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
| // RUN: %clang_analyze_cc1 \
// RUN: -analyzer-checker=core,apiModeling.llvm.ReturnValue \
// RUN: -analyzer-output=text -verify=class %s
struct Foo { int Field; };
bool problem();
void doSomething();
// We predefined the return value of 'MCAsmParser::Error' as true and we cannot
// take the false-branches which leads to a "garbage value" false positive.
namespace test_classes {
struct MCAsmParser {
static bool Error();
};
bool parseFoo(Foo &F) {
if (problem()) {
// class-note@-1 {{Assuming the condition is false}}
// class-note@-2 {{Taking false branch}}
return MCAsmParser::Error();
}
F.Field = 0;
// class-note@-1 {{The value 0 is assigned to 'F.Field'}}
return !MCAsmParser::Error();
// class-note@-1 {{'MCAsmParser::Error' returns true}}
// class-note@-2 {{Returning zero, which participates in a condition later}}
}
bool parseFile() {
Foo F;
if (parseFoo(F)) {
// class-note@-1 {{Calling 'parseFoo'}}
// class-note@-2 {{Returning from 'parseFoo'}}
// class-note@-3 {{Taking false branch}}
return true;
}
if (F.Field == 0) {
// class-note@-1 {{Field 'Field' is equal to 0}}
// class-note@-2 {{Taking true branch}}
// no-warning: "The left operand of '==' is a garbage value" was here.
doSomething();
}
(void)(1 / F.Field);
// class-warning@-1 {{Division by zero}}
// class-note@-2 {{Division by zero}}
return false;
}
} // namespace test_classes
// We predefined 'MCAsmParser::Error' as returning true, but now it returns
// false, which breaks our invariant. Test the notes.
namespace test_break {
struct MCAsmParser {
static bool Error() {
return false; // class-note {{'MCAsmParser::Error' returns false}}
// class-note@-1 {{Returning zero, which participates in a condition later}}
}
};
bool parseFoo(Foo &F) {
if (problem()) {
// class-note@-1 {{Assuming the condition is false}}
// class-note@-2 {{Taking false branch}}
return !MCAsmParser::Error();
}
F.Field = 0;
// class-note@-1 {{The value 0 is assigned to 'F.Field'}}
return MCAsmParser::Error();
// class-note@-1 {{Calling 'MCAsmParser::Error'}}
// class-note@-2 {{Returning from 'MCAsmParser::Error'}}
// class-note@-3 {{Returning zero, which participates in a condition later}}
}
bool parseFile() {
Foo F;
if (parseFoo(F)) {
// class-note@-1 {{Calling 'parseFoo'}}
// class-note@-2 {{Returning from 'parseFoo'}}
// class-note@-3 {{Taking false branch}}
return true;
}
(void)(1 / F.Field);
// class-warning@-1 {{Division by zero}}
// class-note@-2 {{Division by zero}}
return false;
}
} // namespace test_classes
|