[Concepts] Requires Expressions
Implement support for C++2a requires-expressions.
Re-commit after compilation failure on some platforms due to alignment issues with PointerIntPair.
Differential Revision: https://reviews.llvm.org/D50360
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 2cd158a..f8da1cb 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -1261,7 +1261,8 @@
DeclContext *DC = CurContext;
while (true) {
- if (isa<BlockDecl>(DC) || isa<EnumDecl>(DC) || isa<CapturedDecl>(DC)) {
+ if (isa<BlockDecl>(DC) || isa<EnumDecl>(DC) || isa<CapturedDecl>(DC) ||
+ isa<RequiresExprBodyDecl>(DC)) {
DC = DC->getParent();
} else if (isa<CXXMethodDecl>(DC) &&
cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call &&
diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp
index 018ac2d..93e5b45 100755
--- a/clang/lib/Sema/SemaConcept.cpp
+++ b/clang/lib/Sema/SemaConcept.cpp
@@ -17,7 +17,10 @@
#include "clang/Sema/SemaDiagnostic.h"
#include "clang/Sema/TemplateDeduction.h"
#include "clang/Sema/Template.h"
-#include "clang/AST/ExprCXX.h"
+#include "clang/Sema/Overload.h"
+#include "clang/Sema/Initialization.h"
+#include "clang/Sema/SemaInternal.h"
+#include "clang/AST/ExprConcepts.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/Basic/OperatorPrecedence.h"
#include "llvm/ADT/DenseMap.h"
@@ -336,6 +339,118 @@
return false;
}
+static void diagnoseUnsatisfiedRequirement(Sema &S,
+ concepts::ExprRequirement *Req,
+ bool First) {
+ assert(!Req->isSatisfied()
+ && "Diagnose() can only be used on an unsatisfied requirement");
+ switch (Req->getSatisfactionStatus()) {
+ case concepts::ExprRequirement::SS_Dependent:
+ llvm_unreachable("Diagnosing a dependent requirement");
+ break;
+ case concepts::ExprRequirement::SS_ExprSubstitutionFailure: {
+ auto *SubstDiag = Req->getExprSubstitutionDiagnostic();
+ if (!SubstDiag->DiagMessage.empty())
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_expr_requirement_expr_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity
+ << SubstDiag->DiagMessage;
+ else
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_expr_requirement_expr_unknown_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity;
+ break;
+ }
+ case concepts::ExprRequirement::SS_NoexceptNotMet:
+ S.Diag(Req->getNoexceptLoc(),
+ diag::note_expr_requirement_noexcept_not_met)
+ << (int)First << Req->getExpr();
+ break;
+ case concepts::ExprRequirement::SS_TypeRequirementSubstitutionFailure: {
+ auto *SubstDiag =
+ Req->getReturnTypeRequirement().getSubstitutionDiagnostic();
+ if (!SubstDiag->DiagMessage.empty())
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_expr_requirement_type_requirement_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity
+ << SubstDiag->DiagMessage;
+ else
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_expr_requirement_type_requirement_unknown_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity;
+ break;
+ }
+ case concepts::ExprRequirement::SS_ConstraintsNotSatisfied: {
+ ConceptSpecializationExpr *ConstraintExpr =
+ Req->getReturnTypeRequirementSubstitutedConstraintExpr();
+ if (ConstraintExpr->getTemplateArgsAsWritten()->NumTemplateArgs == 1)
+ // A simple case - expr type is the type being constrained and the concept
+ // was not provided arguments.
+ S.Diag(ConstraintExpr->getBeginLoc(),
+ diag::note_expr_requirement_constraints_not_satisfied_simple)
+ << (int)First << S.BuildDecltypeType(Req->getExpr(),
+ Req->getExpr()->getBeginLoc())
+ << ConstraintExpr->getNamedConcept();
+ else
+ S.Diag(ConstraintExpr->getBeginLoc(),
+ diag::note_expr_requirement_constraints_not_satisfied)
+ << (int)First << ConstraintExpr;
+ S.DiagnoseUnsatisfiedConstraint(ConstraintExpr->getSatisfaction());
+ break;
+ }
+ case concepts::ExprRequirement::SS_Satisfied:
+ llvm_unreachable("We checked this above");
+ }
+}
+
+static void diagnoseUnsatisfiedRequirement(Sema &S,
+ concepts::TypeRequirement *Req,
+ bool First) {
+ assert(!Req->isSatisfied()
+ && "Diagnose() can only be used on an unsatisfied requirement");
+ switch (Req->getSatisfactionStatus()) {
+ case concepts::TypeRequirement::SS_Dependent:
+ llvm_unreachable("Diagnosing a dependent requirement");
+ return;
+ case concepts::TypeRequirement::SS_SubstitutionFailure: {
+ auto *SubstDiag = Req->getSubstitutionDiagnostic();
+ if (!SubstDiag->DiagMessage.empty())
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_type_requirement_substitution_error) << (int)First
+ << SubstDiag->SubstitutedEntity << SubstDiag->DiagMessage;
+ else
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_type_requirement_unknown_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity;
+ return;
+ }
+ default:
+ llvm_unreachable("Unknown satisfaction status");
+ return;
+ }
+}
+
+static void diagnoseUnsatisfiedRequirement(Sema &S,
+ concepts::NestedRequirement *Req,
+ bool First) {
+ if (Req->isSubstitutionFailure()) {
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag =
+ Req->getSubstitutionDiagnostic();
+ if (!SubstDiag->DiagMessage.empty())
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_nested_requirement_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity
+ << SubstDiag->DiagMessage;
+ else
+ S.Diag(SubstDiag->DiagLoc,
+ diag::note_nested_requirement_unknown_substitution_error)
+ << (int)First << SubstDiag->SubstitutedEntity;
+ return;
+ }
+ S.DiagnoseUnsatisfiedConstraint(Req->getConstraintSatisfaction(), First);
+}
+
+
static void diagnoseWellFormedUnsatisfiedConstraintExpr(Sema &S,
Expr *SubstExpr,
bool First = true) {
@@ -412,6 +527,19 @@
}
S.DiagnoseUnsatisfiedConstraint(CSE->getSatisfaction());
return;
+ } else if (auto *RE = dyn_cast<RequiresExpr>(SubstExpr)) {
+ for (concepts::Requirement *Req : RE->getRequirements())
+ if (!Req->isDependent() && !Req->isSatisfied()) {
+ if (auto *E = dyn_cast<concepts::ExprRequirement>(Req))
+ diagnoseUnsatisfiedRequirement(S, E, First);
+ else if (auto *T = dyn_cast<concepts::TypeRequirement>(Req))
+ diagnoseUnsatisfiedRequirement(S, T, First);
+ else
+ diagnoseUnsatisfiedRequirement(
+ S, cast<concepts::NestedRequirement>(Req), First);
+ break;
+ }
+ return;
}
S.Diag(SubstExpr->getSourceRange().getBegin(),
@@ -434,11 +562,11 @@
Record.template get<Expr *>(), First);
}
-void Sema::DiagnoseUnsatisfiedConstraint(
- const ConstraintSatisfaction& Satisfaction) {
+void
+Sema::DiagnoseUnsatisfiedConstraint(const ConstraintSatisfaction& Satisfaction,
+ bool First) {
assert(!Satisfaction.IsSatisfied &&
"Attempted to diagnose a satisfied constraint");
- bool First = true;
for (auto &Pair : Satisfaction.Details) {
diagnoseUnsatisfiedConstraintExpr(*this, Pair.first, Pair.second, First);
First = false;
@@ -446,10 +574,10 @@
}
void Sema::DiagnoseUnsatisfiedConstraint(
- const ASTConstraintSatisfaction &Satisfaction) {
+ const ASTConstraintSatisfaction &Satisfaction,
+ bool First) {
assert(!Satisfaction.IsSatisfied &&
"Attempted to diagnose a satisfied constraint");
- bool First = true;
for (auto &Pair : Satisfaction) {
