Author: ericwf Date: Mon Mar 30 10:22:20 2015 New Revision: 233552 URL: http://llvm.org/viewvc/llvm-project?rev=233552&view=rev Log: [libcxx] Fix PR22771 - Support access control SFINAE in the library version of is_convertible.
Summary: Currently the conversion check does not take place in a context where access control SFINAE is applied. This patch changes the context of the test expression so that SFINAE occurs if access control does not permit the conversion. Related bug: https://llvm.org/bugs/show_bug.cgi?id=22771 Reviewers: mclow.lists, rsmith, dim Reviewed By: dim Subscribers: dim, rodrigc, emaste, cfe-commits Differential Revision: http://reviews.llvm.org/D8461 Modified: libcxx/trunk/include/type_traits libcxx/trunk/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp Modified: libcxx/trunk/include/type_traits URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/type_traits?rev=233552&r1=233551&r2=233552&view=diff ============================================================================== --- libcxx/trunk/include/type_traits (original) +++ libcxx/trunk/include/type_traits Mon Mar 30 10:22:20 2015 @@ -848,7 +848,16 @@ template <class _T1, class _T2> struct _ namespace __is_convertible_imp { -template <class _Tp> char __test(_Tp); +template <class _Tp> void __test_convert(_Tp); + +template <class _From, class _To, class = void> +struct __is_convertible_test : public false_type {}; + +template <class _From, class _To> +struct __is_convertible_test<_From, _To, + decltype(__test_convert<_To>(_VSTD::declval<_From>()))> : public true_type +{}; + template <class _Tp> __two __test(...); #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES template <class _Tp> _Tp&& __source(); @@ -883,10 +892,8 @@ template <class _T1, class _T2, unsigned _T2_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T2>::value> struct __is_convertible : public integral_constant<bool, -#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES - sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1 -#else - sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1 + __is_convertible_imp::__is_convertible_test<_T1, _T2>::value +#if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !(!is_function<_T1>::value && !is_reference<_T1>::value && is_reference<_T2>::value && (!is_const<typename remove_reference<_T2>::type>::value || is_volatile<typename remove_reference<_T2>::type>::value) Modified: libcxx/trunk/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp?rev=233552&r1=233551&r2=233552&view=diff ============================================================================== --- libcxx/trunk/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp (original) +++ libcxx/trunk/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp Mon Mar 30 10:22:20 2015 @@ -186,4 +186,10 @@ int main() static_assert((std::is_convertible<volatile NonCopyable&, const volatile NonCopyable&>::value), ""); static_assert((std::is_convertible<const volatile NonCopyable&, const volatile NonCopyable&>::value), ""); static_assert((!std::is_convertible<const NonCopyable&, NonCopyable&>::value), ""); +// This test requires Access control SFINAE which we only have in C++11 or when +// we are using the compiler builtin for is_convertible. +#if __cplusplus >= 201103L || !defined(_LIBCPP_USE_IS_CONVERTIBLE_FALLBACK) + test_is_not_convertible<NonCopyable&, NonCopyable>(); +#endif + } _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
