PR65122 extended alignment support in allocators

PR65122 extended alignment support in allocators

	PR libstdc++/65122
	* include/ext/malloc_allocator.h (malloc_allocator::allocate): Use
	aligned_alloc for types with extended alignment if available,
	otherwise throw bad_alloc if malloc doesn't return a suitable value.
	* include/ext/bitmap_allocator.h (bitmap_allocator::allocate)
	(bitmap_allocator::deallocate): Use aligned new/delete for types with
	extended alignment.
	* include/ext/mt_allocator.h (__mt_alloc::allocate)
	(__mt_alloc::deallocate): Likewise.
	* include/ext/new_allocator.h (new_allocator::allocate)
	(new_allocator::deallocate): Likewise.
	* include/ext/pool_allocator.h (__pool_alloc::allocate)
	(__pool_alloc::deallocate): Likewise.
	* testsuite/20_util/allocator/overaligned.cc: New test.
	* testsuite/ext/bitmap_allocator/overaligned.cc: New test.
	* testsuite/ext/malloc_allocator/overaligned.cc: New test.
	* testsuite/ext/mt_allocator/overaligned.cc: New test.
	* testsuite/ext/new_allocator/overaligned.cc: New test.
	* testsuite/ext/pool_allocator/overaligned.cc: New test.

From-SVN: r241158