1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <list> 11 12 // void push_front(const value_type& x); 13 14 #include <list> 15 #include <cassert> 16 17 // Flag that makes the copy constructor for CMyClass throw an exception 18 static bool gCopyConstructorShouldThow = false; 19 20 21 class CMyClass { 22 public: CMyClass(); 23 public: CMyClass(const CMyClass& iOther); 24 public: ~CMyClass(); 25 26 private: int fMagicValue; 27 28 private: static int kStartedConstructionMagicValue; 29 private: static int kFinishedConstructionMagicValue; 30 }; 31 32 // Value for fMagicValue when the constructor has started running, but not yet finished 33 int CMyClass::kStartedConstructionMagicValue = 0; 34 // Value for fMagicValue when the constructor has finished running 35 int CMyClass::kFinishedConstructionMagicValue = 12345; 36 37 CMyClass::CMyClass() : 38 fMagicValue(kStartedConstructionMagicValue) 39 { 40 // Signal that the constructor has finished running 41 fMagicValue = kFinishedConstructionMagicValue; 42 } 43 44 CMyClass::CMyClass(const CMyClass& /*iOther*/) : 45 fMagicValue(kStartedConstructionMagicValue) 46 { 47 // If requested, throw an exception _before_ setting fMagicValue to kFinishedConstructionMagicValue 48 if (gCopyConstructorShouldThow) { 49 throw std::exception(); 50 } 51 // Signal that the constructor has finished running 52 fMagicValue = kFinishedConstructionMagicValue; 53 } 54 55 CMyClass::~CMyClass() { 56 // Only instances for which the constructor has finished running should be destructed 57 assert(fMagicValue == kFinishedConstructionMagicValue); 58 } 59 60 int main() 61 { 62 CMyClass instance; 63 std::list<CMyClass> vec; 64 65 vec.push_front(instance); 66 67 gCopyConstructorShouldThow = true; 68 try { 69 vec.push_front(instance); 70 } 71 catch (...) { 72 } 73 } 74
