c++ - VS compiler could access private copy ctor -


possible duplicate:
can objects private copy constructors thrown?

as know, when trow object value, copy should created. copy constructor should called if exist. if copy ctor exists , private should cause compilation error. here code sample

class exception { public: exception() {     cout << "exception()" << endl; }  ~exception() {     cout << "~exception() " << endl; } private: exception(const exception &c) {         cout << "exception(c)" << endl;     } };

and next code should lead compilation error.

try {         exception local;          throw local;     } catch (...) {     }

but both in vs 2005 , vs 2008 succesfully compile code , call private ctor. wrong non standard behaviour , error in compiler?

i'm going go out on limb here , legitimate msvc 10 bug. cannot find reference this, however.

here test harness:

#include <cstdlib> #include <string> #include <iostream> #include <iomanip> using namespace std;  class exception { public: exception() {     cout << "exception()" << endl; }  ~exception() {     cout << "~exception() " << endl; } private: exception(const exception &c) {         cout << "exception(c)" << endl;     } };  int main() {     try {         exception local;          int n = 42;          throw local;     } catch (...)      {     } }

this code should fail compile reason note -- copy constructor private , being called outside context of class.

this code compiles in msvc 10 , msvc 11 dev preview.

gcc 4.4.4 under rhel6.2 emits:

[xxx@yyy ~]$ gcc --version gcc (gcc) 4.4.4 20100726 (red hat 4.4.4-13) copyright (c) 2010 free software foundation, inc. free software; see source copying conditions.  there no warranty; not merchantability or fitness particular purpose. [xxx@yyy ~]$ gcc hack.cpp  hack.cpp: in function ‘int main()’: hack.cpp:17: error: ‘exception::exception(const exception&)’ private hack.cpp:29: error: within context [xxx@yyy ~]$

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