clang/test/Analysis/call-invalidation.cpp

   1 // RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify -analyzer-config eagerly-assume=false %s
   2
   3 void clang_analyzer_eval(bool);
   4
   5 void usePointer(int * const *);
   6 void useReference(int * const &);
   7
   8 void testPointer() {
   9   int x;
  10   int *p;
  11
  12   p = &x;
  13   x = 42;
  14   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  15   usePointer(&p);
  16   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  17
  18   p = &x;
  19   x = 42;
  20   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  21   useReference(p);
  22   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  23
  24   int * const cp1 = &x;
  25   x = 42;
  26   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  27   usePointer(&cp1);
  28   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  29
  30   int * const cp2 = &x;
  31   x = 42;
  32   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  33   useReference(cp2);
  34   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  35 }
  36
  37
  38 struct Wrapper {
  39   int *ptr;
  40 };
  41
  42 void useStruct(Wrapper &w);
  43 void useConstStruct(const Wrapper &w);
  44
  45 void testPointerStruct() {
  46   int x;
  47   Wrapper w;
  48
  49   w.ptr = &x;
  50   x = 42;
  51   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  52   useStruct(w);
  53   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  54
  55   w.ptr = &x;
  56   x = 42;
  57   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  58   useConstStruct(w);
  59   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  60 }
  61
  62
  63 struct RefWrapper {
  64   int &ref;
  65 };
  66
  67 void useStruct(RefWrapper &w);
  68 void useConstStruct(const RefWrapper &w);
  69
  70 void testReferenceStruct() {
  71   int x;
  72   RefWrapper w = { x };
  73
  74   x = 42;
  75   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  76   useStruct(w);
  77   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  78 }
  79
  80 // FIXME: This test is split into two functions because region invalidation
  81 // does not preserve reference bindings.
  82 void testConstReferenceStruct() {
  83   int x;
  84   RefWrapper w = { x };
  85
  86   x = 42;
  87   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
  88   useConstStruct(w);
  89   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
  90 }
  91
  92
  93 void usePointerPure(int * const *) __attribute__((pure));
  94 void usePointerConst(int * const *) __attribute__((const));
  95
  96 void testPureConst() {
  97   extern int global;
  98   int x;
  99   int *p;
 100
 101   p = &x;
 102   x = 42;
 103   global = -5;
 104   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
 105   clang_analyzer_eval(global == -5); // expected-warning{{TRUE}}
 106
 107   usePointerPure(&p);
 108   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
 109   clang_analyzer_eval(global == -5); // expected-warning{{TRUE}}
 110
 111   usePointerConst(&p);
 112   clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
 113   clang_analyzer_eval(global == -5); // expected-warning{{TRUE}}
 114
 115   usePointer(&p);
 116   clang_analyzer_eval(x == 42); // expected-warning{{UNKNOWN}}
 117   clang_analyzer_eval(global == -5); // expected-warning{{UNKNOWN}}
 118 }
 119
 120
 121 struct PlainStruct {
 122   int x, y;
 123   mutable int z;
 124 };
 125
 126 PlainStruct glob;
 127
 128 void useAnything(void *);
 129 void useAnythingConst(const void *);
 130
 131 void testInvalidationThroughBaseRegionPointer() {
 132   PlainStruct s1;
 133   s1.x = 1;
 134   s1.z = 1;
 135   clang_analyzer_eval(s1.x == 1); // expected-warning{{TRUE}}
 136   clang_analyzer_eval(s1.z == 1); // expected-warning{{TRUE}}
 137   // Not only passing a structure pointer through const pointer parameter,
 138   // but also passing a field pointer through const pointer parameter
 139   // should preserve the contents of the structure.
 140   useAnythingConst(&(s1.y));
 141   clang_analyzer_eval(s1.x == 1); // expected-warning{{TRUE}}
 142   // FIXME: Should say "UNKNOWN", because it is not uncommon to
 143   // modify a mutable member variable through const pointer.
 144   clang_analyzer_eval(s1.z == 1); // expected-warning{{TRUE}}
 145   useAnything(&(s1.y));
 146   clang_analyzer_eval(s1.x == 1); // expected-warning{{UNKNOWN}}
 147 }
 148
 149
 150 void useFirstConstSecondNonConst(const void *x, void *y);
 151 void useFirstNonConstSecondConst(void *x, const void *y);
 152
 153 void testMixedConstNonConstCalls() {
 154   PlainStruct s2;
 155   s2.x = 1;
 156   useFirstConstSecondNonConst(&(s2.x), &(s2.y));
 157   clang_analyzer_eval(s2.x == 1); // expected-warning{{UNKNOWN}}
 158   s2.x = 1;
 159   useFirstNonConstSecondConst(&(s2.x), &(s2.y));
 160   clang_analyzer_eval(s2.x == 1); // expected-warning{{UNKNOWN}}
 161   s2.y = 1;
 162   useFirstConstSecondNonConst(&(s2.x), &(s2.y));
 163   clang_analyzer_eval(s2.y == 1); // expected-warning{{UNKNOWN}}
 164   s2.y = 1;
 165   useFirstNonConstSecondConst(&(s2.x), &(s2.y));
 166   clang_analyzer_eval(s2.y == 1); // expected-warning{{UNKNOWN}}
 167 }