Improve -Wuninitialized warnings for fields that are record types.

Get the record handling code from SelfReferenceChecker into
UninitializedFieldVisitor as well as copying the testcases.

llvm-svn: 218740

clang/lib/Sema/SemaDeclCXX.cpp

@@ -2221,7 +2221,8 @@ namespace {
                               llvm::SmallPtrSetImpl<ValueDecl*> &Decls)
       : Inherited(S.Context), S(S), Decls(Decls) { }
 
-    void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly) {
+    void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
+                          bool AddressOf) {
       if (isa<EnumConstantDecl>(ME->getMemberDecl()))
         return;
 
@@ -2229,6 +2230,8 @@ namespace {
       // or union.
       MemberExpr *FieldME = ME;
 
+      bool AllPODFields = FieldME->getType().isPODType(S.Context);
+
       Expr *Base = ME;
       while (isa<MemberExpr>(Base)) {
         ME = cast<MemberExpr>(Base);
@@ -2240,12 +2243,18 @@ namespace {
           if (!FD->isAnonymousStructOrUnion())
             FieldME = ME;
 
-        Base = ME->getBase();
+        if (!FieldME->getType().isPODType(S.Context))
+          AllPODFields = false;
+
+        Base = ME->getBase()->IgnoreParenImpCasts();
       }
 
       if (!isa<CXXThisExpr>(Base))
         return;
 
+      if (AddressOf && AllPODFields)
+        return;
+
       ValueDecl* FoundVD = FieldME->getMemberDecl();
 
       if (!Decls.count(FoundVD))
@@ -2254,7 +2263,7 @@ namespace {
       const bool IsReference = FoundVD->getType()->isReferenceType();
 
       // Prevent double warnings on use of unbounded references.
-      if (IsReference != CheckReferenceOnly)
+      if (CheckReferenceOnly && !IsReference)
         return;
 
       unsigned diag = IsReference
@@ -2268,44 +2277,51 @@ namespace {
 
     }
 
-    void HandleValue(Expr *E) {
+    void HandleValue(Expr *E, bool AddressOf) {
       E = E->IgnoreParens();
 
       if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
-        HandleMemberExpr(ME, false /*CheckReferenceOnly*/);
+        HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
+                         AddressOf /*AddressOf*/);
         return;
       }
 
       if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
-        HandleValue(CO->getTrueExpr());
+        Visit(CO->getCond());
-        HandleValue(CO->getFalseExpr());
+        HandleValue(CO->getTrueExpr(), AddressOf);
+        HandleValue(CO->getFalseExpr(), AddressOf);
         return;
       }
 
       if (BinaryConditionalOperator *BCO =
               dyn_cast<BinaryConditionalOperator>(E)) {
-        HandleValue(BCO->getFalseExpr());
+        Visit(BCO->getCond());
+        HandleValue(BCO->getFalseExpr(), AddressOf);
         return;
       }
 
       if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
-        HandleValue(OVE->getSourceExpr());
+        HandleValue(OVE->getSourceExpr(), AddressOf);
         return;
       }
 
       if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
         switch (BO->getOpcode()) {
         default:
-          return;
+          break;
         case(BO_PtrMemD):
         case(BO_PtrMemI):
-          HandleValue(BO->getLHS());
+          HandleValue(BO->getLHS(), AddressOf);
+          Visit(BO->getRHS());
           return;
         case(BO_Comma):
-          HandleValue(BO->getRHS());
+          Visit(BO->getLHS());
+          HandleValue(BO->getRHS(), AddressOf);
           return;
         }
       }
+
+      Visit(E);
     }
 
     void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
@@ -2324,14 +2340,14 @@ namespace {
 
     void VisitMemberExpr(MemberExpr *ME) {
       // All uses of unbounded reference fields will warn.
-      HandleMemberExpr(ME, true /*CheckReferenceOnly*/);
+      HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
-
-      Inherited::VisitMemberExpr(ME);
     }
 
     void VisitImplicitCastExpr(ImplicitCastExpr *E) {
-      if (E->getCastKind() == CK_LValueToRValue)
+      if (E->getCastKind() == CK_LValueToRValue) {
-        HandleValue(E->getSubExpr());
+        HandleValue(E->getSubExpr(), false /*AddressOf*/);
+        return;
+      }
 
