clang/test/Analysis/division-by-zero-track-zero.cpp

   1 // RUN: %clang_analyze_cc1 -analyzer-checker=core \
   2 // RUN:   -analyzer-output=text \
   3 // RUN:   -verify %s
   4
   5 namespace test_tracking_of_lhs_multiplier {
   6   int f(int x, int y) {
   7     bool p0 = x < 0;  // expected-note {{Assuming 'x' is >= 0}} \
   8                       // expected-note {{'p0' initialized to 0}}
   9     int div = p0 * y; // expected-note {{'div' initialized to 0}}
  10     return 1 / div;   // expected-note {{Division by zero}} \
  11                       // expected-warning {{Division by zero}}
  12   }
  13 } // namespace test_tracking_of_lhs_multiplier
  14
  15 namespace test_tracking_of_rhs_multiplier {
  16   int f(int x, int y) {
  17     bool p0 = x < 0;  // expected-note {{Assuming 'x' is >= 0}} \
  18                       // expected-note {{'p0' initialized to 0}}
  19     int div = y * p0; // expected-note {{'div' initialized to 0}}
  20     return 1 / div;   // expected-note {{Division by zero}} \
  21                       // expected-warning {{Division by zero}}
  22   }
  23 } // namespace test_tracking_of_rhs_multiplier
  24
  25 namespace test_tracking_of_nested_multiplier {
  26   int f(int x, int y, int z) {
  27     bool p0 = x < 0;  // expected-note {{Assuming 'x' is >= 0}} \
  28                       // expected-note {{'p0' initialized to 0}}
  29     int div = y*z*p0; // expected-note {{'div' initialized to 0}}
  30     return 1 / div;   // expected-note {{Division by zero}} \
  31                       // expected-warning {{Division by zero}}
  32   }
  33 } // namespace test_tracking_of_nested_multiplier
  34
  35 namespace test_tracking_through_multiple_stmts {
  36   int f(int x, int y) {
  37     bool p0 = x < 0;      // expected-note {{Assuming 'x' is >= 0}}
  38     bool p1 = p0 ? 0 : 1; // expected-note {{'p0' is false}} \
  39                           // expected-note {{'?' condition is false}}
  40     bool p2 = 1 - p1;     // expected-note {{'p2' initialized to 0}}
  41     int div = p2 * y;     // expected-note {{'div' initialized to 0}}
  42     return 1 / div;       // expected-note {{Division by zero}} \
  43                           // expected-warning {{Division by zero}}
  44   }
  45 } // namespace test_tracking_through_multiple_stmts
  46
  47 namespace test_tracking_both_lhs_and_rhs {
  48   int f(int x, int y) {
  49     bool p0 = x < 0;   // expected-note {{Assuming 'x' is >= 0}} \
  50                        // expected-note {{'p0' initialized to 0}}
  51     bool p1 = y < 0;   // expected-note {{Assuming 'y' is >= 0}} \
  52                        // expected-note {{'p1' initialized to 0}}
  53     int div = p0 * p1; // expected-note {{'div' initialized to 0}}
  54     return 1 / div;    // expected-note {{Division by zero}} \
  55                        // expected-warning {{Division by zero}}
  56   }
  57 } // namespace test_tracking_both_lhs_and_rhs
  58
  59 namespace test_tracking_of_multiplier_and_parens {
  60   int f(int x, int y, int z) {
  61     bool p0 = x < 0;    // expected-note {{Assuming 'x' is >= 0}} \
  62                         // expected-note {{'p0' initialized to 0}}
  63     int div = y*(z*p0); // expected-note {{'div' initialized to 0}}
  64     return 1 / div;     // expected-note {{Division by zero}} \
  65                         // expected-warning {{Division by zero}}
  66   }
  67 } // namespace test_tracking_of_multiplier_and_parens
  68
  69 namespace test_tracking_of_divisible {
  70   int f(int x, int y) {
  71     bool p0 = x < 0;    // expected-note {{Assuming 'x' is >= 0}} \
  72                         // expected-note {{'p0' initialized to 0}}
  73     int div = p0 / y;   // expected-note {{'div' initialized to 0}}
  74     return 1 / div;     // expected-note {{Division by zero}} \
  75                         // expected-warning {{Division by zero}}
  76   }
  77 } // namespace test_tracking_of_divisible
  78
  79 namespace test_tracking_of_modulo {
  80   int f(int x, int y) {
  81     bool p0 = x < 0;    // expected-note {{Assuming 'x' is >= 0}} \
  82                         // expected-note {{'p0' initialized to 0}}
  83     int div = p0 % y;   // expected-note {{'div' initialized to 0}}
  84     return 1 / div;     // expected-note {{Division by zero}} \
  85                         // expected-warning {{Division by zero}}
  86   }
  87 } // namespace test_tracking_of_modulo
  88
  89 namespace test_tracking_of_assignment {
  90   int f(int x) {
  91     bool p0 = x < 0;    // expected-note {{Assuming 'x' is >= 0}} \
  92                         // expected-note {{'p0' initialized to 0}}
  93     int div = 1;
  94     div *= p0;          // expected-note {{The value 0 is assigned to 'div'}}
  95     return 1 / div;     // expected-note {{Division by zero}} \
  96                         // expected-warning {{Division by zero}}
  97   }
  98 } // namespace test_tracking_of_assignment