global-region-invalidation.c revision 38f68ef19cb51d5876e9025b5fceb44b33ec9ed7 
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  return 0;
48}
49
50// Test that errno gets invalidated by internal calls.
51int testErrnoInternal() {
52  int i;
53  int *p = 0;
54  fscanf(stdin, "%d", &i);
55  if (errno == 0) {
56    foo(); // errno gets invalidated here.
57    return 5 / errno; // no-warning
58  }
59  return 0;
60}
61
62// Test that const integer does not get invalidated.
63const int x = 0;
64int constIntGlob() {
65  const int *m = &x;
66    foo();
67  return 3 / *m; // expected-warning {{Division by zero}}
68}
69
70extern const int y;
71int constIntGlobExtern() {
72  if (y == 0) {
73    foo();
74    return 5 / y; // expected-warning {{Division by zero}}
75  }
76  return 0;
77}
78
79static void * const ptr = 0;
80void constPtrGlob() {
81  clang_analyzer_eval(ptr == 0); // expected-warning{{TRUE}}
82  foo();
83  clang_analyzer_eval(ptr == 0); // expected-warning{{TRUE}}
84}
85
86static const int x2 = x;
87void constIntGlob2() {
88  clang_analyzer_eval(x2 == 0); // expected-warning{{TRUE}}
89  foo();
90  clang_analyzer_eval(x2 == 0); // expected-warning{{TRUE}}
91}
92
93void testAnalyzerEvalIsPure() {
94  extern int someGlobal;
95  if (someGlobal == 0) {
96    clang_analyzer_eval(someGlobal == 0); // expected-warning{{TRUE}}
97    clang_analyzer_eval(someGlobal == 0); // expected-warning{{TRUE}}
98  }
99}
100
101// Test that static variables with initializers do not get reinitialized on
102// recursive calls.
103void Function2(void);
104int *getPtr();
105void Function1(void) {
106  static unsigned flag;
107  static int *p = 0;
108  if (!flag) {
109    flag = 1;
110    p = getPtr();
111  }
112  int m = *p; // no-warning: p is never null.
113  m++;
114  Function2();
115}
116void Function2(void) {
117    Function1();
118}
119
120void SetToNonZero(void) {
121  static int g = 5;
122  clang_analyzer_eval(g == 5); // expected-warning{{TRUE}}
123}
124
125