compilerplugins/clang/test/redundantcast.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include <sal/config.h>
  11
  12 #include <cstddef>
  13
  14 #include <sal/types.h>
  15
  16 #include "redundantcast.hxx"
  17
  18 void f1(char *) {}
  19 void f2(char const *) {}
  20
  21 struct D: S {};
  22
  23 enum Enum1 { X };
  24
  25 void testConstCast() {
  26     char * p1;
  27     char const * p2;
  28     p1 = nullptr;
  29     p2 = "";
  30     f1(const_cast<char *>(p1)); // expected-error {{redundant const_cast from 'char *' lvalue to 'char *' prvalue [loplugin:redundantcast]}}
  31     f1(const_cast<char * const>(p1)); // expected-error {{redundant const_cast from 'char *' lvalue to 'char *const' prvalue [loplugin:redundantcast]}}
  32     f1(const_cast<char *>(p2));
  33     f1(const_cast<char * const>(p2));
  34     f2(const_cast<char *>(p1)); // expected-error {{redundant const_cast from 'char *' lvalue to 'char *' prvalue [loplugin:redundantcast]}}
  35     f2(const_cast<char * const>(p1)); //  expected-error {{redundant const_cast from 'char *' lvalue to 'char *const' prvalue [loplugin:redundantcast]}}
  36     f2(const_cast<char const *>(p1));
  37     f2(const_cast<char const * const>(p1));
  38     f2(const_cast<char *>(p2)); // expected-error {{redundant const_cast from 'const char *' to 'char *', result is implicitly cast to 'const char *' [loplugin:redundantcast]}}
  39     f2(const_cast<char * const>(p2)); // expected-error {{redundant const_cast from 'const char *' to 'char *', result is implicitly cast to 'const char *' [loplugin:redundantcast]}}
  40     f2(const_cast<char const *>(p2)); // expected-error {{redundant const_cast from 'const char *' lvalue to 'const char *' prvalue [loplugin:redundantcast]}}
  41     f2(const_cast<char const * const>(p2)); // expected-error {{redundant const_cast from 'const char *' lvalue to 'const char *const' prvalue [loplugin:redundantcast]}}
  42
  43     void * vp = nullptr;
  44     (void) const_cast<char *>(static_cast<char const *>(vp)); // expected-error {{redundant static_cast/const_cast combination from 'void *' via 'const char *' to 'char *' [loplugin:redundantcast]}}
  45     (void) const_cast<char *>(static_cast<char const *>(nullptr)); // expected-error-re {{redundant static_cast/const_cast combination from '{{(std::)?}}nullptr_t' via 'const char *' to 'char *' [loplugin:redundantcast]}}
  46     (void) const_cast<S &>(static_cast<S const &>(D{})); // expected-error {{redundant static_cast/const_cast combination from 'D' via 'const S &' to 'S &' [loplugin:redundantcast]}}
  47
  48     S const s{};
  49     const_cast<S &>(s).f1();
  50     const_cast<S &>(s).f2(); // expected-error {{redundant const_cast from 'const S' to 'S', result is implicitly cast to 'const S' [loplugin:redundantcast]}}
  51     const_cast<S &>(s).f3();
  52     s.f3();
  53
  54     // non-class lvalue, non-const:
  55     int ni{};
  56 //  (void) const_cast<int>(ni);
  57     (void) const_cast<int &>(ni); // expected-error {{redundant const_cast from 'int' lvalue to 'int &' lvalue [loplugin:redundantcast]}}
  58     (void) const_cast<int &&>(ni);
  59 //  (void) const_cast<int const>(ni);
  60     (void) const_cast<int const &>(ni);
  61     (void) const_cast<int const &&>(ni);
  62
  63     // non-class lvalue, const:
  64     int const ci{};
  65 //  (void) const_cast<int>(ci);
  66     (void) const_cast<int &>(ci);
  67     (void) const_cast<int &&>(ci);
  68 //  (void) const_cast<int const>(ci);
  69     (void) const_cast<int const &>(ci); // expected-error {{redundant const_cast from 'const int' lvalue to 'const int &' lvalue [loplugin:redundantcast]}}
