Eagerly name modules and classes

* variable.c: make the hidden ivars `classpath` and `tmp_classpath` the source
  of truth for module and constant names. Assign to them when modules are bind
  to constants.

* variable.c: remove references to module name cache, as what used to be the cache
  is now the source of truth. Remove rb_class_path_no_cache().

* variable.c: remove the hidden ivar `classid`. This existed for the purposes of
  module name search, which is now replaced. Also, remove the associated
  rb_name_class().

* class.c: use rb_set_class_path_string to set the name of Object during boot.
  Must use a fstring as this runs before rb_cString is initialized and
  creating a normal string leads to a VALUE without a class.

* spec/ruby/core/module/name_spec.rb: add a few specs to specify what happens
  to Module#name across multiple operations. These specs pass without other
  code changes in this commit.

[Feature #15765]

1 files changed, 1 insertions, 3 deletions

diff --git a/vm.c b/vm.c
index 9b6600393c..1bc1ed757f 100644
--- a/vm.c
+++ b/vm.c
@@ -374,8 +374,6 @@ rb_vm_inc_const_missing_count(void)
     ruby_vm_const_missing_count +=1;
 }
 
-VALUE rb_class_path_no_cache(VALUE _klass);
-
 MJIT_FUNC_EXPORTED int
 rb_dtrace_setup(rb_execution_context_t *ec, VALUE klass, ID id,
 		struct ruby_dtrace_method_hook_args *args)
@@ -395,7 +393,7 @@ rb_dtrace_setup(rb_execution_context_t *ec, VALUE klass, ID id,
     }
     type = BUILTIN_TYPE(klass);
     if (type == T_CLASS || type == T_ICLASS || type == T_MODULE) {
-	VALUE name = rb_class_path_no_cache(klass);
+	VALUE name = rb_class_path(klass);
 	const char *classname, *filename;
 	const char *methodname = rb_id2name(id);
 	if (methodname && (filename = rb_source_location_cstr(&args->line_no)) != 0) {