Fix a couple of failing tests for C++03 by checking for rvalue reference support first.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220465 91177308-0d34-0410-b5e6-96231b3b80d8
Add support for "fancy" pointers to shared_ptr. Fixes PR20616

Summary:
This patch add support for "fancy pointers/allocators" as well as fixing support for shared_pointer and "minimal" allocators.

Fancy pointers are class types that meet the NullablePointer requirements. In our case they are created by fancy allocators. `support/min_allocator.h` is an archetype for these types.

There are three types of changes made in this patch:
1. `_Alloc::template rebind<T>::other` -> `__allocator_traits_rebind<_Alloc, T>::type`. This change was made because allocators don't need a rebind template. `__allocator_traits_rebind` is used instead of `allocator_traits::rebind` because use of `allocator_traits::rebind` requires a workaround for when template aliases are unavailable.
2. `a.deallocate(this, 1)` -> `a.deallocate(pointer_traits<self>::pointer_to(*this), 1)`. This change change is made because fancy pointers aren't always constructible from raw pointers. 
3. `p.get()` -> `addressof(*p.get())`. Fancy pointers aren't actually a pointer. When we need a "real" pointer we take the address of dereferencing the fancy pointer. This should give us the actual raw pointer.

Test Plan: Tests were added using `support/min_allocator.h` to each affected shared_ptr overload and creation function. These tests can only be executed in C++11 or greater since min_allocator is only available then. A extra test was added for the non-variadic versions of allocate_shared. 

Reviewers: danalbert, mclow.lists

Reviewed By: mclow.lists

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D4859

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220469 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxx
Add support for "fancy" pointers to promise and packaged_task.

Summary:
This patch is very closely related to D4859. Please see http://reviews.llvm.org/D4859 for more information.

This patch adds support for "fancy" pointers and allocators to promise and packaged_task. The changes made to support this are exactly the same as in D4859.



Test Plan: "fancy" pointer tests were added to each constructor affected by the change.

Reviewers: danalbert, mclow.lists

Reviewed By: mclow.lists

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D4862

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220471 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxx
Make headers available in the build directory

This essentially re-does r194825 and makes it possible to run clang
with libc++ without having to install it, even if you don't have any
version of libc++ installed in /usr/.

This behaviour broke in r210577/r211629, which fixed pr18681.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220489 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxx
Only link tests against -ldl on linux

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220510 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxx