Update current namespace management by using control frames and lexical contexts

to fix inconsistent and wrong current namespace detections.

This includes:
* Moving load_path and related things from rb_vm_t to rb_namespace_t to simplify
  accessing those values via namespace (instead of accessing either vm or ns)
* Initializing root_namespace earlier and consolidate builtin_namespace into root_namespace
* Adding VM_FRAME_FLAG_NS_REQUIRE for checkpoints to detect a namespace to load/require files
* Removing implicit refinements in the root namespace which was used to determine
  the namespace to be loaded (replaced by VM_FRAME_FLAG_NS_REQUIRE)
* Removing namespaces from rb_proc_t because its namespace can be identified by lexical context
* Starting to use ep[VM_ENV_DATA_INDEX_SPECVAL] to store the current namespace when
  the frame type is MAGIC_TOP or MAGIC_CLASS (block handlers don't exist in this case)

1 files changed, 1 insertions, 1 deletions

diff --git a/class.c b/class.c
index b15f9f5ae7..e133d1579b 100644
--- a/class.c
+++ b/class.c
@@ -650,7 +650,7 @@ class_alloc0(enum ruby_value_type type, VALUE klass, bool namespaceable)
 {
     rb_ns_subclasses_t *ns_subclasses;
     rb_subclass_anchor_t *anchor;
-    const rb_namespace_t *ns = rb_definition_namespace();
+    const rb_namespace_t *ns = rb_current_namespace();
 
     if (!ruby_namespace_init_done) {
         namespaceable = true;