commit 301518c94ec67e1f3a6147bc9a27256db2712644
author Eric Fiselier <eric@efcs.ca> Tue Jun 05 22:32:52 2018 +0000
committer Eric Fiselier <eric@efcs.ca> Tue Jun 05 22:32:52 2018 +0000
tree 2084374413acd3b00f74de3ac75a54c49f1632d2
parent 55513c8efb03a53bc9e87d1eba727f8a15c1ed4d

Fix PR37694 - std::vector doesn't correctly move construct allocators.

C++2a[container.requirements.general]p8 states that when move constructing
a container, the allocator is move constructed. Vector previously copy
constructed these allocators. This patch fixes that bug.

Additionally it cleans up some unnecessary allocator conversions
when copy constructing containers. Libc++ uses
__internal_allocator_traits::select_on_copy_construction to select
the correct allocator during copy construction, but it unnecessarily
converted the resulting allocator to the user specified allocator
type and back. After this patch list and forward_list no longer
do that.

Technically we're supposed to be using allocator_traits<allocator_type>::select_on_copy_construction,
but that should seemingly be addressed as a separate patch, if at all.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@334053 91177308-0d34-0410-b5e6-96231b3b80d8