text: // RUN: %clang_analyze_cc1 -analyzer-checker=alpha.core.FixedAddr,alpha.core.PointerArithm,alpha.core.PointerSub,debug.ExprInspection -analyzer-store=region -verify -triple x86_64-apple-darwin9 -Wno-tautological-pointer-compare %s
  // RUN: %clang_analyze_cc1 -analyzer-checker=alpha.core.FixedAddr,alpha.core.PointerArithm,alpha.core.PointerSub,debug.ExprInspection -analyzer-store=region -verify -triple i686-apple-darwin9 -Wno-tautological-pointer-compare %s
  
  void clang_analyzer_eval(int);
  
  void f1() {
    int a[10];
    int *p = a;
    ++p;
  }
  
  char* foo();
  
  void f2() {
    char *p = foo();
    ++p;
  }
  
  // This test case checks if we get the right rvalue type of a TypedViewRegion.
  // The ElementRegion's type depends on the array region's rvalue type. If it was
  // a pointer type, we would get a loc::SymbolVal for '*p'.
  void* memchr();
  static int
  domain_port (const char *domain_b, const char *domain_e,
               const char **domain_e_ptr)
  {
    int port = 0;
    
    const char *p;
    const char *colon = memchr (domain_b, ':', domain_e - domain_b);
    
    for (p = colon + 1; p < domain_e ; p++)
      port = 10 * port + (*p - '0');
    return port;
  }
  
  void f3() {
    int x, y;
    int d = &y - &x; // expected-warning{{Subtraction of two pointers that do not point to the same memory chunk may cause incorrect result}}
  
    int a[10];
    int *p = &a[2];
    int *q = &a[8];
    d = q-p; // no-warning
  }
  
  void f4() {
    int *p;
    p = (int*) 0x10000; // expected-warning{{Using a fixed address is not portable because that address will probably not be valid in all environments or platforms}}
  }
  
  void f5() {
    int x, y;
    int *p;
    p = &x + 1;  // expected-warning{{Pointer arithmetic on non-array variables relies on memory layout, which is dangerous}}
  
    int a[10];
    p = a + 1; // no-warning
  }
  
  // Allow arithmetic on different symbolic regions.
  void f6(int *p, int *q) {
    int d = q - p; // no-warning
  }
  
  void null_operand(int *a) {
  start:
    // LHS is a label, RHS is NULL
    clang_analyzer_eval(&&start != 0); // expected-warning{{TRUE}}
    clang_analyzer_eval(&&start >= 0); // expected-warning{{TRUE}}
    clang_analyzer_eval(&&start > 0); // expected-warning{{TRUE}}
    clang_analyzer_eval((&&start - 0) != 0); // expected-warning{{TRUE}}
  
    // LHS is a non-symbolic value, RHS is NULL
    clang_analyzer_eval(&a != 0); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a >= 0); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a > 0); // expected-warning{{TRUE}}
    clang_analyzer_eval((&a - 0) != 0); // expected-warning{{TRUE}}
  
    // LHS is NULL, RHS is non-symbolic
    // The same code is used for labels and non-symbolic values.
    clang_analyzer_eval(0 != &a); // expected-warning{{TRUE}}
    clang_analyzer_eval(0 <= &a); // expected-warning{{TRUE}}
    clang_analyzer_eval(0 < &a); // expected-warning{{TRUE}}
  
    // LHS is a symbolic value, RHS is NULL
    clang_analyzer_eval(a != 0); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(a >= 0); // expected-warning{{TRUE}}
    clang_analyzer_eval(a <= 0); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval((a - 0) != 0); // expected-warning{{UNKNOWN}}
  
    // LHS is NULL, RHS is a symbolic value
    clang_analyzer_eval(0 != a); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(0 <= a); // expected-warning{{TRUE}}
    clang_analyzer_eval(0 < a); // expected-warning{{UNKNOWN}}
  }
  
  void const_locs() {
    char *a = (char*)0x1000;
    char *b = (char*)0x1100;
  start:
    clang_analyzer_eval(a != b); // expected-warning{{TRUE}}
    clang_analyzer_eval(a < b); // expected-warning{{TRUE}}
    clang_analyzer_eval(a <= b); // expected-warning{{TRUE}}
    clang_analyzer_eval((b-a) == 0x100); // expected-warning{{TRUE}}
  
    clang_analyzer_eval(&&start == a); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(a == &&start); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(&a == (char**)a); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval((char**)a == &a); // expected-warning{{UNKNOWN}}
  }
  
  void array_matching_types() {
    int array[10];
    int *a = &array[2];
    int *b = &array[5];
  
    clang_analyzer_eval(a != b); // expected-warning{{TRUE}}
    clang_analyzer_eval(a < b); // expected-warning{{TRUE}}
    clang_analyzer_eval(a <= b); // expected-warning{{TRUE}}
    clang_analyzer_eval((b-a) != 0); // expected-warning{{TRUE}}
  }
  
