clang/test/Analysis/casts.cpp

   1 // RUN: %clang_analyze_cc1 -std=c++14 -analyzer-checker=core,debug.ExprInspection -verify %s
   2
   3 void clang_analyzer_eval(bool);
   4
   5 bool PR14634(int x) {
   6   double y = (double)x;
   7   return !y;
   8 }
   9
  10 bool PR14634_implicit(int x) {
  11   double y = (double)x;
  12   return y;
  13 }
  14
  15 void intAsBoolAsSwitchCondition(int c) {
  16   switch ((bool)c) { // expected-warning {{switch condition has boolean value}}
  17   case 0:
  18     break;
  19   }
  20
  21   switch ((int)(bool)c) { // no-warning
  22     case 0:
  23       break;
  24   }
  25 }
  26
  27 int *&castToIntPtrLValueRef(char *p) {
  28   return (int *&)*(int *)p;
  29 }
  30 bool testCastToIntPtrLValueRef(char *p, int *s) {
  31   return castToIntPtrLValueRef(p) != s; // no-crash
  32 }
  33
  34 int *&&castToIntPtrRValueRef(char *p) {
  35   return (int *&&)*(int *)p;
  36 }
  37 bool testCastToIntPtrRValueRef(char *p, int *s) {
  38   return castToIntPtrRValueRef(p) != s; // no-crash
  39 }
  40
  41 bool retrievePointerFromBoolean(int *p) {
  42   bool q;
  43   *reinterpret_cast<int **>(&q) = p;
  44   return q;
  45 }
  46
  47 namespace base_to_derived {
  48 struct A {};
  49 struct B : public A{};
  50
  51 void foo(A* a) {
  52   B* b = (B* ) a;
  53   A* a2 = (A *) b;
  54   clang_analyzer_eval(a2 == a); // expected-warning{{TRUE}}
  55 }
  56 }
  57
  58 namespace base_to_derived_double_inheritance {
  59 struct A {
  60   int x;
  61 };
  62 struct B {
  63   int y;
  64 };
  65 struct C : A, B {};
  66
  67 void foo(B *b) {
  68   C *c = (C *)b;
  69   b->y = 1;
  70   clang_analyzer_eval(c->x); // expected-warning{{UNKNOWN}}
  71   clang_analyzer_eval(c->y); // expected-warning{{TRUE}}
  72 }
  73 } // namespace base_to_derived_double_inheritance
  74
  75 namespace base_to_derived_opaque_class {
  76 class NotInt {
  77 public:
  78   operator int() { return !x; } // no-crash
  79   int x;
  80 };
  81
  82 typedef struct Opaque *OpaqueRef;
  83 typedef void *VeryOpaqueRef;
  84
  85 class Transparent {
  86 public:
  87   int getNotInt() { return NI; }
  88   NotInt NI;
  89 };
  90
  91 class SubTransparent : public Transparent {};
  92
  93 SubTransparent *castToDerived(Transparent *TRef) {
  94   return (SubTransparent *)TRef;
  95 }
  96
  97 void foo(OpaqueRef ORef) {
  98   castToDerived(reinterpret_cast<Transparent *>(ORef))->getNotInt();
  99 }
 100
 101 void foo(VeryOpaqueRef ORef) {
 102   castToDerived(reinterpret_cast<Transparent *>(ORef))->getNotInt();
 103 }
 104 } // namespace base_to_derived_opaque_class
 105
 106 namespace bool_to_nullptr {
 107 struct S {
 108   int *a[1];
 109   bool b;
 110 };
 111 void foo(S s) {
 112   s.b = true;
 113   for (int i = 0; i < 2; ++i)
 114     (void)(s.a[i] != nullptr); // no-crash
 115 }
 116 } // namespace bool_to_nullptr