1*67e74705SXin Li // RUN: %clang_cc1 -fsyntax-only -verify %s 2*67e74705SXin Li // RUN: %clang_cc1 -fsyntax-only -verify -std=c++98 %s 3*67e74705SXin Li // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s 4*67e74705SXin Li 5*67e74705SXin Li struct A {}; 6*67e74705SXin Li 7*67e74705SXin Li // See if aliasing can confuse this baby. 8*67e74705SXin Li typedef char c; 9*67e74705SXin Li typedef c *cp; 10*67e74705SXin Li typedef cp *cpp; 11*67e74705SXin Li typedef cpp *cppp; 12*67e74705SXin Li typedef cppp &cpppr; 13*67e74705SXin Li typedef const cppp &cpppcr; 14*67e74705SXin Li typedef const char cc; 15*67e74705SXin Li typedef cc *ccp; 16*67e74705SXin Li typedef volatile ccp ccvp; 17*67e74705SXin Li typedef ccvp *ccvpp; 18*67e74705SXin Li typedef const volatile ccvpp ccvpcvp; 19*67e74705SXin Li typedef ccvpcvp *ccvpcvpp; 20*67e74705SXin Li typedef int iar[100]; 21*67e74705SXin Li typedef iar &iarr; 22*67e74705SXin Li typedef int (*f)(int); 23*67e74705SXin Li good_const_cast_test(ccvpcvpp var)24*67e74705SXin Lichar ***good_const_cast_test(ccvpcvpp var) 25*67e74705SXin Li { 26*67e74705SXin Li // Cast away deep consts and volatiles. 27*67e74705SXin Li char ***var2 = const_cast<cppp>(var); 28*67e74705SXin Li char ***const &var3 = var2; 29*67e74705SXin Li // Const reference to reference. 30*67e74705SXin Li char ***&var4 = const_cast<cpppr>(var3); 31*67e74705SXin Li // Drop reference. Intentionally without qualifier change. 32*67e74705SXin Li char *** var5 = const_cast<cppp>(var4); 33*67e74705SXin Li // Const array to array reference. 34*67e74705SXin Li const int ar[100] = {0}; 35*67e74705SXin Li int (&rar)[100] = const_cast<iarr>(ar); 36*67e74705SXin Li // Array decay. Intentionally without qualifier change. 37*67e74705SXin Li int *pi = const_cast<int*>(ar); 38*67e74705SXin Li f fp = 0; 39*67e74705SXin Li // Don't misidentify fn** as a function pointer. 40*67e74705SXin Li f *fpp = const_cast<f*>(&fp); 41*67e74705SXin Li int const A::* const A::*icapcap = 0; 42*67e74705SXin Li int A::* A::* iapap = const_cast<int A::* A::*>(icapcap); 43*67e74705SXin Li (void)const_cast<A&&>(A()); 44*67e74705SXin Li #if __cplusplus <= 199711L // C++03 or earlier modes 45*67e74705SXin Li // expected-warning@-2 {{rvalue references are a C++11 extension}} 46*67e74705SXin Li #endif 47*67e74705SXin Li return var4; 48*67e74705SXin Li } 49*67e74705SXin Li bad_const_cast_test(char const * volatile * const volatile * var)50*67e74705SXin Lishort *bad_const_cast_test(char const *volatile *const volatile *var) 51*67e74705SXin Li { 52*67e74705SXin Li // Different pointer levels. 53*67e74705SXin Li char **var2 = const_cast<char**>(var); // expected-error {{const_cast from 'const char *volatile *const volatile *' to 'char **' is not allowed}} 54*67e74705SXin Li // Different final type. 55*67e74705SXin Li short ***var3 = const_cast<short***>(var); // expected-error {{const_cast from 'const char *volatile *const volatile *' to 'short ***' is not allowed}} 56*67e74705SXin Li // Rvalue to reference. 57*67e74705SXin Li char ***&var4 = const_cast<cpppr>(&var2); // expected-error {{const_cast from rvalue to reference type 'cpppr'}} 58*67e74705SXin Li // Non-pointer. 59*67e74705SXin Li 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}} 60*67e74705SXin Li const int *ar[100] = {0}; 61*67e74705SXin Li // Not even lenient g++ accepts this. 62*67e74705SXin Li int *(*rar)[100] = const_cast<int *(*)[100]>(&ar); // expected-error {{const_cast from 'const int *(*)[100]' to 'int *(*)[100]' is not allowed}} 63*67e74705SXin Li f fp1 = 0; 64*67e74705SXin Li // Function pointers. 65*67e74705SXin Li 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}} 66*67e74705SXin Li void (A::*mfn)() = 0; 67*67e74705SXin Li (void)const_cast<void (A::*)()>(mfn); // expected-error-re {{const_cast to 'void (A::*)(){{( __attribute__\(\(thiscall\)\))?}}', which is not a reference, pointer-to-object, or pointer-to-data-member}} 68*67e74705SXin Li (void)const_cast<int&&>(0); // expected-error {{const_cast from rvalue to reference type 'int &&'}} 69*67e74705SXin Li #if __cplusplus <= 199711L // C++03 or earlier modes 70*67e74705SXin Li // expected-warning@-2 {{rvalue references are a C++11 extension}} 71*67e74705SXin Li #endif 72*67e74705SXin Li return **var3; 73*67e74705SXin Li } 74*67e74705SXin Li 75*67e74705SXin Li template <typename T> PR21845()76*67e74705SXin Lichar *PR21845() { return const_cast<char *>((void)T::x); } // expected-error {{const_cast from 'void' to 'char *' is not allowed}} 77