From f425e98eb5f0e56b6b5a9cd1314e7eb5016de3dd Mon Sep 17 00:00:00 2001
From: Leo Yuriev <leo@yuriev.ru>
Date: Fri, 6 Jul 2018 15:25:14 +0300
Subject: [PATCH] mdbx: fix  mdbx_env_compact().

Change-Id: Ie269b45c3d0325cb1b2d82f4ed1c18f8b3fe4212
---
 src/mdbx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mdbx.c b/src/mdbx.c
index 526c5053..2ba38d26 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -10446,8 +10446,8 @@ static int __cold mdbx_env_compact(MDBX_env *env, mdbx_filehandle_t fd) {
 
   /* update signature */
   meta->mp_meta.mm_datasync_sign = mdbx_meta_sign(&meta->mp_meta);
+  memcpy(ctx.mc_wbuf[0], buffer, ctx.mc_wlen[0] = pgno2bytes(env, NUM_METAS));
 
-  ctx.mc_wlen[0] = pgno2bytes(env, NUM_METAS);
   ctx.mc_txn = txn;
   rc = mdbx_env_cwalk(&ctx, &root, 0);
   if (rc == MDBX_SUCCESS && root != new_root) {