  70     (void) const_cast<int const &&>(ci);
  71
  72     // non-class xvalue, non-const:
  73 //  (void) const_cast<int>(nix());
  74 //  (void) const_cast<int &>(nix());
  75     (void) const_cast<int &&>(nix()); // expected-error {{redundant const_cast from 'int' xvalue to 'int &&' xvalue [loplugin:redundantcast]}}
  76 //  (void) const_cast<int const>(nix());
  77 //  (void) const_cast<int const &>(nix());
  78     (void) const_cast<int const &&>(nix());
  79
  80     // non-class xvalue, const:
  81 //  (void) const_cast<int>(cix());
  82 //  (void) const_cast<int &>(cix());
  83     (void) const_cast<int &&>(cix());
  84 //  (void) const_cast<int const>(cix());
  85 //  (void) const_cast<int const &>(cix());
  86     (void) const_cast<int const &&>(cix()); // expected-error {{redundant const_cast from 'const int' xvalue to 'const int &&' xvalue [loplugin:redundantcast]}}
  87
  88     // non-class prvalue, non-const:
  89 //  (void) const_cast<int>(nir());
  90 //  (void) const_cast<int &>(nir());
  91 //  (void) const_cast<int &&>(nir());
  92 //  (void) const_cast<int const>(nir());
  93 //  (void) const_cast<int const &>(nir());
  94 //  (void) const_cast<int const &&>(nir());
  95
  96     // non-class prvalue, const:
  97 //  (void) const_cast<int>(cir());
  98 //  (void) const_cast<int &>(cir());
  99 //  (void) const_cast<int &&>(cir());
 100 //  (void) const_cast<int const>(cir());
 101 //  (void) const_cast<int const &>(cir());
 102 //  (void) const_cast<int const &&>(cir());
 103
 104     // class lvalue, non-const:
 105     S ns{};
 106 //    (void) const_cast<S>(ns);
 107     (void) const_cast<S &>(ns); // expected-error {{redundant const_cast from 'S' lvalue to 'S &' lvalue [loplugin:redundantcast]}}
 108     (void) const_cast<S &&>(ns);
 109 //  (void) const_cast<S const>(ns);
 110     (void) const_cast<S const &>(ns);
 111     (void) const_cast<S const &&>(ns);
 112
 113     // class lvalue, const:
 114     S const cs{};
 115 //  (void) const_cast<S>(cs);
 116     (void) const_cast<S &>(cs);
 117     (void) const_cast<S &&>(cs);
 118 //  (void) const_cast<S const>(cs);
 119     (void) const_cast<S const &>(cs); // expected-error {{redundant const_cast from 'const S' lvalue to 'const S &' lvalue [loplugin:redundantcast]}}
 120     (void) const_cast<S const &&>(cs);
 121
 122     // class xvalue, non-const:
 123 //  (void) const_cast<S>(nsx());
 124 //  (void) const_cast<S &>(nsx());
 125     (void) const_cast<S &&>(nsx()); // expected-error {{redundant const_cast from 'S' xvalue to 'S &&' xvalue [loplugin:redundantcast]}}
 126 //  (void) const_cast<S const>(nsx());
 127 //  (void) const_cast<S const &>(nsx());
 128     (void) const_cast<S const &&>(nsx());
 129
 130     // class xvalue, const:
 131 //  (void) const_cast<S>(csx());
 132 //  (void) const_cast<S &>(csx());
 133     (void) const_cast<S &&>(csx());
 134 //  (void) const_cast<S const>(csx());
 135 //  (void) const_cast<S const &>(csx());
 136     (void) const_cast<S const &&>(csx()); // expected-error {{redundant const_cast from 'const S' xvalue to 'const S &&' xvalue [loplugin:redundantcast]}}
 137
 138     // class prvalue, non-const:
 139 //  (void) const_cast<S>(nsr());
 140 //  (void) const_cast<S &>(nsr());
 141     (void) const_cast<S &&>(nsr());
 142 //  (void) const_cast<S const>(nsr());
 143 //  (void) const_cast<S const &>(nsr());
 144     (void) const_cast<S const &&>(nsr());
 145
 146     // class prvalue, const:
 147 //  (void) const_cast<S>(csr());
 148 //  (void) const_cast<S &>(csr());
