sema::PerformPendingInstantiations(bool LocalOnly) {
std::deque<PendingImplicitInstantiation> delayedPCHInstantiations;
while (!PendingLocalImplicitInstantiations.empty() ||
(!LocalOnly && !PendingInstantiations.empty())) {
PendingImplicitInstantiation Inst;
if (PendingLocalImplicitInstantiations.empty()) {
Inst = PendingInstantiations.front();
PendingInstantiations.pop_front();
} else {
Inst = PendingLocalImplicitInstantiations.front();
PendingLocalImplicitInstantiations.pop_front();
}
// Instantiate function definitions
if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Inst.first)) {
bool DefinitionRequired = Function->getTemplateSpecializationKind() ==
TSK_ExplicitInstantiationDefinition;
if (Function->isMultiVersion()) {
getASTContext().forEachMultiversionedFunctionVersion(
Function, [this, Inst, DefinitionRequired](FunctionDecl *CurFD) {
InstantiateFunctionDefinition(/*FIXME:*/ Inst.second, CurFD, true,
DefinitionRequired, true);
if (CurFD->isDefined())
CurFD->setInstantiationIsPending(false);
});
} else {
InstantiateFunctionDefinition(/*FIXME:*/ Inst.second, Function, true,
DefinitionRequired, true);
if (Function->isDefined())
Function->setInstantiationIsPending(false);
}
// Definition of a PCH-ed template declaration may be available only in the TU.
if (!LocalOnly && LangOpts.PCHInstantiateTemplates &&
TUKind == TU_Prefix && Function->instantiationIsPending())
delayedPCHInstantiations.push_back(Inst);
continue;
}
// Instantiate variable definitions
VarDecl *Var = cast<VarDecl>(Inst.first);
assert((Var->isStaticDataMember() ||
isa<VarTemplateSpecializationDecl>(Var)) &&
"Not a static data member, nor a variable template"
" specialization?");
// Don't try to instantiate declarations if the most recent redeclaration
// is invalid.
if (Var->getMostRecentDecl()->isInvalidDecl())
continue;
// Check if the most recent declaration has changed the specialization kind
// and removed the need for implicit instantiation.
switch (Var->getMostRecentDecl()
->getTemplateSpecializationKindForInstantiation()) {
case TSK_Undeclared:
llvm_unreachable("Cannot instantitiate an undeclared specialization.");
case TSK_ExplicitInstantiationDeclaration:
case TSK_ExplicitSpecialization:
continue; // No longer need to instantiate this type.
case TSK_ExplicitInstantiationDefinition:
// We only need an instantiation if the pending instantiation *is* the
// explicit instantiation.
if (Var != Var->getMostRecentDecl())
continue;
break;
case TSK_ImplicitInstantiation:
break;
}
PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
"instantiating variable definition");
bool DefinitionRequired = Var->getTemplateSpecializationKind() ==
TSK_ExplicitInstantiationDefinition;
// Instantiate static data member definitions or variable template
// specializations.
InstantiateVariableDefinition(/*FIXME:*/ Inst.second, Var, true,
DefinitionRequired, true);
}
if (!LocalOnly && LangOpts.PCHInstantiateTemplates)
PendingInstantiations.swap(delayedPCHInstantiations);
}
void Sema::PerformDependentDiagnostics(const DeclContext *Pattern,
const MultiLevelTemplateArgumentList &TemplateArgs) {
for (auto *DD : Pattern->ddiags()) {
switch (DD->getKind()) {
case DependentDiagnostic::Access:
HandleDependentAccessCheck(*DD, TemplateArgs);
break;
}
}
}