[cfe-commits] r138969 - in /cfe/trunk: include/clang/Sema/Sema.h lib/Sema/SemaDecl.cpp lib/Sema/SemaInit.cpp test/SemaCXX/uninitialized.cpp
Richard Trieu
rtrieu at google.com
Thu Sep 1 14:44:13 PDT 2011
Author: rtrieu
Date: Thu Sep 1 16:44:13 2011
New Revision: 138969
URL: http://llvm.org/viewvc/llvm-project?rev=138969&view=rev
Log:
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);
Modified:
cfe/trunk/include/clang/Sema/Sema.h
cfe/trunk/lib/Sema/SemaDecl.cpp
cfe/trunk/lib/Sema/SemaInit.cpp
cfe/trunk/test/SemaCXX/uninitialized.cpp
Modified: cfe/trunk/include/clang/Sema/Sema.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Sema.h?rev=138969&r1=138968&r2=138969&view=diff
==============================================================================
--- cfe/trunk/include/clang/Sema/Sema.h (original)
+++ cfe/trunk/include/clang/Sema/Sema.h Thu Sep 1 16:44:13 2011
@@ -1035,6 +1035,7 @@
bool SetParamDefaultArgument(ParmVarDecl *Param, Expr *DefaultArg,
SourceLocation EqualLoc);
+ void CheckSelfReference(Decl *OrigDecl, Expr *E);
void AddInitializerToDecl(Decl *dcl, Expr *init, bool DirectInit,
bool TypeMayContainAuto);
void ActOnUninitializedDecl(Decl *dcl, bool TypeMayContainAuto);
Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=138969&r1=138968&r2=138969&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Thu Sep 1 16:44:13 2011
@@ -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)) {
Modified: cfe/trunk/lib/Sema/SemaInit.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaInit.cpp?rev=138969&r1=138968&r2=138969&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaInit.cpp (original)
+++ cfe/trunk/lib/Sema/SemaInit.cpp Thu Sep 1 16:44:13 2011
@@ -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();
Modified: cfe/trunk/test/SemaCXX/uninitialized.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/uninitialized.cpp?rev=138969&r1=138968&r2=138969&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/uninitialized.cpp (original)
+++ cfe/trunk/test/SemaCXX/uninitialized.cpp Thu Sep 1 16:44:13 2011
@@ -24,6 +24,78 @@
int j = far(j);
int k = __alignof__(k);
+
+// Test self-references with record types.
+class A {
+ // Non-POD class.
+ public:
+ enum count { ONE, TWO, THREE };
+ int num;
+ static int count;
+ int get() const { return num; }
+ void set(int x) { num = x; }
+ static int zero() { return 0; }
+
+ A() {}
+ A(A const &a) {}
+ A(int x) {}
+ A(int *x) {}
+ A(A *a) {}
+};
+
+A getA() { return A(); }
+A getA(int x) { return A(); }
+A getA(A* a) { return A(); }
+
+void setupA() {
+ A a1;
+ a1.set(a1.get());
+ A a2(a1.get());
+ A a3(a1);
+ A a4(&a4);
+ A a5(a5.zero());
+ A a6(a6.ONE);
+ A a7 = getA();
+ A a8 = getA(a8.TWO);
+ A a9 = getA(&a9);
+ A a10(a10.count);
+
+ A a11(a11); // expected-warning {{variable 'a11' is uninitialized when used within its own initialization}}
+ A a12(a12.get()); // expected-warning {{variable 'a12' is uninitialized when used within its own initialization}}
+ A a13(a13.num); // expected-warning {{variable 'a13' is uninitialized when used within its own initialization}}
+ A a14 = A(a14); // expected-warning {{variable 'a14' is uninitialized when used within its own initialization}}
+ A a15 = getA(a15.num); // expected-warning {{variable 'a15' is uninitialized when used within its own initialization}}
+ A a16(&a16.num); // expected-warning {{variable 'a16' is uninitialized when used within its own initialization}}
+}
+
+struct B {
+ // POD struct.
+ int x;
+ int *y;
+};
+
+B getB() { return B(); };
+B getB(int x) { return B(); };
+B getB(int *x) { return B(); };
+B getB(B *b) { return B(); };
+
+void setupB() {
+ B b1;
+ B b2(b1);
+ B b3 = { 5, &b3.x };
+ B b4 = getB();
+ B b5 = getB(&b5);
+ B b6 = getB(&b6.x);
+
+ // Silence unused warning
+ (void) b2;
+ (void) b4;
+
+ B b7(b7); // expected-warning {{variable 'b7' is uninitialized when used within its own initialization}}
+ B b8 = getB(b8.x); // expected-warning {{variable 'b8' is uninitialized when used within its own initialization}}
+ B b9 = getB(b9.y); // expected-warning {{variable 'b9' is uninitialized when used within its own initialization}}
+}
+
// Also test similar constructs in a field's initializer.
struct S {
int x;
More information about the cfe-commits
mailing list