diff --git a/debian/util.sh b/debian/util.sh
index 052762b91c..4a5214a9bb 100755
--- a/debian/util.sh
+++ b/debian/util.sh
@@ -357,6 +357,16 @@ build_debs () {
   echo ${dsc%.dsc}_${arch}.changes
 }
 
+default_distros () {
+  local host_distro="Debian"
+  test -z "$(which lsb_release)" || host_distro="$(lsb_release -is)"
+  case "$host_distro" in
+    Debian) echo "sid jessie wheezy" ;;
+    Ubuntu) echo "utopic trusty" ;;
+    *) err "Unknown distribution" ;;
+  esac
+}
+
 build_all () {
   local OPTIND OPTARG
   local orig_opts="" dsc_opts="" deb_opts="" modlist=""
@@ -385,25 +395,7 @@ build_all () {
   done
   shift $(($OPTIND-1))
   [ -n "$archs" ] || archs="amd64 i386"
-  if [ -z "$distros" ]; then
-    local default_distros="sid jessie wheezy"
-    if [ -z "$(which lsb_release)" ]; then
-      distros="$default_distros"
-    else
-      case "$(lsb_release -is)" in
-        Debian)
-          distros="$default_distros"
-          ;;
-        Ubuntu)
-          distros="utopic trusty"
-          ;;
-        *)
-          echo "Unknown distribution"
-          exit -1
-          ;;
-      esac
-    fi
-  fi
+  [ -n "$distros" ] || distros="$(default_distros)"
   ! $depinst || aptitude install -y \
     rsync git less cowbuilder ccache \
     devscripts equivs build-essential