       Inherited::VisitImplicitCastExpr(E);
     }
@@ -2339,23 +2355,24 @@ namespace {
     void VisitCXXConstructExpr(CXXConstructExpr *E) {
       if (E->getConstructor()->isCopyConstructor()) {
         Expr *ArgExpr = E->getArg(0);
-        if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(ArgExpr)) {
+        if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
-          if (ICE->getCastKind() == CK_NoOp) {
+          if (ILE->getNumInits() == 1)
+            ArgExpr = ILE->getInit(0);
+        if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
+          if (ICE->getCastKind() == CK_NoOp)
             ArgExpr = ICE->getSubExpr();
-          }
+        HandleValue(ArgExpr, false /*AddressOf*/);
-        }
+        return;
-
-        if (MemberExpr *ME = dyn_cast<MemberExpr>(ArgExpr)) {
-          HandleMemberExpr(ME, false /*CheckReferenceOnly*/);
-        }
       }
       Inherited::VisitCXXConstructExpr(E);
     }
 
     void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
       Expr *Callee = E->getCallee();
-      if (isa<MemberExpr>(Callee))
+      if (isa<MemberExpr>(Callee)) {
-        HandleValue(Callee);
+        HandleValue(Callee, false /*AddressOf*/);
+        return;
+      }
 
       Inherited::VisitCXXMemberCallExpr(E);
     }
@@ -2365,7 +2382,8 @@ namespace {
       if (E->getNumArgs() == 1) {
         if (FunctionDecl *FD = E->getDirectCallee()) {
           if (FD->getIdentifier() && FD->getIdentifier()->isStr("move")) {
-            HandleValue(E->getArg(0));
+            HandleValue(E->getArg(0), false /*AddressOf*/);
+            return;
           }
         }
       }
@@ -2383,15 +2401,25 @@ namespace {
               DeclsToRemove.push_back(FD);
 
       if (E->isCompoundAssignmentOp()) {
-        HandleValue(E->getLHS());
+        HandleValue(E->getLHS(), false /*AddressOf*/);
+        Visit(E->getRHS());
+        return;
       }
 
       Inherited::VisitBinaryOperator(E);
     }
 
     void VisitUnaryOperator(UnaryOperator *E) {
-      if (E->isIncrementDecrementOp())
+      if (E->isIncrementDecrementOp()) {
-        HandleValue(E->getSubExpr());
+        HandleValue(E->getSubExpr(), false /*AddressOf*/);
+        return;
+      }
+      if (E->getOpcode() == UO_AddrOf) {
+        if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
+          HandleValue(ME->getBase(), true /*AddressOf*/);
+          return;
+        }
+      }
 
       Inherited::VisitUnaryOperator(E);
     }

clang/test/SemaCXX/uninitialized.cpp

@@ -295,6 +295,61 @@ A a38({a38});  // expected-warning {{variable 'a38' is uninitialized when used w
 A a39 = {a39};  // expected-warning {{variable 'a39' is uninitialized when used within its own initialization}}
 A a40 = A({a40});  // expected-warning {{variable 'a40' is uninitialized when used within its own initialization}}
 
