Update library to 6.12.3

diff --git a/lib b/lib
index d94736d23b49e9b6653564cef67f96d028405c11..aec9e4131b092ed33213b9891e1dc2b9574edf99 160000 (submodule)
--- a/lib
+++ b/lib
@@ -1 +1 @@
-Subproject commit d94736d23b49e9b6653564cef67f96d028405c11
+Subproject commit aec9e4131b092ed33213b9891e1dc2b9574edf99