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
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
| // RUN: %clang_cc1 -fsyntax-only -verify %s
// RUN: %clang_cc1 -fsyntax-only -verify -std=c++98 %s
// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
namespace BooleanFalse {
int* j = false;
#if __cplusplus <= 199711L
// expected-warning@-2 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@-4 {{cannot initialize a variable of type 'int *' with an rvalue of type 'bool'}}
#endif
#if __cplusplus <= 199711L
// expected-warning@+6 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@+4 {{cannot initialize a parameter of type 'int *' with an rvalue of type 'bool'}}
// expected-note@+3 {{passing argument to parameter 'j' here}}
// expected-note@+2 6 {{candidate function not viable: requires 2 arguments, but 1 was provided}}
#endif
void foo(int* i, int *j=(false))
{
foo(false);
#if __cplusplus <= 199711L
// expected-warning@-2 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
foo((int*)false);
#if __cplusplus <= 199711L
// no-warning: explicit cast
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
foo(0);
#if __cplusplus <= 199711L
// no-warning: not a bool, even though its convertible to bool
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
foo(false == true);
#if __cplusplus <= 199711L
// expected-warning@-2 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
foo((42 + 24) < 32);
#if __cplusplus <= 199711L
// expected-warning@-2 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
const bool kFlag = false;
foo(kFlag);
#if __cplusplus <= 199711L
// expected-warning@-2 {{initialization of pointer of type 'int *' to null from a constant boolean expression}}
#else
// expected-error@-4 {{no matching function for call to 'foo'}}
#endif
}
char f(struct Undefined*);
double f(...);
// Ensure that when using false in metaprogramming machinery its conversion
// isn't flagged.
template <int N> struct S {};
S<sizeof(f(false))> s;
}
namespace Function {
void f1();
struct S {
static void f2();
};
extern void f3() __attribute__((weak_import));
struct S2 {
static void f4() __attribute__((weak_import));
};
bool f5();
bool f6(int);
void bar() {
bool b;
b = f1; // expected-warning {{address of function 'f1' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
if (f1) {} // expected-warning {{address of function 'f1' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
b = S::f2; // expected-warning {{address of function 'S::f2' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
if (S::f2) {} // expected-warning {{address of function 'S::f2' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
b = f5; // expected-warning {{address of function 'f5' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}} \
expected-note {{suffix with parentheses to turn this into a function call}}
b = f6; // expected-warning {{address of function 'f6' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
// implicit casts of weakly imported symbols are ok:
b = f3;
if (f3) {}
b = S2::f4;
if (S2::f4) {}
}
}
namespace Array {
#define GetValue(ptr) ((ptr) ? ptr[0] : 0)
extern int a[] __attribute__((weak));
int b[] = {8,13,21};
struct {
int x[10];
} c;
const char str[] = "text";
void ignore() {
if (a) {}
if (a) {}
(void)GetValue(b);
}
void test() {
if (b) {}
// expected-warning@-1{{address of array 'b' will always evaluate to 'true'}}
if (b) {}
// expected-warning@-1{{address of array 'b' will always evaluate to 'true'}}
if (c.x) {}
// expected-warning@-1{{address of array 'c.x' will always evaluate to 'true'}}
if (str) {}
// expected-warning@-1{{address of array 'str' will always evaluate to 'true'}}
}
}
namespace Pointer {
extern int a __attribute__((weak));
int b;
static int c;
class S {
public:
static int a;
int b;
};
void ignored() {
if (&a) {}
}
void test() {
S s;
if (&b) {}
// expected-warning@-1{{address of 'b' will always evaluate to 'true'}}
if (&c) {}
// expected-warning@-1{{address of 'c' will always evaluate to 'true'}}
if (&s.a) {}
// expected-warning@-1{{address of 's.a' will always evaluate to 'true'}}
if (&s.b) {}
// expected-warning@-1{{address of 's.b' will always evaluate to 'true'}}
if (&S::a) {}
// expected-warning@-1{{address of 'S::a' will always evaluate to 'true'}}
}
}
namespace macros {
#define assert(x) if (x) {}
#define zero_on_null(x) ((x) ? *(x) : 0)
int array[5];
void fun();
int x;
void test() {
assert(array);
assert(array && "expecting null pointer");
// expected-warning@-1{{address of array 'array' will always evaluate to 'true'}}
assert(fun);
assert(fun && "expecting null pointer");
// expected-warning@-1{{address of function 'fun' will always evaluate to 'true'}}
// expected-note@-2 {{prefix with the address-of operator to silence this warning}}
// TODO: warn on assert(&x) while not warning on zero_on_null(&x)
zero_on_null(&x);
assert(zero_on_null(&x));
assert(&x);
assert(&x && "expecting null pointer");
// expected-warning@-1{{address of 'x' will always evaluate to 'true'}}
}
}
|