Implement C++1y decltype(auto).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180610 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/DeclSpec.cpp b/lib/Sema/DeclSpec.cpp
index 7a69eef..998e2c0 100644
--- a/lib/Sema/DeclSpec.cpp
+++ b/lib/Sema/DeclSpec.cpp
@@ -294,6 +294,11 @@
case TST_event_t:
return false;
+ case TST_decltype_auto:
+ // This must have an initializer, so can't be a function declaration,
+ // even if the initializer has function type.
+ return false;
+
case TST_decltype:
case TST_typeofExpr:
if (Expr *E = DS.getRepAsExpr())
@@ -434,6 +439,7 @@
case DeclSpec::TST_typeofExpr: return "typeof";
case DeclSpec::TST_auto: return "auto";
case DeclSpec::TST_decltype: return "(decltype)";
+ case DeclSpec::TST_decltype_auto: return "decltype(auto)";
case DeclSpec::TST_underlyingType: return "__underlying_type";
case DeclSpec::TST_unknown_anytype: return "__unknown_anytype";
case DeclSpec::TST_atomic: return "_Atomic";
@@ -494,7 +500,7 @@
}
if (StorageClassSpec != SCS_unspecified) {
- // Maybe this is an attempt to use C++0x 'auto' outside of C++0x mode.
+ // Maybe this is an attempt to use C++11 'auto' outside of C++11 mode.
bool isInvalid = true;
if (TypeSpecType == TST_unspecified && S.getLangOpts().CPlusPlus) {
if (SC == SCS_auto)
@@ -834,6 +840,39 @@
// Check the type specifier components first.
+ // If decltype(auto) is used, no other type specifiers are permitted.
+ if (TypeSpecType == TST_decltype_auto &&
+ (TypeSpecWidth != TSW_unspecified ||
+ TypeSpecComplex != TSC_unspecified ||
+ TypeSpecSign != TSS_unspecified ||
+ TypeAltiVecVector || TypeAltiVecPixel || TypeAltiVecBool ||
+ TypeQualifiers)) {
+ const int NumLocs = 8;
+ SourceLocation ExtraLocs[NumLocs] = {
+ TSWLoc, TSCLoc, TSSLoc, AltiVecLoc,
+ TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc
+ };
+ FixItHint Hints[NumLocs];
+ SourceLocation FirstLoc;
+ for (unsigned I = 0; I != NumLocs; ++I) {
+ if (!ExtraLocs[I].isInvalid()) {
+ if (FirstLoc.isInvalid() ||
+ PP.getSourceManager().isBeforeInTranslationUnit(ExtraLocs[I],
+ FirstLoc))
+ FirstLoc = ExtraLocs[I];
+ Hints[I] = FixItHint::CreateRemoval(ExtraLocs[I]);
+ }
+ }
+ TypeSpecWidth = TSW_unspecified;
+ TypeSpecComplex = TSC_unspecified;
+ TypeSpecSign = TSS_unspecified;
+ TypeAltiVecVector = TypeAltiVecPixel = TypeAltiVecBool = false;
+ TypeQualifiers = 0;
+ Diag(D, TSTLoc, diag::err_decltype_auto_cannot_be_combined)
+ << Hints[0] << Hints[1] << Hints[2] << Hints[3]
+ << Hints[4] << Hints[5] << Hints[6] << Hints[7];
+ }
+
// Validate and finalize AltiVec vector declspec.
if (TypeAltiVecVector) {
if (TypeAltiVecBool) {
@@ -973,7 +1012,7 @@
StorageClassSpecLoc = SourceLocation();
}
// Diagnose if we've recovered from an ill-formed 'auto' storage class
- // specifier in a pre-C++0x dialect of C++.
+ // specifier in a pre-C++11 dialect of C++.
if (!PP.getLangOpts().CPlusPlus11 && TypeSpecType == TST_auto)
Diag(D, TSTLoc, diag::ext_auto_type_specifier);
if (PP.getLangOpts().CPlusPlus && !PP.getLangOpts().CPlusPlus11 &&
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 53f726b..3d4f97f 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -4844,8 +4844,7 @@
// If this decl has an auto type in need of deduction, make a note of the
// Decl so we can diagnose uses of it in its own initializer.
