GitLab

std::is_trivially_copyable should return false for classes with nontrivial
destructors.

C++11 standard section 9.6 says a trivially copyable class is a class that:
  — has no non-trivial copy constructors (12.8),
  — has no non-trivial move constructors (12.8),
  — has no non-trivial copy assignment operators (13.5.3, 12.8),
  — has no non-trivial move assignment operators (13.5.3, 12.8), and
  — has a trivial destructor (12.4).

The current implementation for _GNUC_VER < 501 didn't detech the destructor
case. This is important because when is_trivially_copyable returns true,
container code may implement moves as memcpy, when in fact it needs to me a
memcpy + a destructor.

Bug: 
Change-Id: I5739856ca7eaf5ddcf3eeb716bdc2dc33b0de0f2
Reviewed-on: https://chromium-review.googlesource.com/575020Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Brett Wilson <brettw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487237}