Fix std::pair on FreeBSD
Summary:
FreeBSD ships an old ABI for std::pair which requires that it have non-trivial copy/move constructors. Currently the non-trivial copy/move is achieved by providing explicit definitions of the constructors. This is problematic because it means the constructors don't SFINAE properly. In order to SFINAE copy/move constructors they have to be explicitly defaulted and hense non-trivial.
This patch attempts to provide SFINAE'ing copy/move constructors for std::pair while still making them non-trivial. It does this by adding a base class with a non-trivial copy constructor and then allowing pair's constructors to be generated by the compiler. This also allows the constructors to be constexpr.
Reviewers: emaste, theraven, rsmith, dim
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25389
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@283944 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed