1 files changed, 2 insertions, 1 deletions
diff --git a/src/os_unix.c b/src/os_unix.c
index 53a4fd31b..fb2a8ca91 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -4660,7 +4660,8 @@ static void unixShmBarrier(
   sqlite3_file *fd                /* Database file holding the shared memory */
 ){
   UNUSED_PARAMETER(fd);
-  unixEnterMutex();
+  sqlite3MemoryBarrier();         /* compiler-defined memory barrier */
+  unixEnterMutex();               /* Also mutex, for redundancy */
   unixLeaveMutex();
 }