1 /* { dg-do compile } */ 2 3 typedef __SIZE_TYPE__ size_t; 4 extern "C" void *memcpy (void *, __const void *, size_t); 5 template < class Dest, class Source > struct BitCastHelper { castBitCastHelper6 static Dest cast (const Source & source) __attribute__ ((always_inline)) { 7 Dest dest; 8 memcpy (0, &source, sizeof dest); 9 } 10 }; BitCast(Source)11template < class Dest, class Source > Dest BitCast (Source) 12 { 13 BitCastHelper < Dest, Source >::cast (0); 14 } 15 16 class MaybeObject 17 { 18 }; 19 class Object:MaybeObject 20 { 21 public: cast(Object *)22 static Object *cast (Object *) { 23 } 24 }; 25 class HeapObject:public Object 26 { 27 }; 28 class String:public HeapObject 29 { 30 }; 31 class ExternalString:public String 32 { 33 }; 34 class ExternalTwoByteString:public ExternalString 35 { 36 }; 37 38 template < typename T > class Handle 39 { 40 public: Handle()41 Handle () { 42 } 43 T *operator* () const; cast(Handle<S> that)44 template < class S > static Handle < T > cast (Handle < S > that) { 45 T::cast (*that); 46 } 47 T **location_; 48 }; 49 50 template < typename T > T * Handle < T >::operator* () const 51 { 52 *BitCast < T ** >(location_); 53 } 54 55 void TestCharacterStream()56TestCharacterStream () 57 { 58 Handle < String > uc16_string; 59 Handle < ExternalTwoByteString >::cast (uc16_string); 60 } 61