Author: dim
Date: Mon Apr 6 14:50:54 2015
New Revision: 281149
URL: https://svnweb.freebsd.org/changeset/base/281149
Log:
MFC r280864:
Pull in r233552 from upstream libc++ trunk (by Eric Fiselier):
[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
This fixes building clang, and other programs using libc++, with newer
versions of gcc (specifically, gcc 4.8 and higher).
Reported by: rodrigc
Modified:
stable/9/contrib/libc++/include/type_traits
Directory Properties:
stable/9/ (props changed)
stable/9/contrib/ (props changed)
stable/9/contrib/libc++/ (props changed)
Changes in other areas also in this revision:
Modified:
stable/10/contrib/libc++/include/type_traits
Directory Properties:
stable/10/ (props changed)
Modified: stable/9/contrib/libc++/include/type_traits
==============================================================================
--- stable/9/contrib/libc++/include/type_traits Mon Apr 6 14:45:40 2015 (r281148)
+++ stable/9/contrib/libc++/include/type_traits Mon Apr 6 14:50:54 2015 (r281149)
@@ -842,7 +842,16 @@ 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();
@@ -877,10 +886,8 @@ 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)