[analyzer][UninitializedObjectChecker] Correct dynamic type is acquired for record pointees

Szelethus · Szelethus · commit 3ef3dd7c8c26 · 2018-09-14T09:13:36.000Z
Differential Revision: https://reviews.llvm.org/D50892 llvm-svn: 342217
diff --git a/clang/lib/StaticAnalyzer/Checkers/UninitializedObject/UninitializedPointee.cpp b/clang/lib/StaticAnalyzer/Checkers/UninitializedObject/UninitializedPointee.cpp
@@ -234,5 +234,13 @@ static llvm::Optional<DereferenceInfo> dereference(ProgramStateRef State,
       break;
   }
 
+  while (R->getAs<CXXBaseObjectRegion>()) {
+    NeedsCastBack = true;
+
+    if (!isa<TypedValueRegion>(R->getSuperRegion()))
+      break;
+    R = R->getSuperRegion()->getAs<TypedValueRegion>();
+  }
+
   return std::make_pair(R, NeedsCastBack);
 }
diff --git a/clang/test/Analysis/cxx-uninitialized-object-inheritance.cpp b/clang/test/Analysis/cxx-uninitialized-object-inheritance.cpp
@@ -781,21 +781,53 @@ void fVirtualDiamondInheritanceTest3() {
 // Dynamic type test.
 //===----------------------------------------------------------------------===//
 
-struct DynTBase {};
-struct DynTDerived : DynTBase {
-  // TODO: we'd expect the note: {{uninitialized field 'this->x'}}
-  int x; // no-note
+struct DynTBase1 {};
+struct DynTDerived1 : DynTBase1 {
+  int y; // expected-note{{uninitialized field 'static_cast<struct DynTDerived1 *>(this->bptr)->y'}}
 };
 
-struct DynamicTypeTest {
-  DynTBase *bptr;
+struct DynamicTypeTest1 {
+  DynTBase1 *bptr;
   int i = 0;
 
-  // TODO: we'd expect the warning: {{1 uninitialized field}}
-  DynamicTypeTest(DynTBase *bptr) : bptr(bptr) {} // no-warning
+  DynamicTypeTest1(DynTBase1 *bptr) : bptr(bptr) {} // expected-warning{{1 uninitialized field}}
 };
 
-void f() {
-  DynTDerived d;
-  DynamicTypeTest t(&d);
+void fDynamicTypeTest1() {
+  DynTDerived1 d;
+  DynamicTypeTest1 t(&d);
 };
+
+struct DynTBase2 {
+  int x; // expected-note{{uninitialized field 'static_cast<struct DynTDerived2 *>(this->bptr)->DynTBase2::x'}}
+};
+struct DynTDerived2 : DynTBase2 {
+  int y; // expected-note{{uninitialized field 'static_cast<struct DynTDerived2 *>(this->bptr)->y'}}
+};
+
+struct DynamicTypeTest2 {
+  DynTBase2 *bptr;
+  int i = 0;
+
+  DynamicTypeTest2(DynTBase2 *bptr) : bptr(bptr) {} // expected-warning{{2 uninitialized fields}}
+};
+
+void fDynamicTypeTest2() {
+  DynTDerived2 d;
+  DynamicTypeTest2 t(&d);
+}
+
+struct SymbolicSuperRegionBase {
+  SymbolicSuperRegionBase() {}
+};
+
+struct SymbolicSuperRegionDerived : SymbolicSuperRegionBase {
+  SymbolicSuperRegionBase *bptr; // no-crash
+  SymbolicSuperRegionDerived(SymbolicSuperRegionBase *bptr) : bptr(bptr) {}
+};
+
+SymbolicSuperRegionDerived *getSymbolicRegion();
+
+void fSymbolicSuperRegionTest() {
+  SymbolicSuperRegionDerived test(getSymbolicRegion());
+}

Original file line number	Diff line number	Diff line change
`@@ -234,5 +234,13 @@ static llvm::Optional<DereferenceInfo> dereference(ProgramStateRef State,`
`234`	`234`	`break;`
`235`	`235`	`}`
`236`	`236`
	`237`	`+ while (R->getAs<CXXBaseObjectRegion>()) {`
	`238`	`+ NeedsCastBack = true;`
	`239`	`+`
	`240`	`+ if (!isa<TypedValueRegion>(R->getSuperRegion()))`
	`241`	`+ break;`
	`242`	`+ R = R->getSuperRegion()->getAs<TypedValueRegion>();`
	`243`	`+ }`
	`244`	`+`
`237`	`245`	`return std::make_pair(R, NeedsCastBack);`
`238`	`246`	`}`