 149     (void) const_cast<S &&>(csr());
 150 //  (void) const_cast<S const>(csr());
 151 //  (void) const_cast<S const &>(csr());
 152     (void) const_cast<S const &&>(csr());
 153 }
 154
 155 void testStaticCast() {
 156     // non-class lvalue, non-const:
 157     int ni{};
 158     (void) static_cast<int>(ni); // expected-error {{static_cast from 'int' lvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 159     /* => */ (void) int(ni);
 160     (void) static_cast<int &>(ni); // expected-error {{static_cast from 'int' lvalue to 'int &' lvalue is redundant [loplugin:redundantcast]}}
 161     (void) static_cast<int &&>(ni);
 162     (void) static_cast<int const>(ni); // expected-error {{in static_cast from 'int' lvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 163     /* => */ (void) static_cast<int>(ni); // expected-error {{static_cast from 'int' lvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 164     /* => */ (void) int(ni);
 165     (void) static_cast<int const &>(ni); // expected-error {{static_cast from 'int' lvalue to 'const int &' lvalue should be written as const_cast [loplugin:redundantcast]}}
 166     /* => */ (void) const_cast<int const &>(ni);
 167     (void) static_cast<int const &&>(ni); // expected-error {{static_cast from 'int' lvalue to 'const int &&' xvalue should be written as const_cast [loplugin:redundantcast]}}
 168     /* => */ (void) const_cast<int const &&>(ni);
 169
 170     // non-class lvalue, const:
 171     int const ci{};
 172     (void) static_cast<int>(ci); // expected-error {{static_cast from 'const int' lvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 173     /* => */ (void) int(ci);
 174 //  (void) static_cast<int &>(ci);
 175 //  (void) static_cast<int &&>(ci);
 176     (void) static_cast<int const>(ci); // expected-error {{in static_cast from 'const int' lvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 177     /* => */ (void) static_cast<int>(ci); // expected-error {{static_cast from 'const int' lvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 178     /* => */ (void) int(ci);
 179     (void) static_cast<int const &>(ci); // expected-error {{static_cast from 'const int' lvalue to 'const int &' lvalue is redundant [loplugin:redundantcast]}}
 180     (void) static_cast<int const &&>(ci);
 181
 182     // non-class xvalue, non-const:
 183     (void) static_cast<int>(nix()); // expected-error {{static_cast from 'int' xvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 184     /* => */ (void) int(nix());
 185 //  (void) static_cast<int &>(nix());
 186     (void) static_cast<int &&>(nix()); // expected-error {{static_cast from 'int' xvalue to 'int &&' xvalue is redundant [loplugin:redundantcast]}}
 187     (void) static_cast<int const>(nix()); // expected-error {{in static_cast from 'int' xvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 188     /* => */ (void) static_cast<int>(nix()); // expected-error {{static_cast from 'int' xvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 189     (void) static_cast<int const &>(nix());
 190     (void) static_cast<int const &&>(nix()); // expected-error {{static_cast from 'int' xvalue to 'const int &&' xvalue should be written as const_cast [loplugin:redundantcast]}}
 191     /* => */ (void) const_cast<int const &&>(nix());
 192
 193     // non-class xvalue, const:
 194     (void) static_cast<int>(cix()); // expected-error {{static_cast from 'const int' xvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 195     /* => */ (void) int(cix());
 196 //  (void) static_cast<int &>(cix());
