cstyle-cast.cpp revision a5728872c7702ddd09537c95bc3cbd20e1f2fb09
1// RUN: %clang_cc1 -fsyntax-only -verify -faccess-control %s 2 3struct A {}; 4 5// ----------- const_cast -------------- 6 7typedef char c; 8typedef c *cp; 9typedef cp *cpp; 10typedef cpp *cppp; 11typedef cppp &cpppr; 12typedef const cppp &cpppcr; 13typedef const char cc; 14typedef cc *ccp; 15typedef volatile ccp ccvp; 16typedef ccvp *ccvpp; 17typedef const volatile ccvpp ccvpcvp; 18typedef ccvpcvp *ccvpcvpp; 19typedef int iar[100]; 20typedef iar &iarr; 21typedef int (*f)(int); 22 23void t_cc() 24{ 25 ccvpcvpp var = 0; 26 // Cast away deep consts and volatiles. 27 char ***var2 = (cppp)(var); 28 char ***const &var3 = var2; 29 // Const reference to reference. 30 char ***&var4 = (cpppr)(var3); 31 // Drop reference. Intentionally without qualifier change. 32 char *** var5 = (cppp)(var4); 33 const int ar[100] = {0}; 34 // Array decay. Intentionally without qualifier change. 35 int *pi = (int*)(ar); 36 f fp = 0; 37 // Don't misidentify fn** as a function pointer. 38 f *fpp = (f*)(&fp); 39 int const A::* const A::*icapcap = 0; 40 int A::* A::* iapap = (int A::* A::*)(icapcap); 41} 42 43// ----------- static_cast ------------- 44 45struct B : public A {}; // Single public base. 46struct C1 : public virtual B {}; // Single virtual base. 47struct C2 : public virtual B {}; 48struct D : public C1, public C2 {}; // Diamond 49struct E : private A {}; // Single private base. 50struct F : public C1 {}; // Single path to B with virtual. 51struct G1 : public B {}; 52struct G2 : public B {}; 53struct H : public G1, public G2 {}; // Ambiguous path to B. 54 55enum Enum { En1, En2 }; 56enum Onom { On1, On2 }; 57 58struct Co1 { operator int(); }; 59struct Co2 { Co2(int); }; 60struct Co3 { }; 61struct Co4 { Co4(Co3); operator Co3(); }; 62 63// Explicit implicits 64void t_529_2() 65{ 66 int i = 1; 67 (void)(float)(i); 68 double d = 1.0; 69 (void)(float)(d); 70 (void)(int)(d); 71 (void)(char)(i); 72 (void)(unsigned long)(i); 73 (void)(int)(En1); 74 (void)(double)(En1); 75 (void)(int&)(i); 76 (void)(const int&)(i); 77 78 int ar[1]; 79 (void)(const int*)(ar); 80 (void)(void (*)())(t_529_2); 81 82 (void)(void*)(0); 83 (void)(void*)((int*)0); 84 (void)(volatile const void*)((const int*)0); 85 (void)(A*)((B*)0); 86 (void)(A&)(*((B*)0)); 87 (void)(const B*)((C1*)0); 88 (void)(B&)(*((C1*)0)); 89 (void)(A*)((D*)0); 90 (void)(const A&)(*((D*)0)); 91 (void)(int B::*)((int A::*)0); 92 (void)(void (B::*)())((void (A::*)())0); 93 (void)(A*)((E*)0); // C-style cast ignores access control 94 (void)(void*)((const int*)0); // const_cast appended 95 96 (void)(int)(Co1()); 97 (void)(Co2)(1); 98 (void)(Co3)((Co4)(Co3())); 99 100 // Bad code below 101 //(void)(A*)((H*)0); // {{static_cast from 'struct H *' to 'struct A *' is not allowed}} 102} 103 104// Anything to void 105void t_529_4() 106{ 107 (void)(1); 108 (void)(t_529_4); 109} 110 111// Static downcasts 112void t_529_5_8() 113{ 114 (void)(B*)((A*)0); 115 (void)(B&)(*((A*)0)); 116 (void)(const G1*)((A*)0); 117 (void)(const G1&)(*((A*)0)); 118 (void)(B*)((const A*)0); // const_cast appended 119 (void)(B&)(*((const A*)0)); // const_cast appended 120 (void)(E*)((A*)0); // access control ignored 121 (void)(E&)(*((A*)0)); // access control ignored 122 123 // Bad code below 124 125 (void)(C1*)((A*)0); // expected-error {{cannot cast 'struct A *' to 'struct C1 *' via virtual base 'struct B'}} 126 (void)(C1&)(*((A*)0)); // expected-error {{cannot cast 'struct A' to 'struct C1 &' via virtual base 'struct B'}} 127 (void)(D*)((A*)0); // expected-error {{cannot cast 'struct A *' to 'struct D *' via virtual base 'struct B'}} 128 (void)(D&)(*((A*)0)); // expected-error {{cannot cast 'struct A' to 'struct D &' via virtual base 'struct B'}} 129 (void)(H*)((A*)0); // expected-error {{ambiguous cast from base 'struct A' to derived 'struct H':\n struct A -> struct B -> struct G1 -> struct H\n struct A -> struct B -> struct G2 -> struct H}} 130 (void)(H&)(*((A*)0)); // expected-error {{ambiguous cast from base 'struct A' to derived 'struct H':\n struct A -> struct B -> struct G1 -> struct H\n struct A -> struct B -> struct G2 -> struct H}} 131 132 // TODO: Test DR427. This requires user-defined conversions, though. 133} 134 135// Enum conversions 136void t_529_7() 137{ 138 (void)(Enum)(1); 139 (void)(Enum)(1.0); 140 (void)(Onom)(En1); 141 142 // Bad code below 143 144 (void)(Enum)((int*)0); // expected-error {{C-style cast from 'int *' to 'enum Enum' is not allowed}} 145} 146 147// Void pointer to object pointer 148void t_529_10() 149{ 150 (void)(int*)((void*)0); 151 (void)(const A*)((void*)0); 152 (void)(int*)((const void*)0); // const_cast appended 153} 154 155// Member pointer upcast. 156void t_529_9() 157{ 158 (void)(int A::*)((int B::*)0); 159 160 // Bad code below 161 (void)(int A::*)((int H::*)0); // expected-error {{ambiguous conversion from pointer to member of derived class 'struct H'}} 162 (void)(int A::*)((int F::*)0); // expected-error {{conversion from pointer to member of class 'struct F'}} 163} 164 165// -------- reinterpret_cast ----------- 166 167enum test { testval = 1 }; 168struct structure { int m; }; 169typedef void (*fnptr)(); 170 171// Test conversion between pointer and integral types, as in p3 and p4. 172void integral_conversion() 173{ 174 void *vp = (void*)(testval); 175 long l = (long)(vp); 176 (void)(float*)(l); 177 fnptr fnp = (fnptr)(l); 178 (void)(char)(fnp); // expected-error {{cast from pointer to smaller type 'char' loses information}} 179 (void)(long)(fnp); 180} 181 182void pointer_conversion() 183{ 184 int *p1 = 0; 185 float *p2 = (float*)(p1); 186 structure *p3 = (structure*)(p2); 187 typedef int **ppint; 188 ppint *deep = (ppint*)(p3); 189 (void)(fnptr*)(deep); 190} 191 192void constness() 193{ 194 int ***const ipppc = 0; 195 int const *icp = (int const*)(ipppc); 196 (void)(int*)(icp); // const_cast appended 197 int const *const **icpcpp = (int const* const**)(ipppc); // const_cast appended 198 int *ip = (int*)(icpcpp); 199 (void)(int const*)(ip); 200 (void)(int const* const* const*)(ipppc); 201} 202 203void fnptrs() 204{ 205 typedef int (*fnptr2)(int); 206 fnptr fp = 0; 207 (void)(fnptr2)(fp); 208 void *vp = (void*)(fp); 209 (void)(fnptr)(vp); 210} 211 212void refs() 213{ 214 long l = 0; 215 char &c = (char&)(l); 216 // Bad: from rvalue 217 (void)(int&)(&c); // expected-error {{C-style cast from rvalue to reference type 'int &'}} 218} 219 220void memptrs() 221{ 222 const int structure::*psi = 0; 223 (void)(const float structure::*)(psi); 224 (void)(int structure::*)(psi); // const_cast appended 225 226 void (structure::*psf)() = 0; 227 (void)(int (structure::*)())(psf); 228 229 (void)(void (structure::*)())(psi); // expected-error {{C-style cast from 'int const struct structure::*' to 'void (struct structure::*)()' is not allowed}} 230 (void)(int structure::*)(psf); // expected-error {{C-style cast from 'void (struct structure::*)()' to 'int struct structure::*' is not allowed}} 231} 232