If the TZ environment variable is not set, the time zone names
retrieved from the system are localized for UI display and may vary
across editions and language packs for the same time zone.
Use the time zone IDs that are invariant across environments instead.

	[Bug #20989] Ripper: Pass `compile_error`

	For the universal parser, `rb_parser_reg_fragment_check` function is
	shared between the parser and ripper.  However `parser_params` struct
	is partially different, and `compile_error` function depends on that
	part indirectly.

For the universal parser, `rb_reg_named_capture_assign_iter_impl`
function is shared between the parser and ripper.  However
`parser_params` struct is partially different, and `assignable`
function depends on that part indirectly.

This change poisons the whole slot of the object rather than just the flags.
This allows ASAN to find any reads/writes into the slot after it has been
freed.

Newer GCCs have __has_feature and older ones have
__SANITIZE_ADDRESS__[1]. Relevant since ASAN with GCC 11 on the popular
Ubuntu Jammy failed to build previously.

[1]: https://gcc.gnu.org/onlinedocs/gcc-4.8.0/cpp/Common-Predefined-Macros.html

When reference updating ObjectSpace.trace_object_allocations, we need to
check whether the object is valid or not because it does not mark the
object so the object may be dead. This can cause a segmentation fault
if the object is on a free heap page.

For example, the following script crashes:

    require "objspace"

    objs = []
    ObjectSpace.trace_object_allocations do
      1_000_000.times do
        objs << Object.new
      end
    end

    objs = nil

    # Free pages that the objs were on
    GC.start

    # Run compaction and check that it doesn't crash
    GC.compact

[Bug #20950]

ifunc proc has the ep allocated in the cfunc_proc_t which is the data of
the TypedData object. If an ifunc proc is duplicated, the ep points to
the ep of the source object. If the source object is freed, then the ep
of the duplicated object now points to a freed memory region. If we try
to use the ep we could crash.

For example, the following script crashes:

    p = { a: 1 }.to_proc
    100.times do
      p = p.dup
      GC.start
      p.call
    rescue ArgumentError
    end

This commit changes ifunc proc to also duplicate the ep when it is duplicated.