 197 //  (void) static_cast<int &&>(cix());
 198     (void) static_cast<int const>(cix()); // expected-error {{in static_cast from 'const int' xvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 199     /* => */ (void) static_cast<int>(cix()); // expected-error {{static_cast from 'const int' xvalue to 'int' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 200     /* => */ (void) int(cix());
 201     (void) static_cast<int const &>(cix());
 202     (void) static_cast<int const &&>(cix()); // expected-error {{static_cast from 'const int' xvalue to 'const int &&' xvalue is redundant [loplugin:redundantcast]}}
 203
 204     // non-class prvalue, non-const:
 205     (void) static_cast<int>(nir()); // expected-error {{static_cast from 'int' prvalue to 'int' prvalue is redundant [loplugin:redundantcast]}}
 206 //  (void) static_cast<int &>(nir());
 207     (void) static_cast<int &&>(nir());
 208     (void) static_cast<int const>(nir()); // expected-error {{in static_cast from 'int' prvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 209     /* => */ (void) static_cast<int>(nir()); // expected-error {{static_cast from 'int' prvalue to 'int' prvalue is redundant [loplugin:redundantcast]}}
 210     (void) static_cast<int const &>(nir()); // expected-error {{static_cast from 'int' prvalue to 'const int &' lvalue is redundant [loplugin:redundantcast]}}
 211     (void) static_cast<int const &&>(nir());
 212
 213     // non-class prvalue, const:
 214     (void) static_cast<int>(cir()); // expected-error {{static_cast from 'int' prvalue to 'int' prvalue is redundant [loplugin:redundantcast]}}
 215 //  (void) static_cast<int &>(cir());
 216     (void) static_cast<int &&>(cir());
 217     (void) static_cast<int const>(cir()); // expected-error {{in static_cast from 'int' prvalue to 'const int' prvalue, remove redundant top-level const qualifier [loplugin:redundantcast]}}
 218     /* => */ (void) static_cast<int>(cir()); // expected-error {{static_cast from 'int' prvalue to 'int' prvalue is redundant [loplugin:redundantcast]}}
 219     (void) static_cast<int const &>(cir()); // expected-error {{static_cast from 'int' prvalue to 'const int &' lvalue is redundant [loplugin:redundantcast]}}
 220     (void) static_cast<int const &&>(cir());
 221
 222     // class lvalue, non-const:
 223     S ns{};
 224     (void) static_cast<S>(ns); // expected-error {{static_cast from 'S' lvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 225     /* => */ (void) S(ns);
 226     (void) static_cast<S &>(ns); // expected-error {{static_cast from 'S' lvalue to 'S &' lvalue is redundant [loplugin:redundantcast]}}
 227     (void) static_cast<S &&>(ns);
 228     (void) static_cast<S const>(ns); // expected-error {{static_cast from 'S' lvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 229     /* => */ using CS = const S; (void) CS(ns);
 230     (void) static_cast<S const &>(ns); // expected-error {{static_cast from 'S' lvalue to 'const S &' lvalue should be written as const_cast [loplugin:redundantcast]}}
 231     /* => */ (void) const_cast<S const &>(ns);
 232     (void) static_cast<S const &&>(ns); // expected-error {{static_cast from 'S' lvalue to 'const S &&' xvalue should be written as const_cast [loplugin:redundantcast]}}
 233     /* => */ (void) const_cast<S const &&>(ns);
 234
 235     // class lvalue, const:
 236     S const cs{};
 237     (void) static_cast<S>(cs); // expected-error {{static_cast from 'const S' lvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 238     /* => */ (void) S(cs);
 239 //  (void) static_cast<S &>(cs);
 240 //  (void) static_cast<S &&>(cs);