  // This takes a different code path than array_matching_types()
  void array_different_types() {
    int array[10];
    int *a = &array[2];
    char *b = (char*)&array[5];
  
    clang_analyzer_eval(a != b); // expected-warning{{TRUE}} expected-warning{{comparison of distinct pointer types}}
    clang_analyzer_eval(a < b); // expected-warning{{TRUE}} expected-warning{{comparison of distinct pointer types}}
    clang_analyzer_eval(a <= b); // expected-warning{{TRUE}} expected-warning{{comparison of distinct pointer types}}
  }
  
  struct test { int x; int y; };
  void struct_fields() {
    struct test a, b;
  
    clang_analyzer_eval(&a.x != &a.y); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a.x < &a.y); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a.x <= &a.y); // expected-warning{{TRUE}}
  
    clang_analyzer_eval(&a.x != &b.x); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a.x > &b.x); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(&a.x >= &b.x); // expected-warning{{UNKNOWN}}
  }
  
  void mixed_region_types() {
    struct test s;
    int array[2];
    void *a = &array, *b = &s;
  
    clang_analyzer_eval(&a != &b); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a > &b); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(&a >= &b); // expected-warning{{UNKNOWN}}
  }
  
  void symbolic_region(int *p) {
    int a;
  
    clang_analyzer_eval(&a != p); // expected-warning{{TRUE}}
    clang_analyzer_eval(&a > p); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(&a >= p); // expected-warning{{UNKNOWN}}
  }
  
  void PR7527 (int *p) {
    if (((int) p) & 1) // not crash
      return;
  }
  
  void use_symbols(int *lhs, int *rhs) {
    clang_analyzer_eval(lhs < rhs); // expected-warning{{UNKNOWN}}
    if (lhs < rhs)
      return;
    clang_analyzer_eval(lhs < rhs); // expected-warning{{FALSE}}
  
    clang_analyzer_eval(lhs - rhs); // expected-warning{{UNKNOWN}}
    if ((lhs - rhs) != 5)
      return;
    clang_analyzer_eval((lhs - rhs) == 5); // expected-warning{{TRUE}}
  }
  
  void equal_implies_zero(int *lhs, int *rhs) {
    clang_analyzer_eval(lhs == rhs); // expected-warning{{UNKNOWN}}
    if (lhs == rhs) {
      clang_analyzer_eval(lhs != rhs); // expected-warning{{FALSE}}
      clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{TRUE}}
      return;
    }
    clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
    clang_analyzer_eval(lhs != rhs); // expected-warning{{TRUE}}
    clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{FALSE}}
  }
  
  void zero_implies_equal(int *lhs, int *rhs) {
    clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{UNKNOWN}}
    if ((rhs - lhs) == 0) {
      clang_analyzer_eval(lhs != rhs); // expected-warning{{FALSE}}
      clang_analyzer_eval(lhs == rhs); // expected-warning{{TRUE}}
      return;
    }
    clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{FALSE}}
    clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
    clang_analyzer_eval(lhs != rhs); // expected-warning{{TRUE}}
  }
  
  void comparisons_imply_size(int *lhs, int *rhs) {
    clang_analyzer_eval(lhs <= rhs); // expected-warning{{UNKNOWN}}
  
    if (lhs > rhs) {
      clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{FALSE}}
      return;
    }
  
    clang_analyzer_eval(lhs <= rhs); // expected-warning{{TRUE}}
  // FIXME: In Z3ConstraintManager, ptrdiff_t is mapped to signed bitvector. However, this does not directly imply the unsigned comparison.
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval((rhs - lhs) >= 0); // expected-warning{{UNKNOWN}}
  #else
    clang_analyzer_eval((rhs - lhs) >= 0); // expected-warning{{TRUE}}
  #endif
    clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{UNKNOWN}}
  
    if (lhs >= rhs) {
      clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{TRUE}}
      return;
    }
  
    clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
    clang_analyzer_eval(lhs < rhs); // expected-warning{{TRUE}}
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{UNKNOWN}}
  #else
    clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{TRUE}}
  #endif
  }
  
  void size_implies_comparison(int *lhs, int *rhs) {
    clang_analyzer_eval(lhs <= rhs); // expected-warning{{UNKNOWN}}
  
    if ((rhs - lhs) < 0) {
      clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
      return;
    }
  