diagnoseUnsatisfiedConstraintExpr(*this, Pair.first, Pair.second, First);
First = false;
@@ -826,3 +954,67 @@
<< AmbiguousAtomic2->getSourceRange();
return true;
}
+
+concepts::ExprRequirement::ExprRequirement(
+ Expr *E, bool IsSimple, SourceLocation NoexceptLoc,
+ ReturnTypeRequirement Req, SatisfactionStatus Status,
+ ConceptSpecializationExpr *SubstitutedConstraintExpr) :
+ Requirement(IsSimple ? RK_Simple : RK_Compound, Status == SS_Dependent,
+ Status == SS_Dependent &&
+ (E->containsUnexpandedParameterPack() ||
+ Req.containsUnexpandedParameterPack()),
+ Status == SS_Satisfied), Value(E), NoexceptLoc(NoexceptLoc),
+ TypeReq(Req), SubstitutedConstraintExpr(SubstitutedConstraintExpr),
+ Status(Status) {
+ assert((!IsSimple || (Req.isEmpty() && NoexceptLoc.isInvalid())) &&
+ "Simple requirement must not have a return type requirement or a "
+ "noexcept specification");
+ assert((Status > SS_TypeRequirementSubstitutionFailure && Req.isTypeConstraint()) ==
+ (SubstitutedConstraintExpr != nullptr));
+}
+
+concepts::ExprRequirement::ExprRequirement(
+ SubstitutionDiagnostic *ExprSubstDiag, bool IsSimple,
+ SourceLocation NoexceptLoc, ReturnTypeRequirement Req) :
+ Requirement(IsSimple ? RK_Simple : RK_Compound, Req.isDependent(),
+ Req.containsUnexpandedParameterPack(), /*IsSatisfied=*/false),
+ Value(ExprSubstDiag), NoexceptLoc(NoexceptLoc), TypeReq(Req),
+ Status(SS_ExprSubstitutionFailure) {
+ assert((!IsSimple || (Req.isEmpty() && NoexceptLoc.isInvalid())) &&
+ "Simple requirement must not have a return type requirement or a "
+ "noexcept specification");
+}
+
+concepts::ExprRequirement::ReturnTypeRequirement::
+ReturnTypeRequirement(TemplateParameterList *TPL) :
+ TypeConstraintInfo(TPL, 0) {
+ assert(TPL->size() == 1);
+ const TypeConstraint *TC =
+ cast<TemplateTypeParmDecl>(TPL->getParam(0))->getTypeConstraint();
+ assert(TC &&
+ "TPL must have a template type parameter with a type constraint");
+ auto *Constraint =
+ cast_or_null<ConceptSpecializationExpr>(
+ TC->getImmediatelyDeclaredConstraint());
+ bool Dependent = false;
+ if (Constraint->getTemplateArgsAsWritten()) {
+ for (auto &ArgLoc :
+ Constraint->getTemplateArgsAsWritten()->arguments().drop_front(1)) {
+ if (ArgLoc.getArgument().isDependent()) {
+ Dependent = true;
+ break;
+ }
+ }
+ }
+ TypeConstraintInfo.setInt(Dependent ? 1 : 0);
+}
+
+concepts::TypeRequirement::TypeRequirement(TypeSourceInfo *T) :
+ Requirement(RK_Type, T->getType()->isDependentType(),
+ T->getType()->containsUnexpandedParameterPack(),
+ // We reach this ctor with either dependent types (in which
+ // IsSatisfied doesn't matter) or with non-dependent type in
+ // which the existence of the type indicates satisfaction.
+ /*IsSatisfied=*/true
+ ), Value(T),
+ Status(T->getType()->isDependentType() ? SS_Dependent : SS_Satisfied) {}
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 507e4a6..372f3d1 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -6468,6 +6468,8 @@
return true;
if (DC->isRecord())
return false;
+ if (isa<RequiresExprBodyDecl>(DC))
+ return false;
llvm_unreachable("Unexpected context");
}
diff --git a/clang/lib/Sema/SemaExceptionSpec.cpp b/clang/lib/Sema/SemaExceptionSpec.cpp
index 5aedbe7..193eaa3 100644
--- a/clang/lib/Sema/SemaExceptionSpec.cpp
+++ b/clang/lib/Sema/SemaExceptionSpec.cpp
@@ -1386,6 +1386,7 @@
case Expr::StringLiteralClass:
case Expr::SourceLocExprClass:
case Expr::ConceptSpecializationExprClass:
+ case Expr::RequiresExprClass:
// These expressions can never throw.
return CT_Cannot;
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 5f40719..ea4b93e 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -350,6 +350,17 @@
}
}
+ if (isa<ParmVarDecl>(D) && isa<RequiresExprBodyDecl>(D->getDeclContext()) &&
+ !isUnevaluatedContext()) {
+ // C++ [expr.prim.req.nested] p3
+ // A local parameter shall only appear as an unevaluated operand
+ // (Clause 8) within the constraint-expression.
+ Diag(Loc, diag::err_requires_expr_parameter_referenced_in_evaluated_context)
+ << D;
+ Diag(D->getLocation(), diag::note_entity_declared_at) << D;
+ return true;
+ }
+
return false;
}
@@ -1904,7 +1915,7 @@
bool RefersToCapturedVariable =
isa<VarDecl>(D) &&
NeedToCaptureVariable(cast<VarDecl>(D), NameInfo.getLoc());
-
+
DeclRefExpr *E = DeclRefExpr::Create(
Context, NNS, TemplateKWLoc, D, RefersToCapturedVariable, NameInfo, Ty,
VK, FoundD, TemplateArgs, getNonOdrUseReasonInCurrentContext(D));
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 938420d..192c237 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -11,6 +11,7 @@
///
//===----------------------------------------------------------------------===//
+#include "clang/Sema/Template.h"
#include "clang/Sema/SemaInternal.h"
#include "TreeTransform.h"
#include "TypeLocBuilder.h"
@@ -8331,3 +8332,215 @@
return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);
}
+
+concepts::Requirement *Sema::ActOnSimpleRequirement(Expr *E) {
+ return BuildExprRequirement(E, /*IsSimple=*/true,
+ /*NoexceptLoc=*/SourceLocation(),
+ /*ReturnTypeRequirement=*/{});
+}
+
+concepts::Requirement *
+Sema::ActOnTypeRequirement(SourceLocation TypenameKWLoc, CXXScopeSpec &SS,
+ SourceLocation NameLoc, IdentifierInfo *TypeName,
+ TemplateIdAnnotation *TemplateId) {
+ assert(((!TypeName && TemplateId) || (TypeName && !TemplateId)) &&
+ "Exactly one of TypeName and TemplateId must be specified.");
+ TypeSourceInfo *TSI = nullptr;
+ if (TypeName) {
+ QualType T = CheckTypenameType(ETK_Typename, TypenameKWLoc,
+ SS.getWithLocInContext(Context), *TypeName,
+ NameLoc, &TSI, /*DeducedTypeContext=*/false);
+ if (T.isNull())
+ return nullptr;
+ } else {
+ ASTTemplateArgsPtr ArgsPtr(TemplateId->getTemplateArgs(),
+ TemplateId->NumArgs);
+ TypeResult T = ActOnTypenameType(CurScope, TypenameKWLoc, SS,
+ TemplateId->TemplateKWLoc,
+ TemplateId->Template, TemplateId->Name,
+ TemplateId->TemplateNameLoc,
+ TemplateId->LAngleLoc, ArgsPtr,
+ TemplateId->RAngleLoc);
+ if (T.isInvalid())
+ return nullptr;
+ if (GetTypeFromParser(T.get(), &TSI).isNull())
+ return nullptr;
+ }
+ return BuildTypeRequirement(TSI);
+}
+
+concepts::Requirement *
+Sema::ActOnCompoundRequirement(Expr *E, SourceLocation NoexceptLoc) {
+ return BuildExprRequirement(E, /*IsSimple=*/false, NoexceptLoc,
+ /*ReturnTypeRequirement=*/{});
+}
+
+concepts::Requirement *
+Sema::ActOnCompoundRequirement(
+ Expr *E, SourceLocation NoexceptLoc, CXXScopeSpec &SS,
+ TemplateIdAnnotation *TypeConstraint, unsigned Depth) {
+ // C++2a [expr.prim.req.compound] p1.3.3
+ // [..] the expression is deduced against an invented function template
+ // F [...] F is a void function template with a single type template
+ // parameter T declared with the constrained-parameter. Form a new
+ // cv-qualifier-seq cv by taking the union of const and volatile specifiers
+ // around the constrained-parameter. F has a single parameter whose
+ // type-specifier is cv T followed by the abstract-declarator. [...]
