From fae8e553968a48972013b317b2b252321e9d7c91 Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Sat, 7 Oct 2023 22:39:28 +0900
Subject: [PATCH] pool.c (mrb_pool_realloc): add comments in reallocation code

---
 src/pool.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/pool.c b/src/pool.c
index 067ec68a8..dbf133677 100644
--- a/src/pool.c
+++ b/src/pool.c
@@ -139,8 +139,12 @@ mrb_pool_realloc(mrb_pool *pool, void *p, size_t oldlen, size_t newlen)
     if (page->last == p) {
       /* if p is a last allocation from the page */
       size_t beg = (char*)p - page->page;
+      /* check beg + oldlen points bottom */
+      /* assert(beg + oldlen == page->offset) */
       if (beg + oldlen != page->offset) break;
       if (beg + newlen > page->len) {
+        /* new allocation need more space */
+        /* abandon this space */
         page->offset = beg;
         break;
       }