merge revision(s) fb4cf204a662a8cd9dafef6f31f2bd0db9129abe,fa0279d947c3962c3f8c32852278d3ebb964cb19: [Backport #17725]

	use me->def instead of me for opt_table

	`vm_opt_method_table` is me=>bop table to manage the optimized
	methods (by specialized instruction). However, `me` can be invalidated
	to invalidate the method cache entry.
	[Bug #17725]

	To solve the issue, use `me-def` instead of `me` which simply copied
	at invalidation timing.

	A test by @jeremyevans https://github.com/ruby/ruby/pull/4376
	---
	 test/ruby/test_method.rb | 15 +++++++++++++++
	 vm.c                     | 11 +++++------
	 2 files changed, 20 insertions(+), 6 deletions(-)

	should not share same `def` for specialized method

	Because the key of redefine table is `def`, `def` should be
	unique for each optimized method (`alias` is not allowed).
	---
	 array.c | 2 +-
	 1 file changed, 1 insertion(+), 1 deletion(-)

1 files changed, 1 insertions, 1 deletions

diff --git a/array.c b/array.c
index 6993796854..b48a6431e7 100644
--- a/array.c
+++ b/array.c
@@ -8122,7 +8122,7 @@ Init_Array(void)
     rb_define_method(rb_cArray, "each_index", rb_ary_each_index, 0);
     rb_define_method(rb_cArray, "reverse_each", rb_ary_reverse_each, 0);
     rb_define_method(rb_cArray, "length", rb_ary_length, 0);
-    rb_define_alias(rb_cArray,  "size", "length");
+    rb_define_method(rb_cArray, "size", rb_ary_length, 0);
     rb_define_method(rb_cArray, "empty?", rb_ary_empty_p, 0);
     rb_define_method(rb_cArray, "find_index", rb_ary_index, -1);
     rb_define_method(rb_cArray, "index", rb_ary_index, -1);