+ //
+ // The cv part is done in the calling function - we get the concept with
+ // arguments and the abstract declarator with the correct CV qualification and
+ // have to synthesize T and the single parameter of F.
+ auto &II = Context.Idents.get("expr-type");
+ auto *TParam = TemplateTypeParmDecl::Create(Context, CurContext,
+ SourceLocation(),
+ SourceLocation(), Depth,
+ /*Index=*/0, &II,
+ /*Typename=*/true,
+ /*ParameterPack=*/false,
+ /*HasTypeConstraint=*/true);
+
+ if (ActOnTypeConstraint(SS, TypeConstraint, TParam,
+ /*EllpsisLoc=*/SourceLocation()))
+ // Just produce a requirement with no type requirements.
+ return BuildExprRequirement(E, /*IsSimple=*/false, NoexceptLoc, {});
+
+ auto *TPL = TemplateParameterList::Create(Context, SourceLocation(),
+ SourceLocation(),
+ ArrayRef<NamedDecl *>(TParam),
+ SourceLocation(),
+ /*RequiresClause=*/nullptr);
+ return BuildExprRequirement(
+ E, /*IsSimple=*/false, NoexceptLoc,
+ concepts::ExprRequirement::ReturnTypeRequirement(TPL));
+}
+
+concepts::ExprRequirement *
+Sema::BuildExprRequirement(
+ Expr *E, bool IsSimple, SourceLocation NoexceptLoc,
+ concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
+ auto Status = concepts::ExprRequirement::SS_Satisfied;
+ ConceptSpecializationExpr *SubstitutedConstraintExpr = nullptr;
+ if (E->isInstantiationDependent() || ReturnTypeRequirement.isDependent())
+ Status = concepts::ExprRequirement::SS_Dependent;
+ else if (NoexceptLoc.isValid() && canThrow(E) == CanThrowResult::CT_Can)
+ Status = concepts::ExprRequirement::SS_NoexceptNotMet;
+ else if (ReturnTypeRequirement.isSubstitutionFailure())
+ Status = concepts::ExprRequirement::SS_TypeRequirementSubstitutionFailure;
+ else if (ReturnTypeRequirement.isTypeConstraint()) {
+ // C++2a [expr.prim.req]p1.3.3
+ // The immediately-declared constraint ([temp]) of decltype((E)) shall
+ // be satisfied.
+ TemplateParameterList *TPL =
+ ReturnTypeRequirement.getTypeConstraintTemplateParameterList();
+ QualType MatchedType =
+ BuildDecltypeType(E, E->getBeginLoc()).getCanonicalType();
+ llvm::SmallVector<TemplateArgument, 1> Args;
+ Args.push_back(TemplateArgument(MatchedType));
+ TemplateArgumentList TAL(TemplateArgumentList::OnStack, Args);
+ MultiLevelTemplateArgumentList MLTAL(TAL);
+ for (unsigned I = 0; I < TPL->getDepth(); ++I)
+ MLTAL.addOuterRetainedLevel();
+ Expr *IDC =
+ cast<TemplateTypeParmDecl>(TPL->getParam(0))->getTypeConstraint()
+ ->getImmediatelyDeclaredConstraint();
+ ExprResult Constraint = SubstExpr(IDC, MLTAL);
+ assert(!Constraint.isInvalid() &&
+ "Substitution cannot fail as it is simply putting a type template "
+ "argument into a concept specialization expression's parameter.");
+
+ SubstitutedConstraintExpr =
+ cast<ConceptSpecializationExpr>(Constraint.get());
+ if (!SubstitutedConstraintExpr->isSatisfied())
+ Status = concepts::ExprRequirement::SS_ConstraintsNotSatisfied;
+ }
+ return new (Context) concepts::ExprRequirement(E, IsSimple, NoexceptLoc,
+ ReturnTypeRequirement, Status,
+ SubstitutedConstraintExpr);
+}
+
+concepts::ExprRequirement *
+Sema::BuildExprRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *ExprSubstitutionDiagnostic,
+ bool IsSimple, SourceLocation NoexceptLoc,
+ concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
+ return new (Context) concepts::ExprRequirement(ExprSubstitutionDiagnostic,
+ IsSimple, NoexceptLoc,
+ ReturnTypeRequirement);
+}
+
+concepts::TypeRequirement *
+Sema::BuildTypeRequirement(TypeSourceInfo *Type) {
+ return new (Context) concepts::TypeRequirement(Type);
+}
+
+concepts::TypeRequirement *
+Sema::BuildTypeRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag) {
+ return new (Context) concepts::TypeRequirement(SubstDiag);
+}
+
+concepts::Requirement *Sema::ActOnNestedRequirement(Expr *Constraint) {
+ return BuildNestedRequirement(Constraint);
+}
+
+concepts::NestedRequirement *
+Sema::BuildNestedRequirement(Expr *Constraint) {
+ ConstraintSatisfaction Satisfaction;
+ if (!Constraint->isInstantiationDependent() &&
+ CheckConstraintSatisfaction(Constraint, Satisfaction))
+ return nullptr;
+ return new (Context) concepts::NestedRequirement(Context, Constraint,
+ Satisfaction);
+}
+
+concepts::NestedRequirement *
+Sema::BuildNestedRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag) {
+ return new (Context) concepts::NestedRequirement(SubstDiag);
+}
+
+RequiresExprBodyDecl *
+Sema::ActOnStartRequiresExpr(SourceLocation RequiresKWLoc,
+ ArrayRef<ParmVarDecl *> LocalParameters,
+ Scope *BodyScope) {
+ assert(BodyScope);
+
+ RequiresExprBodyDecl *Body = RequiresExprBodyDecl::Create(Context, CurContext,
+ RequiresKWLoc);
+
+ PushDeclContext(BodyScope, Body);
+
+ for (ParmVarDecl *Param : LocalParameters) {
+ if (Param->hasDefaultArg())
+ // C++2a [expr.prim.req] p4
+ // [...] A local parameter of a requires-expression shall not have a
+ // default argument. [...]
