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2014/06/16

C++N3242, 2011(126) 12.8 Copying and moving class objects

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// 1 filename:cpp2011-12-8.cpp
// ver 0.1 June.15, 2014
//
// 2 original examples and/or notes:
// (c) ISO/IEC JTC1 SC22 WG21 N3242, April 12, 2011
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
// > 12 Special member functions 12.8 Copying and moving class objects
//
// 3 compile and output mechanism:
// (c) Dr. OGAWA Kiyoshi, kaizen at gifu-u.ac.jp,
//
// 4 compile errors and/or warnings:
// 4.1(c) Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
// Target: x86_64-apple-darwin13.2.0,  Thread model: posix
// Command/Options: c++ -std=c++11 -stdlib=libc++ -Wall cpp2011-12-8.cpp 
// (c) LLVM 2003-2009 University of Illinois at Urbana-Champaign.

// 4.2. g++-4.9 (GCC) 4.9.0 20131229 (experimental)
// Copyright (C) 2013 Free Software Foundation, Inc.
// This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
// http://gcc.gnu.org/onlinedocs/gcc/Standards.html
// Command/Options: g++-4.9  -std=c++11  -Wall cpp2011-12-8.cpp 
// g++-4.9: error: unrecognized command line option '-stdlib=libc++'
// Configuration:brew install gcc49
//
// 4.3. Visual Studio Express 2013, 
// (c) Microsoft http://www.visualstudio.com/
// SPEC:
// Windows 7, .NET Framework
// (c) VMware, Inc.
// VMWare fusion 6
//
// 5. Hardware:  MacBook Pro, 
//(c) Intel http://ark.intel.com/products/37006/
//Core 2 Duo 2.53GHz, 8GB, 1067MHz DDR3
//
// 6. Special Thanks: Upper organizatios and 
// ITSCJ/IPSJ http://www.itscj.ipsj.or.jp/itscj_english/index.html
// Renesas Electronics Corporation.http://www.renesas.com/
// NPO SESSAME project, http://www.sessame.jp/workinggroup/WorkingGroup3/
// Toyo Corporation, http://www.toyo.co.jp/English/
// Japan Standard Association, http://bit.ly/1lzykg1
// NPO TOPPERS project, https://www.toppers.jp/asp-d-download.html
// Daido Universcity, http://www.daido-it.ac.jp/gakubugakka/computer/index.html
// WITZ Co.Ltd., http://www.witz-inc.co.jp/products/solution/solution.html
// SevenWise.co., http://www.7ws.co.jp/index.html
// TOYOTA Motor Corporation, http://toyota.jp/
// IT planning Inc., http://www.itpl.co.jp/en/index.html
// DENSO Corporation, http://www.globaldenso.com/en/
// Aisin Seiki co. Ltd., http://www.aisin.com/
// Spancion Inc., http://www.spansion.com/
// Yazaki Corporation, http://www.yazaki-group.com/global/
// Pananosic Corporation, http://www.panasonic.net/
// SWEST: Summer Workshop on Embedded System Technologies , http://swest.toppers.jp
// CEST: Consortium for Embedded System Technology, http://www.ertl.jp/CEST/
// JUSE: Union of Japanese Scientists and Engineers, http://www.juse.or.jp/e/
// OSC:Open Source Conference, http://www.ospn.jp/

#include <iostream>
//#include <cstdlib>
//#include <string.h>
//#include <cstring>
//#include <type_traits>
//#include <cassert>
//#include <algorithm>
//#include <cmath>
#include <complex>
//#include <cstddef>
//#include <new>
//#include <vector>

using namespace std;