 241     (void) static_cast<S const>(cs); // expected-error {{static_cast from 'const S' lvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 242     /* => */ (void) CS(cs);
 243     (void) static_cast<S const &>(cs); // expected-error {{static_cast from 'const S' lvalue to 'const S &' lvalue is redundant [loplugin:redundantcast]}}
 244     (void) static_cast<S const &&>(cs);
 245
 246     // class xvalue, non-const:
 247     (void) static_cast<S>(nsx()); // expected-error {{static_cast from 'S' xvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 248     /* => */ (void) S(nsx());
 249 //  (void) static_cast<S &>(nsx());
 250     (void) static_cast<S &&>(nsx()); // expected-error {{static_cast from 'S' xvalue to 'S &&' xvalue is redundant [loplugin:redundantcast]}}
 251     (void) static_cast<S const>(nsx()); // expected-error {{static_cast from 'S' xvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 252     /* => */ (void) CS(nsx());
 253     (void) static_cast<S const &>(nsx());
 254     (void) static_cast<S const &&>(nsx()); // expected-error {{static_cast from 'S' xvalue to 'const S &&' xvalue should be written as const_cast [loplugin:redundantcast]}}
 255     /* => */ (void) const_cast<S const &&>(nsx());
 256
 257     // class xvalue, const:
 258     (void) static_cast<S>(csx()); // expected-error {{static_cast from 'const S' xvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 259     /* => */ (void) S(csx());
 260 //  (void) static_cast<S &>(csx());
 261 //  (void) static_cast<S &&>(csx());
 262     (void) static_cast<S const>(csx()); // expected-error {{static_cast from 'const S' xvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 263     /* => */ (void) CS(csx());
 264     (void) static_cast<S const &>(csx());
 265     (void) static_cast<S const &&>(csx()); // expected-error {{static_cast from 'const S' xvalue to 'const S &&' xvalue is redundant [loplugin:redundantcast]}}
 266
 267     // class prvalue, non-const:
 268     (void) static_cast<S>(nsr()); // expected-error {{static_cast from 'S' prvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 269     /* => */ (void) S(nsr());
 270 //  (void) static_cast<S &>(nsr());
 271     (void) static_cast<S &&>(nsr());
 272     (void) static_cast<S const>(nsr()); // expected-error {{static_cast from 'S' prvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 273     /* => */ (void) CS(nsr());
 274     (void) static_cast<S const &>(nsr()); // expected-error {{static_cast from 'S' prvalue to 'const S &' lvalue is redundant [loplugin:redundantcast]}}
 275     (void) static_cast<S const &&>(nsr()); // expected-error {{static_cast from 'S' prvalue to 'const S &&' xvalue should be written as const_cast [loplugin:redundantcast]}}
 276     /* => */ (void) const_cast<S const &&>(nsr());
 277
 278     // class prvalue, const:
 279     (void) static_cast<S>(csr()); // expected-error {{static_cast from 'const S' prvalue to 'S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 280     /* => */ (void) S(csr());
 281 //  (void) static_cast<S &>(csr());
 282 //  (void) static_cast<S &&>(csr());
 283     (void) static_cast<S const>(csr()); // expected-error {{static_cast from 'const S' prvalue to 'const S' prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 284     /* => */ (void) CS(csr());
 285     (void) static_cast<S const &>(csr()); // expected-error {{static_cast from 'const S' prvalue to 'const S &' lvalue is redundant [loplugin:redundantcast]}}
 286     (void) static_cast<S const &&>(csr());
 287 }
 288
 289 int & testReturnStaticCast(int && x) { return static_cast<int &>(x); }
 290
 291 void testFunctionalCast() {
 292     (void) int(nir()); // expected-error {{redundant functional cast from 'int' to 'int' [loplugin:redundantcast]}}
 293     (void) S(nsr());
 294 }
 295
 296 void testCStyleCast() {
 297     Enum1 e = (Enum1)Enum1::X; // expected-error {{redundant cstyle cast from 'Enum1' to 'Enum1' [loplugin:redundantcast]}}
 298     (void)e;
 299 }
 300
 301 template<typename T>
 302 struct EnumItemInterface {
 303     T GetValue() { return static_cast<T>(0); }
 304 };
 305 class Enum1Item : public EnumItemInterface<Enum1> {
 306 };
 307 bool testCStyleCastOfTemplateMethodResult(Enum1Item* item) {
 308     return (Enum1)item->GetValue() == Enum1::X; // expected-error {{redundant cstyle cast from 'Enum1' to 'Enum1' [loplugin:redundantcast]}}
 309 }
 310
 311 using T1 = int;
 312 T1 nt1r() { return 0; }
 313 void testArithmeticTypedefs() {
 314     (void) static_cast<T1>(nir());
 315     (void) T1(nir());
 316     (void) (T1) nir();
 317     (void) static_cast<int>(nt1r());
 318     (void) int(nt1r());
 319     (void) (int) nt1r();
 320     using T2 = T1;
 321     (void) static_cast<T2>(nt1r());
 322     (void) T2(nt1r());
 323     (void) (T2) nt1r();
 324     (void) static_cast<T1>(nt1r()); // expected-error {{redundant}}
 325     (void) T1(nt1r()); // expected-error {{redundant}}
 326     (void) (T1) nt1r(); // expected-error {{redundant}}
 327
 328     T1 const c{};
 329     (void) static_cast<T1>(c); // expected-error {{redundant}}
 330 }
 331
 332 void testReinterpretCast() {
 333     int * p;
 334     (void) reinterpret_cast<int *>(p); // expected-error {{redundant reinterpret_cast from 'int *' to 'int *' [loplugin:redundantcast]}}
 335 }
 336
 337 void testReinterpretConstCast() {
 338     int n = 0;
 339     (void) reinterpret_cast<std::size_t>((const_cast<int const *>(&n))); // expected-error-re {{redundant const_cast from 'int *' to 'const int *' within reinterpret_cast to fundamental type 'std::size_t' (aka 'unsigned {{.+}}') [loplugin:redundantcast]}}
 340 }
 341
 342 void testSuspiciousReinterpretCast() {
 343     D * p;
 344     // expected-error@+1 {{suspicious reinterpret_cast from derived 'D *' to base 'S *', maybe this was meant to be a static_cast [loplugin:redundantcast]}}
 345     (void) reinterpret_cast<S *>(p);
 346     (void) reinterpret_cast<sal_uIntPtr>(p); // expected no error
 347 }
 348
 349 void testDynamicCast() {
 350
 351     struct S1 { virtual ~S1(); };
 352     struct S2 final: S1 {};
 353     struct S3: S1 {};
 354
 355     S1 * s1 = nullptr;
 356     S2 * s2 = nullptr;
 357     S3 * s3 = nullptr;
 358
 359     (void) dynamic_cast<void *>(s1);
 360     (void) dynamic_cast<void const *>(s1);
 361     (void) dynamic_cast<S2 *>(s1);
 362     (void) dynamic_cast<S2 &>(*s1);
 363     (void) dynamic_cast<S1 *>(s2); // expected-error {{redundant dynamic upcast from 'S2 *' to 'S1 *' [loplugin:redundantcast]}}
 364     (void) dynamic_cast<S1 &>(*s2); // expected-error {{redundant dynamic upcast from 'S2' to 'S1 &' [loplugin:redundantcast]}}
 365     (void) dynamic_cast<S2 *>(s2); // expected-error {{redundant dynamic cast from 'S2 *' to 'S2 *' [loplugin:redundantcast]}}
 366     (void) dynamic_cast<S2 &>(*s2); // expected-error {{redundant dynamic cast from 'S2' to 'S2 &' [loplugin:redundantcast]}}
 367     (void) dynamic_cast<S3 *>(s2);
 368     (void) dynamic_cast<S3 &>(*s2);
 369     (void) dynamic_cast<const S2 *>(s2); // expected-error {{redundant dynamic cast from 'S2 *' to 'const S2 *' [loplugin:redundantcast]}}