+ Diag(Param->getDefaultArgRange().getBegin(),
+ diag::err_requires_expr_local_parameter_default_argument);
+ // Ignore default argument and move on
+
+ Param->setDeclContext(Body);
+ // If this has an identifier, add it to the scope stack.
+ if (Param->getIdentifier()) {
+ CheckShadow(BodyScope, Param);
+ PushOnScopeChains(Param, BodyScope);
+ }
+ }
+ return Body;
+}
+
+void Sema::ActOnFinishRequiresExpr() {
+ assert(CurContext && "DeclContext imbalance!");
+ CurContext = CurContext->getLexicalParent();
+ assert(CurContext && "Popped translation unit!");
+}
+
+ExprResult
+Sema::ActOnRequiresExpr(SourceLocation RequiresKWLoc,
+ RequiresExprBodyDecl *Body,
+ ArrayRef<ParmVarDecl *> LocalParameters,
+ ArrayRef<concepts::Requirement *> Requirements,
+ SourceLocation ClosingBraceLoc) {
+ return RequiresExpr::Create(Context, RequiresKWLoc, Body, LocalParameters,
+ Requirements, ClosingBraceLoc);
+}
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 0ed51de..8d96404 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -1575,7 +1575,9 @@
unsigned N = CodeSynthesisContexts.size();
for (unsigned I = CodeSynthesisContextLookupModules.size();
I != N; ++I) {
- Module *M = getDefiningModule(*this, CodeSynthesisContexts[I].Entity);
+ Module *M = CodeSynthesisContexts[I].Entity ?
+ getDefiningModule(*this, CodeSynthesisContexts[I].Entity) :
+ nullptr;
if (M && !LookupModulesCache.insert(M).second)
M = nullptr;
CodeSynthesisContextLookupModules.push_back(M);
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 8a50a9e..661a662 100755
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -10010,24 +10010,12 @@
<< FixItHint::CreateRemoval(TypenameLoc);
NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
+ TypeSourceInfo *TSI = nullptr;
QualType T = CheckTypenameType(TypenameLoc.isValid()? ETK_Typename : ETK_None,
- TypenameLoc, QualifierLoc, II, IdLoc);
+ TypenameLoc, QualifierLoc, II, IdLoc, &TSI,
+ /*DeducedTSTContext=*/true);
if (T.isNull())
return true;
-
- TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
- if (isa<DependentNameType>(T)) {
- DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
- TL.setElaboratedKeywordLoc(TypenameLoc);
- TL.setQualifierLoc(QualifierLoc);
- TL.setNameLoc(IdLoc);
- } else {
- ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
- TL.setElaboratedKeywordLoc(TypenameLoc);
- TL.setQualifierLoc(QualifierLoc);
- TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
- }
-
return CreateParsedType(T, TSI);
}
@@ -10164,6 +10152,35 @@
return true;
}
+QualType
+Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
+ SourceLocation KeywordLoc,
+ NestedNameSpecifierLoc QualifierLoc,
+ const IdentifierInfo &II,
+ SourceLocation IILoc,
+ TypeSourceInfo **TSI,
+ bool DeducedTSTContext) {
+ QualType T = CheckTypenameType(Keyword, KeywordLoc, QualifierLoc, II, IILoc,
+ DeducedTSTContext);
+ if (T.isNull())
+ return QualType();
+
+ *TSI = Context.CreateTypeSourceInfo(T);
+ if (isa<DependentNameType>(T)) {
+ DependentNameTypeLoc TL =
+ (*TSI)->getTypeLoc().castAs<DependentNameTypeLoc>();
+ TL.setElaboratedKeywordLoc(KeywordLoc);
+ TL.setQualifierLoc(QualifierLoc);
+ TL.setNameLoc(IILoc);
+ } else {
+ ElaboratedTypeLoc TL = (*TSI)->getTypeLoc().castAs<ElaboratedTypeLoc>();
+ TL.setElaboratedKeywordLoc(KeywordLoc);
+ TL.setQualifierLoc(QualifierLoc);
+ TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IILoc);
+ }
+ return T;
+}
+
/// Build the type that describes a C++ typename specifier,
/// e.g., "typename T::type".
QualType
@@ -10171,32 +10188,38 @@
SourceLocation KeywordLoc,
NestedNameSpecifierLoc QualifierLoc,
const IdentifierInfo &II,
- SourceLocation IILoc) {
+ SourceLocation IILoc, bool DeducedTSTContext) {
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
- DeclContext *Ctx = computeDeclContext(SS);
- if (!Ctx) {
- // If the nested-name-specifier is dependent and couldn't be
- // resolved to a type, build a typename type.
- assert(QualifierLoc.getNestedNameSpecifier()->isDependent());
- return Context.getDependentNameType(Keyword,
- QualifierLoc.getNestedNameSpecifier(),
- &II);
+ DeclContext *Ctx = nullptr;
+ if (QualifierLoc) {
+ Ctx = computeDeclContext(SS);
+ if (!Ctx) {
+ // If the nested-name-specifier is dependent and couldn't be
+ // resolved to a type, build a typename type.
+ assert(QualifierLoc.getNestedNameSpecifier()->isDependent());
+ return Context.getDependentNameType(Keyword,
+ QualifierLoc.getNestedNameSpecifier(),
+ &II);
+ }
+
+ // If the nested-name-specifier refers to the current instantiation,
+ // the "typename" keyword itself is superfluous. In C++03, the
+ // program is actually ill-formed. However, DR 382 (in C++0x CD1)
+ // allows such extraneous "typename" keywords, and we retroactively
+ // apply this DR to C++03 code with only a warning. In any case we continue.
+
+ if (RequireCompleteDeclContext(SS, Ctx))
+ return QualType();
}
- // If the nested-name-specifier refers to the current instantiation,
- // the "typename" keyword itself is superfluous. In C++03, the
- // program is actually ill-formed. However, DR 382 (in C++0x CD1)
- // allows such extraneous "typename" keywords, and we retroactively
- // apply this DR to C++03 code with only a warning. In any case we continue.
-
- if (RequireCompleteDeclContext(SS, Ctx))
- return QualType();
-
DeclarationName Name(&II);
LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
- LookupQualifiedName(Result, Ctx, SS);
+ if (Ctx)
+ LookupQualifiedName(Result, Ctx, SS);
+ else
+ LookupName(Result, CurScope);
unsigned DiagID = 0;
Decl *Referenced = nullptr;
switch (Result.getResultKind()) {
@@ -10205,7 +10228,7 @@
// a more specific diagnostic.
