global-region-invalidation.c revision 262e0d41e49c6b823d62743535e2accb117a6ea9 
1// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -analyze -disable-free -analyzer-eagerly-assume -analyzer-checker=core,deadcode,alpha.security.taint,debug.TaintTest,debug.ExprInspection -verify %s
2
3void clang_analyzer_eval(int);
4
5// Note, we do need to include headers here, since the analyzer checks if the function declaration is located in a system header.
6#include "Inputs/system-header-simulator.h"
7
8// Test that system header does not invalidate the internal global.
9int size_rdar9373039 = 1;
10int rdar9373039() {
11  int x;
12  int j = 0;
13
14  for (int i = 0 ; i < size_rdar9373039 ; ++i)
15    x = 1;
16
17  // strlen doesn't invalidate the value of 'size_rdar9373039'.
18  int extra = (2 + strlen ("Clang") + ((4 - ((unsigned int) (2 + strlen ("Clang")) % 4)) % 4)) + (2 + strlen ("1.0") + ((4 - ((unsigned int) (2 + strlen ("1.0")) % 4)) % 4));
19
20  for (int i = 0 ; i < size_rdar9373039 ; ++i)
21    j += x; // no-warning
22
23  return j;
24}
25
26// Test stdin does not get invalidated by a system call nor by an internal call.
27void foo();
28int stdinTest() {
29  int i = 0;
30  fscanf(stdin, "%d", &i);
31  foo();
32  int m = i; // expected-warning + {{tainted}}
33  fscanf(stdin, "%d", &i);
34  int j = i; // expected-warning + {{tainted}}
35  return m + j; // expected-warning + {{tainted}}
36}
37
38// Test errno gets invalidated by a system call.
39int testErrnoSystem() {
40  int i;
41  int *p = 0;
42  fscanf(stdin, "%d", &i);
43  if (errno == 0) {
44    fscanf(stdin, "%d", &i); // errno gets invalidated here.
45    return 5 / errno; // no-warning
46  }
47
48  errno = 0;
49  fscanf(stdin, "%d", &i); // errno gets invalidated here.
50  return 5 / errno; // no-warning
51}
52
53// Test that errno gets invalidated by internal calls.
54int testErrnoInternal() {
55  int i;
56  int *p = 0;
57  fscanf(stdin, "%d", &i);
58  if (errno == 0) {
59    foo(); // errno gets invalidated here.
60    return 5 / errno; // no-warning
61  }
62  return 0;
63}
64
65// Test that const integer does not get invalidated.
66const int x = 0;
67int constIntGlob() {
68  const int *m = &x;
69    foo();
70  return 3 / *m; // expected-warning {{Division by zero}}
71}
72
73extern const int y;
74int constIntGlobExtern() {
75  if (y == 0) {
76    foo();
77    return 5 / y; // expected-warning {{Division by zero}}
78  }
79  return 0;
80}
81
82static void * const ptr = 0;
83void constPtrGlob() {
84  clang_analyzer_eval(ptr == 0); // expected-warning{{TRUE}}
85  foo();
86  clang_analyzer_eval(ptr == 0); // expected-warning{{TRUE}}
87}
88
89static const int x2 = x;
90void constIntGlob2() {
91  clang_analyzer_eval(x2 == 0); // expected-warning{{TRUE}}
92  foo();
93  clang_analyzer_eval(x2 == 0); // expected-warning{{TRUE}}
94}
95
96void testAnalyzerEvalIsPure() {
97  extern int someGlobal;
98  if (someGlobal == 0) {
99    clang_analyzer_eval(someGlobal == 0); // expected-warning{{TRUE}}
100    clang_analyzer_eval(someGlobal == 0); // expected-warning{{TRUE}}
101  }
102}
103
104// Test that static variables with initializers do not get reinitialized on
105// recursive calls.
106void Function2(void);
107int *getPtr();
108void Function1(void) {
109  static unsigned flag;
110  static int *p = 0;
111  if (!flag) {
112    flag = 1;
113    p = getPtr();
114  }
115  int m = *p; // no-warning: p is never null.
116  m++;
117  Function2();
118}
119void Function2(void) {
120    Function1();
121}
122
123void SetToNonZero(void) {
124  static int g = 5;
125  clang_analyzer_eval(g == 5); // expected-warning{{TRUE}}
126}
127
128