 370     (void) dynamic_cast<const S2 &>(*s2); // expected-error {{redundant dynamic cast from 'S2' to 'const S2 &' [loplugin:redundantcast]}}
 371     (void) dynamic_cast<S1 *>(s3); // expected-error {{redundant dynamic upcast from 'S3 *' to 'S1 *' [loplugin:redundantcast]}}
 372     (void) dynamic_cast<S1&>(*s3); // expected-error {{redundant dynamic upcast from 'S3' to 'S1 &' [loplugin:redundantcast]}}
 373
 374     S1 const * c1 = nullptr;
 375     S2 const * c2 = nullptr;
 376     S3 const * c3 = nullptr;
 377
 378     (void) dynamic_cast<void const *>(c1);
 379     (void) dynamic_cast<S2 const *>(c1);
 380     (void) dynamic_cast<S2 const &>(*c1);
 381     (void) dynamic_cast<S1 const *>(c2); // expected-error {{redundant dynamic upcast from 'const S2 *' to 'const S1 *' [loplugin:redundantcast]}}
 382     (void) dynamic_cast<S1 const &>(*c2); // expected-error {{redundant dynamic upcast from 'const S2' to 'const S1 &' [loplugin:redundantcast]}}
 383
 384     (void) dynamic_cast<S2 const *>(c2); // expected-error {{redundant dynamic cast from 'const S2 *' to 'const S2 *' [loplugin:redundantcast]}}
 385     (void) dynamic_cast<S2 const &>(*c2); // expected-error {{redundant dynamic cast from 'const S2' to 'const S2 &' [loplugin:redundantcast]}}
 386     (void) dynamic_cast<S3 const *>(c2);
 387     (void) dynamic_cast<S3 const &>(*c2);
 388     (void) dynamic_cast<S1 const *>(c3); // expected-error {{redundant dynamic upcast from 'const S3 *' to 'const S1 *' [loplugin:redundantcast]}}
 389     (void) dynamic_cast<S1 const&>(*c3); // expected-error {{redundant dynamic upcast from 'const S3' to 'const S1 &' [loplugin:redundantcast]}}
 390 }
 391
 392 void overload(int);
 393 void overload(long);
 394 void nonOverload();
 395
 396 struct Overload {
 397     int overload();
 398     long overload() const;
 399     void nonOverload();
 400 };
 401
 402 void testOverloadResolution() {
 403     (void) static_cast<void (*)(long)>(overload);
 404     (void) static_cast<void (*)(long)>((overload));
 405     (void) static_cast<void (*)(long)>(&overload);
 406     (void) static_cast<void (*)(long)>((&overload));
 407     (void) static_cast<void (*)(long)>(&((overload)));
 408     (void) static_cast<void (*)()>(nonOverload); // expected-error {{static_cast from 'void (*)()' prvalue to 'void (*)()' prvalue is redundant [loplugin:redundantcast]}}
 409     (void) static_cast<void (*)()>((nonOverload)); // expected-error {{static_cast from 'void (*)()' prvalue to 'void (*)()' prvalue is redundant [loplugin:redundantcast]}}
 410     (void) static_cast<void (*)()>(&nonOverload); // expected-error {{static_cast from 'void (*)()' prvalue to 'void (*)()' prvalue is redundant [loplugin:redundantcast]}}
 411     (void) static_cast<void (*)()>((&nonOverload)); // expected-error {{static_cast from 'void (*)()' prvalue to 'void (*)()' prvalue is redundant [loplugin:redundantcast]}}
 412     (void) static_cast<void (*)()>(&((nonOverload))); // expected-error {{static_cast from 'void (*)()' prvalue to 'void (*)()' prvalue is redundant [loplugin:redundantcast]}}
 413     (void) static_cast<long (Overload::*)() const>(&Overload::overload);
 414     (void) static_cast<void (Overload::*)()>(&Overload::nonOverload); // expected-error {{static_cast from 'void (Overload::*)()' prvalue to 'void (Overload::*)()' prvalue is redundant [loplugin:redundantcast]}}
 415
 416     using OverloadFn = void (*)(long);
 417     (void) OverloadFn(overload);
 418     using NonOverloadFn = void (*)();
 419     (void) NonOverloadFn(nonOverload); // expected-error {{redundant functional cast from 'void (*)()' to 'NonOverloadFn' (aka 'void (*)()') [loplugin:redundantcast]}}