SourceRange CondRange;
Expr *Cond = nullptr;
- if (isEnableIf(QualifierLoc, II, CondRange, Cond)) {
+ if (Ctx && isEnableIf(QualifierLoc, II, CondRange, Cond)) {
// If we have a condition, narrow it down to the specific failed
// condition.
if (Cond) {
@@ -10221,12 +10244,14 @@
return QualType();
}
- Diag(CondRange.getBegin(), diag::err_typename_nested_not_found_enable_if)
+ Diag(CondRange.getBegin(),
+ diag::err_typename_nested_not_found_enable_if)
<< Ctx << CondRange;
return QualType();
}
- DiagID = diag::err_typename_nested_not_found;
+ DiagID = Ctx ? diag::err_typename_nested_not_found
+ : diag::err_unknown_typename;
break;
}
@@ -10292,6 +10317,19 @@
// is a placeholder for a deduced class type [...].
if (getLangOpts().CPlusPlus17) {
if (auto *TD = getAsTypeTemplateDecl(Result.getFoundDecl())) {
+ if (!DeducedTSTContext) {
+ QualType T(QualifierLoc
+ ? QualifierLoc.getNestedNameSpecifier()->getAsType()
+ : nullptr, 0);
+ if (!T.isNull())
+ Diag(IILoc, diag::err_dependent_deduced_tst)
+ << (int)getTemplateNameKindForDiagnostics(TemplateName(TD)) << T;
+ else
+ Diag(IILoc, diag::err_deduced_tst)
+ << (int)getTemplateNameKindForDiagnostics(TemplateName(TD));
+ Diag(TD->getLocation(), diag::note_template_decl_here);
+ return QualType();
+ }
return Context.getElaboratedType(
Keyword, QualifierLoc.getNestedNameSpecifier(),
Context.getDeducedTemplateSpecializationType(TemplateName(TD),
@@ -10299,12 +10337,14 @@
}
}
- DiagID = diag::err_typename_nested_not_type;
+ DiagID = Ctx ? diag::err_typename_nested_not_type
+ : diag::err_typename_not_type;
Referenced = Result.getFoundDecl();
break;
case LookupResult::FoundOverloaded:
- DiagID = diag::err_typename_nested_not_type;
+ DiagID = Ctx ? diag::err_typename_nested_not_type
+ : diag::err_typename_not_type;
Referenced = *Result.begin();
break;
@@ -10316,9 +10356,14 @@
// type. Emit an appropriate diagnostic and return an error.
SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(),
IILoc);
- Diag(IILoc, DiagID) << FullRange << Name << Ctx;
+ if (Ctx)
+ Diag(IILoc, DiagID) << FullRange << Name << Ctx;
+ else
+ Diag(IILoc, DiagID) << FullRange << Name;
if (Referenced)
- Diag(Referenced->getLocation(), diag::note_typename_refers_here)
+ Diag(Referenced->getLocation(),
+ Ctx ? diag::note_typename_member_refers_here
+ : diag::note_typename_refers_here)
<< Name;
return QualType();
}
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index af41e23..39bc28d 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -26,6 +26,7 @@
#include "clang/Sema/Template.h"
#include "clang/Sema/TemplateDeduction.h"
#include "clang/Sema/TemplateInstCallback.h"
+#include "clang/Sema/SemaConcept.h"
#include "llvm/Support/TimeProfiler.h"
using namespace clang;
@@ -199,8 +200,10 @@
case DeducedTemplateArgumentSubstitution:
case PriorTemplateArgumentSubstitution:
case ConstraintsCheck:
+ case NestedRequirementConstraintsCheck:
return true;
+ case RequirementInstantiation:
case DefaultTemplateArgumentChecking:
case DeclaringSpecialMember:
case DeclaringImplicitEqualityComparison:
@@ -247,7 +250,7 @@
Inst.InstantiationRange = InstantiationRange;
SemaRef.pushCodeSynthesisContext(Inst);
- AlreadyInstantiating =
+ AlreadyInstantiating = !Inst.Entity ? false :
!SemaRef.InstantiatingSpecializations
.insert(std::make_pair(Inst.Entity->getCanonicalDecl(), Inst.Kind))
.second;
@@ -366,6 +369,26 @@
Sema::InstantiatingTemplate::InstantiatingTemplate(
Sema &SemaRef, SourceLocation PointOfInstantiation,
+ concepts::Requirement *Req, sema::TemplateDeductionInfo &DeductionInfo,
+ SourceRange InstantiationRange)
+ : InstantiatingTemplate(
+ SemaRef, CodeSynthesisContext::RequirementInstantiation,
+ PointOfInstantiation, InstantiationRange, /*Entity=*/nullptr,
+ /*Template=*/nullptr, /*TemplateArgs=*/None, &DeductionInfo) {}
+
+
+Sema::InstantiatingTemplate::InstantiatingTemplate(
+ Sema &SemaRef, SourceLocation PointOfInstantiation,
+ concepts::NestedRequirement *Req, ConstraintsCheck,
+ SourceRange InstantiationRange)
+ : InstantiatingTemplate(
+ SemaRef, CodeSynthesisContext::NestedRequirementConstraintsCheck,
+ PointOfInstantiation, InstantiationRange, /*Entity=*/nullptr,
+ /*Template=*/nullptr, /*TemplateArgs=*/None) {}
+
+
+Sema::InstantiatingTemplate::InstantiatingTemplate(
+ Sema &SemaRef, SourceLocation PointOfInstantiation,
ConstraintsCheck, NamedDecl *Template,
ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
: InstantiatingTemplate(
@@ -446,8 +469,9 @@
if (!Invalid) {
if (!AlreadyInstantiating) {
auto &Active = SemaRef.CodeSynthesisContexts.back();
- SemaRef.InstantiatingSpecializations.erase(
- std::make_pair(Active.Entity, Active.Kind));
+ if (Active.Entity)
+ SemaRef.InstantiatingSpecializations.erase(
+ std::make_pair(Active.Entity, Active.Kind));
}
atTemplateEnd(SemaRef.TemplateInstCallbacks, SemaRef,
@@ -684,6 +708,18 @@
<< Active->InstantiationRange;
break;
+ case CodeSynthesisContext::RequirementInstantiation:
+ Diags.Report(Active->PointOfInstantiation,
+ diag::note_template_requirement_instantiation_here)
+ << Active->InstantiationRange;
+ break;
+
+ case CodeSynthesisContext::NestedRequirementConstraintsCheck:
+ Diags.Report(Active->PointOfInstantiation,
+ diag::note_nested_requirement_here)
+ << Active->InstantiationRange;
+ break;
+
case CodeSynthesisContext::DeclaringSpecialMember:
Diags.Report(Active->PointOfInstantiation,
diag::note_in_declaration_of_implicit_special_member)
@@ -788,6 +824,7 @@
case CodeSynthesisContext::ConstraintsCheck:
case CodeSynthesisContext::ParameterMappingSubstitution:
case CodeSynthesisContext::ConstraintNormalization:
+ case CodeSynthesisContext::NestedRequirementConstraintsCheck:
// This is a template instantiation, so there is no SFINAE.
return None;
@@ -802,9 +839,10 @@
case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
case CodeSynthesisContext::ConstraintSubstitution:
- // We're either substituting explicitly-specified template arguments
- // or deduced template arguments or a constraint expression, so SFINAE
- // applies.
