llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Vlad Serebrennikov (Endilll) <details> <summary>Changes</summary> This patch adds test for [CWG170](https://cplusplus.github.io/CWG/issues/170.html). The resolution adds explicit undefined behavior, so I think the best we can do is to put the test into constexpr evaluator. Change to [expr.static.cast] is not tested, because it was a drive-by fix that removed an impossible case (I confirmed it using minutes). Minutes mention several times a comprehensive paper in this design space which no one seem to remember. I believe it's [P0149R0](https://wg21.link/p0149r0) "Generalised member pointers". --- Full diff: https://github.com/llvm/llvm-project/pull/121667.diff 2 Files Affected: - (modified) clang/test/CXX/drs/cwg1xx.cpp (+20) - (modified) clang/www/cxx_dr_status.html (+1-1) ``````````diff diff --git a/clang/test/CXX/drs/cwg1xx.cpp b/clang/test/CXX/drs/cwg1xx.cpp index 6aec8b65c91f12..0110c711d6dd89 100644 --- a/clang/test/CXX/drs/cwg1xx.cpp +++ b/clang/test/CXX/drs/cwg1xx.cpp @@ -1074,6 +1074,26 @@ namespace cwg169 { // cwg169: yes }; } +namespace cwg170 { // cwg170: 3.1 +#if __cplusplus >= 201103L +struct A {}; +struct B : A { int i; }; +struct C : A {}; +struct D : C {}; + +constexpr int f(int A::*) { return 0; } +constexpr int g(int C::*) { return 0; } +constexpr int h(int D::*) { return 0; } + +constexpr auto p = static_cast<int A::*>(&B::i); +constexpr auto q = f(p); +constexpr auto r = g(p); +// since-cxx11-error@-1 {{constexpr variable 'r' must be initialized by a constant expression}} +constexpr auto s = h(p); +// since-cxx11-error@-1 {{constexpr variable 's' must be initialized by a constant expression}} +#endif +} // namespace cwg170 + namespace { // cwg171: 3.4 int cwg171a; } diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html index c069e155fd547c..935411e778b251 100755 --- a/clang/www/cxx_dr_status.html +++ b/clang/www/cxx_dr_status.html @@ -1065,7 +1065,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td><a href="https://cplusplus.github.io/CWG/issues/170.html";>170</a></td> <td>DRWP</td> <td>Pointer-to-member conversions</td> - <td class="unknown" align="center">Unknown</td> + <td class="full" align="center">Clang 3.1</td> </tr> <tr id="171"> <td><a href="https://cplusplus.github.io/CWG/issues/171.html";>171</a></td> `````````` </details> https://github.com/llvm/llvm-project/pull/121667 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