 420     using OverloadMemFn = long (Overload::*)() const;
 421     (void) OverloadMemFn(&Overload::overload);
 422     using NonOverloadMemFn = void (Overload::*)();
 423     (void) NonOverloadMemFn(&Overload::nonOverload); // expected-error {{redundant functional cast from 'void (Overload::*)()' to 'NonOverloadMemFn' (aka 'void (Overload::*)()') [loplugin:redundantcast]}}
 424 };
 425
 426 void testIntermediaryStaticCast() {
 427     int n = 0;
 428     n = static_cast<double>(n); // expected-error {{suspicious static_cast from 'int' to 'double', result is implicitly cast to 'int' [loplugin:redundantcast]}}
 429     n = double(n); // expected-error {{suspicious functional cast from 'int' to 'double', result is implicitly cast to 'int' [loplugin:redundantcast]}}
 430     double d = 0.0;
 431     d = static_cast<int>(d) + 1.0; // expected-error {{suspicious static_cast from 'double' to 'int', result is implicitly cast to 'double' [loplugin:redundantcast]}}
 432     d = int(d) + 1.0; // expected-error {{suspicious functional cast from 'double' to 'int', result is implicitly cast to 'double' [loplugin:redundantcast]}}
 433 };
 434
 435 void testArrayDecay() {
 436     (void) static_cast<char const *>(""); // expected-error-re {{redundant static_cast from 'const char{{ ?}}[1]' to 'const char *' [loplugin:redundantcast]}}
 437     (void) reinterpret_cast<char const *>(""); // expected-error-re {{redundant reinterpret_cast from 'const char{{ ?}}[1]' to 'const char *' [loplugin:redundantcast]}}
 438     (void) reinterpret_cast<char const *>(u8"");
 439 }
 440
 441 void testNew() {
 442     class A {};
 443     class B : public A {};
 444     A* p = static_cast<A*>(new B); // expected-error {{redundant static_cast from 'B *' to 'A *' [loplugin:redundantcast]}}
 445     (void)p;
 446     // no warning expected for resolving-ambiguity cast
 447     class C : public A {};
 448     class D : public B, public C {};
 449     p = static_cast<B*>(new D);
 450     // no warning expected for down-cast
 451     auto p2 = static_cast<B*>(p);
 452     (void)p2;
 453 }
 454
 455 using F = void (*)();
 456 auto testNullFunctionPointer(int i, F p) {
 457     switch (i) {
 458     case 0:
 459         return static_cast<F>(nullptr);
 460     case 1:
 461         return F(nullptr);
 462     default:
 463         return p;
 464     }
 465 }
 466
 467 void testSalIntTypes() {
 468     sal_Int16 const n = 0;
 469     (void) static_cast<sal_Int16>(n); // expected-error-re {{static_cast from 'const sal_Int16' (aka 'const {{.+}}') lvalue to 'sal_Int16' (aka '{{.+}}') prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 470     (void) static_cast<::sal_Int16>(n); // expected-error-re {{static_cast from 'const sal_Int16' (aka 'const {{.+}}') lvalue to '::sal_Int16' (aka '{{.+}}') prvalue is redundant or should be written as an explicit construction of a temporary [loplugin:redundantcast]}}
 471     (void) static_cast<short>(n); // doesn't warn, even if 'sal_Int16' is 'short'
 472     using Other = sal_Int16;
 473     (void) static_cast<Other>(n); // doesn't warn either
 474 }
 475
 476 int main() {
 477     testConstCast();
 478     testStaticCast();
 479     testFunctionalCast();
 480     testCStyleCast();
 481     testCStyleCastOfTemplateMethodResult(nullptr);
 482     testReinterpretCast();
 483     testReinterpretConstCast();
 484     testDynamicCast();
 485     testIntermediaryStaticCast();
 486     testArrayDecay();
 487     testSalIntTypes();
 488 }
 489
 490 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */