1 // RUN: %clang_cc1 -fsyntax-only -verify %s
2
3 struct A {};
4
5 // See if aliasing can confuse this baby.
6 typedef char c;
7 typedef c *cp;
8 typedef cp *cpp;
9 typedef cpp *cppp;
10 typedef cppp &cpppr;
11 typedef const cppp &cpppcr;
12 typedef const char cc;
13 typedef cc *ccp;
14 typedef volatile ccp ccvp;
15 typedef ccvp *ccvpp;
16 typedef const volatile ccvpp ccvpcvp;
17 typedef ccvpcvp *ccvpcvpp;
18 typedef int iar[100];
19 typedef iar &iarr;
20 typedef int (*f)(int);
21
good_const_cast_test(ccvpcvpp var)22 char ***good_const_cast_test(ccvpcvpp var)
23 {
24 // Cast away deep consts and volatiles.
25 char ***var2 = const_cast<cppp>(var);
26 char ***const &var3 = var2;
27 // Const reference to reference.
28 char ***&var4 = const_cast<cpppr>(var3);
29 // Drop reference. Intentionally without qualifier change.
30 char *** var5 = const_cast<cppp>(var4);
31 // Const array to array reference.
32 const int ar[100] = {0};
33 int (&rar)[100] = const_cast<iarr>(ar);
34 // Array decay. Intentionally without qualifier change.
35 int *pi = const_cast<int*>(ar);
36 f fp = 0;
37 // Don't misidentify fn** as a function pointer.
38 f *fpp = const_cast<f*>(&fp);
39 int const A::* const A::*icapcap = 0;
40 int A::* A::* iapap = const_cast<int A::* A::*>(icapcap);
41
42 return var4;
43 }
44
bad_const_cast_test(char const * volatile * const volatile * var)45 short *bad_const_cast_test(char const *volatile *const volatile *var)
46 {
47 // Different pointer levels.
48 char **var2 = const_cast<char**>(var); // expected-error {{const_cast from 'const char *volatile *const volatile *' to 'char **' is not allowed}}
49 // Different final type.
50 short ***var3 = const_cast<short***>(var); // expected-error {{const_cast from 'const char *volatile *const volatile *' to 'short ***' is not allowed}}
51 // Rvalue to reference.
52 char ***&var4 = const_cast<cpppr>(&var2); // expected-error {{const_cast from rvalue to reference type 'cpppr'}}
53 // Non-pointer.
54 char v = const_cast<char>(**var2); // expected-error {{const_cast to 'char', which is not a reference, pointer-to-object, or pointer-to-data-member}}
55 const int *ar[100] = {0};
56 // Not even lenient g++ accepts this.
57 int *(*rar)[100] = const_cast<int *(*)[100]>(&ar); // expected-error {{const_cast from 'const int *(*)[100]' to 'int *(*)[100]' is not allowed}}
58 f fp1 = 0;
59 // Function pointers.
60 f fp2 = const_cast<f>(fp1); // expected-error {{const_cast to 'f' (aka 'int (*)(int)'), which is not a reference, pointer-to-object, or pointer-to-data-member}}
61 void (A::*mfn)() = 0;
62 (void)const_cast<void (A::*)()>(mfn); // expected-error {{const_cast to 'void (A::*)()', which is not a reference, pointer-to-object, or pointer-to-data-member}}
63 return **var3;
64 }
65