Change size of reference count field in __libcpp_nmstr from 32 bits to 64 bits for 64 bit targets.  This is controls the data layout of all exceptions defined in <stdexcept>.  This aligns the ABI with that of gcc-4.2.
Change size of reference count field in __libcpp_nmstr from 32 bits to 64 bits for 64 bit targets.  This is controls the data layout of all exceptions defined in <stdexcept>.  This aligns the ABI with that of gcc-4.2.

git-svn-id: 756ef344af921d95d562d9e9f9389127a89a6314@161497 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx