C++1y: Allow aggregates to have default initializers.
Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.
There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179958 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 94a5074..b29ce23 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -3054,7 +3054,7 @@
AllToInit.push_back(Init);
// Check whether this initializer makes the field "used".
- if (Init->getInit() && Init->getInit()->HasSideEffects(S.Context))
+ if (Init->getInit()->HasSideEffects(S.Context))
S.UnusedPrivateFields.remove(Init->getAnyMember());
return false;
@@ -3103,16 +3103,18 @@
// has a brace-or-equal-initializer, the entity is initialized as specified
// in [dcl.init].
if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
+ Expr *DIE = CXXDefaultInitExpr::Create(SemaRef.Context,
+ Info.Ctor->getLocation(), Field);
CXXCtorInitializer *Init;
if (Indirect)
Init = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Indirect,
SourceLocation(),
- SourceLocation(), 0,
+ SourceLocation(), DIE,
SourceLocation());
else
Init = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
SourceLocation(),
- SourceLocation(), 0,
+ SourceLocation(), DIE,
SourceLocation());
return Info.addFieldInitializer(Init);
}
diff --git a/lib/Sema/SemaExceptionSpec.cpp b/lib/Sema/SemaExceptionSpec.cpp
index 4758718..1a5f482 100644
--- a/lib/Sema/SemaExceptionSpec.cpp
+++ b/lib/Sema/SemaExceptionSpec.cpp
@@ -1011,7 +1011,6 @@
case Expr::ConditionalOperatorClass:
case Expr::CompoundLiteralExprClass:
case Expr::CXXConstCastExprClass:
- case Expr::CXXDefaultArgExprClass:
case Expr::CXXReinterpretCastExprClass:
case Expr::DesignatedInitExprClass:
case Expr::ExprWithCleanupsClass:
@@ -1044,6 +1043,12 @@
case Expr::StmtExprClass:
return CT_Can;
+ case Expr::CXXDefaultArgExprClass:
+ return canThrow(cast<CXXDefaultArgExpr>(E)->getExpr());
+
+ case Expr::CXXDefaultInitExprClass:
+ return canThrow(cast<CXXDefaultInitExpr>(E)->getExpr());
+
case Expr::ChooseExprClass:
if (E->isTypeDependent() || E->isValueDependent())
return CT_Dependent;
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 5a5fd26..0e51399 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -293,6 +293,21 @@
InitializedEntity MemberEntity
= InitializedEntity::InitializeMember(Field, &ParentEntity);
if (Init >= NumInits || !ILE->getInit(Init)) {
+ // If there's no explicit initializer but we have a default initializer, use
+ // that. This only happens in C++1y, since classes with default
+ // initializers are not aggregates in C++11.
+ if (Field->hasInClassInitializer()) {
+ Expr *DIE = CXXDefaultInitExpr::Create(SemaRef.Context,
+ ILE->getRBraceLoc(), Field);
+ if (Init < NumInits)
+ ILE->setInit(Init, DIE);
+ else {
+ ILE->updateInit(SemaRef.Context, Init, DIE);
+ RequiresSecondPass = true;
+ }
+ return;
+ }
+
// FIXME: We probably don't need to handle references
// specially here, since value-initialization of references is
// handled in InitializationSequence.
@@ -358,15 +373,24 @@
Loc = ILE->getSyntacticForm()->getLocStart();
if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
- if (RType->getDecl()->isUnion() &&
- ILE->getInitializedFieldInUnion())
+ const RecordDecl *RDecl = RType->getDecl();
+ if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
FillInValueInitForField(0, ILE->getInitializedFieldInUnion(),
Entity, ILE, RequiresSecondPass);
- else {
+ else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
+ cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
+ for (RecordDecl::field_iterator Field = RDecl->field_begin(),
+ FieldEnd = RDecl->field_end();
+ Field != FieldEnd; ++Field) {
+ if (Field->hasInClassInitializer()) {
+ FillInValueInitForField(0, *Field, Entity, ILE, RequiresSecondPass);
+ break;
+ }
+ }
+ } else {
unsigned Init = 0;
- for (RecordDecl::field_iterator
- Field = RType->getDecl()->field_begin(),
- FieldEnd = RType->getDecl()->field_end();
+ for (RecordDecl::field_iterator Field = RDecl->field_begin(),
+ FieldEnd = RDecl->field_end();
Field != FieldEnd; ++Field) {
if (Field->isUnnamedBitfield())
continue;
@@ -381,7 +405,7 @@
++Init;
// Only look at the first initialization of a union.
- if (RType->getDecl()->isUnion())
+ if (RDecl->isUnion())
break;
}
}
@@ -1323,8 +1347,23 @@
}
if (DeclType->isUnionType() && IList->getNumInits() == 0) {
- // Value-initialize the first named member of the union.
RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
+
+ // If there's a default initializer, use it.
+ if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
+ if (VerifyOnly)
+ return;
+ for (RecordDecl::field_iterator FieldEnd = RD->field_end();
+ Field != FieldEnd; ++Field) {
+ if (Field->hasInClassInitializer()) {
+ StructuredList->setInitializedFieldInUnion(*Field);
+ // FIXME: Actually build a CXXDefaultInitExpr?
+ return;
+ }
+ }
+ }
+
+ // Value-initialize the first named member of the union.
for (RecordDecl::field_iterator FieldEnd = RD->field_end();
Field != FieldEnd; ++Field) {
if (Field->getDeclName()) {
@@ -1428,7 +1467,7 @@
// Find first (if any) named field and emit warning.
for (RecordDecl::field_iterator it = Field, end = RD->field_end();
it != end; ++it) {
- if (!it->isUnnamedBitfield()) {
+ if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
SemaRef.Diag(IList->getSourceRange().getEnd(),
diag::warn_missing_field_initializers) << it->getName();
break;
@@ -1441,7 +1480,7 @@
!Field->getType()->isIncompleteArrayType()) {
// FIXME: Should check for holes left by designated initializers too.
for (; Field != FieldEnd && !hadError; ++Field) {
- if (!Field->isUnnamedBitfield())
+ if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
CheckValueInitializable(
InitializedEntity::InitializeMember(*Field, &Entity));
}
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 55f1587..97316f8 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -1980,6 +1980,17 @@
Param));
}
+ /// \brief Build a new C++11 default-initialization expression.
+ ///
+ /// By default, builds a new default field initialization expression, which
+ /// does not require any semantic analysis. Subclasses may override this
+ /// routine to provide different behavior.
+ ExprResult RebuildCXXDefaultInitExpr(SourceLocation Loc,
+ FieldDecl *Field) {
+ return getSema().Owned(CXXDefaultInitExpr::Create(getSema().Context, Loc,
+ Field));
+ }
+
/// \brief Build a new C++ zero-initialization expression.
///
/// By default, performs semantic analysis to build the new expression.
@@ -7262,6 +7273,21 @@
template<typename Derived>
ExprResult
+TreeTransform<Derived>::TransformCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
+ FieldDecl *Field
+ = cast_or_null<FieldDecl>(getDerived().TransformDecl(E->getLocStart(),
+ E->getField()));
+ if (!Field)
+ return ExprError();
+
+ if (!getDerived().AlwaysRebuild() && Field == E->getField())
+ return SemaRef.Owned(E);
+
+ return getDerived().RebuildCXXDefaultInitExpr(E->getExprLoc(), Field);
+}
+
+template<typename Derived>
+ExprResult
TreeTransform<Derived>::TransformCXXScalarValueInitExpr(
CXXScalarValueInitExpr *E) {
TypeSourceInfo *T = getDerived().TransformType(E->getTypeSourceInfo());