Version 4.15

This version completes our C++17 support.

The following additional C++17 features are now supported:
	- Template argument deduction for class templates
	- Declaring non-type template parameters with auto
	- Guaranteed copy elision
	- Stricter expression evaluation order
	- Pack expansions in using-declarations
	- Extended matching of template template arguments
	- Extensions to aggregate initialization
	- Qualification conversions and pointers to arrays of pointers
	- Constant evaluation for all non-type template arguments

Still to be completed as of the beta:
        - Rewording inheriting constructors

[ Version updates here? ]
The builtin function support incorporates changes in the GCC builtin function
signatures through GCC version 6.4 (for the GCC 6.x versions) and GCC version
7.2 (for the GCC 7.x versions), and in the clang builtin function signatures
as of clang 4.0.1.

As usual, we have fixed bugs, added many minor features, and continued to
improve our various compatibility modes.  See the Changes_4.14 file for
full details (about 3,000 lines).

This release includes new target-dependent variables.  If you are using
run-time target configurations (other than the default ones we provide), you
will need to update those to include new target-specific configuration macros
with appropriate values for each of your target configurations.  The new
target configuration variables are:

    [ I don't think there are any at this point ]

Note that if you do not provide the necessary configuration macros, you
will get build errors along the lines of "TARG_XXX_my_config undefined".


TARG_IA64_ABI_USE_GUARD_ACQUIRE_RELEASE
TARG_IA64_ABI_USE_INT_STATIC_INIT_GUARD
TARG_IA64_ABI_USE_VARIANT_ARRAY_COOKIES
TARG_IA64_ABI_USE_VARIANT_PTR_TO_MEMBER_FUNCTION_REPR
TARG_IA64_ABI_VARIANT_CTORS_AND_DTORS_RETURN_THIS
TARG_IA64_ABI_VARIANT_KEY_FUNCTION