+ case CodeSynthesisContext::RequirementInstantiation:
+ // We're either substituting explicitly-specified template arguments,
+ // deduced template arguments, a constraint expression or a requirement
+ // in a requires expression, so SFINAE applies.
assert(Active->DeductionInfo && "Missing deduction info pointer");
return Active->DeductionInfo;
@@ -1056,6 +1094,41 @@
return TreeTransform<TemplateInstantiator>::TransformLambdaExpr(E);
}
+ ExprResult TransformRequiresExpr(RequiresExpr *E) {
+ LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
+ return TreeTransform<TemplateInstantiator>::TransformRequiresExpr(E);
+ }
+
+ bool TransformRequiresExprRequirements(
+ ArrayRef<concepts::Requirement *> Reqs,
+ SmallVectorImpl<concepts::Requirement *> &Transformed) {
+ bool SatisfactionDetermined = false;
+ for (concepts::Requirement *Req : Reqs) {
+ concepts::Requirement *TransReq = nullptr;
+ if (!SatisfactionDetermined) {
+ if (auto *TypeReq = dyn_cast<concepts::TypeRequirement>(Req))
+ TransReq = TransformTypeRequirement(TypeReq);
+ else if (auto *ExprReq = dyn_cast<concepts::ExprRequirement>(Req))
+ TransReq = TransformExprRequirement(ExprReq);
+ else
+ TransReq = TransformNestedRequirement(
+ cast<concepts::NestedRequirement>(Req));
+ if (!TransReq)
+ return true;
+ if (!TransReq->isDependent() && !TransReq->isSatisfied())
+ // [expr.prim.req]p6
+ // [...] The substitution and semantic constraint checking
+ // proceeds in lexical order and stops when a condition that
+ // determines the result of the requires-expression is
+ // encountered. [..]
+ SatisfactionDetermined = true;
+ } else
+ TransReq = Req;
+ Transformed.push_back(TransReq);
+ }
+ return false;
+ }
+
TemplateParameterList *TransformTemplateParameterList(
TemplateParameterList *OrigTPL) {
if (!OrigTPL || !OrigTPL->size()) return OrigTPL;
@@ -1065,6 +1138,14 @@
/* DeclContext *Owner */ Owner, TemplateArgs);
return DeclInstantiator.SubstTemplateParams(OrigTPL);
}
+
+ concepts::TypeRequirement *
+ TransformTypeRequirement(concepts::TypeRequirement *Req);
+ concepts::ExprRequirement *
+ TransformExprRequirement(concepts::ExprRequirement *Req);
+ concepts::NestedRequirement *
+ TransformNestedRequirement(concepts::NestedRequirement *Req);
+
private:
ExprResult transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl *parm,
SourceLocation loc,
@@ -1669,6 +1750,163 @@
return Result;
}
+template<typename EntityPrinter>
+static concepts::Requirement::SubstitutionDiagnostic *
+createSubstDiag(Sema &S, TemplateDeductionInfo &Info, EntityPrinter Printer) {
+ SmallString<128> Message;
+ SourceLocation ErrorLoc;
+ if (Info.hasSFINAEDiagnostic()) {
+ PartialDiagnosticAt PDA(SourceLocation(),
+ PartialDiagnostic::NullDiagnostic{});
+ Info.takeSFINAEDiagnostic(PDA);
+ PDA.second.EmitToString(S.getDiagnostics(), Message);
+ ErrorLoc = PDA.first;
+ } else {
+ ErrorLoc = Info.getLocation();
+ }
+ char *MessageBuf = new (S.Context) char[Message.size()];
+ std::copy(Message.begin(), Message.end(), MessageBuf);
+ SmallString<128> Entity;
+ llvm::raw_svector_ostream OS(Entity);
+ Printer(OS);
+ char *EntityBuf = new (S.Context) char[Entity.size()];
+ std::copy(Entity.begin(), Entity.end(), EntityBuf);
+ return new (S.Context) concepts::Requirement::SubstitutionDiagnostic{
+ StringRef(EntityBuf, Entity.size()), ErrorLoc,
+ StringRef(MessageBuf, Message.size())};
+}
+
+concepts::TypeRequirement *
+TemplateInstantiator::TransformTypeRequirement(concepts::TypeRequirement *Req) {
+ if (!Req->isDependent() && !AlwaysRebuild())
+ return Req;
+ if (Req->isSubstitutionFailure()) {
+ if (AlwaysRebuild())
+ return RebuildTypeRequirement(
+ Req->getSubstitutionDiagnostic());
+ return Req;
+ }
+
+ Sema::SFINAETrap Trap(SemaRef);
+ TemplateDeductionInfo Info(Req->getType()->getTypeLoc().getBeginLoc());
+ Sema::InstantiatingTemplate TypeInst(SemaRef,
+ Req->getType()->getTypeLoc().getBeginLoc(), Req, Info,
+ Req->getType()->getTypeLoc().getSourceRange());
+ if (TypeInst.isInvalid())
+ return nullptr;
+ TypeSourceInfo *TransType = TransformType(Req->getType());
+ if (!TransType || Trap.hasErrorOccurred())
+ return RebuildTypeRequirement(createSubstDiag(SemaRef, Info,
+ [&] (llvm::raw_ostream& OS) {
+ Req->getType()->getType().print(OS, SemaRef.getPrintingPolicy());
+ }));
+ return RebuildTypeRequirement(TransType);
+}
+
+concepts::ExprRequirement *
+TemplateInstantiator::TransformExprRequirement(concepts::ExprRequirement *Req) {
+ if (!Req->isDependent() && !AlwaysRebuild())
+ return Req;
+
+ Sema::SFINAETrap Trap(SemaRef);
+ TemplateDeductionInfo Info(Req->getExpr()->getBeginLoc());
+
+ llvm::PointerUnion<Expr *, concepts::Requirement::SubstitutionDiagnostic *>
+ TransExpr;
+ if (Req->isExprSubstitutionFailure())
+ TransExpr = Req->getExprSubstitutionDiagnostic();
+ else {
+ Sema::InstantiatingTemplate ExprInst(SemaRef, Req->getExpr()->getBeginLoc(),
+ Req, Info,
+ Req->getExpr()->getSourceRange());
+ if (ExprInst.isInvalid())
+ return nullptr;
+ ExprResult TransExprRes = TransformExpr(Req->getExpr());
+ if (TransExprRes.isInvalid() || Trap.hasErrorOccurred())
+ TransExpr = createSubstDiag(SemaRef, Info,
+ [&] (llvm::raw_ostream& OS) {
+ Req->getExpr()->printPretty(OS, nullptr,
+ SemaRef.getPrintingPolicy());
+ });
+ else
+ TransExpr = TransExprRes.get();
+ }
+
+ llvm::Optional<concepts::ExprRequirement::ReturnTypeRequirement> TransRetReq;
+ const auto &RetReq = Req->getReturnTypeRequirement();
+ if (RetReq.isEmpty())
+ TransRetReq.emplace();
+ else if (RetReq.isSubstitutionFailure())
+ TransRetReq.emplace(RetReq.getSubstitutionDiagnostic());
+ else if (RetReq.isTypeConstraint()) {
+ TemplateParameterList *OrigTPL =
+ RetReq.getTypeConstraintTemplateParameterList();
+ Sema::InstantiatingTemplate TPLInst(SemaRef, OrigTPL->getTemplateLoc(),
+ Req, Info, OrigTPL->getSourceRange());
+ if (TPLInst.isInvalid())
+ return nullptr;
+ TemplateParameterList *TPL =
+ TransformTemplateParameterList(OrigTPL);
+ if (!TPL)
+ TransRetReq.emplace(createSubstDiag(SemaRef, Info,
+ [&] (llvm::raw_ostream& OS) {
+ RetReq.getTypeConstraint()->getImmediatelyDeclaredConstraint()
+ ->printPretty(OS, nullptr, SemaRef.getPrintingPolicy());
+ }));
+ else {
+ TPLInst.Clear();
+ TransRetReq.emplace(TPL);
+ }
+ }
+ assert(TransRetReq.hasValue() &&
+ "All code paths leading here must set TransRetReq");
+ if (Expr *E = TransExpr.dyn_cast<Expr *>())
+ return RebuildExprRequirement(E, Req->isSimple(), Req->getNoexceptLoc(),
+ std::move(*TransRetReq));
+ return RebuildExprRequirement(
+ TransExpr.get<concepts::Requirement::SubstitutionDiagnostic *>(),
+ Req->isSimple(), Req->getNoexceptLoc(), std::move(*TransRetReq));
+}
+
+concepts::NestedRequirement *
+TemplateInstantiator::TransformNestedRequirement(
+ concepts::NestedRequirement *Req) {
