reinterpret-cast.cpp revision b464a5b18916b467ed884d07f9e34295d39cec0a 
1// RUN: %clang_cc1 -fsyntax-only -verify -ffreestanding %s
2
3#include <stdint.h>
4
5enum test { testval = 1 };
6struct structure { int m; };
7typedef void (*fnptr)();
8
9// Test the conversion to self.
10void self_conversion()
11{
12  // T*->T* is allowed, T->T in general not.
13  int i = 0;
14  (void)reinterpret_cast<int>(i); // expected-error {{reinterpret_cast from 'int' to 'int' is not allowed}}
15  structure s;
16  (void)reinterpret_cast<structure>(s); // expected-error {{reinterpret_cast from 'structure' to 'structure' is not allowed}}
17  int *pi = 0;
18  (void)reinterpret_cast<int*>(pi);
19}
20
21// Test conversion between pointer and integral types, as in /3 and /4.
22void integral_conversion()
23{
24  void *vp = reinterpret_cast<void*>(testval);
25  intptr_t i = reinterpret_cast<intptr_t>(vp);
26  (void)reinterpret_cast<float*>(i);
27  fnptr fnp = reinterpret_cast<fnptr>(i);
28  (void)reinterpret_cast<char>(fnp); // expected-error {{cast from pointer to smaller type 'char' loses information}}
29  (void)reinterpret_cast<intptr_t>(fnp);
30}
31
32void pointer_conversion()
33{
34  int *p1 = 0;
35  float *p2 = reinterpret_cast<float*>(p1);
36  structure *p3 = reinterpret_cast<structure*>(p2);
37  typedef int **ppint;
38  ppint *deep = reinterpret_cast<ppint*>(p3);
39  (void)reinterpret_cast<fnptr*>(deep);
40}
41
42void constness()
43{
44  int ***const ipppc = 0;
45  // Valid: T1* -> T2 const*
46  int const *icp = reinterpret_cast<int const*>(ipppc);
47  // Invalid: T1 const* -> T2*
48  (void)reinterpret_cast<int*>(icp); // expected-error {{reinterpret_cast from 'const int *' to 'int *' casts away qualifiers}}
49  // Invalid: T1*** -> T2 const* const**
50  int const *const **icpcpp = reinterpret_cast<int const* const**>(ipppc); // expected-error {{reinterpret_cast from 'int ***' to 'const int *const **' casts away qualifiers}}
51  // Valid: T1* -> T2*
52  int *ip = reinterpret_cast<int*>(icpcpp);
53  // Valid: T* -> T const*
54  (void)reinterpret_cast<int const*>(ip);
55  // Valid: T*** -> T2 const* const* const*
56  (void)reinterpret_cast<int const* const* const*>(ipppc);
57}
58
59void fnptrs()
60{
61  typedef int (*fnptr2)(int);
62  fnptr fp = 0;
63  (void)reinterpret_cast<fnptr2>(fp);
64  void *vp = reinterpret_cast<void*>(fp);
65  (void)reinterpret_cast<fnptr>(vp);
66}
67
68void refs()
69{
70  long l = 0;
71  char &c = reinterpret_cast<char&>(l);
72  // Bad: from rvalue
73  (void)reinterpret_cast<int&>(&c); // expected-error {{reinterpret_cast from rvalue to reference type 'int &'}}
74}
75
76void memptrs()
77{
78  const int structure::*psi = 0;
79  (void)reinterpret_cast<const float structure::*>(psi);
80  (void)reinterpret_cast<int structure::*>(psi); // expected-error {{reinterpret_cast from 'const int structure::*' to 'int structure::*' casts away qualifiers}}
81
82  void (structure::*psf)() = 0;
83  (void)reinterpret_cast<int (structure::*)()>(psf);
84
85  (void)reinterpret_cast<void (structure::*)()>(psi); // expected-error {{reinterpret_cast from 'const int structure::*' to 'void (structure::*)()' is not allowed}}
86  (void)reinterpret_cast<int structure::*>(psf); // expected-error {{reinterpret_cast from 'void (structure::*)()' to 'int structure::*' is not allowed}}
87
88  // Cannot cast from integers to member pointers, not even the null pointer
89  // literal.
90  (void)reinterpret_cast<void (structure::*)()>(0); // expected-error {{reinterpret_cast from 'int' to 'void (structure::*)()' is not allowed}}
91  (void)reinterpret_cast<int structure::*>(0); // expected-error {{reinterpret_cast from 'int' to 'int structure::*' is not allowed}}
92}
93
94namespace PR5545 {
95// PR5545
96class A;
97class B;
98void (A::*a)();
99void (B::*b)() = reinterpret_cast<void (B::*)()>(a);
100}
101
102// <rdar://problem/8018292>
103void const_arrays() {
104  typedef char STRING[10];
105  const STRING *s;
106  const char *c;
107
108  (void)reinterpret_cast<char *>(s); // expected-error {{reinterpret_cast from 'const STRING *' (aka 'char const (*)[10]') to 'char *' casts away qualifiers}}
109  (void)reinterpret_cast<const STRING *>(c);
110}
111
112namespace PR9564 {
113  struct a { int a : 10; }; a x;
114  int *y = &reinterpret_cast<int&>(x.a); // expected-error {{reinterpret_cast of a bit-field to 'int &' needs its address which is not allowed}}
115}
116