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From: "janezz55 at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/58109] New: alignas() fails to compile with constant expression Date: Fri, 09 Aug 2013 12:37:00 -0000 [thread overview] Message-ID: <bug-58109-4@http.gcc.gnu.org/bugzilla/> (raw) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58109 Bug ID: 58109 Summary: alignas() fails to compile with constant expression Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: janezz55 at gmail dot com Created attachment 30626 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30626&action=edit file demonstrating bug The following example compiles without issue with clang++ 3.3: #include <cassert> #include <string> #include <type_traits> #include <typeinfo> #include <utility> namespace detail { template <typename A, typename ...B> struct max_align : std::integral_constant<std::size_t, (alignof(A) > max_align<B...>{}) ? alignof(A) : max_align<B...>{}> { }; template <typename A, typename B> struct max_align<A, B> : std::integral_constant<std::size_t, (alignof(A) > alignof(B)) ? alignof(A) : alignof(B)> { }; template <typename A> struct max_align<A> : std::integral_constant<std::size_t, alignof(A)> { }; }; template <typename ...T> struct test { alignas(::detail::max_align<T...>::value) char store_[10]; }; int main() { test<std::string, int> a; return 0; } But even with g++-4.9, it fails with: t.cpp:39:59: error: requested alignment is not an integer constant alignas(::detail::max_align<T...>::value) char store_[10];
next reply other threads:[~2013-08-09 12:37 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-08-09 12:37 janezz55 at gmail dot com [this message] 2013-08-09 12:59 ` [Bug c++/58109] " paolo.carlini at oracle dot com 2013-08-09 13:02 ` janezz55 at gmail dot com 2013-08-09 13:06 ` paolo.carlini at oracle dot com 2013-11-05 22:16 ` paolo.carlini at oracle dot com 2021-09-20 22:01 ` pinskia at gcc dot gnu.org
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