// 1 filename:cpp2011-10-2.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 // > 10 Derived classes 10.2 Member name lookup // // 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 cpp2011-10-2.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 cpp2011-10-2.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 //#include //#include //#include //#include //#include //#include //#include //#include //#include //#include //#include using namespace std; struct A { int x; }; // S(x,A) = { { A::x }, { A } } struct B { float x; }; // S(x,B) = { { B::x }, { B } } struct C: public A, public B { }; // S(x,C) = { invalid, { A in C, B in C } } struct D: public virtual C { }; // S(x,D) = S(x,C) struct E: public virtual C { char x; }; // S(x,E) = { { E::x }, { E } } struct F: public D, public E { }; // S(x,F) = S(x,E) // struct A2 { int f(); }; struct B2 { int f(); }; struct C2 : A2, B2 { int f() { return A2::f() + B2::f(); } }; // struct V { int v; }; struct A3 { int a; static int s; enum { e }; }; struct B3 : A3, virtual V { }; struct C3 : A3, virtual V { }; struct D3 : B3, C3 { }; void f(D3* pd) { pd->v++; // OK: only one v (virtual) pd->s++; // OK: only one s (static) int i = pd->e; // OK: only one e (enumerator) //error: pd->a++; // error, ambiguous: two as in D } // struct V2 { int f(); int x; }; struct W { int g(); int y; }; struct B4 : virtual V2, W { int f(); int x; int g(); int y; }; struct C4 : virtual V2, W { }; struct D4 : B4, C4 { void glorp(); }; // void D4::glorp() { x++; // OK: B::x hides V::x f(); // OK: B::f() hides V::f() //error: y++; // error: B::y and C’s W::y //error: g(); // error: B::g() and C’s W::g() } // struct V5 { }; struct A5 { }; struct B5 : A5, virtual V5 { }; struct C5 : A5, virtual V5 { }; struct D5 : B5, C5 { }; void g() { D5 d; B5* pb = &d; //error: A5* pa = &d; // error, ambiguous: C’s A or B’s A? V5* pv = &d; // OK: only one V subobject } // struct B1 { void f(); static void f(int); int i; }; struct B6 { void f(double); }; struct I1: B1 { }; struct I2: B1 { }; struct D6: I1, I2, B6 { using B1::f; using B6::f; void g() { //error: f(); // Ambiguous conversion of this f(0); // Unambiguous (static) f(0.0); // Unambiguous (only one B2) int B1::* mpB1 = &D6::i; // Unambiguous //error: int D6::* mpD6 = &D6::i; // Ambiguous conversion } }; // int main() { F f; f.x = 0; // OK, lookup finds E::x cout << "10 Derived classes 10.2 Member name lookup" << std::endl; return 0; } // 1 output // 1.1 llvm: c++ -std=c++11 -stdlib=libc++ -Wall cpp2011-10-2.cpp cpp2011-10-2.cpp:106:5: warning: unused variable 'i' [-Wunused-variable] int i = pd->e; // OK: only one e (enumerator) ^ cpp2011-10-2.cpp:134:5: warning: unused variable 'pb' [-Wunused-variable] B5* pb = &d; ^ cpp2011-10-2.cpp:136:5: warning: unused variable 'pv' [-Wunused-variable] V5* pv = &d; // OK: only one V subobject ^ cpp2011-10-2.cpp:156:23: error: non-static member 'i' found in multiple base-class subobjects of type 'B1': struct D6 -> struct I1 -> struct B1 struct D6 -> struct I2 -> struct B1 int B1::* mpB1 = &D6::i; // Unambiguous ~~~~^ cpp2011-10-2.cpp:142:5: note: member found by ambiguous name lookup int i; ^ > 3 warnings and 1 error generated. //1.2 gcc: g++-4.9 -std=c++11 -Wall cpp2011-10-2.cpp cpp2011-10-2.cpp: In function 'void f(D3*)': cpp2011-10-2.cpp:106:5: warning: unused variable 'i' [-Wunused-variable] int i = pd->e; // OK: only one e (enumerator) ^ cpp2011-10-2.cpp: In function 'void g()': cpp2011-10-2.cpp:134:5: warning: unused variable 'pb' [-Wunused-variable] B5* pb = &d; ^ cpp2011-10-2.cpp:136:5: warning: unused variable 'pv' [-Wunused-variable] V5* pv = &d; // OK: only one V subobject ^ cpp2011-10-2.cpp: In member function 'void D6::g()': cpp2011-10-2.cpp:156:19: error: reference to 'i' is ambiguous int B1::* mpB1 = &D6::i; // Unambiguous ^ cpp2011-10-2.cpp:142:5: note: candidates are: int B1::i int i; ^ cpp2011-10-2.cpp:142:5: note: int B1::i cpp2011-10-2.cpp:156:11: warning: unused variable 'mpB1' [-Wunused-variable] int B1::* mpB1 = &D6::i; // Unambiguous ^ cpp2011-10-2.cpp: In function 'int main()': cpp2011-10-2.cpp:163:3: error: request for member 'x' is ambiguous f.x = 0; // OK, lookup finds E::x ^ cpp2011-10-2.cpp:75:18: note: candidates are: float B::x struct B { float x; }; // S(x,B) = { { B::x }, { B } } ^ cpp2011-10-2.cpp:74:16: note: int A::x struct A { int x; }; // S(x,A) = { { A::x }, { A } } ^