struct X {
X(int);
X(const X&, int = 1);
};
X a(1); // calls X(int);
X b(a, 0); // calls X(const X&, int);
X c = b; // calls X(const X&, int);
//
struct Y {
Y(const Y&);
Y(Y&&);
};
extern Y f(int);
Y d(f(1)); // calls Y(Y&&)
Y e = d; // calls Y(const Y&)
//
struct X1 {
X1(const X1&);
X1(X1&); // OK
X1(X1&&);
X1(const X1&&); // OK, but possibly not sensible
};
//
struct X2 {
X2(); // default constructor
X2(X2&); // copy constructor with a nonconst parameter
};
const X2 cx;
//error: X2 x = cx; // error: X::X(X&) cannot copy cx into x
//
struct S {
template<typename T> S(T);
template<typename T> S(T&&);
S();
};
S f();
const S g;
void h() {
S a( f() ); // does not instantiate member template;
// uses the implicitly generated move constructor
S b(g); // does not instantiate the member template;
// uses the implicitly generated copy constructor
}
//
struct X3 {
X3(const X3&, int);
};
//
X3::X3(const X3& x, int i =0) { /* ... */ }
//
X3::X3(const X3&);
//
X3::X3(X3&);
//
X3::X3(X3&&);
//
struct X4 {
X4();
X4& operator=(X4&);
};
const X4 cx4;
X4 x;
void f4() {
//error: x = cx; // error: X::operator=(X&) cannot assign cx into x
}
//
X4& X4::operator=(const X4&);
//
X4& X4::operator=(X4&);
//
struct S1 {
int a;
S1& operator=(const S1&) = default;
};
//
struct S2 {
int a;
S2& operator=(const S2&) = default;
S2& operator=(S2&&) = default;
};
//
X4& X4::operator=(X4&&);
//
struct V { };
struct A : virtual V { };
struct B : virtual V { };
struct C : B, A { };
//
class Thing {
public:
Thing();
~Thing();
Thing(const Thing&);
};
Thing f5() {
Thing t;
return t;
}
Thing t2 = f5();
//
class Thing2 {
public:
Thing2();
~Thing2();
Thing2(Thing2&&);
private:
Thing2(const Thing2&);
};
Thing2 f5(bool b) {
Thing2 t;
if (b)
throw t; // OK: Thing(Thing&&) used (or elided) to throw t
return t; // OK: Thing(Thing&&) used (or elided) to return t
}
Thing2 t2 = f5(false); // OK: Thing(Thing&&) used (or elided) to construct t2
//
int main() {
//
cout << "12 Special member functions 12.8 Copying and moving class objects" << std::endl;
return 0;
}
// 1 error
// 1.1 llvm:  c++ -std=c++11 -stdlib=libc++  -Wall cpp2011-12-8.cpp 
cpp2011-12-8.cpp:114:3: warning: unused variable 'b' [-Wunused-variable]
S b(g); // does not instantiate the member template;
  ^
cpp2011-12-8.cpp:112:3: warning: unused variable 'a' [-Wunused-variable]
S a( f() ); // does not instantiate member template;
  ^
cpp2011-12-8.cpp:122:25: error: addition of default argument on redeclaration makes this constructor a copy constructor
X3::X3(const X3& x, int i =0) { /* ... */ }
                        ^  ~
cpp2011-12-8.cpp:119:1: note: previous declaration is here
X3(const X3&, int);
^
cpp2011-12-8.cpp:124:5: error: definition of implicitly declared copy constructor
X3::X3(const X3&);
    ^
cpp2011-12-8.cpp:126:5: error: out-of-line declaration of 'X3' does not match any declaration in 'X3'
X3::X3(X3&);
    ^~
cpp2011-12-8.cpp:118:8: note: type of 1st parameter of member declaration does not match definition ('const X3 &' vs 'X3 &')
struct X3 {
       ^
cpp2011-12-8.cpp:118:8: note: type of 1st parameter of member declaration does not match definition ('X3 &&' vs 'X3 &')
cpp2011-12-8.cpp:128:5: error: definition of implicitly declared move constructor
X3::X3(X3&&);
    ^
cpp2011-12-8.cpp:140:9: error: out-of-line declaration of 'operator=' does not match any declaration in 'X4'
X4& X4::operator=(const X4&);
        ^~~~~~~~
cpp2011-12-8.cpp:132:15: note: type of 1st parameter of member declaration does not match definition ('X4 &' vs 'const X4 &')
X4& operator=(X4&);
              ^
cpp2011-12-8.cpp:142:9: error: out-of-line declaration of a member must be a definition [-Wout-of-line-declaration]
X4& X4::operator=(X4&);
    ~~~~^
cpp2011-12-8.cpp:155:9: error: out-of-line declaration of 'operator=' does not match any declaration in 'X4'
X4& X4::operator=(X4&&);
        ^~~~~~~~
cpp2011-12-8.cpp:142:19: note: type of 1st parameter of member declaration does not match definition ('X4 &' vs 'X4 &&')
X4& X4::operator=(X4&);
                  ^
cpp2011-12-8.cpp:140:25: note: type of 1st parameter of member declaration does not match definition ('const X4 &' vs 'X4 &&')
X4& X4::operator=(const X4&);
                        ^
cpp2011-12-8.cpp:188:8: error: redefinition of 't2' with a different type: 'Thing2' vs 'Thing'
Thing2 t2 = f5(false); // OK: Thing(Thing&&) used (or elided) to construct t2
       ^
cpp2011-12-8.cpp:172:7: note: previous definition is here
Thing t2 = f5();
      ^
>2 warnings and 8 errors generated.
// 1.2 gcc: g++-4.9 -std=c++11 -Wall cpp2011-12-8.cpp 
cpp2011-12-8.cpp:124:17: error: definition of implicitly-declared 'constexpr X3::X3(const X3&)'
 X3::X3(const X3&);
                 ^
cpp2011-12-8.cpp:126:1: error: prototype for 'X3::X3(X3&)' does not match any in class 'X3'
 X3::X3(X3&);
 ^
cpp2011-12-8.cpp:118:8: error: candidates are: constexpr X3::X3(X3&&)
 struct X3 {
        ^
cpp2011-12-8.cpp:118:8: error:                 constexpr X3::X3(const X3&)
cpp2011-12-8.cpp:122:1: error:                 X3::X3(const X3&, int)
 X3::X3(const X3& x, int i =0) { /* ... */ }
 ^
cpp2011-12-8.cpp:128:12: error: definition of implicitly-declared 'constexpr X3::X3(X3&&)'
 X3::X3(X3&&);
            ^
cpp2011-12-8.cpp:140:5: error: prototype for 'X4& X4::operator=(const X4&)' does not match any in class 'X4'
 X4& X4::operator=(const X4&);
     ^
cpp2011-12-8.cpp:132:5: error: candidate is: X4& X4::operator=(X4&)
 X4& operator=(X4&);
     ^
cpp2011-12-8.cpp:142:22: error: declaration of 'X4& X4::operator=(X4&)' outside of class is not definition [-fpermissive]
 X4& X4::operator=(X4&);
                      ^
cpp2011-12-8.cpp:155:5: error: prototype for 'X4& X4::operator=(X4&&)' does not match any in class 'X4'
 X4& X4::operator=(X4&&);
     ^
cpp2011-12-8.cpp:142:5: error: candidate is: X4& X4::operator=(X4&)
 X4& X4::operator=(X4&);
     ^
cpp2011-12-8.cpp:188:8: error: conflicting declaration 'Thing2 t2'
 Thing2 t2 = f5(false); // OK: Thing(Thing&&) used (or elided) to construct t2
        ^
cpp2011-12-8.cpp:172:7: note: previous declaration as 'Thing t2'
 Thing t2 = f5();
       ^


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