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
|
// RUN: %clang_cc1 -verify -std=c++2a -fsyntax-only -triple x86_64-apple-macosx10.14.0 %s
// RUN: %clang_cc1 -verify -std=c++2a -fsyntax-only -triple x86_64-apple-macosx10.14.0 %s -fno-signed-char
#if !__has_builtin(__builtin_bit_cast)
#error
#endif
template <class T, T v>
T instantiate() {
return __builtin_bit_cast(T, v);
}
int x = instantiate<int, 32>();
struct secret_ctor {
char member;
private: secret_ctor() = default;
};
void test1() {
secret_ctor c = __builtin_bit_cast(secret_ctor, (char)0);
}
void test2() {
constexpr int i = 0;
// expected-error@+1{{__builtin_bit_cast source size does not equal destination size (4 vs 1)}}
constexpr char c = __builtin_bit_cast(char, i);
}
struct not_trivially_copyable {
virtual void foo() {}
};
// expected-error@+1{{__builtin_bit_cast source type must be trivially copyable}}
constexpr unsigned long ul = __builtin_bit_cast(unsigned long, not_trivially_copyable{});
// expected-error@+1 {{__builtin_bit_cast destination type must be trivially copyable}}
constexpr long us = __builtin_bit_cast(unsigned long &, 0L);
namespace PR42936 {
template <class T> struct S { int m; };
extern S<int> extern_decl;
int x = __builtin_bit_cast(int, extern_decl);
S<char> y = __builtin_bit_cast(S<char>, 0);
}
|
