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2014/06/13

C++N3242, 2011 (26) 3.9 Types

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// 1 filename:cpp2011-3-9.cpp
// ver 0.1 June.12, 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
// 3 Basic concepts 3.9 Types
//
// 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 cpp2011-3-9.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 cpp2011-3-9.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>
namespace std {
    void* memcpy(void* s1, const void* s2, size_t n);
}//cpp2011-3-9.cpp:72:6: error: no member named 'memcpy' in namespace 'std'

using namespace std;
typedef  int T;
#define N sizeof(T)
//cpp2011-3-9.cpp:67:10: error: use of undeclared identifier 'T'
char buf[N];
T obj; // obj initialized to its original value
std::memcpy(buf, &obj, N); // between these two calls to std::memcpy,
// obj might be modified
std::memcpy(&obj, buf, N); // at this point, each subobject of obj of scalar type
// holds its original value
//
T* t1p;
T* t2p;
// provided that t2p points to an initialized object ...
std::memcpy(t1p, t2p, sizeof(T));
// at this point, every subobject of trivially copyable type in *t1p contains
// the same value as the corresponding subobject in *t2p

class X; // X is an incomplete type
extern X* xp; // xp is a pointer to an incomplete type
extern int arr[]; // the type of arr is incomplete
typedef int UNKA[]; // UNKA is an incomplete type
UNKA* arrp; // arrp is a pointer to an incomplete type
UNKA** arrpp;
void foo() {
//xp++; // error:ill-formed: X is incomplete
//arrp++; // error:ill-formed: incomplete type
arrpp++; // OK: sizeof UNKA* is known
}
struct X { int i; }; // now X is a complete type
int arr[10]; // now the type of arr is complete
X x;
void bar() {
xp = &x; // OK; type is “pointer to X”
//rrp = &arr; // error:ill-formed: different types
xp++; // OK: X is complete
//arrp++; // error:ill-formed: UNKA can’t be completed
}

int main() {

cout << "3 Basic concepts. 3.9 Types"<<std::endl;
return 0;
}
// error
c++ -std=c++11 -stdlib=libc++ -Wall cpp2011-3-9.cpp 
cpp2011-3-9.cpp:75:6: error: C++ requires a type specifier for all declarations
std::memcpy(buf, &obj, N); // between these two calls to std::memcpy,
~~~  ^
cpp2011-3-9.cpp:77:6: error: C++ requires a type specifier for all declarations
std::memcpy(&obj, buf, N); // at this point, each subobject of obj of scalar type
~~~  ^
cpp2011-3-9.cpp:83:6: error: C++ requires a type specifier for all declarations
std::memcpy(t1p, t2p, sizeof(T));
~~~  ^
cpp2011-3-9.cpp:98:1: warning: 'X' defined as a struct here but previously declared as a class [-Wmismatched-tags]
struct X { int i; }; // now X is a complete type
^
cpp2011-3-9.cpp:87:1: note: did you mean struct here?
class X; // X is an incomplete type
^~~~~
struct
1 warning and 3 errors generated.

g++-4.9 -std=c++11 -Wall cpp2011-3-9.cpp 
cpp2011-3-9.cpp:66:52: error: 'void* std::memcpy(void*, const void*, std::size_t)' conflicts with a previous declaration
     void* memcpy(void* s1, const void* s2, size_t n);
                                                    ^
In file included from /usr/local/Cellar/gcc49/4.9-20131229/lib/gcc/x86_64-apple-darwin13.0.0/4.9.0/include/c++/cstring:42:0,
                 from cpp2011-3-9.cpp:62:
/usr/include/string.h:72:7: note: previous declaration 'void* memcpy(void*, const void*, size_t)'
 void *memcpy(void *, const void *, size_t);
       ^
cpp2011-3-9.cpp:75:12: error: expected constructor, destructor, or type conversion before '(' token
 std::memcpy(buf, &obj, N); // between these two calls to std::memcpy,
            ^
cpp2011-3-9.cpp:77:12: error: expected constructor, destructor, or type conversion before '(' token
 std::memcpy(&obj, buf, N); // at this point, each subobject of obj of scalar type
            ^
cpp2011-3-9.cpp:83:12: error: expected constructor, destructor, or type conversion before '(' token
 std::memcpy(t1p, t2p, sizeof(T));
            ^


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