diff --git a/apron.spec b/apron.spec
index 6659d4c..4ecb444 100644
--- a/apron.spec
+++ b/apron.spec
@@ -1,6 +1,6 @@
 Name:           apron
 Version:        0.9.13
-Release:        5%{?dist}
+Release:        6%{?dist}
 Summary:        Numerical abstract domain library
 
 # The entire package is LGPLv2+ except newpolka/mf_qsort.c and ppl/*, all of
@@ -232,6 +232,9 @@ test/ctest1
 %{_jnidir}/*.so
 
 %changelog
+* Mon Oct 04 2021 Richard W.M. Jones <rjones@redhat.com> - 0.9.13-6
+- OCaml 4.13.1 build
+
 * Wed Jul 21 2021 Fedora Release Engineering <releng@fedoraproject.org> - 0.9.13-5
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_35_Mass_Rebuild