1 files changed, 11 insertions, 9 deletions

diff --git a/src/gc.c b/src/gc.c
index fa7f30889..be812c4d3 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -667,7 +667,6 @@ gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
 {
   mrb_assert(is_gray(obj));
   paint_black(obj);
-  gc->gray_list = obj->gcnext;
   mrb_gc_mark(mrb, (struct RBasic*)obj->c);
   switch (obj->tt) {
   case MRB_TT_ICLASS:
@@ -731,10 +730,11 @@ gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
   case MRB_TT_ARRAY:
     {
       struct RArray *a = (struct RArray*)obj;
-      size_t i, e;
+      size_t i, e=ARY_LEN(a);
+      mrb_value *p = ARY_PTR(a);
 
-      for (i=0,e=ARY_LEN(a); i<e; i++) {
-        mrb_gc_mark_value(mrb, ARY_PTR(a)[i]);
+      for (i=0; i<e; i++) {
+        mrb_gc_mark_value(mrb, p[i]);
       }
     }
     break;
@@ -1043,10 +1043,9 @@ gc_gray_counts(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
 static void
 gc_mark_gray_list(mrb_state *mrb, mrb_gc *gc) {
   while (gc->gray_list) {
-    if (is_gray(gc->gray_list))
-      gc_mark_children(mrb, gc, gc->gray_list);
-    else
-      gc->gray_list = gc->gray_list->gcnext;
+    struct RBasic *obj = gc->gray_list;
+    gc->gray_list = obj->gcnext;
+    gc_mark_children(mrb, gc, obj);
   }
 }
 
@@ -1058,6 +1057,7 @@ incremental_marking_phase(mrb_state *mrb, mrb_gc *gc, size_t limit)
 
   while (gc->gray_list && tried_marks < limit) {
     struct RBasic *obj = gc->gray_list;
+    gc->gray_list = obj->gcnext;
     gc_mark_children(mrb, gc, obj);
     tried_marks += gc_gray_counts(mrb, gc, obj);
   }
@@ -1076,7 +1076,9 @@ final_marking_phase(mrb_state *mrb, mrb_gc *gc)
   }
   mrb_gc_mark_gv(mrb);
   mark_context(mrb, mrb->c);
-  mark_context(mrb, mrb->root_c);
+  if (mrb->c != mrb->root_c) {
+    mark_context(mrb, mrb->root_c);
+  }
   mrb_gc_mark(mrb, (struct RBasic*)mrb->exc);
   gc_mark_gray_list(mrb, gc);
   mrb_assert(gc->gray_list == NULL);