clang/test/Analysis/builtin-functions.cpp

   1 // RUN: %clang_analyze_cc1 -triple x86_64-apple-darwin10 -analyzer-checker=core,debug.ExprInspection %s -std=c++11 -verify
   2
   3 void clang_analyzer_eval(bool);
   4 void clang_analyzer_warnIfReached();
   5
   6 void testAddressof(int x) {
   7   clang_analyzer_eval(&x == __builtin_addressof(x)); // expected-warning{{TRUE}}
   8 }
   9
  10 void testSize() {
  11   struct {
  12     int x;
  13     int y;
  14     char z;
  15   } object;
  16   clang_analyzer_eval(__builtin_object_size(&object.y, 0) == sizeof(object) - sizeof(int)); // expected-warning{{TRUE}}
  17
  18   // Clang can't actually evaluate these builtin "calls", but importantly they don't actually evaluate the argument expression either.
  19   int i = 0;
  20   char buf[10];
  21   clang_analyzer_eval(__builtin_object_size(&buf[i++], 0) == sizeof(buf)); // expected-warning{{FALSE}}
  22   clang_analyzer_eval(__builtin_object_size(&buf[++i], 0) == sizeof(buf) - 1); // expected-warning{{FALSE}}
  23
  24   clang_analyzer_eval(i == 0); // expected-warning{{TRUE}}
  25 }
  26
  27 void test_assume_aligned_1(char *p) {
  28   char *q;
  29
  30   q = (char*) __builtin_assume_aligned(p, 16);
  31   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
  32 }
  33
  34 void test_assume_aligned_2(char *p) {
  35   char *q;
  36
  37   q = (char*) __builtin_assume_aligned(p, 16, 8);
  38   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
  39 }
  40
  41 void test_assume_aligned_3(char *p) {
  42   void *q;
  43
  44   q = __builtin_assume_aligned(p, 16, 8);
  45   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
  46 }
  47
  48 void test_assume_aligned_4(char *p) {
  49   char *q;
  50
  51   q = (char*) __builtin_assume_aligned(p + 1, 16);
  52   clang_analyzer_eval(p == q); // expected-warning{{FALSE}}
  53 }
  54
  55 void f(int i) {
  56   __builtin_assume(i < 10);
  57   clang_analyzer_eval(i < 15); // expected-warning {{TRUE}}
  58 }
  59
  60 void g(int i) {
  61   if (i > 5) {
  62     __builtin_assume(i < 5);
  63     clang_analyzer_warnIfReached(); // Assumtion contradicts constraints.
  64                                     // We give up the analysis on this path.
  65   }
  66 }
  67
  68 void test_constant_p(void *ptr) {
  69   int i = 1;
  70   const int j = 2;
  71   constexpr int k = 3;
  72   clang_analyzer_eval(__builtin_constant_p(42) == 1); // expected-warning {{TRUE}}
  73   clang_analyzer_eval(__builtin_constant_p(i) == 0); // expected-warning {{TRUE}}
  74   clang_analyzer_eval(__builtin_constant_p(j) == 1); // expected-warning {{TRUE}}
  75   clang_analyzer_eval(__builtin_constant_p(k) == 1); // expected-warning {{TRUE}}
  76   clang_analyzer_eval(__builtin_constant_p(i + 42) == 0); // expected-warning {{TRUE}}
  77   clang_analyzer_eval(__builtin_constant_p(j + 42) == 1); // expected-warning {{TRUE}}
  78   clang_analyzer_eval(__builtin_constant_p(k + 42) == 1); // expected-warning {{TRUE}}
  79   clang_analyzer_eval(__builtin_constant_p(" ") == 1); // expected-warning {{TRUE}}
  80   clang_analyzer_eval(__builtin_constant_p(test_constant_p) == 0); // expected-warning {{TRUE}}
  81   clang_analyzer_eval(__builtin_constant_p(k - 3) == 0); // expected-warning {{FALSE}}
  82   clang_analyzer_eval(__builtin_constant_p(k - 3) == 1); // expected-warning {{TRUE}}
  83   clang_analyzer_eval(__builtin_constant_p(ptr == 0)); // expected-warning {{FALSE}}
  84 }