Fix crash in method call in `ObjectSpace.each_object` block.

* Filter `MRB_TT_ENV` and `MRB_TT_ICLASS`.
* Set `mrb->string_class` in `mrb_init_exception` instead.

1 files changed, 7 insertions, 0 deletions

diff --git a/mrbgems/mruby-objectspace/src/mruby_objectspace.c b/mrbgems/mruby-objectspace/src/mruby_objectspace.c
index ba22fc990..8c7452c1e 100644
--- a/mrbgems/mruby-objectspace/src/mruby_objectspace.c
+++ b/mrbgems/mruby-objectspace/src/mruby_objectspace.c
@@ -119,6 +119,13 @@ os_each_object_cb(mrb_state *mrb, struct RBasic *obj, void *ud)
     return;
   }
 
+  /* filter internal objects */
+  switch (obj->tt) {
+  case MRB_TT_ENV:
+  case MRB_TT_ICLASS:
+    return;
+  }
+
   /* filter class kind if target module defined */
   if (d->target_module && !mrb_obj_is_kind_of(mrb, mrb_obj_value(obj), d->target_module)) {
     return;