Extend the self-reference warning to catch when a constructor references itself upon initialization, such as using itself within its own copy constructor.
struct S {};
S s(s);
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138969 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 85352c2..b5cd657 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -5407,41 +5407,88 @@
: public EvaluatedExprVisitor<SelfReferenceChecker> {
Sema &S;
Decl *OrigDecl;
+ bool isRecordType;
+ bool isPODType;
public:
typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
- S(S), OrigDecl(OrigDecl) { }
+ S(S), OrigDecl(OrigDecl) {
+ isPODType = false;
+ isRecordType = false;
+ if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
+ isPODType = VD->getType().isPODType(S.Context);
+ isRecordType = VD->getType()->isRecordType();
+ }
+ }
void VisitExpr(Expr *E) {
if (isa<ObjCMessageExpr>(*E)) return;
+ if (isRecordType) {
+ Expr *expr = E;
+ if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
+ ValueDecl *VD = ME->getMemberDecl();
+ if (isa<EnumConstantDecl>(VD) || isa<VarDecl>(VD)) return;
+ expr = ME->getBase();
+ }
+ if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(expr)) {
+ HandleDeclRefExpr(DRE);
+ return;
+ }
+ }
Inherited::VisitExpr(E);
}
+ void VisitMemberExpr(MemberExpr *E) {
+ if (isa<FieldDecl>(E->getMemberDecl()))
+ if (DeclRefExpr *DRE
+ = dyn_cast<DeclRefExpr>(E->getBase()->IgnoreParenImpCasts())) {
+ HandleDeclRefExpr(DRE);
+ return;
+ }
+ Inherited::VisitMemberExpr(E);
+ }
+
void VisitImplicitCastExpr(ImplicitCastExpr *E) {
- CheckForSelfReference(E);
+ if ((!isRecordType &&E->getCastKind() == CK_LValueToRValue) ||
+ (isRecordType && E->getCastKind() == CK_NoOp)) {
+ Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts();
+ if (MemberExpr *ME = dyn_cast<MemberExpr>(SubExpr))
+ SubExpr = ME->getBase()->IgnoreParenImpCasts();
+ if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr)) {
+ HandleDeclRefExpr(DRE);
+ return;
+ }
+ }
Inherited::VisitImplicitCastExpr(E);
}
- void CheckForSelfReference(ImplicitCastExpr *E) {
- if (E->getCastKind() != CK_LValueToRValue) return;
- Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts();
- DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr);
- if (!DRE) return;
- Decl* ReferenceDecl = DRE->getDecl();
+ void VisitUnaryOperator(UnaryOperator *E) {
+ // For POD record types, addresses of its own members are well-defined.
+ if (isRecordType && isPODType) return;
+ Inherited::VisitUnaryOperator(E);
+ }
+
+ void HandleDeclRefExpr(DeclRefExpr *DRE) {
+ Decl* ReferenceDecl = DRE->getDecl();
if (OrigDecl != ReferenceDecl) return;
LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName,
Sema::NotForRedeclaration);
- S.DiagRuntimeBehavior(SubExpr->getLocStart(), SubExpr,
+ S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
S.PDiag(diag::warn_uninit_self_reference_in_init)
- << Result.getLookupName()
+ << Result.getLookupName()
<< OrigDecl->getLocation()
- << SubExpr->getSourceRange());
+ << DRE->getSourceRange());
}
};
}
+/// CheckSelfReference - Warns if OrigDecl is used in expression E.
+void Sema::CheckSelfReference(Decl* OrigDecl, Expr *E) {
+ SelfReferenceChecker(*this, OrigDecl).VisitExpr(E);
+}
+
/// AddInitializerToDecl - Adds the initializer Init to the
/// declaration dcl. If DirectInit is true, this is C++ direct
/// initialization rather than copy initialization.
@@ -5457,10 +5504,10 @@
// Variables declared within a function/method body are handled
// by a dataflow analysis.
if (!vd->hasLocalStorage() && !vd->isStaticLocal())
- SelfReferenceChecker(*this, RealDecl).VisitExpr(Init);
+ CheckSelfReference(RealDecl, Init);
}
else {
- SelfReferenceChecker(*this, RealDecl).VisitExpr(Init);
+ CheckSelfReference(RealDecl, Init);
}
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 06d530f..bcdd480 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -3078,6 +3078,14 @@
Expr **Args, unsigned NumArgs,
QualType DestType,
InitializationSequence &Sequence) {
+ // Check constructor arguments for self reference.
+ if (DeclaratorDecl *DD = Entity.getDecl())
+ // Parameters arguments are occassionially constructed with itself,
+ // for instance, in recursive functions. Skip them.
+ if (!isa<ParmVarDecl>(DD))
+ for (unsigned i = 0; i < NumArgs; ++i)
+ S.CheckSelfReference(DD, Args[i]);
+
// Build the candidate set directly in the initialization sequence
// structure, so that it will persist if we fail.
OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();