From 9803259cab1159cec0debf48aef45911c7dc3cfe Mon Sep 17 00:00:00 2001
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 =?UTF-8?q?=D0=B5=D0=B2=20=28Leonid=20Yuriev=29?= <leo@yuriev.ru>
Date: Fri, 13 Dec 2024 08:16:04 +0300
Subject: [PATCH] =?UTF-8?q?mdbx:=20=D0=B2=D0=BE=D0=B7=D0=B2=D1=80=D0=B0?=
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---
 src/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core.c b/src/core.c
index 35aff4b9..efbf4038 100644
--- a/src/core.c
+++ b/src/core.c
@@ -9285,7 +9285,7 @@ int mdbx_txn_begin_ex(MDBX_env *env, MDBX_txn *parent, MDBX_txn_flags_t flags,
   *ret = NULL;
 
   if (unlikely((flags & ~MDBX_TXN_RW_BEGIN_FLAGS) &&
-               (flags & ~MDBX_TXN_RO_BEGIN_FLAGS)))
+               (parent || (flags & ~MDBX_TXN_RO_BEGIN_FLAGS))))
     return MDBX_EINVAL;
 
   int rc = check_env(env, true);