Support overaligned types in `aligned_storage`.

Summary:
The current implementation of aligned storage was written before we had `alignas`, so it used a list of builtin types to force the alignment. But this doesn't work overaligned requests.

This patch adds a fallback case supporting over-alignment. It only affects case that were previously ill-formed.

Reviewers: rsmith, ldionne, dlj, mclow.lists

Reviewed By: mclow.lists

Subscribers: mclow.lists, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D61301

llvm-svn: 359596

1 files changed, 8 insertions, 0 deletions

diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
index 0b4aac31580..e7615329598 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
@@ -285,6 +285,14 @@ int main(int, char**)
     static_assert(std::alignment_of<T1>::value == 8, "");
     static_assert(sizeof(T1) == 16, "");
     }
+  {
+    const int Align = 65536;
+    typedef typename std::aligned_storage<1, Align>::type T1;
+    static_assert(std::is_trivial<T1>::value, "");
+    static_assert(std::is_standard_layout<T1>::value, "");
+    static_assert(std::alignment_of<T1>::value == Align, "");
+    static_assert(sizeof(T1) == Align, "");
+  }
 
   return 0;
 }