1 files changed, 67 insertions, 0 deletions
diff --git a/test/Analysis/cast-to-struct.cpp b/test/Analysis/cast-to-struct.cpp
new file mode 100644
index 0000000000000..45d55947c9377
--- /dev/null
+++ b/test/Analysis/cast-to-struct.cpp
@@ -0,0 +1,67 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=alpha.core.CastToStruct,core -verify %s
+
+struct AB {
+  int A;
+  int B;
+};
+
+struct ABC {
+  int A;
+  int B;
+  int C;
+};
+
+struct Base {
+  Base() : A(0), B(0) {}
+  virtual ~Base() {}
+
+  int A;
+  int B;
+};
+
+struct Derived : public Base {
+  Derived() : Base(), C(0) {}
+  int C;
+};
+
+void structToStruct(struct AB *P) {
+  struct AB Ab;
+  struct ABC *Abc;
+  Abc = (struct ABC *)&Ab; // expected-warning {{Casting data to a larger structure type and accessing a field can lead to memory access errors or data corruption}}
+  Abc = (struct ABC *)P; // No warning; It is not known what data P points at.
+  Abc = (struct ABC *)&*P;
+
+  // Don't warn when the cast is not widening.
+  P = (struct AB *)&Ab; // struct AB * => struct AB *
+  struct ABC Abc2;
+  P = (struct AB *)&Abc2; // struct ABC * => struct AB *
+
+  // True negatives when casting from Base to Derived.
+  Derived D1, *D2;
+  Base &B1 = D1;
+  D2 = (Derived *)&B1;
+  D2 = dynamic_cast<Derived *>(&B1);
+  D2 = static_cast<Derived *>(&B1);
+
+  // True positives when casting from Base to Derived.
+  Base B2;
+  D2 = (Derived *)&B2;// expected-warning {{Casting data to a larger structure type and accessing a field can lead to memory access errors or data corruption}}
+  D2 = dynamic_cast<Derived *>(&B2);// expected-warning {{Casting data to a larger structure type and accessing a field can lead to memory access errors or data corruption}}
+  D2 = static_cast<Derived *>(&B2);// expected-warning {{Casting data to a larger structure type and accessing a field can lead to memory access errors or data corruption}}
+
+  // False negatives, cast from Base to Derived. With path sensitive analysis
+  // these false negatives could be fixed.
+  Base *B3 = &B2;
+  D2 = (Derived *)B3;
+  D2 = dynamic_cast<Derived *>(B3);
+  D2 = static_cast<Derived *>(B3);
+}
+
+void intToStruct(int *P) {
+  struct ABC *Abc;
+  Abc = (struct ABC *)P; // expected-warning {{Casting a non-structure type to a structure type and accessing a field can lead to memory access errors or data corruption}}
+
+  // Cast from void *.
+  void *VP = P;
+  Abc = (struct ABC *)VP;
+}