+ if (!Req->isDependent() && !AlwaysRebuild())
+ return Req;
+ if (Req->isSubstitutionFailure()) {
+ if (AlwaysRebuild())
+ return RebuildNestedRequirement(
+ Req->getSubstitutionDiagnostic());
+ return Req;
+ }
+ Sema::InstantiatingTemplate ReqInst(SemaRef,
+ Req->getConstraintExpr()->getBeginLoc(), Req,
+ Sema::InstantiatingTemplate::ConstraintsCheck{},
+ Req->getConstraintExpr()->getSourceRange());
+
+ ExprResult TransConstraint;
+ TemplateDeductionInfo Info(Req->getConstraintExpr()->getBeginLoc());
+ {
+ EnterExpressionEvaluationContext ContextRAII(
+ SemaRef, Sema::ExpressionEvaluationContext::ConstantEvaluated);
+ Sema::SFINAETrap Trap(SemaRef);
+ Sema::InstantiatingTemplate ConstrInst(SemaRef,
+ Req->getConstraintExpr()->getBeginLoc(), Req, Info,
+ Req->getConstraintExpr()->getSourceRange());
+ if (ConstrInst.isInvalid())
+ return nullptr;
+ TransConstraint = TransformExpr(Req->getConstraintExpr());
+ if (TransConstraint.isInvalid() || Trap.hasErrorOccurred())
+ return RebuildNestedRequirement(createSubstDiag(SemaRef, Info,
+ [&] (llvm::raw_ostream& OS) {
+ Req->getConstraintExpr()->printPretty(OS, nullptr,
+ SemaRef.getPrintingPolicy());
+ }));
+ }
+ return RebuildNestedRequirement(TransConstraint.get());
+}
+
+
/// Perform substitution on the type T with a given set of template
/// arguments.
///
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 64500d0..a470cfc 100755
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3600,6 +3600,12 @@
llvm_unreachable("Concept definitions 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");
}
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index a860640..efb4437 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -2994,6 +2994,9 @@
case DeclaratorContext::PrototypeContext:
Error = 0;
break;
+ case DeclaratorContext::RequiresExprContext:
+ Error = 21;
+ break;
case DeclaratorContext::LambdaExprParameterContext:
// In C++14, generic lambdas allow 'auto' in their parameters.
if (!SemaRef.getLangOpts().CPlusPlus14 ||
@@ -3221,6 +3224,7 @@
case DeclaratorContext::ObjCParameterContext:
case DeclaratorContext::ObjCResultContext:
case DeclaratorContext::KNRTypeListContext:
+ case DeclaratorContext::RequiresExprContext:
// C++ [dcl.fct]p6:
// Types shall not be defined in return or parameter types.
DiagID = diag::err_type_defined_in_param_type;
@@ -4279,6 +4283,7 @@
case DeclaratorContext::TemplateTypeArgContext:
case DeclaratorContext::TypeNameContext:
case DeclaratorContext::FunctionalCastContext:
+ case DeclaratorContext::RequiresExprContext:
// Don't infer in these contexts.
break;
}
@@ -5227,6 +5232,7 @@
switch (D.getContext()) {
case DeclaratorContext::PrototypeContext:
case DeclaratorContext::LambdaExprParameterContext:
+ case DeclaratorContext::RequiresExprContext:
// C++0x [dcl.fct]p13:
// [...] When it is part of a parameter-declaration-clause, the
// parameter pack is a function parameter pack (14.5.3). The type T
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 3b827fb..1f72511 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -19,6 +19,7 @@
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/Expr.h"
+#include "clang/AST/ExprConcepts.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ExprOpenMP.h"
@@ -509,6 +510,15 @@
DeclarationNameInfo
TransformDeclarationNameInfo(const DeclarationNameInfo &NameInfo);
+ bool TransformRequiresExprRequirements(ArrayRef<concepts::Requirement *> Reqs,
+ llvm::SmallVectorImpl<concepts::Requirement *> &Transformed);
+ concepts::TypeRequirement *
+ TransformTypeRequirement(concepts::TypeRequirement *Req);
+ concepts::ExprRequirement *
+ TransformExprRequirement(concepts::ExprRequirement *Req);
+ concepts::NestedRequirement *
+ TransformNestedRequirement(concepts::NestedRequirement *Req);
+
/// Transform the given template name.
///
/// \param SS The nested-name-specifier that qualifies the template
@@ -1056,23 +1066,8 @@
}
if (Keyword == ETK_None || Keyword == ETK_Typename) {
- QualType T = SemaRef.CheckTypenameType(Keyword, KeywordLoc, QualifierLoc,
- *Id, IdLoc);
- // If a dependent name resolves to a deduced template specialization type,
- // check that we're in one of the syntactic contexts permitting it.
- if (!DeducedTSTContext) {
- if (auto *Deduced = dyn_cast_or_null<DeducedTemplateSpecializationType>(
- T.isNull() ? nullptr : T->getContainedDeducedType())) {
- SemaRef.Diag(IdLoc, diag::err_dependent_deduced_tst)
- << (int)SemaRef.getTemplateNameKindForDiagnostics(
- Deduced->getTemplateName())
- << QualType(QualifierLoc.getNestedNameSpecifier()->getAsType(), 0);
- if (auto *TD = Deduced->getTemplateName().getAsTemplateDecl())
- SemaRef.Diag(TD->getLocation(), diag::note_template_decl_here);
- return QualType();
- }
- }
- return T;
+ return SemaRef.CheckTypenameType(Keyword, KeywordLoc, QualifierLoc,
+ *Id, IdLoc, DeducedTSTContext);
}
TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
@@ -3078,7 +3073,56 @@
return Result;
}
- /// \brief Build a new Objective-C boxed expression.
+ /// \brief Build a new requires expression.
+ ///
+ /// By default, performs semantic analysis to build the new expression.
+ /// Subclasses may override this routine to provide different behavior.
+ ExprResult RebuildRequiresExpr(SourceLocation RequiresKWLoc,
+ RequiresExprBodyDecl *Body,
+ ArrayRef<ParmVarDecl *> LocalParameters,
+ ArrayRef<concepts::Requirement *> Requirements,
+ SourceLocation ClosingBraceLoc) {
+ return RequiresExpr::Create(SemaRef.Context, RequiresKWLoc, Body,
+ LocalParameters, Requirements, ClosingBraceLoc);
+ }
+
+ concepts::TypeRequirement *
+ RebuildTypeRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag) {
+ return SemaRef.BuildTypeRequirement(SubstDiag);
+ }
+
+ concepts::TypeRequirement *RebuildTypeRequirement(TypeSourceInfo *T) {
+ return SemaRef.BuildTypeRequirement(T);
+ }
+
+ concepts::ExprRequirement *
+ RebuildExprRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag, bool IsSimple,
+ SourceLocation NoexceptLoc,
+ concepts::ExprRequirement::ReturnTypeRequirement Ret) {
+ return SemaRef.BuildExprRequirement(SubstDiag, IsSimple, NoexceptLoc,
+ std::move(Ret));
+ }
+
+ concepts::ExprRequirement *
+ RebuildExprRequirement(Expr *E, bool IsSimple, SourceLocation NoexceptLoc,
+ concepts::ExprRequirement::ReturnTypeRequirement Ret) {
+ return SemaRef.BuildExprRequirement(E, IsSimple, NoexceptLoc,
+ std::move(Ret));
+ }
+
+ concepts::NestedRequirement *
+ RebuildNestedRequirement(
+ concepts::Requirement::SubstitutionDiagnostic *SubstDiag) {
+ return SemaRef.BuildNestedRequirement(SubstDiag);
+ }
+
+ concepts::NestedRequirement *RebuildNestedRequirement(Expr *Constraint) {
+ return SemaRef.BuildNestedRequirement(Constraint);
+ }
+
+ /// \brief Build a new Objective-C boxed expression.
