diff -pruN 8.2.1+dfsg-2/debian/changelog 8.2.1+dfsg-2ubuntu1/debian/changelog
--- 8.2.1+dfsg-2/debian/changelog	2020-08-10 17:01:56.000000000 +0000
+++ 8.2.1+dfsg-2ubuntu1/debian/changelog	2020-10-06 18:54:51.000000000 +0000
@@ -1,3 +1,9 @@
+swi-prolog (8.2.1+dfsg-2ubuntu1) groovy; urgency=medium
+
+  * Omit libunwind-dev on riscv64 in addition to s390x.
+
+ -- Steve Langasek <steve.langasek@ubuntu.com>  Tue, 06 Oct 2020 11:54:51 -0700
+
 swi-prolog (8.2.1+dfsg-2) unstable; urgency=medium
 
   * Increase certificate expiry time and CRL refresh time to 3 years
diff -pruN 8.2.1+dfsg-2/debian/control 8.2.1+dfsg-2ubuntu1/debian/control
--- 8.2.1+dfsg-2/debian/control	2020-08-10 17:01:56.000000000 +0000
+++ 8.2.1+dfsg-2ubuntu1/debian/control	2020-10-06 18:54:51.000000000 +0000
@@ -1,7 +1,8 @@
 Source: swi-prolog
 Section: interpreters
 Priority: optional
-Maintainer: Lev Lamberov <dogsleg@debian.org>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+XSBC-Original-Maintainer: Lev Lamberov <dogsleg@debian.org>
 Build-Depends: cmake,
                dctrl-tools,
                debhelper-compat (= 13),
@@ -20,7 +21,7 @@ Build-Depends: cmake,
                libpcre3-dev,
                libreadline-dev,
                libssl-dev,
-               libunwind-dev [!s390x],
+               libunwind-dev [!s390x !riscv64],
                libx11-dev,
                libxext-dev,
                libxft-dev,