Reduce the size of `struct RBreak` to reduce memory usage.

The old size of `struct RBreak` was 56 bytes (`MRB_NO_BOXING`)
and it's bigger than other object structures. That increase the
size of `RVALUE` thus increase the total amount of memory consumption.

1 files changed, 0 insertions, 1 deletions

diff --git a/src/vm.c b/src/vm.c
index 170cb832d..2c2d74db1 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -810,7 +810,6 @@ break_new(mrb_state *mrb, struct RProc *p, mrb_value val)
   struct RBreak *brk;
 
   brk = (struct RBreak*)mrb_obj_alloc(mrb, MRB_TT_BREAK, NULL);
-  brk->iv = NULL;
   brk->proc = p;
   brk->val = val;