diff --git a/baselibs.conf b/baselibs.conf
index 02051ec..604004b 100644
--- a/baselibs.conf
+++ b/baselibs.conf
@@ -1,4 +1,4 @@
-libisl22
+libisl23
 isl-devel
   requires -isl-<targettype>
-  requires "libisl22-<targettype> = <version>"
+  requires "libisl23-<targettype> = <version>"
diff --git a/isl-0.22.1.tar.xz b/isl-0.22.1.tar.xz
deleted file mode 100644
index 4ff8e74..0000000
--- a/isl-0.22.1.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:28658ce0f0bdb95b51fd2eb15df24211c53284f6ca2ac5e897acc3169e55b60f
-size 1676948
diff --git a/isl-0.23.tar.xz b/isl-0.23.tar.xz
new file mode 100644
index 0000000..4b8ca8f
--- /dev/null
+++ b/isl-0.23.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:5efc53efaef151301f4e7dde3856b66812d8153dede24fab17673f801c8698f2
+size 1729656
diff --git a/isl.changes b/isl.changes
index 7db5b8d..ec5fe2d 100644
--- a/isl.changes
+++ b/isl.changes
@@ -1,3 +1,12 @@
+-------------------------------------------------------------------
+Tue Dec 29 17:29:04 UTC 2020 - Dirk Müller <dmueller@suse.com>
+
+- update to 0.23:
+  - minor improvements to coalescing
+  - use build compiler to build extract_interface
+  - add some convenience functions
+  - ignore parameters in isl_union_* hash tables 
+
 -------------------------------------------------------------------
 Thu Feb  6 09:22:41 UTC 2020 - Martin Liška <mliska@suse.cz>
 
diff --git a/isl.spec b/isl.spec
index 611a8b7..01db485 100644
--- a/isl.spec
+++ b/isl.spec
@@ -16,19 +16,18 @@
 #
 
 
-%define islsover 22
+%define islsover 23
 Name:           isl
-Version:        0.22.1
+Version:        0.23
 Release:        0
 Summary:        Integer Set Library
 License:        MIT
 Group:          Development/Languages/C and C++
-URL:            http://isl.gforge.inria.fr/
+URL:            https://isl.gforge.inria.fr/
 Source:         http://isl.gforge.inria.fr/isl-%{version}.tar.xz
 Source1:        baselibs.conf
 BuildRequires:  gmp-devel
 BuildRequires:  pkgconfig
-BuildRoot:      %{_tmppath}/%{name}-%{version}-build
 
 %description
 ISL is a library for manipulating sets and relations of integer points
@@ -58,25 +57,23 @@ bounded by linear constraints.
 
 %build
 %configure --disable-static
-make %{?_smp_mflags} V=1
+%make_build
 
 %check
-make %{?_smp_mflags} check
+%make_build check
 
 %install
 %make_install
-rm -f  %{buildroot}%{_libdir}/*.la
+find %{buildroot} -type f -name "*.la" -delete -print
 rm -f  %{buildroot}%{_libdir}/libisl.so.*-gdb.py
 
 %post -n libisl%{islsover} -p /sbin/ldconfig
 %postun -n libisl%{islsover} -p /sbin/ldconfig
 
 %files -n libisl%{islsover}
-%defattr(-,root,root,-)
 %{_libdir}/libisl.so.%{islsover}*
 
 %files devel
-%defattr(-,root,root,-)
 %{_includedir}/isl
 %{_libdir}/libisl.so
 %{_libdir}/pkgconfig/%{name}.pc