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval(lhs <= rhs); // expected-warning{{UNKNOWN}}
  #else
    clang_analyzer_eval(lhs <= rhs); // expected-warning{{TRUE}}
  #endif
    clang_analyzer_eval((rhs - lhs) >= 0); // expected-warning{{TRUE}}
    clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{UNKNOWN}}
  
    if ((rhs - lhs) <= 0) {
      clang_analyzer_eval(lhs == rhs); // expected-warning{{TRUE}}
      return;
    }
  
    clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval(lhs < rhs); // expected-warning{{UNKNOWN}}
  #else
    clang_analyzer_eval(lhs < rhs); // expected-warning{{TRUE}}
  #endif
    clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{TRUE}}
  }
  
  //-------------------------------
  // False positives
  //-------------------------------
  
  void zero_implies_reversed_equal(int *lhs, int *rhs) {
    clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{UNKNOWN}}
    if ((rhs - lhs) == 0) {
  #ifdef ANALYZER_CM_Z3
      clang_analyzer_eval(rhs != lhs); // expected-warning{{FALSE}}
      clang_analyzer_eval(rhs == lhs); // expected-warning{{TRUE}}
  #else
      clang_analyzer_eval(rhs != lhs); // expected-warning{{UNKNOWN}}
      clang_analyzer_eval(rhs == lhs); // expected-warning{{UNKNOWN}}
  #endif
      return;
    }
    clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{FALSE}}
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval(rhs == lhs); // expected-warning{{FALSE}}
    clang_analyzer_eval(rhs != lhs); // expected-warning{{TRUE}}
  #else
    clang_analyzer_eval(rhs == lhs); // expected-warning{{UNKNOWN}}
    clang_analyzer_eval(rhs != lhs); // expected-warning{{UNKNOWN}}
  #endif
  }
  
  void canonical_equal(int *lhs, int *rhs) {
    clang_analyzer_eval(lhs == rhs); // expected-warning{{UNKNOWN}}
    if (lhs == rhs) {
  #ifdef ANALYZER_CM_Z3
      clang_analyzer_eval(rhs == lhs); // expected-warning{{TRUE}}
  #else
      clang_analyzer_eval(rhs == lhs); // expected-warning{{UNKNOWN}}
  #endif
      return;
    }
    clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}}
  
  #ifdef ANALYZER_CM_Z3
    clang_analyzer_eval(rhs == lhs); // expected-warning{{FALSE}}
  #else
    clang_analyzer_eval(rhs == lhs); // expected-warning{{UNKNOWN}}
  #endif
  }
  
  void compare_element_region_and_base(int *p) {
    int *q = p - 1;
    clang_analyzer_eval(p == q); // expected-warning{{FALSE}}
  }
  
  struct Point {
    int x;
    int y;
  };
  void symbolicFieldRegion(struct Point *points, int i, int j) {
    clang_analyzer_eval(&points[i].x == &points[j].x);// expected-warning{{UNKNOWN}}
    clang_analyzer_eval(&points[i].x == &points[i].y);// expected-warning{{FALSE}}
    clang_analyzer_eval(&points[i].x < &points[i].y);// expected-warning{{TRUE}}
  }
  
  void negativeIndex(char *str) {
    *(str + 1) = 'a';
    clang_analyzer_eval(*(str + 1) == 'a'); // expected-warning{{TRUE}}
    clang_analyzer_eval(*(str - 1) == 'a'); // expected-warning{{UNKNOWN}}
  
    char *ptr1 = str - 1;
    clang_analyzer_eval(*ptr1 == 'a'); // expected-warning{{UNKNOWN}}
  
    char *ptr2 = str;
    ptr2 -= 1;
    clang_analyzer_eval(*ptr2 == 'a'); // expected-warning{{UNKNOWN}}
  
    char *ptr3 = str;
    --ptr3;
    clang_analyzer_eval(*ptr3 == 'a'); // expected-warning{{UNKNOWN}}
  }
  
  