varargs.cpp
1.75 KB
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
// RUN: %clang_cc1 -std=c++03 -verify %s
// RUN: %clang_cc1 -std=c++11 -verify %s
__builtin_va_list ap;
class string;
void f(const string& s, ...) { // expected-note {{parameter of type 'const string &' is declared here}}
__builtin_va_start(ap, s); // expected-warning {{passing an object of reference type to 'va_start' has undefined behavior}}
}
void g(register int i, ...) { // expected-warning 0-1{{deprecated}}
__builtin_va_start(ap, i); // UB in C, OK in C++
}
// Don't crash when there is no last parameter.
void no_params(...) {
int a;
__builtin_va_start(ap, a); // expected-warning {{second argument to 'va_start' is not the last named parameter}}
}
// Reject this. The __builtin_va_start would execute in Foo's non-variadic
// default ctor.
void record_context(int a, ...) {
struct Foo {
// expected-error@+1 {{'va_start' cannot be used outside a function}}
void meth(int a, int b = (__builtin_va_start(ap, a), 0)) {}
};
}
#if __cplusplus >= 201103L
// We used to have bugs identifying the correct enclosing function scope in a
// lambda.
void fixed_lambda_varargs_function(int a, ...) {
[](int b) {
__builtin_va_start(ap, b); // expected-error {{'va_start' used in function with fixed args}}
}(42);
}
void varargs_lambda_fixed_function(int a) {
[](int b, ...) {
__builtin_va_start(ap, b); // correct
}(42);
}
auto fixed_lambda_global = [](int f) {
__builtin_va_start(ap, f); // expected-error {{'va_start' used in function with fixed args}}
};
auto varargs_lambda_global = [](int f, ...) {
__builtin_va_start(ap, f); // correct
};
void record_member_init(int a, ...) {
struct Foo {
int a = 0;
// expected-error@+1 {{'va_start' cannot be used outside a function}}
int b = (__builtin_va_start(ap, a), 0);
};
}
#endif