diff -pruN 8.4.2+dfsg-2/debian/changelog 8.4.2+dfsg-2ubuntu1/debian/changelog
--- 8.4.2+dfsg-2/debian/changelog	2022-02-20 09:50:30.000000000 +0000
+++ 8.4.2+dfsg-2ubuntu1/debian/changelog	2022-02-28 22:59:14.000000000 +0000
@@ -1,3 +1,10 @@
+swi-prolog (8.4.2+dfsg-2ubuntu1) jammy; urgency=low
+
+  * Merge from Debian unstable. Remaining changes:
+    - Omit libunwind-dev on riscv64 in addition to s390x.
+
+ -- Michael Hudson-Doyle <michael.hudson@ubuntu.com>  Tue, 01 Mar 2022 11:59:14 +1300
+
 swi-prolog (8.4.2+dfsg-2) unstable; urgency=medium
 
   * Add patch to handle ODBC on 32-bit platforms.
@@ -14,6 +21,13 @@ swi-prolog (8.4.2+dfsg-1) unstable; urge
 
  -- Lev Lamberov <dogsleg@debian.org>  Tue, 15 Feb 2022 20:56:47 +0500
 
+swi-prolog (8.2.4+dfsg-1ubuntu1) hirsute; urgency=low
+
+  * Merge from Debian unstable. Remaining changes:
+    - Omit libunwind-dev on riscv64 in addition to s390x.
+
+ -- Dimitri John Ledkov <xnox@ubuntu.com>  Tue, 02 Mar 2021 04:51:58 +0000
+
 swi-prolog (8.2.4+dfsg-1) unstable; urgency=medium
 
   * New upstream version 8.2.4+dfsg
@@ -78,6 +92,12 @@ swi-prolog (8.2.2+dfsg-1) unstable; urge
 
  -- Lev Lamberov <dogsleg@debian.org>  Thu, 29 Oct 2020 12:28:15 +0500
 
+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 8.4.2+dfsg-2/debian/control 8.4.2+dfsg-2ubuntu1/debian/control
--- 8.4.2+dfsg-2/debian/control	2022-02-20 09:50:30.000000000 +0000
+++ 8.4.2+dfsg-2ubuntu1/debian/control	2022-02-21 20:06:12.000000000 +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,
