add Fiber.current

1 files changed, 2 insertions, 1 deletions

diff --git a/src/gc.c b/src/gc.c
index 361024af3..ccd925da8 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -619,7 +619,8 @@ obj_free(mrb_state *mrb, struct RBasic *obj)
     {
       struct mrb_context *c = ((struct RFiber*)obj)->cxt;
 
-      mrb_free_context(mrb, c);
+      if (c != mrb->root_c)
+        mrb_free_context(mrb, c);
     }
     break;