- if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto &&
- R->getContainedAutoType())
+ if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
ParsingInitForAutoVars.insert(NewVD);
if (D.isInvalidType() || Invalid)
@@ -8166,7 +8165,7 @@
getASTContext().addUnnamedTag(Tag);
return BuildDeclaratorGroup(Decls.data(), Decls.size(),
- DS.getTypeSpecType() == DeclSpec::TST_auto);
+ DS.containsPlaceholderType());
}
/// BuildDeclaratorGroup - convert a list of declarations into a declaration
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index ba2291e..65ad83d 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -996,7 +996,7 @@
SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
SourceLocation PlacementRParen, SourceRange TypeIdParens,
Declarator &D, Expr *Initializer) {
- bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto;
+ bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType();
Expr *ArraySize = 0;
// If the specified type is an array, unwrap it and save the expression.
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index d559833..a681371 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -3579,11 +3579,13 @@
// auto type deduced as T" in order for [temp.deduct.call]p3 to apply.
if (isa<TemplateTypeParmType>(Replacement)) {
QualType Result = Replacement;
- TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
+ TemplateTypeParmTypeLoc NewTL =
+ TLB.push<TemplateTypeParmTypeLoc>(Result);
NewTL.setNameLoc(TL.getNameLoc());
return Result;
} else {
- QualType Result = RebuildAutoType(Replacement);
+ QualType Result = RebuildAutoType(Replacement,
+ TL.getTypePtr()->isDecltypeAuto());
AutoTypeLoc NewTL = TLB.push<AutoTypeLoc>(Result);
NewTL.setNameLoc(TL.getNameLoc());
return Result;
@@ -3657,6 +3659,24 @@
return DAR_Succeeded;
}
+ // If this is a 'decltype(auto)' specifier, do the decltype dance.
+ // Since 'decltype(auto)' can only occur at the top of the type, we
+ // don't need to go digging for it.
+ if (const AutoType *AT = Type->getType()->getAs<AutoType>()) {
+ if (AT->isDecltypeAuto()) {
+ if (isa<InitListExpr>(Init)) {
+ Diag(Init->getLocStart(), diag::err_decltype_auto_initializer_list);
+ return DAR_FailedAlreadyDiagnosed;
+ }
+
+ QualType Deduced = BuildDecltypeType(Init, Init->getLocStart());
+ // FIXME: Support a non-canonical deduced type for 'auto'.
+ Deduced = Context.getCanonicalType(Deduced);
+ Result = SubstituteAutoTransform(*this, Deduced).TransformType(Type);
+ return DAR_Succeeded;
+ }
+ }
+
SourceLocation Loc = Init->getExprLoc();
LocalInstantiationScope InstScope(*this);
diff --git a/lib/Sema/SemaTemplateVariadic.cpp b/lib/Sema/SemaTemplateVariadic.cpp
index c0ad2be..db885ae 100644
--- a/lib/Sema/SemaTemplateVariadic.cpp
+++ b/lib/Sema/SemaTemplateVariadic.cpp
@@ -727,6 +727,7 @@
case TST_interface:
case TST_class:
case TST_auto:
+ case TST_decltype_auto:
case TST_unknown_anytype:
case TST_image1d_t:
case TST_image1d_array_t:
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 5289d15..8bf5143 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -994,11 +994,14 @@
}
break;
- case DeclSpec::TST_auto: {
+ case DeclSpec::TST_auto:
// TypeQuals handled by caller.
- Result = Context.getAutoType(QualType());
+ Result = Context.getAutoType(QualType(), /*decltype(auto)*/false);
break;
- }
+
+ case DeclSpec::TST_decltype_auto:
+ Result = Context.getAutoType(QualType(), /*decltype(auto)*/true);
+ break;
case DeclSpec::TST_unknown_anytype:
Result = Context.UnknownAnyTy;
@@ -1457,12 +1460,6 @@
return QualType();
}
- if (T->getContainedAutoType()) {
- Diag(Loc, diag::err_illegal_decl_array_of_auto)
- << getPrintableNameForEntity(Entity) << T;
- return QualType();
- }
-
if (const RecordType *EltTy = T->getAs<RecordType>()) {
// If the element type is a struct or union that contains a variadic
// array, accept it as a GNU extension: C99 6.7.2.1p2.
@@ -2063,7 +2060,7 @@
// In C++11, a function declarator using 'auto' must have a trailing return
// type (this is checked later) and we can skip this. In other languages
// using auto, we need to check regardless.
- if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto &&
+ if (D.getDeclSpec().containsPlaceholderType() &&
(!SemaRef.getLangOpts().CPlusPlus11 || !D.isFunctionDeclarator())) {
int Error = -1;
@@ -2402,6 +2399,46 @@
(T->castAs<FunctionProtoType>()->getTypeQuals() != 0 ||
T->castAs<FunctionProtoType>()->getRefQualifier() != RQ_None);
+ // If T is 'decltype(auto)', the only declarators we can have are parens
+ // and at most one function declarator if this is a function declaration.
