blob: da14f4c010d6216077eb7a2322df212352110c5b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
// RUN: %clang_cc1 -analyze -analyzer-checker=core,deadcode.DeadStores,experimental.deadcode.UnreachableCode -verify -analyzer-opt-analyze-nested-blocks -Wno-unused-value %s
extern void foo(int a);
// The first few tests are non-path specific - we should be able to find them
void test(unsigned a) {
switch (a) {
a += 5; // expected-warning{{never executed}}
case 2:
a *= 10;
case 3:
a %= 2;
}
foo(a);
}
void test2(unsigned a) {
help:
if (a > 0)
return;
if (a == 0)
return;
foo(a); // expected-warning{{never executed}}
goto help;
}
void test3(unsigned a) {
while(1);
if (a > 5) { // expected-warning{{never executed}}
return;
}
}
// These next tests are path-sensitive
void test4() {
int a = 5;
while (a > 1)
a -= 2;
if (a > 1) {
a = a + 56; // expected-warning{{never executed}}
}
foo(a);
}
extern void bar(char c);
void test5(const char *c) {
foo(c[0]);
if (!c) {
bar(1); // expected-warning{{never executed}}
}
}
// These next tests are false positives and should not generate warnings
void test6(const char *c) {
if (c) return;
if (!c) return;
__builtin_unreachable(); // no-warning
}
// Compile-time constant false positives
#define CONSTANT 0
enum test_enum { Off, On };
void test7() {
if (CONSTANT)
return; // no-warning
if (sizeof(int))
return; // no-warning
if (Off)
return; // no-warning
}
void test8() {
static unsigned a = 0;
if (a)
a = 123; // no-warning
a = 5;
}
// Check for bugs where multiple statements are reported
void test9(unsigned a) {
switch (a) {
if (a) // expected-warning{{never executed}}
foo(a + 5); // no-warning
else // no-warning
foo(a); // no-warning
case 1:
case 2:
break;
default:
break;
}
}
// Tests from flow-sensitive version
void test10() {
goto c;
d:
goto e; // expected-warning {{never executed}}
c: ;
int i;
return;
goto b; // expected-warning {{never executed}}
goto a; // expected-warning {{never executed}}
b:
i = 1; // no-warning
a:
i = 2; // no-warning
goto f;
e:
goto d;
f: ;
}
|
