(C++) SmartPointerExample1

 

Technical facts

 

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• Console application

C++ standard:

• C++11

Compiler(s):

• G++ 4.9.2

Libraries used:

• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppSmartPointerExample1/CppSmartPointerExample1.pro

 

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TEMPLATE = app CONFIG += console CONFIG -= app_bundle CONFIG -= qt QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Werror SOURCES += main.cpp win32 {   INCLUDEPATH += ../../Libraries/boost_1_54_0 }

 

 

 

 

 

./CppSmartPointerExample1/main.cpp

 

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#include <cassert> #include <memory> #include <boost/scoped_ptr.hpp> #include <boost/shared_ptr.hpp> struct Test { int m_x; }; int main() {   {     std::unique_ptr<Test> p;     assert(!p);     p->m_x = 42; //Danger: uninitialized pointer not detected by std::unique_ptr   }   {     std::shared_ptr<Test> p;     assert(!p);     p->m_x = 42; //Danger: uninitialized pointer not detected by std::shared_ptr   }   {     boost::shared_ptr<Test> p;     assert(!p);     p->m_x = 42; //Good: uninitialized pointer detected by boost::shared_ptr   }   {     boost::scoped_ptr<Test> p;     assert(!p);     p->m_x = 42; //Danger: uninitialized pointer not detected by boost::scoped_ptr   } }