From 60dd6b55860a04dcb7fe3325fffb1fbd703e13b8 Mon Sep 17 00:00:00 2001
From: dearblue <dearblue@users.osdn.me>
Date: Mon, 29 Jan 2024 21:32:04 +0900
Subject: [PATCH] Allow to detect use-after-free after `mrb_irep_free()` for
 debugging

Write invalid value to `irep` if `MRB_DEBUG` is defined by `MRuby::Build#enable_debug`.
---
 src/state.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/state.c b/src/state.c
index ced96cb88..35ea71e2d 100644
--- a/src/state.c
+++ b/src/state.c
@@ -161,6 +161,9 @@ mrb_irep_free(mrb_state *mrb, mrb_irep *irep)
   }
   mrb_free(mrb, (void*)irep->lv);
   mrb_debug_info_free(mrb, irep->debug_info);
+#ifdef MRB_DEBUG
+  memset(irep, -1, sizeof(*irep));
+#endif
   mrb_free(mrb, irep);
 }