[PATCH] [Bug #21638] Mark ractor-local `$VERBOSE` and `$DEBUG`

	https://github.com/sampersand/blog/blob/master/the%20-s%20flag.md#the-segfault

	[PATCH] load.c: Fix dest and src of MEMMOVE

	When multiple files with the same name are required, the features_index
	hash stores the indexes in `$LOADED_FEATURES` array into a darray.
	The dest and src arguments for `MEMMOVE` were wrongly reversed when
	inserting a new index in the darray.

	[Bug #21568]

	Message not found for revision: 62430c19c9f1ab49429cebe65f30588472648c95

	Fix crash when $LOADED_FEATURES is modified during require

	[Bug #21567]

	When we require an object that is not a string, it will attempt to convert
	it to a string by calling to_str on it. If we modify the $LOADED_FEATURES
	array while it calls to_str, Ruby can crash because it can end up inserting
	the string in the wrong index in the array.

	For example, the following script crashes:

	    require "tempfile"

	    class MyString
	      def initialize(path)
	        @path = path
	      end

	      def to_str
	        $LOADED_FEATURES.clear
	        @path
	      end

	      def to_path = @path
	    end

	    def create_ruby_file = Tempfile.create(["test", ".rb"]).path

	    require MyString.new(create_ruby_file)
	    $LOADED_FEATURES.unshift(create_ruby_file)
	    $LOADED_FEATURES << MyString.new(create_ruby_file)
	    require create_ruby_file

	Crash log:

	    test.rb:21: [BUG] Segmentation fault at 0x0000000000000004
	    ruby 3.5.0dev (2025-09-09T09:29:35Z master ce94add7fb) +PRISM [arm64-darwin24]

	    -- Crash Report log information --------------------------------------------
	      See Crash Report log file in one of the following locations:
	        * ~/Library/Logs/DiagnosticReports
	        * /Library/Logs/DiagnosticReports
	      for more details.
	    Don't forget to include the above Crash Report log file in bug reports.

	    -- Control frame information -----------------------------------------------
	    c:0003 p:---- s:0011 e:000010 CFUNC  :require
	    c:0002 p:0076 s:0006 e:000005 EVAL   test.rb:21 [FINISH]
	    c:0001 p:0000 s:0003 E:0001b0 DUMMY  [FINISH]

	    -- Ruby level backtrace information ----------------------------------------
	    test.rb:21:in '<main>'
	    test.rb:21:in 'require'

	    -- Threading information ---------------------------------------------------
	    Total ractor count: 1
	    Ruby thread count for this ractor: 1

	    -- Machine register context ------------------------------------------------
	      x0: 0x0000000000000004  x1: 0x000000000000c800  x2: 0x0000000000000000
	      x3: 0x0000000000000000  x4: 0x0000000000000205  x5: 0x0000000000000000
	      x6: 0x0000000000000000  x7: 0x0000000000000001 x18: 0x0000000000000000
	    x19: 0x0000000209dfc0b0 x20: 0x0000000209dfc018 x21: 0x000000016ee8ab58
	    x22: 0x0fffffff0009d71d x23: 0x0000000209dfc018 x24: 0x0000000209dfc150
	    x25: 0x000000016ee8acc0 x26: 0x0000000000000000 x27: 0x0000000000000000
	    x28: 0x0000000000000000  lr: 0x0000000101244140  fp: 0x000000016ee887f0
	      sp: 0x000000016ee887d0