+class T {
+  A a, a2;
+  const A c_a;
+  A* ptr_a;
+
+  T() {}
+  T(bool (*)[1]) : a() {}
+  T(bool (*)[2]) : a2(a.get()) {}
+  T(bool (*)[3]) : a2(a) {}
+  T(bool (*)[4]) : a(&a) {}
+  T(bool (*)[5]) : a(a.zero()) {}
+  T(bool (*)[6]) : a(a.ONE) {}
+  T(bool (*)[7]) : a(getA()) {}
+  T(bool (*)[8]) : a2(getA(a.TWO)) {}
+  T(bool (*)[9]) : a(getA(&a)) {}
+  T(bool (*)[10]) : a(a.count) {}
+
+  T(bool (*)[11]) : a(a) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[12]) : a(a.get()) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[13]) : a(a.num) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[14]) : a(A(a)) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[15]) : a(getA(a.num)) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[16]) : a(&a.num) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[17]) : a(a.get2()) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[18]) : a2(cond ? a2 : a) {}  // expected-warning {{field 'a2' is uninitialized when used here}}
+  T(bool (*)[19]) : a2(cond ? a2 : a) {}  // expected-warning {{field 'a2' is uninitialized when used here}}
+  T(bool (*)[20]) : a{a} {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[21]) : a({a}) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+
+  T(bool (*)[22]) : ptr_a(new A(ptr_a->count)) {}
+  T(bool (*)[23]) : ptr_a(new A(ptr_a->ONE)) {}
+  T(bool (*)[24]) : ptr_a(new A(ptr_a->TWO)) {}
+  T(bool (*)[25]) : ptr_a(new A(ptr_a->zero())) {}
+
+  T(bool (*)[26]) : ptr_a(new A(ptr_a->get())) {}  // expected-warning {{field 'ptr_a' is uninitialized when used here}}
+  T(bool (*)[27]) : ptr_a(new A(ptr_a->get2())) {}  // expected-warning {{field 'ptr_a' is uninitialized when used here}}
+  T(bool (*)[28]) : ptr_a(new A(ptr_a->num)) {}  // expected-warning {{field 'ptr_a' is uninitialized when used here}}
+
+  T(bool (*)[29]) : c_a(c_a) {}  // expected-warning {{field 'c_a' is uninitialized when used here}}
+  T(bool (*)[30]) : c_a(A(c_a)) {}  // expected-warning {{field 'c_a' is uninitialized when used here}}
+
+  T(bool (*)[31]) : a(std::move(a)) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[32]) : a(moveA(std::move(a))) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[33]) : a(A(std::move(a))) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[34]) : a(A(std::move(a))) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[35]) : a2(std::move(x ? a : (37, a2))) {}  // expected-warning {{field 'a2' is uninitialized when used here}}
+
+  T(bool (*)[36]) : a(const_refA(a)) {}
+  T(bool (*)[37]) : a(A(const_refA(a))) {}
+
+  T(bool (*)[38]) : a({a}) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[39]) : a{a} {}  // expected-warning {{field 'a' is uninitialized when used here}}
+  T(bool (*)[40]) : a({a}) {}  // expected-warning {{field 'a' is uninitialized when used here}}
+};
+
 struct B {
   // POD struct.
   int x;
@@ -383,6 +438,44 @@ B b22 = moveB(std::move(b22));  // expected-warning {{variable 'b22' is uninitia
 B b23 = B(std::move(b23));   // expected-warning {{variable 'b23' is uninitialized when used within its own initialization}}
 B b24 = std::move(x ? b23 : (18, b24));  // expected-warning {{variable 'b24' is uninitialized when used within its own initialization}}
 
+class U {
+  B b1, b2;
+  B *ptr1, *ptr2;
+  const B constb = {};
+
+  U() {}
+  U(bool (*)[1]) : b1() {}
+  U(bool (*)[2]) : b2(b1) {}
+  U(bool (*)[3]) : b1{ 5, &b1.x } {}
+  U(bool (*)[4]) : b1(getB()) {}
+  U(bool (*)[5]) : b1(getB(&b1)) {}
+  U(bool (*)[6]) : b1(getB(&b1.x)) {}
+
+  U(bool (*)[7]) : b1(b1) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[8]) : b1(getB(b1.x)) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[9]) : b1(getB(b1.y)) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[10]) : b1(getB(-b1.x)) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+
+  U(bool (*)[11]) : ptr1(0) {}
+  U(bool (*)[12]) : ptr1(0), ptr2(ptr1) {}
+  U(bool (*)[13]) : ptr1(getPtrB()) {}
+  U(bool (*)[14]) : ptr1(getPtrB(&ptr1)) {}
+
+  U(bool (*)[15]) : ptr1(getPtrB(ptr1->x)) {}  // expected-warning {{field 'ptr1' is uninitialized when used here}}
+  U(bool (*)[16]) : ptr2(getPtrB(ptr2->y)) {}  // expected-warning {{field 'ptr2' is uninitialized when used here}}
+
+  U(bool (*)[17]) : b1 { b1.x = 5, b1.y = 0 } {}
+  U(bool (*)[18]) : b1 { b1.x + 1, b1.y } {}  // expected-warning 2{{field 'b1' is uninitialized when used here}}
+
+  U(bool (*)[19]) : constb(constb) {}  // expected-warning {{field 'constb' is uninitialized when used here}}
+  U(bool (*)[20]) : constb(B(constb)) {}  // expected-warning {{field 'constb' is uninitialized when used here}}
+
+  U(bool (*)[21]) : b1(std::move(b1)) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[22]) : b1(moveB(std::move(b1))) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[23]) : b1(B(std::move(b1))) {}  // expected-warning {{field 'b1' is uninitialized when used here}}
+  U(bool (*)[24]) : b2(std::move(x ? b1 : (18, b2))) {}  // expected-warning {{field 'b2' is uninitialized when used here}}
+};
+
 struct C { char a[100], *e; } car = { .e = car.a };
 
 // <rdar://problem/10398199>