diff --git a/isl.changes b/isl.changes
index 367229f..9a56b80 100644
--- a/isl.changes
+++ b/isl.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Fri Jan 10 08:06:27 UTC 2020 - Martin Liška <mliska@suse.cz>
+
+- Add isl_basic_map_underlying_set-fix.patch from upstream.
+
 -------------------------------------------------------------------
 Fri Jan  3 10:57:47 UTC 2020 - Martin Liška <mliska@suse.cz>
 
diff --git a/isl.spec b/isl.spec
index 4a33ad1..922b115 100644
--- a/isl.spec
+++ b/isl.spec
@@ -26,6 +26,7 @@ Group:          Development/Languages/C and C++
 URL:            http://isl.gforge.inria.fr/
 Source:         http://isl.gforge.inria.fr/isl-%{version}.tar.xz
 Source1:        baselibs.conf
+Patch0:         isl_basic_map_underlying_set-fix.patch
 BuildRequires:  gmp-devel
 BuildRequires:  pkgconfig
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build
@@ -55,6 +56,7 @@ bounded by linear constraints.
 
 %prep
 %setup -q
+%patch0 -p1
 
 %build
 %configure --disable-static
diff --git a/isl_basic_map_underlying_set-fix.patch b/isl_basic_map_underlying_set-fix.patch
new file mode 100644
index 0000000..02a9ad8
--- /dev/null
+++ b/isl_basic_map_underlying_set-fix.patch
@@ -0,0 +1,13 @@
+diff --git a/isl_map.c b/isl_map.c
+index 4271ba545b..acb35a224b 100644
+--- a/isl_map.c
++++ b/isl_map.c
+@@ -5511,6 +5511,8 @@ __isl_give isl_basic_set *isl_basic_map_underlying_set(
+ 	    !isl_space_is_named_or_nested(bmap->dim, isl_dim_out))
+ 		return bset_from_bmap(bmap);
+ 	bmap = isl_basic_map_cow(bmap);
++	if (!bmap)
++		return NULL;
+ 	space = isl_basic_map_take_space(bmap);
+ 	space = isl_space_underlying(space, bmap->n_div);
+ 	bmap = isl_basic_map_restore_space(bmap, space);