This is an initial commit of constexpr support as proposed by Richard Smith.  This by no means completes constexpr support.  Indeed, it hardly scratches the surface.  All it does is lay the foundation in <__config> and changes those few places in the library that are already using that foundation.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@153856 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed