diff --git a/src/plugins/region/dune b/src/plugins/region/dune
index d9304aea10394da6bc7bf91e6182214ff82fe820..5ec040bf5c2c9ed4a0652916e190b43ddf451ada 100644
--- a/src/plugins/region/dune
+++ b/src/plugins/region/dune
@@ -32,7 +32,7 @@
 (library
   (name Region)
   (public_name frama-c-region.core)
-  (flags -open Frama_c_kernel :standard)
+  (flags -open Frama_c_kernel :standard -w -9)
   (libraries frama-c.kernel unionFind)
   (instrumentation (backend landmarks))
   (instrumentation (backend bisect_ppx)))