///
/// By default, performs semantic analysis to build the new expression.
/// Subclasses may override this routine to provide different behavior.
@@ -11179,6 +11223,146 @@
&TransArgs);
}
+template<typename Derived>
+ExprResult
+TreeTransform<Derived>::TransformRequiresExpr(RequiresExpr *E) {
+ SmallVector<ParmVarDecl*, 4> TransParams;
+ SmallVector<QualType, 4> TransParamTypes;
+ Sema::ExtParameterInfoBuilder ExtParamInfos;
+
+ // C++2a [expr.prim.req]p2
+ // Expressions appearing within a requirement-body are unevaluated operands.
+ EnterExpressionEvaluationContext Ctx(
+ SemaRef, Sema::ExpressionEvaluationContext::Unevaluated);
+
+ RequiresExprBodyDecl *Body = RequiresExprBodyDecl::Create(
+ getSema().Context, E->getBody()->getDeclContext(),
+ E->getBody()->getBeginLoc());
+
+ Sema::ContextRAII SavedContext(getSema(), Body, /*NewThisContext*/false);
+
+ if (getDerived().TransformFunctionTypeParams(E->getRequiresKWLoc(),
+ E->getLocalParameters(),
+ /*ParamTypes=*/nullptr,
+ /*ParamInfos=*/nullptr,
+ TransParamTypes, &TransParams,
+ ExtParamInfos))
+ return ExprError();
+
+ for (ParmVarDecl *Param : TransParams)
+ Param->setDeclContext(Body);
+
+ SmallVector<concepts::Requirement *, 4> TransReqs;
+ if (getDerived().TransformRequiresExprRequirements(E->getRequirements(),
+ TransReqs))
+ return ExprError();
+
+ for (concepts::Requirement *Req : TransReqs) {
+ if (auto *ER = dyn_cast<concepts::ExprRequirement>(Req)) {
+ if (ER->getReturnTypeRequirement().isTypeConstraint()) {
+ ER->getReturnTypeRequirement()
+ .getTypeConstraintTemplateParameterList()->getParam(0)
+ ->setDeclContext(Body);
+ }
+ }
+ }
+
+ return getDerived().RebuildRequiresExpr(E->getRequiresKWLoc(), Body,
+ TransParams, TransReqs,
+ E->getRBraceLoc());
+}
+
+template<typename Derived>
+bool TreeTransform<Derived>::TransformRequiresExprRequirements(
+ ArrayRef<concepts::Requirement *> Reqs,
+ SmallVectorImpl<concepts::Requirement *> &Transformed) {
+ for (concepts::Requirement *Req : Reqs) {
+ concepts::Requirement *TransReq = nullptr;
+ if (auto *TypeReq = dyn_cast<concepts::TypeRequirement>(Req))
+ TransReq = getDerived().TransformTypeRequirement(TypeReq);
+ else if (auto *ExprReq = dyn_cast<concepts::ExprRequirement>(Req))
+ TransReq = getDerived().TransformExprRequirement(ExprReq);
+ else
+ TransReq = getDerived().TransformNestedRequirement(
+ cast<concepts::NestedRequirement>(Req));
+ if (!TransReq)
+ return true;
+ Transformed.push_back(TransReq);
+ }
+ return false;
+}
+
+template<typename Derived>
+concepts::TypeRequirement *
+TreeTransform<Derived>::TransformTypeRequirement(
+ concepts::TypeRequirement *Req) {
+ if (Req->isSubstitutionFailure()) {
+ if (getDerived().AlwaysRebuild())
+ return getDerived().RebuildTypeRequirement(
+ Req->getSubstitutionDiagnostic());
+ return Req;
+ }
+ TypeSourceInfo *TransType = getDerived().TransformType(Req->getType());
+ if (!TransType)
+ return nullptr;
+ return getDerived().RebuildTypeRequirement(TransType);
+}
+
+template<typename Derived>
+concepts::ExprRequirement *
+TreeTransform<Derived>::TransformExprRequirement(concepts::ExprRequirement *Req) {
+ llvm::PointerUnion<Expr *, concepts::Requirement::SubstitutionDiagnostic *> TransExpr;
+ if (Req->isExprSubstitutionFailure())
+ TransExpr = Req->getExprSubstitutionDiagnostic();
+ else {
+ ExprResult TransExprRes = getDerived().TransformExpr(Req->getExpr());
+ if (TransExprRes.isInvalid())
+ return nullptr;
+ TransExpr = TransExprRes.get();
+ }
+
+ llvm::Optional<concepts::ExprRequirement::ReturnTypeRequirement> TransRetReq;
+ const auto &RetReq = Req->getReturnTypeRequirement();
+ if (RetReq.isEmpty())
+ TransRetReq.emplace();
+ else if (RetReq.isSubstitutionFailure())
+ TransRetReq.emplace(RetReq.getSubstitutionDiagnostic());
+ else if (RetReq.isTypeConstraint()) {
+ TemplateParameterList *OrigTPL =
+ RetReq.getTypeConstraintTemplateParameterList();
+ TemplateParameterList *TPL =
+ getDerived().TransformTemplateParameterList(OrigTPL);
+ if (!TPL)
+ return nullptr;
+ TransRetReq.emplace(TPL);
+ }
+ assert(TransRetReq.hasValue() &&
+ "All code paths leading here must set TransRetReq");
+ if (Expr *E = TransExpr.dyn_cast<Expr *>())
+ return getDerived().RebuildExprRequirement(E, Req->isSimple(),
+ Req->getNoexceptLoc(),
+ std::move(*TransRetReq));
+ return getDerived().RebuildExprRequirement(
+ TransExpr.get<concepts::Requirement::SubstitutionDiagnostic *>(),
+ Req->isSimple(), Req->getNoexceptLoc(), std::move(*TransRetReq));
+}
+
+template<typename Derived>
+concepts::NestedRequirement *
+TreeTransform<Derived>::TransformNestedRequirement(
+ concepts::NestedRequirement *Req) {
+ if (Req->isSubstitutionFailure()) {
+ if (getDerived().AlwaysRebuild())
+ return getDerived().RebuildNestedRequirement(
+ Req->getSubstitutionDiagnostic());
+ return Req;
+ }
+ ExprResult TransConstraint =
+ getDerived().TransformExpr(Req->getConstraintExpr());
+ if (TransConstraint.isInvalid())
+ return nullptr;
+ return getDerived().RebuildNestedRequirement(TransConstraint.get());
+}
template<typename Derived>
ExprResult