clang/test/Analysis/pr37802.cpp

   1 // RUN: %clang_analyze_cc1 -w -analyzer-checker=core -verify %s
   2
   3 // expected-no-diagnostics
   4
   5 typedef __typeof(sizeof(int)) size_t;
   6 void *operator new(size_t, void *h) { return h; }
   7
   8 // I've no idea what this code does, but it used to crash, so let's keep it.
   9 namespace pr37802_v1 {
  10 struct J {
  11   int *p;
  12 };
  13 class X {
  14   void *ar;
  15
  16 public:
  17   X(void *t) : ar(t) {}
  18   template <typename T>
  19   void f(const T &t) {
  20     new (ar) T(t);
  21   }
  22 };
  23 class Y {
  24 public:
  25   template <typename T>
  26   void f(T &&);
  27   void f(J t) {
  28     f(*t.p);
  29   }
  30 };
  31 class Z {
  32   int at() const {}
  33
  34 public:
  35   Z(const Z &other) {
  36     other.au(X(this));
  37   }
  38   template <typename T>
  39   void au(T t) const {
  40     void *c = const_cast<Z *>(this);
  41     if (at()) {
  42       t.f(*static_cast<J *>(c));
  43     } else {
  44       t.f(*static_cast<bool *>(c));
  45     }
  46   }
  47 };
  48 Z g() {
  49   Z az = g();
  50   Z e = az;
  51   Y d;
  52   e.au(d);
  53 }
  54 } // namespace pr37802_v1
  55
  56
  57 // This slightly modified code crashed differently.
  58 namespace pr37802_v2 {
  59 struct J {
  60   int *p;
  61 };
  62
  63 class X {
  64   void *ar;
  65
  66 public:
  67   X(void *t) : ar(t) {}
  68   void f(const J &t) { new (ar) J(t); }
  69   void f(const bool &t) { new (ar) bool(t); }
  70 };
  71
  72 class Y {
  73 public:
  74   void boolf(bool &&);
  75   void f(J &&);
  76   void f(J t) { boolf(*t.p); }
  77 };
  78
  79 class Z {
  80   int at() const {}
  81
  82 public:
  83   Z(const Z &other) { other.au(X(this)); }
  84   void au(X t) const {
  85     void *c = const_cast<Z *>(this);
  86     if (at()) {
  87       t.f(*static_cast<J *>(c));
  88     } else {
  89       t.f(*static_cast<bool *>(c));
  90     }
  91   }
  92   void au(Y t) const {
  93     void *c = const_cast<Z *>(this);
  94     if (at()) {
  95       t.f(*static_cast<J *>(c));
  96     } else {
  97     }
  98   }
  99 };
 100
 101 Z g() {
 102   Z az = g();
 103   Z e = az;
 104   Y d;
 105   e.au(d);
 106 }
 107 } // namespace pr37802_v2