clang/test/Analysis/stack-addr-ps.cpp

   1 // RUN: %clang_analyze_cc1 -analyzer-checker=core -verify %s -Wno-undefined-bool-conversion
   2
   3 typedef __INTPTR_TYPE__ intptr_t;
   4
   5 const int& g() {
   6   int s;
   7   return s; // expected-warning{{Address of stack memory associated with local variable 's' returned}} expected-warning{{reference to stack memory associated with local variable 's' returned}}
   8 }
   9
  10 const int& g2() {
  11   int s1;
  12   int &s2 = s1; // expected-note {{binding reference variable 's2' here}}
  13   return s2; // expected-warning{{Address of stack memory associated with local variable 's1' returned}} expected-warning {{reference to stack memory associated with local variable 's1' returned}}
  14 }
  15
  16 const int& g3() {
  17   int s1;
  18   int &s2 = s1; // expected-note {{binding reference variable 's2' here}}
  19   int &s3 = s2; // expected-note {{binding reference variable 's3' here}}
  20   return s3; // expected-warning{{Address of stack memory associated with local variable 's1' returned}} expected-warning {{reference to stack memory associated with local variable 's1' returned}}
  21 }
  22
  23 void g4() {
  24   static const int &x = 3; // no warning
  25 }
  26
  27 int get_value();
  28
  29 const int &get_reference1() { return get_value(); } // expected-warning{{Address of stack memory associated with temporary object of type 'int' returned}} expected-warning {{returning reference to local temporary}}
  30
  31 const int &get_reference2() {
  32   const int &x = get_value(); // expected-note {{binding reference variable 'x' here}}
  33   return x; // expected-warning{{Address of stack memory associated with temporary object of type 'int' lifetime extended by local variable 'x' returned to caller}} expected-warning {{returning reference to local temporary}}
  34 }
  35
  36 const int &get_reference3() {
  37   const int &x1 = get_value(); // expected-note {{binding reference variable 'x1' here}}
  38   const int &x2 = x1; // expected-note {{binding reference variable 'x2' here}}
  39   return x2; // expected-warning{{Address of stack memory associated with temporary object of type 'int' lifetime extended by local variable 'x1' returned to caller}} expected-warning {{returning reference to local temporary}}
  40 }
  41
  42 int global_var;
  43 int *f1() {
  44   int &y = global_var;
  45   return &y;
  46 }
  47
  48 int *f2() {
  49   int x1;
  50   int &x2 = x1; // expected-note {{binding reference variable 'x2' here}}
  51   return &x2; // expected-warning{{Address of stack memory associated with local variable 'x1' returned}} expected-warning {{address of stack memory associated with local variable 'x1' returned}}
  52 }
  53
  54 int *f3() {
  55   int x1;
  56   int *const &x2 = &x1; // expected-note {{binding reference variable 'x2' here}}
  57   return x2; // expected-warning {{address of stack memory associated with local variable 'x1' returned}} expected-warning {{Address of stack memory associated with local variable 'x1' returned to caller}}
  58 }
  59
  60 const int *f4() {
  61   const int &x1 = get_value(); // expected-note {{binding reference variable 'x1' here}}
  62   const int &x2 = x1; // expected-note {{binding reference variable 'x2' here}}
  63   return &x2; // expected-warning{{Address of stack memory associated with temporary object of type 'int' lifetime extended by local variable 'x1' returned to caller}} expected-warning {{returning address of local temporary}}
  64 }
  65
  66 struct S {
  67   int x;
  68 };
  69
  70 int *mf() {
  71   S s1;
  72   S &s2 = s1; // expected-note {{binding reference variable 's2' here}}
  73   int &x = s2.x; // expected-note {{binding reference variable 'x' here}}
  74   return &x; // expected-warning{{Address of stack memory associated with local variable 's1' returned}} expected-warning {{address of stack memory associated with local variable 's1' returned}}
  75 }
  76
  77 void *lf() {
  78     label:
  79     void *const &x = &&label; // expected-note {{binding reference variable 'x' here}}
  80     return x; // expected-warning {{returning address of label, which is local}}
  81 }
  82
  83 template <typename T>
  84 struct TS {
  85   int *get();
  86   int *m() {
  87     int *&x = get();
  88     return x;
  89   }
  90 };
  91
  92 int* f5() {
  93   int& i = i; // expected-warning {{Assigned value is garbage or undefined}} expected-warning{{reference 'i' is not yet bound to a value when used within its own initialization}}
  94   return &i;
  95 }
  96
  97 void *radar13226577() {
  98     void *p = &p;
  99     return p; // expected-warning {{stack memory associated with local variable 'p' returned to caller}}
 100 }
 101
 102 namespace rdar13296133 {
 103   class ConvertsToBool {
 104   public:
 105     operator bool() const { return this; }
 106   };
 107
 108   class ConvertsToIntptr {
 109   public:
 110     operator intptr_t() const { return reinterpret_cast<intptr_t>(this); }
 111   };
 112
 113   class ConvertsToPointer {
 114   public:
 115     operator const void *() const { return this; }
 116   };
 117
 118   intptr_t returnAsNonLoc() {
 119     ConvertsToIntptr obj;
 120     return obj; // expected-warning{{Address of stack memory associated with local variable 'obj' returned to caller}}
 121   }
 122
 123   bool returnAsBool() {
 124     ConvertsToBool obj;
 125     return obj; // no-warning
 126   }
 127
 128   intptr_t returnAsNonLocViaPointer() {
 129     ConvertsToPointer obj;
 130     return reinterpret_cast<intptr_t>(static_cast<const void *>(obj)); // expected-warning{{Address of stack memory associated with local variable 'obj' returned to caller}}
 131   }
 132
 133   bool returnAsBoolViaPointer() {
 134     ConvertsToPointer obj;
 135     return obj; // no-warning
 136   }
 137 }
 138
 139 void write_stack_address_to(char **q) {
 140   char local;
 141   *q = &local;
 142   // expected-warning@-1 {{Address of stack memory associated with local \
 143 variable 'local' is still referred to by the stack variable 'p' upon \
 144 returning to the caller}}
 145 }
 146
 147 void test_stack() {
 148   char *p;
 149   write_stack_address_to(&p);
 150 }
 151
 152 struct C {
 153   ~C() {} // non-trivial class
 154 };
 155
 156 C make1() {
 157   C c;
 158   return c; // no-warning
 159 }
 160
 161 void test_copy_elision() {
 162   C c1 = make1();
 163 }