Revert r216497: "[libcxx] Fix ctype_byname<wchar_t>::do_is() mask checking."

After discussing implementing more tests for this with @danalbert & @mclow, I
realized this change is not correct.

The C++ standard requires do_is() to behave as if it were a loop that checked
is(). Furthermore, it requires is() to check "The first form returns the result
of the expression (M & m) != 0; i.e., true if the character has the
characteristics specified"... which the reverted patch definitely does not
conform to. Even further, furthermore, this requires that ctype's mask be an
actual bitmask, unlike what android and newlib provide for _ctype_.

Fixing the original bug that instigated this patch remains TBD.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@216508 91177308-0d34-0410-b5e6-96231b3b80d8
Rename arguments in include/cmath to work around Newlib macro implementation using these particular names

http://reviews.llvm.org/D5080


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@216548 91177308-0d34-0410-b5e6-96231b3b80d8
Mark test types for <atomic> nothrow default constructible. Patch from Steve MacKenzie.

The way the standard currently specifies the default constructor for atomic<T>
requires T to be nothrow default constructible. This patch makes our test types
meet this requirement.

Note: The nothrow default constructible requirment is subject to the outcome of
LWG issue 1265.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@216561 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxx