diff --git a/serving/external/exprtk b/serving/external/exprtk
index b0bc24cfd..806c519c9 160000
--- a/serving/external/exprtk
+++ b/serving/external/exprtk
@@ -1 +1 @@
-Subproject commit b0bc24cfdda39b30145b1f6c2c84b801cd131fef
+Subproject commit 806c519c91fd08ba4fa19380dbf3f6e42de9e2d1