+ if (const AutoType *AT = T->getAs<AutoType>()) {
+ if (AT->isDecltypeAuto()) {
+ for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
+ unsigned Index = E - I - 1;
+ DeclaratorChunk &DeclChunk = D.getTypeObject(Index);
+ unsigned DiagId = diag::err_decltype_auto_compound_type;
+ unsigned DiagKind = 0;
+ switch (DeclChunk.Kind) {
+ case DeclaratorChunk::Paren:
+ continue;
+ case DeclaratorChunk::Function: {
+ unsigned FnIndex;
+ if (D.isFunctionDeclarationContext() &&
+ D.isFunctionDeclarator(FnIndex) && FnIndex == Index)
+ continue;
+ DiagId = diag::err_decltype_auto_function_declarator_not_declaration;
+ break;
+ }
+ case DeclaratorChunk::Pointer:
+ case DeclaratorChunk::BlockPointer:
+ case DeclaratorChunk::MemberPointer:
+ DiagKind = 0;
+ break;
+ case DeclaratorChunk::Reference:
+ DiagKind = 1;
+ break;
+ case DeclaratorChunk::Array:
+ DiagKind = 2;
+ break;
+ }
+
+ S.Diag(DeclChunk.Loc, DiagId) << DiagKind;
+ D.setInvalidType(true);
+ break;
+ }
+ }
+ }
+
// Walk the DeclTypeInfo, building the recursive type as we go.
// DeclTypeInfos are ordered from the identifier out, which is
// opposite of what we want :).
@@ -2530,6 +2567,15 @@
}
}
+ if (const AutoType *AT = T->getContainedAutoType()) {
+ // We've already diagnosed this for decltype(auto).
+ if (!AT->isDecltypeAuto()) {
+ S.Diag(DeclType.Loc, diag::err_illegal_decl_array_of_auto)
+ << getPrintableNameForEntity(Name) << T;
+ D.setInvalidType(true);
+ }
+ }
+
T = S.BuildArrayType(T, ASM, ArraySize, ATI.TypeQuals,
SourceRange(DeclType.Loc, DeclType.EndLoc), Name);
break;
@@ -2560,7 +2606,8 @@
<< T << D.getDeclSpec().getSourceRange();
D.setInvalidType(true);
} else if (D.getContext() != Declarator::LambdaExprContext &&
- (T.hasQualifiers() || !isa<AutoType>(T))) {
+ (T.hasQualifiers() || !isa<AutoType>(T) ||
+ cast<AutoType>(T)->isDecltypeAuto())) {
S.Diag(D.getDeclSpec().getTypeSpecTypeLoc(),
diag::err_trailing_return_without_auto)
<< T << D.getDeclSpec().getSourceRange();
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 97316f8..c0bc34f 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -754,17 +754,17 @@
UnaryTransformType::UTTKind UKind,
SourceLocation Loc);
- /// \brief Build a new C++0x decltype type.
+ /// \brief Build a new C++11 decltype type.
///
/// By default, performs semantic analysis when building the decltype type.
/// Subclasses may override this routine to provide different behavior.
QualType RebuildDecltypeType(Expr *Underlying, SourceLocation Loc);
- /// \brief Build a new C++0x auto type.
+ /// \brief Build a new C++11 auto type.
///
/// By default, builds a new AutoType with the given deduced type.
- QualType RebuildAutoType(QualType Deduced) {
- return SemaRef.Context.getAutoType(Deduced);
+ QualType RebuildAutoType(QualType Deduced, bool IsDecltypeAuto) {
+ return SemaRef.Context.getAutoType(Deduced, IsDecltypeAuto);
}
/// \brief Build a new template specialization type.
@@ -3407,7 +3407,7 @@
Qs.removeObjCLifetime();
Deduced = SemaRef.Context.getQualifiedType(Deduced.getUnqualifiedType(),
Qs);
- Result = SemaRef.Context.getAutoType(Deduced);
+ Result = SemaRef.Context.getAutoType(Deduced, AutoTy->isDecltypeAuto());
TLB.TypeWasModifiedSafely(Result);
} else {
// Otherwise, complain about the addition of a qualifier to an
@@ -4501,7 +4501,7 @@
QualType Result = TL.getType();
if (getDerived().AlwaysRebuild() || NewDeduced != OldDeduced) {
- Result = getDerived().RebuildAutoType(NewDeduced);
+ Result = getDerived().RebuildAutoType(NewDeduced, T->isDecltypeAuto());
if (Result.isNull())
return QualType();
}