	    -- C level backtrace information -------------------------------------------
	    miniruby(rb_print_backtrace+0x24) [0x101317b08] vm_dump.c:843
	    miniruby(rb_print_backtrace) (null):0
	    miniruby(rb_vm_bugreport+0x26c) [0x101317d94] vm_dump.c:1175
	    miniruby(rb_bug_for_fatal_signal+0xa4) [0x10105ddac] error.c:1130
	    miniruby(sig_do_nothing+0x0) [0x1012278c0] signal.c:948
	    miniruby(sigsegv) (null):0
	    /usr/lib/system/libsystem_platform.dylib(_sigtramp+0x38) [0x19c1216a4]
	    miniruby(rb_str_new_frozen+0x1c) [0x101244140] string.c:1495
	    miniruby(rb_check_realpath_internal+0x68) [0x101077804] file.c:4679
	    miniruby(rb_check_realpath+0x2c) [0x101077aa4] file.c:4765
	    miniruby(get_loaded_features_index+0x37c) [0x1010f9c94] load.c:467
	    miniruby(rb_feature_p+0xd0) [0x1010f8174] load.c:582
	    miniruby(search_required+0xac) [0x1010f6ad4] load.c:1193
	    miniruby(require_internal+0x274) [0x1010f7518] load.c:1424
	    miniruby(rb_require_string_internal+0x94) [0x1010f6830] load.c:1571
	    miniruby(rb_require_string+0x58) [0x1010f66e8] load.c:1557
	    miniruby(rb_f_require+0x1c) [0x1010f6684] load.c:1150
	    miniruby(ractor_safe_call_cfunc_1+0x38) [0x101306c28] vm_insnhelper.c:3696
	    miniruby(vm_call_cfunc_with_frame_+0x250) [0x1012f857c] vm_insnhelper.c:3873
	    miniruby(vm_call_cfunc_with_frame+0x6c) [0x1012f8834] vm_insnhelper.c:3919
	    miniruby(vm_sendish+0x1a8) [0x1012c990c] vm_insnhelper.c:6087
	    miniruby(vm_exec_core+0x4050) [0x1012cfb48] insns.def:900
	    miniruby(vm_exec_loop+0x80) [0x1012e5448] vm.c:2666
	    miniruby(rb_vm_exec+0x134) [0x1012c9b40] vm.c:2645
	    miniruby(rb_iseq_eval_main+0x34) [0x1012e5628] vm.c:2919
	    miniruby(rb_ec_exec_node+0xe4) [0x10106d094] eval.c:282
	    miniruby(ruby_run_node+0x94) [0x10106cf64] eval.c:320
	    miniruby(rb_main+0x40) [0x100f7499c] main.c:42
	    miniruby(main+0x60) [0x100f74928] main.c:62

	ruby2_keywords warnings: Quote non-UTF8 method names fully

	It used to quote only part of the method name because NUL byte in
	the method terminates the C string:

	```
	(irb)> "abcdef".encode("UTF-16LE").bytes
	=> [97, 0, 98, 0, 99, 0, 100, 0, 101, 0, 102, 0]
	```

	```
	expected: /abcdef/
	actual: warning: Skipping set of ruby2_keywords flag for a (method not defined in Ruby)\n".
	```

	Do not respect ruby2_keywords on method/proc with post arguments

	Previously, ruby2_keywords could be used on a method or proc with
	post arguments, but I don't think the behavior is desired:

	```ruby
	def a(*c, **kw) [c, kw] end
	def b(*a, b) a(*a, b) end
	ruby2_keywords(:b)

	b({foo: 1}, bar: 1)
	```

	This changes ruby2_keywords to emit a warning and not set the
	flag on a method/proc with post arguments.

	While here, fix the ruby2_keywords specs for warnings, since they
	weren't testing what they should be testing.  They all warned
	because the method didn't accept a rest argument, not because it
	accepted a keyword or keyword rest argument.

	[Bug #20009] Support marshaling non-ASCII name class/module

[Bug #21438]

Previously GC could trigger a table rebuild of the generic ivar
st_table in the middle of calling the st_update callback. This could
cause entries to be reallocated or rearranged and the update to be for
the wrong entry.

This commit adds an assertion to make that case easier to detect, and
replaces the st_update with a separate st_lookup and st_insert.

Also free after insert in generic_ivar_set_shape_ivptr

Previously we were performing a realloc and then inserting the new value
into the table. If the table was flagged as requiring a rebuild, this
could trigger GC work and marking within that GC could access the ivptr
freed by realloc.

Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>
Co-authored-by: Jean Boussier <byroot@ruby-lang.org>